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About this blog

I am a Neonatologist trained in Winnipeg, Manitoba and Edmonton, Alberta.  My current position is Section Head of Neonatology in Manitoba and over my career my interests have meandered from time to time.  I have been a past Program Director of Neonatology and Medical Director for a level II Intensive Care Unit prior to relocating to Winnipeg become a Section Head.

Welcome to my blog which I hope will provide a forum for discussion on topics that are of interest to Neonatologists, trainees, all health care professionals and in some cases parents of those we care for.  My intent is to post opinions and analysis on both items from the media and literature that pertain to neonates.  While I have many interests, my particular motivation is to find ways to reduce discomfort for the patients that we care for.  Whether it is through the use of non-invasive testing or finding a way to improve the patient experience this is where I find myself most energized.

I chose the picture for this site as since the inception of this site there is hardly a country that has not had an individual or many people view posts.  Moreover I have received comments from many people from so many different countries that have inspired me to think not just about the impact of these posts in North America but more globally as well.

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Entries in this blog

 

Can video laryngoscopes reduce risk of harm from intubation?

The modern NICU is one that is full of patients on CPAP these days. As I have mentioned before, the opportunity to intubate is therefore becoming more and more rare is non-invasive pressure support becomes the mainstay of therapy. Even for those with established skills in placing an endotracheal tube, the number of times one gets to do this per year is certainly becoming fewer and fewer. Coming to the rescue is the promise of easier intubations by being able to visualize an airway on a screen using a video laryngoscope. The advantage to the user is that anyone who is watching can give you some great tips and armed with this knowledge you may be better able to determine how to adjust your approach. For those of you who have followed the blog for some time, you will recall this is not the first time video laryngoscopy has come up. I have spoken about this before in Can Video Laryngoscopy Improve Trainee Success in Intubation.  In that piece, the case was made that training residents how to intubate using a video laryngoscope (VL) improves their success rate. An additional question that one might ask though has to do with the quality of the intubation.  What if you can place a tube using a video laryngoscope but the patient suffers in some way from having that piece of equipment in the mouth?  Lucky for us some researchers from the Children's Hospital of Philadelphia have completed a study that can help answer this additional question. Video Laryngoscopy may work but does it cause more harm than good? Using a video laryngoscope requires purchasing one first and they aren't necessarily cheap.  If they were to provide a better patient experience though the added cost might well be worth it.  Pouppirt NR et al published Association Between Video Laryngoscopy and Adverse Tracheal Intubation-Associated Events in the Neonatal Care Unit.  This study was a retrospective comparison of two groups; one having an intubation performed with a VL (n=161 or 20% of the group) and the other with a standard laryngoscope (644 or 80% of the group).  The study relied on the use of the National Emergency Airway Registry for Neonates (NEAR4NEOs), which records all intubations from a number of centres using an online database and allows for analysis of many different aspects of intubations in neonates.  In this case the data utilized though was from their centre only to minimize variation in premedication and practitioner experience. Tracheal intubation adverse events (TIAEs) were subdivided into severe (cardiac arrest, esophageal intubation with delayed recognition, emesis with witnessed aspiration, hypotension requiring intervention (fluid and/or vasopressors), laryngospasm, malignant hyperthermia, pneumothorax/pneumomediastinum, or direct airway injury) vs non-severe (mainstem bronchial intubation, esophageal intubation with immediate recognition, emesis without aspiration, hypertension requiring therapy, epistaxis, lip trauma, gum or oral trauma, dysrhythmia, and pain and/or agitation requiring additional medication and causing a delay in intubation. Looking at the patient characteristics and outcomes, some interesting findings emerge. Patients who had the use of the VL were older and weighed more.  They were more likely to have the VL used for airway obstruction than respiratory failure and importantly were also more likely to receive sedation/analgesia and paralysis.  These researchers have also recently shown that the use of paralysis is associated with less TIAEs so one needs to bear this in mind when looking at the rates of TIAEs.  There were a statistically significant difference in TIAEs of any type of 6% in the VL group to 19% in the traditional laryngoscopy arm but severe TIAEs showed not difference. Given that several of the baseline characteristics might play a role in explaining why VL seemed superior in terms of minimizing risk of TIAEs by two thirds, the authors performed a multivariable analysis in which they took all factors that were different into account and then looked to see if there was still an effect of the VL despite these seemingly important differences.  Interestingly, us of VL showed an Odds ratio of 0.43 (0.21,0.87 95% CI) in spite of these differences. What does it mean? Video laryngoscopy appears to make a difference to reducing the risk on TIAEs as an independent factor.  The most common TIAE was esophageal intubation at 10% and reducing that is a good thing as it leads to fewer intubation attempts.  This was also sen as the first attempt success was 63% in the VL group vs 44% in the other. Now we need to acknowledge that this was not a randomized controlled trial so it could indeed be that there are other factors that the authors have not identified that led to improvements in TIAEs as well.  What makes this study so robust though is the rigour with which the centre documents all of their intubations using such a detailed registry.  By using one centre much of the variability in practice between units is eliminated so perhaps these results can be trusted.  Would your centre achieve these same results? Maybe not but it would certainly be interesting to test drive one of these for a period of time see how it performs.

AllThingsNeonatal

AllThingsNeonatal

 

Was adding placement of EKG leads to NRP a good idea after all?

It is hard to believe but it has been almost 3 years since I wrote a piece entitled A 200 year old invention that remains king of all tech in newborn resuscitation. In the post I shared a recent story of a situation in which the EKG leads told a different story that what our ears and fingers would want us to believe. The concept of the piece was that in the setting of pulseless electrical activity (where there is electrical conductance in the myocardium but lack of contraction leaves no blood flow to the body) one could pick up a signal from the EKG leads when there is in fact no pulse or perfusion to vital organs. This single experience led me to postulate that this situation may be more common than we think and the application of EKG leads routinely could lead to errors in decision making during resuscitation of the newborn. It is easy to see how that could occur when you think about the racing pulses of our own in such situations and once chest compressions start one might watch the monitor and forget when they see a heart rate of 70 BPM to check for a corresponding pulse or listen with the stethoscope. I could see for example someone stopping chest compressions and continuing to provide BVM ventilation despite no palpable pulse when they see the QRS complex clearly on the monitor. I didn’t really have much evidence to support this concern but perhaps there is a little more to present now. A Crafty Animal Study Provides The Evidence I haven’t presented many animal studies but this one is fairly simple and serves to illustrate the concern in a research model. For those of you who haven’t done animal research, my apologies in advance as you read what happened to this group of piglets. Although it may sound awful, the study has demonstrated that the concern I and others have has is real. For this study 54 newborn piglets (equivalent to 36-38 weeks GA in humans) were anesthetized and had a flow sensor surgically placed around the carotid artery.  ECG leads were placed as well and then after achieving stabilization, hypoxia was induced with an FiO2 of 0.1 and then asphyxia by disconnecting the ventilator and clamping the ETT.  By having a flow probe around the carotid artery the researchers were able to determine the point of no cardiac output and simultaneously monitor for electrical activity via the EKG leads.  Auscultation for heart sounds was performed as well. The results essentially confirm why I have been concerned with an over reliance on EKG leads.   Of the 57 piglets, 14 had asystole and no carotid flow but in 23 there was still a heart rate present on the EKG with no detectable carotid flow. This yields a sensitivity of only 37%.  Moreover, the overall accuracy of the ECG was only 56%. Meanwhile the stethoscope which I have referred to previously as the “king” in these situations had 100% sensitivity so remains deserving of that title. What do we do with such information? I think the results give us reason to pause and remember that faster isn’t always better.  Previous research has shown that signal acquisition with EKG leads is faster than with oximetry.  While a low heart rate detected quickly is helpful to know what the state of the infant is and begin the NRP pathway, we simply can’t rely on the EKG to tell us the whole story.  We work in interdisciplinary teams and need to support one another in resuscitations and provide the team with the necessary information to perform well.  The next time you are in such a situation remember that the EKG is only one part of the story and that auscultation for heart sounds and palpation of the umbilical cord for pulsation are necessary steps to demonstrate conclusively that you don’t just have a rhythm but a perfusing one. I would like to thank the Edmonton group for continuing to put out such important work in the field of resuscitation!

AllThingsNeonatal

AllThingsNeonatal

 

You don’t plan to fail. You fail to plan

I am fortunate to work with a group of inter-professionals who strive for perfection.  When you connect such people with those with skills in multimedia you create the opportunity for education.  I can’t say enough about the power of education and moreover the ability to improve patient outcomes when it is done well. With this post I am going to be starting to share a collection of videos that I will release from time to time.  The hope with any release like this is that you the reader wherever you are may find some use from these short clips.  My thanks to the team that put these together as the quality is beyond compare and the HD quality is great for viewing on any device. Placing A Chest Tube Can Be A Difficult Thing As I said to a colleague in training the other day, a chest tube may seem daunting but once you see how it is done it loses some of its intimidation.  Having said that, once you see it placed it can be a long time between opportunities for you to view another.  That is where having a repository of videos comes in that you can watch prior to the next opportunity.  These very short clips are easy to access when needed and may calm the nerves the next time you are called to place a chest tube. A Word About Chest Tubes The videos in question demonstrate how to place a Thal quick chest tube. In case this looks foreign to you it may be because you are using the older generation style of chest tubes that come equipped with a trocar.  Even without the use of the trocar, these rigid tubes carry a significant risk of lung laceration or other tissue injury.  For a review of such complications related to chest tube insertion see Thoracostomy tubes: A comprehensive review of complications and related topics. The jury as they say is still out with respect to the use of these softer chest tube sets.  There is no question that they are easier to place than the traditional thoracostomy tube.  Their pliability though does carry a significant risk of kinking or blockage as we have seen in some patients when the Thal chest tube set is used to drain fluid in particular.  Less of an issue with air leaks. Start of a series This post I suppose marks a slightly new direction for the blog.  While I thoroughly enjoy educating you with the posts about topics of interest I see an opportunity to help those who are more visual in their learning.  The videos will be posted over the next while with accompanying written posts such as this.  They can be accessed on my Youtube channel at All Things Neonatal YouTube To receive regular updates as new videos are added feel free to subscribe! Lastly a big thank you to NS, RH and GS without whom none of this would have been possible!

AllThingsNeonatal

AllThingsNeonatal

 

Can’t intubate to give surfactant? Maybe try this!

Intubation is not an easy skill to maintain with the declining opportunities that exist as we move more and more to supporting neonates with CPAP.  In the tertiary centres this is true and even more so in rural centres or non academic sites where the number of deliveries are lower and the number of infants born before 37 weeks gestational age even smaller.  If you are a practitioner working in such a centre you may relate to the following scenario.  A woman comes in unexpectedly at 33 weeks gestational age and is in active labour.  She is assessed and found to be 8 cm and is too far along to transport.  The provider calls for support but there will be an estimated two hours for a team to arrive to retrieve the infant who is about to be born.  The baby is born 30 minutes later and develops significant respiratory distress.  There is a t-piece resuscitator available but despite application the baby needs 40% oxygen and continues to work hard to breathe.  A call is made to the transport team who asks if you can intubate and give surfactant.  Your reply is that you haven’t intubated in quite some time and aren’t sure if you can do it.  It is in this scenario that the following strategy might be helpful. Surfactant Administration Through and Laryngeal Mask Airway (LMA) Use of an LMA has been taught for years in NRP now as a good choice to support ventilation when one can’t intubate.  The device is easy enough to insert and given that it has a central lumen through which gases are exchanged it provides a means by which surfactant could be instilled through a catheter placed down the lumen of the device.  Roberts KD et al published an interesting unmasked but randomized study on this topic Laryngeal Mask Airway for Surfactant Administration in Neonates: A Randomized, Controlled Trial. Due to size limitations (ELBWs are too small to use this in using LMA devices) the eligible infants included those from 28 0/7 to 35 6/7 weeks and ≥1250 g.  The infants needed to all be on CPAP +6 first and then fell into one of two treatment groups based on the following inclusion criteria: age ≤36 hours,
(FiO2) 0.30-0.40 for ≥30 minutes (target SpO2 88% and 92%), and chest radiograph and clinical presentation consistent with RDS.
Exclusion criteria included prior mechanical ventilation or surfactant administration, major congenital anomalies, abnormality of the airway, respiratory distress because of an etiology other than RDS, or an Apgar score <5 at 5 minutes of age. Procedure & Primary Outcome After the LMA was placed a y-connector was attached to the proximal end.  On one side a CO2 detector was placed and then a bag valve mask in order to provide manual breaths and confirm placement over the airway.  The other port was used to advance a catheter and administer curosurf in 2 mL aliquots.  Prior to and then at the conclusion of the procedure the stomach contents were aspirated and the amount of surfactant determined to provide an estimate of how much surfactant was delivered to the lungs.  The primary outcome was treatment failure necessitating intubation and mechanical ventilation in the first 7 days of life.  Treatment failure was defined upfront and required 2 of the following: (1) FiO2 >0.40 for >30
minutes (to maintain SpO2 between 88% and 92%), (2) PCO2 >65 mmHg on arterial or capillary blood gas or >70 on venous blood gas, or (3) pH <7.22 or 1 of the following: (1)  recurrent or severe apnea, (2) hemodynamic instability requiring pressors, (3) repeat surfactant dose, or (4) deemed necessary by medical provider. Did it work? It actually did. Of the 103 patients enrolled (50 LMA and 53 control) 38% required intubation in the LMA group vs 64% in the control arm.  The authors did not reach their desired enrollment based on their power calculation but that is ok given that they found a difference.  What is really interesting is that they found a difference in the clinical end point despite many infants clearly not receiving a full dose of surfactant as measured by gastric aspirate. Roughly 25% of the infants were found to have not received any surfactant, 20% had >50% of the dose in the stomach and the other 50+% had < 10% of the dose in the stomach meaning that the majority was in fact deposited in the lungs.  I suppose it shouldn’t come as a surprise that among the secondary outcomes the duration length of mechanical ventilation did not differ between two groups which I presume occurred due to the babies needing intubation being similar.  If you needed it you needed it so to speak. Further evidence though of the effectiveness of the therapy was that the average FiO2 30 minutes after being treated was significantly lower in the group with the LMA treatment 27 vs 35%.  What would have been interesting to see is if you excluded the patients who received little or no surfactant, how did the ones treated with intratracheal deposition of the dose fare?  One nice thing to see though was the lack of harm as evidenced by no increased rate of pneumothorax, prolonged ventilation or higher oxygen. Should we do this routinely? There was a 26% reduction in intubations in te LMA group which if we take this as the absolute risk reduction means that for every 4 patients treated with an LMA surfactant approach, one patient will avoid intubation.  That is pretty darn good!  If we also take into account that in the real world, if we thought that little of the surfactant entered the lung we would reapply the mask and try the treatment again.  Even if we didn’t do it right away we might do it hours later. In a tertiary care centre, this approach may not be needed as a primary method.  If you fail to intubate though for surfactant this might well be a safe approach to try while waiting for a more definitive airway.  Importantly this won’t help you below 28 weeks or 1250g as the LMA is too small but with smaller LMAs might this be possible.  Stay tuned as I suspect this is not the last we will hear of this strategy!    

AllThingsNeonatal

AllThingsNeonatal

 

It’s time to approach nutrition in extreme preemies as if it were a drug

One of the benefits of operating this site is that I often learn from the people reading these posts as they share their perspectives.  On a recent trip I was reunited with Boubou Halberg a Neonatologist from Sweden whom I hadn’t seen in many years. I missed him on my last trip to Stockholm as I couldn’t make it to Karolinska  University but we managed to meet each other in the end.  As we caught up and he learned that I operated this site he passed along a paper of his that left an impact on me and I thought I would share with you. When we think about treating an infant with a medicinal product, we often think about getting the right drug, right dose and right administration (IV, IM or oral) for maximum benefit to the patient.  When it comes to nutrition we have certainly come a long way and have come to rely on registered dieticians where I work to handle a lot of the planning when it comes to getting the right prescription for our patients.  We seem comfortable though making some assumptions when it comes to nutrition that we would never make with respect to their drug counterparts.  More on that later… A Swedish Journey to Ponder Westin R and colleagues (one of whom is my above acquaintance) published a seven year retrospective nutritional journey in 2017 from Stockholm entitled Improved nutrition for extremely preterm infants: A population based observational study.  After recognizing that over this seven year period they had made some significant changes to the way they approached nutrition, they chose to see what effect this had on growth of their infants from 22 0/7 to 26 6/7 weeks over this time by examining four epochs (2004-5, 2006-7, 2008-9 and 2010-11.  What were these changes?  They are summarized beautifully in the following figure. Not included in the figure was a progressive change as well to a more aggressive position of early nutrition in the first few days of life using higher protein, fat and calories as well as changes to the type of lipid provided being initially soy based and then changing to one primarily derived from olive oil.  Protein targets in the first days to weeks climbed from the low 2s to the mid 3s in gram/kg/d while provision of lipid as an example doubled from the first epoch to the last ending with a median lipid provision in the first three days of just over 2 g/kg/d. While figure 3 from the paper demonstrates that regardless of time period there were declines in growth across all three measurements compared to expected growth patterns, when one compares the first epoch in 2004-2005 with the last 2010-11 there were significant protective effects of the nutritional strategy in place.  The anticipated growth used as a standard was based on the Fenton growth curves. What this tells us of course is that we have improved but still have work to do.  Some of the nutritional sources as well were donor breast milk and based on comments coming back from this years Pediatric Academic Society meeting we may need to improve how that is prepared as growth failure is being noted in babies who are receiving donated rather than fresh mother’s own milk.  I suspect there will be more on that as time goes by. Knowing where you started is likely critical! One advantage they have in Sweden is that they know what is actually in the breast milk they provide.  Since 1998 the babies represented in this paper have had their nutritional support directed by analyzing what is in the milk provided by an analyzer.  Knowing the caloric density and content of protein, carbohydrates and fats goes a long way to providing a nutritional prescription for individual infants.  This is very much personalized medicine and it would appear the Swedes are ahead of the curve when it comes to this.  in our units we have long assumed a caloric density of about 68 cal/100mL.  What if a mother is producing milk akin to “skim milk” while another is producing a “milkshake”.  This likely explains why some babies despite us being told they should be getting enough calories just seem to fail to thrive.  I can only speculate what the growth curves shown above would look like if we did the same study in units that actually take a best guess as to the nutritional content of the milk they provide. This paper gives me hope that when it comes to nutrition we are indeed moving in the right direction as most units become more aggressive with time.  What we need to do though is think about nutrition no different than writing prescriptions for the drugs we use and use as much information as we can to get the dosing right for the individual patient!

AllThingsNeonatal

AllThingsNeonatal

 

The days of the Apgar score may be numbered

One of the first things a student of any discipline caring for newborns is how to calculate the apgar score at birth.  Over 60 years ago Virginia Apgar created this score as a means of giving care providers a consistent snapshot of what an infant was like in the first minute then fifth and if needed 10, 15 and so on if resuscitation was ongoing.  For sure it has served a useful purpose as an apgar score of 0 and 0 gives one cause for real worry.  What about a baby with an apgar of 3 and 7 or 4 and 8?  There are certainly infants who have done very well who initially had low apgar scores and conversely those who had higher apgar scores who have had very significant deleterious outcomes including death.  I don’t mean to suggest that the apgar scores don’t provide any useful predictive value as they are used as part of the criteria to determine if a baby merits whole body cooling or not.  The question is though after 60+ years, has another score been created to provide similar information but enhance the predictive value derived from a score? The Neonatal Resuscitation and Adaptation Score (NRAS) Back in 2015 Jurdi et al published  Evaluation of a Comprehensive Delivery Room Neonatal Resuscitation and Adaptation Score (NRAS) Compared to the Apgar Score.  This new score added into a ten point score resuscitative actions taken at the 1 and 5 minute time points to create a more functional score that included interventions.  The other thing this new score addressed was more recent data that indicated a blue baby at birth is normal (which is why we have eliminated asking the question “is the baby pink?” in NRP.  Knowing that, the colour of the baby in the apgar score may not really be that relevant.  Take for example a baby with an apgar score of 3 at one minute who could have a HR over 100 and be limp, blue and with shallow breathing.  Such a baby might get a few positive pressure breaths and then within 10 seconds be breathing quite well and crying.  Conversely, they might be getting ongoing PPV for several minutes and need oxygen.  Were they also getting chest compressions?  If I only told you the apgar score you wouldn’t have much to go on.  Now look at the NRAS and compare the information gathered using two cardiovascular (C1&2), one neurological test (N1) and two respiratory assessments (R1&2).   The authors in this study performed a pilot study on only on 17 patients really as a proof of concept that the score could be taught and implemented.  Providers reported both scores and found “superior interrater reliability (P < .001) and respiratory component reliability (P < .001) for all gestational ages compared to the Apgar score.”   A Bigger Study Was Needed The same group in 2018 this time led by Witcher published Neonatal Resuscitation and Adaptation Score vs Apgar: newborn assessment and predictive ability.  The primary outcome was the ability of a low score to predict mortality with a study design that was a non-inferiority trial.  All attended deliveries were meant to have both scores done but due to limited numbers of trained personnel who could appropriately administer both scores just under 90% of the total deliveries were assigned scores for comparison.  The authors sought to recruit 450 infants to show that a low NRAS score (0–3) would not be inferior to a similar Apgar at predicting death.  Interestingly an interim analysis found the NRAS to be superior to Apgar when 75.5% of the 450 were enrolled, so the study was stopped.  What led the apgar score to perform poorly in predicting mortality (there were only 12 deaths though in the cohort) was the fact that 49 patients with a 1 minute apgar score of 0-3 survived compared to only 7 infants with a low NRAS score. The other interesting finding was the ability of the NRAS to predict the need for respiratory support at 48 hours with a one minute apgar score of 0-3 being found in 39% of those on support compared to 100% of those with a low NRAS.  Also at 5 minutes a score of 4-6 for the apgar was found in 48% of those with respiratory support at 48 hours vs 87% of those with a similar range NRAS.  These findings were statistically significant while a host of other conditions such as sepsis, hypoglycemia, hypothermia and others were no different in terms of predictive ability of the scores. An Even Bigger Study is Needed To be sure, this study is still small and missed just over 90% of all deliveries so it is possible there is some bias that is not being detected here.  I do think there is something here though which a bigger study that has an army of people equipped to provide the scoring will add to this ongoing story.  Every practitioner who resuscitates an infant is asked at some point in those first minutes to hour “will my baby be ok?”.  The truth is that the apgar score has never lived up to the hope that it would help us provide an accurate clairvoyant picture of what lies ahead for an infant.   Where this score gives me hope is that a score which would at the very least help me predict whether an infant would likely still be needing respiratory support in 48 hours provides the basic answer to the most common question we get in the unit once admitted; “when can I take my baby home”.  Using this score I could respond with some greater confidence in saying “I think your infant will be on support for at least 48 hours”.  The bigger question though which thankfully we don’t have to address too often for the sickest babies at birth is “will my baby survive?”.  If a larger study demonstrates this score to provide a greater degree of accuracy then the “Tipping Point” might just be that to switching over to the NRAS and leaving the apgar score behind.  That will never happen overnight but medicine is always evolving and with time you the reader may find yourself becoming very familiar with this score!

AllThingsNeonatal

AllThingsNeonatal

 

Don’t let the cord gas fool you

It has to be one of the most common questions you will hear uttered in the NICU.  What were the cord gases?  You have a sick infant in front of you and because we are human and like everything to fit into a nicely packaged box we feel a sense of relief when we are told the cord gases are indeed poor.  The congruence fits with our expectation and that makes us feel as if we understand how this baby in front of us looks the way they do. Take the following case though and think about how you feel after reading it.  A term infant is born after fetal distress (late deceleration to as low as 50 BPM) is noted on the fetal monitor.  The infant is born flat with no heart rate and after five minutes one is detected.  By this point the infant has received chest compressions and epinephrine twice via the endotracheal tube.  The cord gases are run as the baby is heading off to the NICU for admission and low and behold you get the following results back; pH 7.21, pCO2 61, HCO3 23, lactate 3.5.   You find yourself looking at the infant and scratching your head wondering how the baby in front of you that has left you moist with perspiration looks as bad as they do when the tried and true cord gas seems to be betraying you.  To make matters worse at one hour of age you get the following result back; pH 6.99, pCO2 55, HCO3 5, lactate 15.  Which do you believe?  Is there something wrong with the blood gas analyzer? How Common Is This Situation You seem to have an asphyxiated infant but the cord gas isn’t following what you expect as shouldn’t it be low due to the fetal distress that was clearly present?  It turns out, a normal or mildly abnormal cord gas may be found in asphyxiated infants just as commonly as what you might expect.  In 2012 Yeh P et al looked at this issue in their paper The relationship between umbilical cord arterial pH and serious adverse neonatal outcome: analysis of 51,519 consecutive validated samples. The authors sampled a very large number of babies over a near 20 year period to come up with a sample of 51519 babies and sought to pair the results with what they knew of the outcome for each baby. This is where things get interesting.  When looking at the outcome of encephalopathy with seizures and/or death you will note that only 21.71% of the babies with this outcome had a gas under 7.00.  If you include those under 7.10 as still being significantly distressed then this percentage rises to 34.21%.  In other words almost 66% of babies who have HIE with seizures and/or death have a arterial cord pH above 7.1!  The authors did not look at encephalopathy without seizures but these are the worst infants and almost 2/3 have a cord gas that you wouldn’t much as glance at and say “looks fine” How do we reconcile this? The answer lies in the fetal circulation.  When an fetus is severely stressed, anaerobic metabolism takes over and produces lactic acid and the metabolic acidosis that we come to expect.  For the metabolites to get to the umbilcal artery they must leave the fetal tissues and enter the circulation.  If the flow of blood through these tissues is quite poor in the setting of compromised myocardial contractility the acids sit in the tissues.  The blood that is therefore sitting in the cord at the time of sampling actually represents blood that was sent to the placenta “when times were good”.  When the baby is delivered and we do our job of resuscitating the circulation that is restored then drives the lactic acid into the blood stream and consumes the buffering HCO3 leading to the more typical gases we are accustomed to seeing and reestablishing the congruence our brains so desire.  This in fact forms the basis for most HIE protocols which includes a requirement of a cord gas OR arterial blood gas in the first hour of life with a pH < 7.00. Acidosis May Be Good For the Fetus To bend your mind just a little further, animal evidence suggests that those fetuses who develop acidosis may benefit from the same and be at an advantage over those infants who don’t get acidemia.  Laptook AR et al published Effects of lactic acid infusions and pH on cerebral blood flow and metabolism.  In this study of piglets, infusion of lactic acid improved cerebral blood flow.  I would suggest improvement in cerebral blood flow of the stressed fetus would be a good thing.  Additionally we know that lactate may be used by the fetus as additional metabolic fuel for the brain which under stress would be another benefit.  Finally the acidemic fetus is able to offload O2 to the tissues via the Bohr effect.  In case you have forgotten this phenomenon, it is the tendency for oxygen to more readily sever its tie to hemoglobin and move into the tissues. I hope you have found this as interesting as I have in writing it.  The next time you see a good cord gas in a depressed infant, pause for a few seconds and ask yourself is this really a good or a bad thing?

AllThingsNeonatal

AllThingsNeonatal

 

At 22 weeks of gestation does your faith matter most to outcome?

Recent statements by the American Academy of Pediatric’s, NICHD, the American College of Obstetricians and Gynecologists (ACOG), the Society for Maternal-Fetal Medicine (SMFM), and recommend selective approaches to mothers presenting between 22 0/7 to 22 6/7 weeks. The decision to provide antenatal steroids is only recommended if delivery is expected after 23 weeks. Furthermore the decision to resuscitate is based on an examination of a number of factors including a shared decision with the family. In practice this leads to those centres believing this is mostly futile generally not resuscitating or offering steroids while other more optimistic hospitals having higher rates of proactive (steroids and resuscitation) rates. Then there are other centres where the standard approach is proactive such as one in Uppsala, Sweden where this approach is used almost exclusively. What would happen then if one compared the outcome for infants born at 22 weeks between this hospital and another where a selective approach is generally offered. In this case you would have a lot of experience with resuscitating infants at 22 weeks and the other a fraction of all presenting as a few to many would receive compassionate care. This is exactly what has now happened. A Tale of Two Cities The University Children’s Hospital, Uppsala, Sweden has been compared retrospectively to Nationwide Children’s Hospital, Columbus, Ohio, USA (NCH) with respect to survival and outcomes for their infants born at 22 weeks. The paper by Backes CH et al entitled Outcomes following a comprehensive versus a selective approach for infants born at 22 weeks of gestation tells a very interesting story about the power of belief or faith that one can accomplish something if they set their mind to it. The authors examined a period from 2006-2015, dividing this time into two epochs with the first being 2006-2010 to account for differing practices and resources over time. Given that Uppsala took a proactive approach to all of their 40 live born infants during this time, it provided an opportunity to look at the 72 infants who were live born in the Ohio and examine their differences. In Ohio the approach was as follows; 16 (22%) received proactive care, 18 (25%) received inconsistent care (steroids but no resuscitation), and 38 (53%) received comfort care. In other words, although the total number of infants live born in Ohio was almost double that of Uppsala, only 16 were proactively treated in Ohio compared to all 40 in Uppsala. The differences in outcome are striking Survival in delivery room: (38/40, 95% vs 12/16, 75%; P = 0.049) Provision of delivery room surfactant: (40/40, 100% vs 9/16, 56%; P<0.01) Survival at 24 h (37/40, 93% vs. 9/16, 56%; P < 0.01). Survival to 1 year (21/40, 53% vs. 3/16, 19%; P < 0.05). Among the infants treated proactively, median age of death (17 postnatal days at range 0 h–226 days vs. 3 postnatal hours at NCH, range 0 h–10 days; P < 0.01). All surviving infants had BPD All infants surviving to initial hospital discharge were alive at 18 months’ postnatal age. With respect to long term outcome the authors note: “Outpatient follow-up (qualitative or non-qualitative neurodevelopmental testing) was available in 26 out of 27 infants (96%) Eleven of the 26 (42%) were unimpaired, and all unimpaired infants were in the UUCH cohort. Among the 15 infants with impairment at UUCH, 3 had mild impairment and 12 had moderate or severe impairment. All surviving infants at NCH had moderate or severe impairment.” A word about antenatal steroids as well. In Uppsala 85% of mothers received 2 doses of antenatal steroids vs 25% in Ohio. People sometimes question whether ANS at this age are effective. It is interesting to note that 44% of babies in the Ohio group vs 3% p<0.01 received chest compressions +/- epinephrine in the delivery room. Might this explain the better state of some of these infants at birth? The Power of Belief When I do rounds I often remark that try as we might we can’t will babies to do better. I also commonly say however that we need to be optimistic and although I am accused of seeing the world through rose coloured glasses I think there is an important lesson to be learned from this study. This comparison is really a contrast between a system that believes they can do a good thing for these families by actively promoting a proactive approach vs a system in which I imagine a reluctant approach exists even for those infants where a proactive plan is enacted. One sign of this might be that in Sweden 100% of these deliveries had a Neonatologist present vs 75% in the US. It could be due to other factors such as ability of the Neo to get in within time of the delivery however rather than a sign they didn’t feel they were needed due to futility. There is evidence as well that the aggressiveness of the proactive approach also differs between the two sites based on a couple observations. The first is the rate of surfactant provision in the delivery room which was 100% in Sweden but only 56% in the US. The other thing of note is the time of death for those who did not survive. The median time of death in the US was 3 hours vs 17 days in Uppsala. What does this tell us about the approaches? I would imagine (although the numbers are small) that the teams in the US were much more likely to lose hope (or faith) and withdraw early while the other centre possibility motivated by their past successes pushed forward. Remarkably, although one might think that the teams in Uppsala were simply creating significantly impaired survivors, 42% of the survivors were unimpaired from a developmental standpoint in follow-up. All surviving infants though from Ohio had moderate to severe impairment. What this story may also really be about is practice. The reality is that the team in Sweden had over twice the exposure to such infants over time. Although the number presenting at this GA was higher, the ones that actually were resuscitated and given steroids was less than half. One cannot take away though that Uppsala in the end demonstrated that a proactive approach is definitely not futile. Not only can these children survive but almost half will be developmentally intact. We must acknowledge as well though that since this is a retrospective study there may be factors that may have affected the results. As the saying goes “Individual results may vary”. Are the teams the same in both centres in terms of number of Neonatologists? Are there more residents caring for these infants vs fellows? Are the resources the same? What about proximity of the Neonatologist to the hospital? There are other factors such as cohesiveness of the team and communication between team members that may be influencing the results. In the end though, this is a story of a team that believed it could and did. Perhaps seeing the world through rose coloured glasses is not such a bad thing in the end.

AllThingsNeonatal

AllThingsNeonatal

 

Has the Magic Bullet to Prevent Kernicterus Been (Re)Discovered?

As the saying goes "What is old is new again" and that may be applicable here when talking about prevention of kernicterus.  In the 1990s there was a great interest in a class of drugs called mesoporphyrins in the management of hyperbilirubinemia.  The focus of treatment for many years had been elimination of bilirubin through the use of phototherapy but this shifted with the recognition that one could work on the other side of the equation.  That is to prevent the production of bilirubin in the first place. Tin mesoporphyrins (SnMP) have the characteristic of being able to inhibit the enzyme hemo oxygenase quite effectively.  By achieving such blockade the breakdown of heme to carbon monoxide and biliverdin (the precursor of bilirubin) is inhibited.  In so doing, the production of bilirubin is reduced making one less dependent on phototherapy to rid the body of elevated levels.  So simple and as you might imagine a good reason for there to have been significant interest in the product.  One article by Martinez et al entitled Control of severe hyperbilirubinemia in full-term newborns with the inhibitor of bilirubin production Sn-mesoporphyrin. was published in 1999 and demonstrated that infants with severe hyperbilirubinemia between 48-96 hours could have their need for phototherapy eliminated by use of the product compared to 27% of the infants in the control group needing treatment.  Additionally, total bilirubin samples were reduced from a median of 5 to 3 with the use of one IM injection of SnMP.  This small study was hampered though by inability to really look at adverse outcomes despite its effectiveness.  What has been seen however is that SnMP if given to infants who are then treated with white lights can create a rash which is not seen however when special blue light is employed. Two other studies followed exploring the use of SnMP in cases of severe hyperbilirubinemia in term infants and were the subject of a Cochrane review in 2003.  The conclusions of the review essentially became the death nell for the therapy as they were as follows. "...may reduce neonatal bilirubin levels and decrease the need for phototherapy and hospitalization. There is no evidence to support or refute the possibility that treatment with a metalloporphyrin decreases the risk of neonatal kernicterus or of long-term neurodevelopmental impairment due to bilirubin encephalopathy... Routine treatment of neonatal unconjugated hyperbilirubinemia with a metalloporphyrin cannot be recommended at present." The literature after this basically dries up, that is until this month when a paper emerges that is best described as a story of mystery and intrigue! Prophylactic Use of SnMP From 2003 Published in 2016! This paper as you read it almost seems like a conspiracy story.  The paper is by Bhutani et al (as in the nomogram) Clinical trial of tin mesoporphyrin to prevent neonatal hyperbilirubinemia.  The study set out to answer a different question than had been previously studied.  The question here was, if you provided a single IM dose of SnMP to infants who were at or above the 75%ile on the risk nomogram, could you prevent the need for phototherapy or exchange transfusion as the primary outcome.  Secondarily, the authors truly wanted to demonstrate safety of the product and planned on recruiting 800 patients per arm in the study.  The study appeared to be well planned and as with many studies had a safety monitoring committee which was to do interim analyses.  After the first analysis the FDA became involved and recommended studies to look at a prophylactic versus therapeutic approach.  Due to the interim analysis the study had been halted and after the FDA made their suggestion the study was simply never restarted as future studies were planned to look at the effectiveness and safety of the two approaches.  The authors state that they planned on reporting their results in 2006/7 but elected to wait until long term data emerged.  Now finally 9 years later they decided to release the results of the partially completed study.  The story around this study I find as interesting as the results they obtained! So What Happened? Before closing the study they managed to recruit 87 into the intervention arm and 89 into the placebo group and lost none to follow-up.  One dose of SnMP had a significant effect on the trajectory of curves for bilirubin production as can be seen in the first figure.   The graph below demonstrates what percentage of patients had a bilirubin level above 220 umol/L (12.9 mg/dl) after the single injection of SnMP (black bars) compared to placebo (white bars). What can we do with these results? It would be tough to argue anything other than this being an effective treatment to prevent significant hyperbilirubinemia.  Unfortunately, like many studies that were never completed this one remains underpowered to conclusively demonstrate that the use of SnMP is safe in both the short and long term periods.  The absence of such data make it very difficult to recommend SnMP as standard of care.  One has to add to this that while we have evidence to show it reduces the rate of rise of bilirubin, what we don't know is whether in a larger study the incidence of bilirubins > 425 umol/L or the need for exchange transfusion might be reduced.  If this were the case, it would make for a compelling argument to try SnMP. That is the approach for standard of care though.  In the setting of a patient with a known blood group incompatibility who was at high risk for exchange transfusion, if they received IVIG and the bilirubin continued to climb might there be a role here?  I would tend to say yes if we could get our hands on some.  The authors by sharing this data have shown the medication is effective in doing what it is supposed to do.  Given that at least in our centre all of our lights are of the new variety, the risk of rash would be nonexistent.  The risk for kernicterus or at least an exchange transfusion though would not be minimal so if we have this in our toolbox I would after weighing the risks opt to give it. I certainly wonder if there are places out there who have used it and if so what is your experience?

AllThingsNeonatal

AllThingsNeonatal

 

Just Text Me! Enhancing Communication With Families

When you mention electronic medical records to some physicians you get mixed responses.  Some love them and some…well not so much.  These tech heavy platforms promise to streamline workflows and reduce error with drop down menus, some degree of artificial intelligence in providing warnings when you stray too far from acceptable practice but for some who are not so tech savvy they are more of a pain.  I have to admit I am in the camp of believing they are a good thing for patient care as I work in one centre with expanded EMR services and one without and I do find a number of benefits to working with a more robust EMR platform but I respect that not all do. The cell phone on the other hand is everywhere and even the most tech fearful often carry one including most of the parents we care for.  What caught my eye this month was the article by Globus O The use of short message services (SMS) to provide medical updating to parents in the NICU in which an EMR system is described that sends parents a text message at a pre-specified time regarding their infants condition.  I had a visceral reaction at first thought thinking “would I want my cell phone number sent to families?”, “how much time out of the day would all of this take?” and to be a little old fashioned “can’t we just talk on the phone?”.  I am sure there are many other questions that others would have as well.  Having said that as I read through the paper I warmed to the concept and by the end questioned whether we could do the same! The Intervention It turns out the SMS message comes from the EMR and not the personal cell phone of the bedside nurse and is sent out at 9 AM each day.  Each nurse requires only 30 seconds of their day to populate a few questions during the night shift and then the information goes out to the parents. “The text message includes one-sentence prefaces and conclusions and provides updated information that includes the location of the infant’s crib (room and position), the infant’s current weight and whether medical procedures, such as head ultrasound, cardiac echocardiogram or eye examination, were performed. Information regarding acute events or deterioration of the infant’s medical condition are not included in the SMS, but are delivered personally to the parents in real time.” This last sentence is important.  The SMS service will not notify the family that their infant is receiving chest compressions but is there to give them “updates”.  The sceptics out there will likely comment that this should be the job of both nursing and medicine to regularly update the families but thinking about it, how many parents are not there everyday and when they are out of sight how many physicians regularly call them to provide them updates?  No doubt there are some but I would think they are not in the majority. But is it effective? The measurement in this case was through surveys of nursing and families both pre-implementation and afterwards.  Provided in the table below are the scores (means +/- SD) in the pre and post implementation phases of the program. Statement Pre-SMSi N=91 Post SMSi N=87 P-value The physician was available when needed 4.1+/-0.9 4.4+/-0.7 0.002 The physician was patient in answering my questions 4.6+/-0.7 4.9 +/-0.4 0.002 I felt comfortable approaching the physicians 4.3+/-1.0 4.7+/-0.6 0.001 I felt comfortable approaching the nurses 4.4+/-0.8 4.6+/-0.6 0.02 I regularly received information from the physicians regarding my infant’s medical status 3.7+/-1.3 4.1+/-1.1 0.03 These are some pretty powerful outcomes.  The use of what many consider an impersonal form of communication (how many times have I looked at people texting furiously and thought JUST PICK UP THE PHONE!) actually appears to have improved the approachability of the staff in the unit and facilitated information transfer more easily. One other important finding was that when surveyed pre-intervention staff were somewhat sceptical that this would help and moreover were concerned that it would interfere too much with work flow in the day.  Evaluations afterwards did not support these fears and many felt it was an improvement.  In the end the total time spent on this by nursing was estimated to be no more than 30 seconds of each day!  From the parent’s standpoint they certainly saw this as an improvement. The Future At least in our centre we are moving slowly but steadily towards a fully functioning EMR.  Will we have this capability in the software that we use?  After reading this I hope so.  I can see how receiving a daily morning message would prime the family to interact with staff on rounds.  The added benefit is that by knowing that the information would be ready at 9 AM, families could be present with questions already formulated in their minds.  How often do we encourage families to be on rounds and have them listen to a tremendous amount of information and then turn to them with the standard “any questions?”.  While I am sure many of us try and explain matters in lay terms, giving parents a change to mull over the issues first could well enhance the interaction they have with our team in a meaningful way. Time to look into whether this is possible…

AllThingsNeonatal

AllThingsNeonatal

 

NEC & Anemia: Is the truth out there?

A debate broke out recently at one of our rounds when someone asked whether a recent case of NEC was possibly related to a transfusion that a baby received.  Much has been written about Transfusion Associated Necrotizing Enterocolitis (TANEC) with the pendulum swinging back and forth between it existing as a real entity or simply being an association that is not causative in the least.  Using one of my favourite sources, a retrospective analysis of the Canadian Neonatal Network database found no difference in mortality or morbidities for those who had a transfusion and NEC vs those without. Despite this we continue to see those who “hold feeds” for a few hours prior to transfusion and then resume them a few hours later.  Why does this happen? Risk vs Benefit Those who hold feeds argue that in Neonatology we hold feeds for far less.  Furthermore, what is the harm?  If a baby develops NEC within 24 hours of a transfusion and we held the feeds we feel we have done all we could.  If a baby is fed and develops NEC we are left asking “what if?”.  The purists out there would argue the contrary though, that the evidence is not strong enough to support the practice and may require the insertion of an IV which is a painful procedure and places the infant at risk of infection from one or more skin breaks.  Additionally, does the interruption of feeds potentially alter the microbiome of the patient and with it risk potential downstream consequences. In case you are wondering, I have tended to sit on the side of holding a feed although more often when I am asked about it than ordering it upfront.  The fact is I just don’t know.  The evidence has never been solid in this regard but it is hard to ignore the possibility when you have been bitten once or twice before (whether it was causative or not!).  I doubt it really exists but then again what if there is something there? It May Not Be The Transfusion But Anemia Itself A recent paper Association of Red Blood Cell Transfusion, Anemia, and Necrotizing Enterocolitis in Very Low-Birth-Weight Infants may have found a possible explanation to the ongoing debate.  Research papers associating transfusions with NEC may all have one thing in common in that they have not been able to prove causation.  When you have many papers finding the same thing it leads medical teams to begin to believe there is causation.  Something else may be at play at this paper suggests another association which again may not be causative but at least in my mind is perhaps biologically plausible.  It may be that those patients who are transfused when their hemoglobin is below a threshold of 80 g/L are at increased risk of developing NEC rather than all patients transfused. This study was a secondary analysis of a prospective study on transfusion transmission of cytomegalovirus in preterm infants < 1500g.  The authors chose 80 g/L as a cutoff based on previous studies suggesting this threshold as an important one for transfusion practices. Forty eight out of 60 eligible infants developed NEC and it is from this 48 that multivariable analysis sought to identify factors predisposing to the outcome in question of NEC.  The factor with the greatest hazard risk for NEC was severe anemia in a given week with an approximate 6 fold risk (range 2 – 18) while receiving an RBC transfusion in a given week of life did not meet statistical significance. What does this mean? Before embracing the result and concluding we have the answer we have to acknowledge the authors have gone on a fishing expedition of sorts.  Any secondary analysis of a study that is done carries with it some words of warning.  There may be variables that were not controlled for that are affecting the results.  As well when looking at many many variables it could be by chance that something or several things come up by chance.  Lastly it may be that again there is nothing more than an association here at play.  Having said that, there is some biologic plausibility at least here. Delivery of oxygen to the tissues is dependent on HgB level. The oxygen content of blood is described by: O2 content = (gm Hbg)(1.34 ml O2/gm Hbg)(% sat) + 0.003(pO2) = ml O2/dL. Oxygen delivery = cardiac output X O2 concentration (or content) Could RBCs become less deformable and increase viscosity in low O2 environments? This could be the case when the HgB declines below 80 g/L.  Such changes to deformability have been demonstrated at mild levels of hypoxia as might exist in low pO2 conditions at the tissue level with anemia. So imagine we have fewer RBCs carrying as much oxygen as they can but eventually you cross a threshold where there is not enough O2 being delivered at the tissue level and the RBCs become lodged or perhaps sluggish as they move through capillaries of the intestines. Add to this that NEC occurs in watershed areas most commonly and you have the potential setup for NEC. Can we use the results of this study? I suppose statistical purists out there will argue that it is merely an association.  The fact remains that there are many people who are holding feeds for varying amounts of time despite the lack of conclusive evidence that TANEC exists.  I wonder if a middle ground might be to be more cautious and restrict such practice to those with low HgB values below 80 g/L as the authors here have found.  To me at least there is biologic plausibility as outlined above.  It would seem to me that to hold feeds for all babies is excessive and likely without evidence but could the threshold actually matter which it comes to oxygen content.  Given that NEC is a condition related to ischemia, the authors here have provided another association that makes me at the very least scratch my head.

AllThingsNeonatal

AllThingsNeonatal

 

An Old Drug Finds A New Home In The Treatment of BPD.

What is old is new again as the saying goes.  I continue to hope that at some point in my lifetime a “cure” will be found for BPD and is likely to centre around preventing the disease from occurring.  Will it be the artificial placenta that will allow this feat to be accomplished or something else?  Until that day we unfortunately are stuck with having to treat the condition once it is developing and hope that we can minimize the damage.  When one thinks of treating BPD we typically think of postnatal steroids.  Although the risk of adverse neurodevelopmental outcome is reduced with more modern approaches to use, such as with the DART protocol,most practitioners would prefer to avoid using them at all if possible.  We know from previous research that a significant contributor to the development of BPD is inflammation.  As science advanced, the specific culprits for this inflammatory cascade were identified and leukotrienes in particular were identified in tracheal lavage fluid from infants with severe lung disease.  The question then arises as to whether or not one could ameliorate the risk of severe lung disease by halting at least a component of the inflammatory cascade leading to lung damage. Leukotriene Antagonists In our unit, we have tried using the drug monteleukast, an inhibitor of leukotrienes in several patients.  With a small sample it is difficult to determine exactly whether this has had the desired effect but in general has been utilized when “all hope is lost”.  The patient has severe disease already and is stuck on high frequency ventilation and may have already had a trial of postnatal steroids.  It really is surprising that with the identification of leukotriene involvement over twenty years ago it took a team in 2014 to publish the only clinical paper on this topic.  A German team published Leukotriene receptor blockade as a life-saving treatment in severe bronchopulmonary dysplasia.in 2014 and to date as far as I can see remains the only paper using this strategy. Given that we are all looking for ways to reduce BPD and this is the only such paper out there I thought you might want to see what they found.  Would this be worth trying in your own unit?  Well, read on and see what you think! Who was included? This study had an unusual design that will no doubt make statistical purists cringe but here is what they did.  The target population for the intervention were patients with “life threatening BPD”.  That is, in the opinion of the attending Neonatologist the patient had a greater than 50% likelihood of dying and also had to meet the following criteria; born at < 32 weeks GA, <1500g and had to be ventilated at 28 days.  The authors sought a blinded RCT design but the Research Ethics Board refused due to the risk of the drug being low and the patients having such a high likelihood of death.  The argument in essence was if the patients were likely to die and this drug might benefit them it was unethical to deny them the drug.  The authors attempted to enroll all eligible patients but wound up with 11 treated and 11 controls.  The controls were patients either with a contraindication to the drug or were parents who consented to be included in the study as controls but didn’t want the drug.  Therapy was started for all between 28 – 45 days of age and continued for a wide range of durations (111+/-53 days in the study group).  Lastly, the authors derived a score of illness severity that was used empirically: PSC = FiO2 X support + medications – support was equal to 2.5 for a ventilator. 1.5 for CPAP and 1 for nasal cannulae or an oxygen hood – medications were equal to 0.2 for steroids, 0.1 for diruetics or inhaled steroids, 0.05 for methylxanthines or intermittent diruetics. Did it make a difference? The study was very small and each patient who received the medication was matched with one that did not receive treatment.  Matching was based on GA, BW and the PSC with matching done less than 48 hours after enrollment in an attempt to match the severity of illness most importantly.   First off survival in the groups were notably different.  A marked improvement in outcome was noted in the two groups.  Of the deaths in the control group, the causes were all pulmonary and cardiac failure, although three patients died with a diagnosis of systemic inflammatory response syndrome.  That is quite interesting given that monteleukast is an anti-inflammatory medication and none of the patients in the treatment arm experienced this diagnosis. The second point of interest is the trend in the illness severity score over time.  The time points in the figure are time 1 (start of study), time 2 (4 weeks of treatment), time 3 (end of treatment).  These patients improved much more over time than the ones who did not receive treatment. The Grain of Salt As exciting as the results are, we need to acknowledge a couple things.  The study is small and with that the risk of the results appearing to be real but in actual fact there being no effect is not minimal.  As the authors knew who was receiving monteleukast it is possible that they treated the kids differently in the unit.  If you believed that the medication would work or moreover wanted it to work, did you pay more attention on rounds and during a 24 hour period to those infants?  Did the babies get more blood gases and tighter control of ventilation with less damage to the lungs over time?  There are many reasons why these patients could have been different including earlier attempts to extubate.  The fact is though the PSC scores do show that the babies indeed improved more over time so I wouldn’t write it off entirely that they did in fact benefit.  The diagnosis of SIRS is a tough one to make in a newborn and I worry a little that knowing the babies didn’t receive an anti-inflammatory drug they were “given” that diagnosis. Would I use it in spite of these faults? Yes.  We have used it in such cases but I can’t say for sure that it has worked.  If it does, the effect is not immediate and we are left once we start it not knowing how long to treat.  As the authors here say though, the therapeutic risk is low with a possibly large benefit.  I doubt it is harmful so the question we are left asking is whether it is right for you to try in your unit?  As always perhaps a larger study will be done to look at this again with a blinded RCT structure as the believers won’t show up I suspect without one!    

AllThingsNeonatal

AllThingsNeonatal

 

Intubating to give surfactant is so 2017!

A catchy title for sure and also an exaggeration as I don’t see us abandoning the endotracheal tube just yet.  There has been a lot of talk about less invasive means of giving surfactant and the last few years have seen several papers relating to giving surfactant via a catheter placed in the trachea (MIST or LISA techniques as examples).  There may be a new kid on the block so to speak and that is aerosolized surfactant.  This has been talked about for some time as well but the challenge had been figuring out how to aerosolize the fluid in such a way that a significant amount of the surfactant would actually enter the trachea.  This was really a dream of many Neonatologists and based on a recently published paper the time may be now for this technique to take off. A Randomized Trial of Aerosolized Surfacant Minocchieri et al as part of the CureNeb study team published Nebulised surfactant to reduce severity of respiratory distress: a blinded, parallel, randomised controlled trial. This trial set out to obtain a sample size of 70 patients between 29 0/7 to 33 6/7 weeks to demonstrate a difference in need for intubation from 30% down to 5% in patients treated with CPAP (30% was based on the historical average).  The authors recognizing that the babies in this GA bracket might behave differently, further stratified the randomization into two groups being 29 0/7 – 31 6/7 weeks and 32 0/7 to 33 6/7 weeks.  Those babies who were on CPAP and met the following criteria for intubation were either intubated in the control group and given surfactant (curosurf) using the same protocol as those nebulized or had surfactant delivered via nebulisation (200 mg/kg: poractant alfa) using a customised vibrating membrane nebuliser (eFlow neonatal). Surfactant nebulisation(100 mg/kg) was repeated after 12 hours if oxygen was still required.  The primary dichotomous outcome was the need for intubation within 72 hours of life, and the primary continuous outcome was the mean duration of mechanical ventilation at 72 hours of age. Criteria for intubation 1. FiO2 >0.35 over more than 30 min OR FiO2 >0.45 at
anytime.
2. More than four apnea/hour OR two apnea requiring BVM
3. Two cap gases with pH <7.2 and PaCO2 >65 mm Hg (or) >60 mm Hg if arterial blood gas sample).
4. Intubation deemed necessary by the attending physician. Did It Work? Eureka! It seemed to work as 11 of 32 infants were intubated in the surfactant nebulisation group within 72 hours of birth vs.22 out of 32 infants receiving CPAP alone (RR (95% CI)=0.526 (0.292 to 0.950)). The reduction though was accounted for by the bigger babies in the 32 0/7 to 33 6/7 weeks group as only 1 of 11 was intubated when given nebulized surfactant compared to 10 of 13 managed with CPAP.  The duration of ventilation in the first 72 hours was not different between the groups: the median (range) 0 (0–62) hour for the nebulization group and 9 (0–64) hours for the control group (p=0.220).  It is important in seeing these results that the clinicians deciding whether infants should be intubated for surfactant administration were blind to the arm the infants were in.  All administration of curosurf via nebulization or sham procedures were done behind a screen. The total number of infants randomized were 66 so they did fall shy of the necessary recruitment but since they did find a difference the results seem valid.  Importantly, there were no differences in complications although I can’t be totally confident there really is no risk as this study was grossly underpowered to look at rarer outcomes. Breaking down the results This study has me excited as what it shows is that “it kind of works“.  Why would larger babies be the ones to benefit the most?  My guess is that some but not a lot of surfactant administered via nebulization reaches the alveoli.  Infants with lesser degrees of surfactant deficiency (32 0/7 to 33 6/7) weeks might get just enough to manage without an endotracheal tube.  Those infants (in particular less than 32 0/7 weeks) who have more significant surfactant deficiency don’t get enough and therefore are intubated.  Supporting this notion is the overall delay in time to intubation in those who were intubated despite nebulization (11.6 hours in the nebulization group vs 4.9 hours in the control arm).  They likely received some deposition in the distal alveoli but not enough to completely stave off an endotracheal tube. One concerning point from the study though had to do with the group of infants who were intubated despite nebulization of surfactant.  When you look at total duration of ventilation (hours) it was 14.6 (9.0–24.8) in the control arm vs 25.4 (14.6–42.2) p= 0.029*.  In other words infants who were intubated in the end spent about twice as long intubated as those who were intubated straight away.  Not a huge concern if you are born at 32 weeks or more but those additional thousands of positive pressure breaths are more worrisome as a risk for CLD down the road. As it stands, if you had an infant who was 33 weeks and grunting with an FiO2 of 35% might you try this if you could get your hands on the nebulizer?  It appears to work so the only question is whether you are confident enough that the risk of such things as pneumothorax or IVH isn’t higher if intubation is delayed.  It will be interesting to see if this gets adopted at this point. The future no doubt will see a refinement of the nebulizer and an attempt to see how well this technique works in infants below 29 weeks.  It is in this group though that prolonging time intubated would be more worrisome.  I don’t want to dismiss this outright as I see this as a pilot study that will lead the way for future work that will refine this technique.  If we get this right this would be really transformative to Neonatology and just might be the next big leap.

AllThingsNeonatal

AllThingsNeonatal

 

Apgar score of 0 at 10 minutes: Why the new NRP recommendations missed the mark.

Originally posted at: https://winnipegneonatal.wordpress.com/ Facebook Page: https://www.facebook.com/allthingsneonatal/ As I read through the new NRP recommendations and began posting interesting points on my Facebook Page I came across a section which has left me a little uneasy. With respect to a newborn 36 weeks and above who is born asystolic and by ten minutes of age continues to remain so and has an apgar score of zero the recommendation that has been put forward is this: An Apgar score of 0 at 10 minutes is a strong predictor of mortality and morbidity in late-preterm and term infants.  We suggest that, in babies with an Apgar score of 0 after 10 minutes of resuscitation, if the heart rate remains undetectable, it may be reasonable to stop resuscitation; however, the decision to continue or discontinue resuscitative efforts should be individualized. Variables to be considered may include whether the resuscitation was considered to be optimal, availability of advanced neonatal care, such as therapeutic hypothermia, specific circumstances before delivery (eg, known timing of the insult), and wishes expressed by the family (weak recommendation, very-low-quality evidence). There are some significant problems with this part of the statement. They claim that the apgar score at ten minutes is a strong predictor but when you look at the analysis of the evidence presented in the body of the paper it is weak at best.  I am not clear how one declares the prediction is strong in the face of poor evidence but I will acknowledge intuitively that this makes some sense but do challenge them on the use of the word "strong". 2.  They are correct in acknowledging that the introduction of hypothermia in such settings has changed the landscape in as much as I find it quite difficult to prognosticate unless a child is truly moribund after resuscitation.  Given such uncertainty it is concerning to me that this recommendation may be committed to memory incorrectly in some places that do have access to cooling and may be used more rigidly as though shalt stop at 10 minutes. 3.  In the middle of a resuscitation it is quite difficult to process all of the facts pertaining to a particular newborn while orders for chest compressions, emergency UVCs and epinephrine are being given.  Can we really individualize within ten minutes accurately and take the families wishes truly into account?  This just does not seem practical. 4.  The families wishes are taken into account but inserted as a "weak recommendation".  How can the wishes of the family in any family centred model of care be minimized in such a way even if we believe the situation to be dire? 5.  Since the introduction of hypothermia there appears to be a near 50% survival rate in such newborns and as the authors state 27% of survivors who received cooling had no moderate or severe disability.  Here in lies my greatest issue with this guideline and that is the hypocrisy this position takes when you compare populations at 23 and 24 weeks gestational age.  Survival at these GA in the recent NEJM study of almost 5000 preterm infants under 27 weeks were 33 and 57 % respectively at 23 & 24 weeks with rates of survival without moderate or severe disability being 16 and 31% in the two groups.  The fallout from this and other studies at the extremes of gestational age have been that we should be more aggressive as the outcomes are not as bad as one would predict.  How can we argue this for the 23-24 week infants and for term infant with the same likelihood of outcomes we would unilaterally stop in many centres?! So Now What Do We Do? We are supposed to be practising family centred care and much like the argument at the edge of viability the same should apply here.  The wishes of the family should never be minimized.  Arguably it may be very difficult in such an unexpected scenario to appraise a family of the situation and have clarity around the issue but if a heart rate can be restored after a few more minutes do we not owe it to the family and the child to bring the infant back to the NICU and see what transpires especially if cooling is available? The million dollar question of course is where do we draw the line?  No heart rate at 15, 20 minutes?  Based on the evidence thus far it seems to me that a little longer than 10 minutes is reasonable especially in well equipped centres with access to cooling and modern ventilation and treatments for pulmonary hypertension.  How long though must be individualized and should be determined in partnership with the team caring for the patient which must include the family.

AllThingsNeonatal

AllThingsNeonatal

 

Dextrose gel for hypoglycemia: Safe in the long run?

The Sugar Babies trial was the subject of a post earlier this year as the largest trial to date examining the effects of using dextrose gel to treat hypoglycemia.  For an analysis of the use of gel in this situation please see the original post Glucose Gel For Neonatal Hypoglycemia: Can We Afford Not To Use It? In summary though, the trial involved 118 infants who received 40% dextrose gel vs 119 who received a placebo gel. All of the infants in this study were selected based on risk factors for hypoglycemia (IDM, IUGR, LBW, LGA, near term) and were all 35 weeks or greater. Each infant had to be less than 48 hours of age when enrolled. Infants received 0.5 mL/kg 40% dextrose gel (200 mg/kg). This was designed to deliver the same amount of sugar as would be given with a D10W bolus of 2 mL/kg. In order to receive the treatment the blood glucose had to be < 2.6 mmol/L so equivalent to our own standards in Canada and the US. Treatment failure, which was the primary outcome was defined as a blood glucose < 2.6 mmol/L despite two treatments with gel.  The studies most important findings were a reduction in NICU admission and greater breastfeeding rates at 2 weeks of age (due to avoidance of formula feeding to keep the glucose stable). But Is It Safe? With any new strategy though, questions arise regarding safety of the product in the long term.  As one reader commented after the original post, could the red dye be harmful in some way or perhaps some other constituent of the gel?  The authors of the original study have now published the follow-up paper entitled Outcome at 2 Years after Dextrose Gel Treatment for Neonatal Hypoglycemia: Follow-Up of a Randomized Trial.  The findings were a little concerning to me in that there was a high rate of neurosensory impairment in both arms (sham and glucose gel) with the following findings.  None of the differences were significant however. Looking at these results you could be dismayed that the glucose gel did not show any benefit compared to standard therapies for hypoglycemia but if you look at the original study one could equally ask why would we have expected it to? Should The Results Surprise Us? All of the newborns in either arm had an episode of hypoglycemia recorded in order to qualify for entry into the study.  The glucose gel was effective compared to placebo in reducing admissions and increasing breastfeeding rates (which one might think would improve outcomes) but we don't know what the drop off rate in breastfeeding was after 2 weeks. What I can say though is that if there were significant adverse side effects with the glucose gel I would have expected to see some differences in outcome favouring the placebo group which did not occur. An additional issue is we know that the placebo group had more treatment failures meaning they would have had more newborns in the original study with a second low glucose.  Would this favour a worse outcome in the placebo group?  If so does the equivalence in groups suggest that the dextrose gel might worsen outcomes? Unfortunately, what this study is really missing is some indication of how low and how long the blood sugars remained under 2.6 mmol/L in both arms of the study.  We know the mean low glucoses were similar but what about duration and range? While the rates of mild, moderate and severe impairment are the same we don't know how severe the hypoglycemia was which if unbalanced between the groups could actually lead to very different conclusions here.  For example, let's say the glucose gel group had an over representation of infants with 3 or more episodes of hypoglycemia compared to the placebo arm.  The fact that the outcomes are equivalent would suggest that the glucose gel is in fact protective. What Can We Say? I suspect that while glucose gel is effective, to truly assess harm across many different aspects of development we will need larger sample sizes.  We also have to take the results of this study with a grain of salt as so many that have come before it have seen outcomes at school age reveal different findings than when assessed at 2 years of age as in this study. From my standpoint though I will continue to advocate for the use of glucose gel as the reduction in NICU admissions and enhancement of breastfeeding rates especially if sustained are well worth the efforts to implement this strategy if you aren't using it already.

AllThingsNeonatal

AllThingsNeonatal

 

Does High Flow Really Have A Place in the NICU At All?

This may sound familiar as I wrote about this topic in the last year but the previous post was restricted to infants who were under 1000g.  High Flow Nasal Cannula be careful out there had a main message that suggested the combined outcome of BPD or death was more prevalent when HFNC is used alone or with CPAP than when CPAP is used alone.  The question remains though whether this applies to larger infants.  Without looking at the evidence for that combined outcome most people would say there is unlikely to be a difference.  Larger more mature babies have a much lower risk of BPD or death so proponents of HFNC would say it is simpler to use and helps prevent nasal breakdown as well.  The question remains as to whether all outcomes are the same in larger infants and that is the point of this post. A Non-Inferiority Trial First off it is important to understand what this type of trial is.  The first requirement is that the two treatments have both been compared to a placebo and found to be both effective.  Once you establish that you have a choice between two treatment options then you eliminate the placebo and compare them head to head.  What you are looking for in this type of trial is to determine not whether one is better than the other but that there is no difference in a clinical outcome of interest.  If you find no difference then the next step is to look at other outcomes that might be of interest and see if there are any benefits to picking one versus the other.  In the case of CPAP vs HNFC, if a non-inferiority trial showed no difference in an important outcome such as length of stay but nasal breakdown was less with HFNC it might lead a unit to use HFNC for their infants.  Okay, now that we have that cleared up we can move on to an actual study examining this very subject. Nasal High-Flow Therapy for Primary Respiratory Support in Preterm Infants. This was an interesting study with a great name (The HIPSTER trial) that enrolled infants > 28 weeks and 0 days with none of the infants receiving surfactant but either being randomized to HFNC or CPAP after delivery.  These infants were your typical modern day cohort of babies who may avoid intubation and surfactant by establishing FRC early with positive pressure applied to the nose through one of these devices.  The end point for the study was treatment failure within 72 hours.  If an infant failed in the HFNC they could have a trial of CPAP whereas in the CPAP group they were intubated.  For each infant in the HFNC group flow was set from 6-8 l/min and for CPAP 6-8 cmH2O. Treatment was considered to have failed if an infant receiving maximal support (high-flow therapy at a gas flow of 8 liters per minute or CPAP at a pressure of 8 cm of water) met one or more of the following criteria: FiO2 of 0.4 or higher Arterial or free flowing cap gas with a pH of 7.2 or less plus a pCO2 > 60 mm Hg obtained at least 1 hour after starting treatment Two or more episodes of apnea requiring positive-pressure ventilation within a 24-hour period or six or more episodes requiring any intervention within a 6-hour period. Infants with an urgent need for intubation and mechanical ventilation. So what happened? The trial randomized 583 infants (278 HFNC, 286 CPAP) but was halted by the data and safety monitoring committee after an analysis of the first 515 revealed that the outcome was worse in the HFNC group (25.5% failure rate vs 13.3 for CPAP).  Interestingly treatment failures were more common in babies below and above 32 weeks so it was not just the smallest infants who failed. Another interesting finding was that the most common reason for treatment failure was criteria 1 (FiO2 > 40%) while intubation was higher for all infants but did not reach statistical significance.  Curiously what did reach a significant difference was criteria #4 (18.4% urgent intubations in the CPAP group vs 5.6% in the HFNC group). You might be tempted to therefore ponder which is worse, a little O2 or being intubated but you need to recall the trial design which was set up to provide this kind of result.  If you failed HFNC you were placed on CPAP whereas if you failed CPAP you were intubated.  In the HFNC group, 78 infants were deemed to have failed but 28 of them were in fact “rescued by CPAP”.  It therefore isn’t a fair comparison when it comes to urgent intubation since if you failed CPAP there wasn’t another option. Not a total loss Nasal trauma was indeed much lower in the HFNC group, occurring only 8.3% vs 18.5% of the time with CPAP.  Pneumothorax was also found to be significantly different with none of the patients in the HFNC group having that complication vs 2.1% in the CPAP group.  What this study tells us is that as a primary modality to treat newborns with RDS who have not received surfactant it is preferable to use CPAP in the first 72 hours.  Some of you may say it might not say that at all but consider the impact of having more babies exposed to high FiO2.  We know from other studies that high FiO2 can be quite damaging to preterm infants and this study was certainly not powered to look at all those important outcomes such as ROP, PVL and BPD.  The authors report them and found no difference but without adequate power to show a difference I wouldn’t take much comfort in those findings. I think were things may settle out though is what to do in more mature infants.  There is no question that for those on chronic respiratory support there is some risk of nasal breakdown.  Although I don’t have much experience with HFNC I would think that for the older patient who either already has BPD at 36 weeks or is close to that point but reliant on +4 or +5 CPAP that HFNC might help “give them a break”.  As such I don’t see this as a total loss but rather an option to try when CPAP for whatever reason is not tolerated. As a primary therapy for non-invasive management RDS I will keep my CPAP for all babies thank you.

AllThingsNeonatal

AllThingsNeonatal

 

Perhaps it is time to change the way we use caffeine in the NICU.

This has been a question that has befuddled Neonatologists for years.  Get ten of us in a room and you will get a variety of responses ranging from (talking about caffeine base) 2.5 mg/kg/day to 10 mg/kg/day.  We will espouse all of our reasons and question the issue of safety at higher doses but in the end do we really know?  As I was speaking to a colleague in Calgary yesterday we talked about how convinced we are of our current management strategies but how we both recognize that half of what we think we know today we will be questioning in 10 years.  So how convinced should we really be about caffeine? Even the Cochrane Review Suggests There Is Something Amiss Back in 2010 the Cochrane Collaboration examining 6 trials on caffeine for treating apnea of prematurity concluded “Methylxanthine is effective in reducing the number of apnoeic attacks and the use of mechanical ventilation in the two to seven days after starting treatment.” Notice the bolded section.  Two to seven days.  Interesting that we don’t see the effect last in perpetuity.  Why might that be?  Do babies become resistant with time or is there a change in the way these infants metabolize the drug such that levels in the bloodstream drop after that time point.  It is almost certainly the latter and in the last 7 years have we really seen any response to this finding?  I would say no for the most part although I don’t work in your unit so hard to say for sure. At least where I practice we pick a dose somewhere between 2.5-5 mg/kg/day and give a load of 10 mg/kg when we start the drug.  From time to time we give a miniload of 5 mg/kg and may or may not increase the dose of maintenance based on the number of apneic events the babies are having.  What if we could be proactive instead of reactive though.  Do the babies need to have multiple events before we act or could we prevent the events from happening at all? Proactive Treatment With Caffeine We have known that caffeine clearance increases with postnatal age.  The half-life of the drug shortens from about a week at the earliest gestational ages to 2-2.5 days by term equivalent age.  For those infants who are older such as 32 weeks and above we expect them to be off caffeine (if they need it) within 2-3 weeks so I am not really talking about them but what about the babies born earlier than that or certainly MUCH earlier at 23 and 24 weeks who will be on caffeine possibly till term.  Should one size (dose) fit all?  No it really shouldn’t and some crafty researchers led by Koch G have published a paper that demonstrates why entitled Caffeine Citrate Dosing Adjustments to Assure Stable Caffeine Concentrations in Preterm Neonates. In this paper the authors armed with knowledge of the half life of caffeine at different gestational ages were able to calculate the clearance of the drug at different postnatal ages to demonstrate in a model of a 28 week male infant weighing 1150g. The authors further took into account predicted weight changes and were able to calculate what the expected caffeine levels would be in the fictional infant at various time points.  The target caffeine levels for this patient were a trough level of 15 -20 mg/L which are the currently acceptable ranges in the literature.  The testing was first done using a standard load of 10 mg/kg (base) followed by 5 mg/kg/d and demonstrated levels which yielded the following graph over time.    What this demonstrates is that if the dose is unchanged over the first 7 weeks, this hypothetical infant will only achieve effective concentrations for the first week.  Interesting isn’t it that the Cochrane review found clinical effect over the first 2-7 days? What if you were to double the dose to really “hit” the infant with a good dose of caffeine from the start and maintain at that level based on their weight gain as shown next. Well, you will get what you are hoping for and keep the trough level above 15 mg/L but you will hit 30 mg/L that some have said is too high and can lead to adverse effects (ever seen SVT with these high doses? I have).  Like Goldilocks and the Three Bears could there be a dosing strategy that might be just right?  The authors put in another model based on the knowledge of caffeine clearance over time and suggested a strategy in which after the first week the adjusted maintenance doses would be 3 mg/kg/day and 3.5 mg/kg/day in the third to fourth weeks and lastly 4 mg/kg/d in the 5th to 8th week.  Using that dosing schedule the model produced this curve. As you can see, the infant would have a therapeutic target without reaching levels above 30 mg/L and potential for side effects. As many of you read this however you may ask the obvious question. Each of us have seen infants who require higher doses than this to rid themselves of significant apnea and escape reintubation.  Given that this is a mathematical model it assumes that this fictional infant will respond beautifully to a trough level of 15 to 20 mg/L but some will not. Even in the curve shown it is clear that there is some room to go higher in the dosing as the curve is just touching 20 mg/L. A Suggestion For The Future What grabbed my attention here is the possibility that we could take a proactive rather than reactive approach to these infants.  Once a small baby is controlled on their dose of caffeine whether it is 2.5, 3, 5 or even 6 mg/kg/d of caffeine should we wait for more events to occur and then react by increasing caffeine?  What if we are too late to respond and the patient is intubated.  What effect does this have on the developing lung, what about the brain that is subjected to bradycardic events with resultant drops in cardiac output and cerebral perfusion.  Perhaps the solution is to work with our pharmacists and plan to increase dosing at several time points in the infants journey through the NICU even if they aren’t showing symptoms yet.  No doubt this is a change in approach at least for the unit I work in but one that should start with a conversation!    

AllThingsNeonatal

AllThingsNeonatal

 

Maybe we shouldn’t be in such a rush to stop caffeine.

Given that many preterm infants as they near term equivalent age are ready to go home it is common practice to discontinue caffeine sometime between 33-34 weeks PMA.  We do this as we try to time the readiness for discharge in terms of feeding, to the desire to see how infants fare off caffeine.  In general, most units I believe try to send babies home without caffeine so we do our best to judge the right timing in stopping this medication.  After a period of 5-7 days we generally declare the infant safe to be off caffeine and then move on to other issues preventing them from going home to their families.  This strategy generally works well for those infants who are born at later gestations but as Rhein LM et al demonstrated in their paper Effects of caffeine on intermittent hypoxia in infants born prematurely: a randomized clinical trial., after caffeine is stopped, the number of intermittent hypoxic (IH) events are not trivial between 35-39 weeks.  Caffeine it would seem may still offer some benefit to those infants who seem otherwise ready to discontinue the medication.  What the authors noted in this randomized controlled trial was that the difference caffeine made when continued past 34 weeks was limited to reducing these IH events only from 35-36 weeks but the effect didn’t last past that.  Why might that have been?  Well it could be that the babies after 36 weeks don’t have enough events to really show a difference or it could be that the dose of caffeine isn’t enough by that point.  The latter may well be the case as the metabolism of caffeine ramps up during later gestations and changes from a half life greater than a day in the smallest infants to many hours closer to term.  Maybe the caffeine just clears faster? Follow-up Study attempts to answer that very question. Recognizing the possibility that levels of caffeine were falling too low after 36 weeks the authors of the previous study begun anew to ask the same question but this time looking at caffeine levels in saliva to ensure that sufficient levels were obtained to demonstrate a difference in the outcome of frequency of IH.  In this study, they compared the original cohort of patients who did not receive caffeine after planned discontinuation (N=53) to 27 infants who were randomized to one of two caffeine treatments once the decision to stop caffeine was made.  Until 36 weeks PMA each patient was given a standard 10 mg/kg of caffeine case and then randomized to two different strategies.  The two dosing strategies were 14 mg/kg of caffeine citrate (equals 7 mg/kg of caffeine base) vs 20 mg/kg (10 mg/kg caffeine base) which both started once the patient reached 36 weeks in anticipation of increased clearance.  Salivary caffeine levels were measured just prior to stopping the usual dose of caffeine and then one week after starting 10 mg/kg dosing and then at 37 and 38 weeks respectively on the higher dosing.  Adequate serum levels are understood to be > 20 mcg/ml and salivary and plasma concentrations have been shown to have a high level of agreement previously so salivary measurement seems like a good approach.  Given that it was a small study it is work noting that the average age of the group that did not receive caffeine was 29.1 weeks compared to the caffeine groups at 27.9 weeks.  This becomes important in the context of the results in that earlier gestational age patients would be expected to have more apnea which is not what was observed suggesting a beneficial effect of caffeine even at this later gestational age.  Each patient was to be monitored with an oximeter until 40 weeks as per unit guidelines. So does caffeine make a difference once term gestation is reached? A total of 32 infants were enrolled with 12 infants receiving the 14 mg/kg and 14 the 20 mg/kg dosing.  All infants irrespective of assigned group had caffeine concentrations above 20 mcg/mL ensuring that a therapeutic dose had been received.  The intent had been to look at babies out to 40 weeks with pulse oximetry even when discharged but owing to drop off in compliance with monitoring for a minimum of 10 hours per PMA week the analysis was restricted to infants at 37 and 38 weeks which still meant extension past 36 weeks as had been looked at already in the previous study.  The design of this study then compared infants receiving known therapeutic dosing at this GA range with a previous cohort from the last study that did not receive caffeine after clinicians had determined it was no longer needed. The outcomes here were measured in seconds per 24 hours of intermittent hypoxia (An IH event was defined as a decrease in SaO2 by ⩾ 10% from baseline and lasting for ⩾5 s).  For graphical purposes the authors chose to display the number of seconds oxygen saturation fell below 90% per day and grouped the two caffeine patients together given that the salivary levels in both were therapeutic.  As shown a significant difference in events was seen at all gestational ages. Putting it into context The scale used I find interesting and I can’t help but wonder if it was done intentionally to provide impact.  The outcome here is measured in seconds and when you are speaking about a mean of 1200 vs 600 seconds it sounds very dramatic but changing that into minutes you are talking about 20 vs 10 minutes a day.  Even allowing for the interquartile ranges it really is not more than 50 minutes of saturation less than 90% at 36 weeks.  The difference of course as you increase in gestation becomes less as well.  When looking at the amount of time spent under 80% for the groups at the three different gestational ages there is still a difference but the amount of time at 36, 27 and 38 weeks was 229, 118 and 84 seconds respectively without caffeine (about 4, 2 and 1 minute per day respectively) vs 83, 41, and 22 seconds in the caffeine groups. I can’t help but think this is a case of statistical significance with questionable clinical significance.  The authors don’t indicate that any patients were readmitted with “blue spells” who were being monitored at home which then leaves the sole question in my mind being “Do these brief periods of hypoxemia matter?”  In the absence of a long-term follow-up study I would have to say I don’t know but while I have always been a fan of caffeine I am just not sure. Should we be in a rush to stop caffeine?  Well, given that the long term results of the CAP study suggest the drug is safe in the preterm population I would suggest there is no reason to be concerned about continuing caffeine a little longer. If the goal is getting patients home and discharging on caffeine is something you are comfortable with then continuing past 35 weeks is something that may have clinical impact.  At the very least I remain comfortable in my own practice of not being in a rush to stop this medication and on occasion sending a patient home with it as well.    

AllThingsNeonatal

AllThingsNeonatal

 

Gentle ventilation must start from birth

The lungs of a preterm infant are so fragile that over time pressure limited time cycled ventilation has given way to volume guaranteed (VG) or at least measured breaths.  It really hasn’t been that long that this has been in vogue.  As a fellow I moved from one program that only used VG modes to another program where VG may as well have been a four letter word.  With time and some good research it has become evident that minimizing excessive tidal volumes by controlling the volume provided with each breath is the way to go in the NICU and was the subject of a Cochrane review entitled Volume-targeted versus pressure-limited ventilation in neonates. In case you missed it, the highlights are that neonates ventilated with volume instead of pressure limits had reduced rates of: death or BPD pneumothoraces hypocarbia severe cranial ultrasound pathologies duration of ventilation These are all outcomes that matter greatly but the question is would starting this approach earlier make an even bigger difference? Volume Ventilation In The Delivery Room I was taught a long time ago that overdistending the lungs of an ELBW in the first few breaths can make the difference between a baby who extubates quickly and one who goes onto have terribly scarred lungs and a reliance on ventilation for a protracted period of time.  How do we ventilate the newborn though?  Some use a self inflating bag, others an anaesthesia bag and still others a t-piece resuscitator.  In each case one either attempts to deliver a PIP using the sensitivity of their hand or sets a pressure as with a t-piece resuscitator and hopes that the delivered volume gets into the lungs.   The question though is how much are we giving when we do that? High or Low – Does it make a difference to rates of IVH? One of my favourite groups in Edmonton recently published the following paper; Impact of delivered tidal volume on the occurrence of intraventricular haemorrhage in preterm infants during positive pressure ventilation in the delivery room. This prospective study used a t-piece resuscitator with a flow sensor attached that was able to calculate the volume of each breath delivered over 120 seconds to babies born at < 29 weeks who required support for that duration.  In each case the pressure was set at 24 for  PIP and +6 for PEEP.  The question on the authors’ minds was that all other things being equal (baseline characteristics of the two groups were the same) would 41 infants given a mean volume < 6 ml/kg have less IVH compared to the larger group of 124 with a mean Vt of > 6 ml/kg.  Before getting into the results, the median numbers for each group were 5.3 and 8.7 mL/kg respectively for the low and high groups.  The higher group having a median quite different than the mean suggests the distribution of values was skewed to the left meaning a greater number of babies were ventilated with lower values but that some ones with higher values dragged the median up. Results IVH < 6 mL/kg > 6 ml/kg p 1 5% 48%   2 2% 13%   3 0 5%   4 5% 35%   Grade 3 or 4 6% 27% 0.01 All grades 12% 51% 0.008 Let’s be fair though and acknowledge that much can happen from the time a patient leaves the delivery room until the time of their head ultrasounds.  The authors did a reasonable job though of accounting for these things by looking at such variables as NIRS cerebral oxygenation readings, blood pressures, rates of prophylactic indomethacin use all of which might be expected to influence rates of IVH and none were different.  The message regardless from this study is that excessive tidal volume delivered after delivery is likely harmful.  The problem now is what to do about it? The Quandry Unless I am mistaken there isn’t a volume regulated bag-mask device that we can turn to to control delivered tidal volume.  Given that all the babies were treated the same with the same pressures I have to believe that the babies with stiffer lungs responded less in terms of lung expansion so in essence the worse the baby, the better they did in the long run at least from the IVH standpoint.  The babies with the more compliant lungs may have suffered from being “too good”.  Getting a good seal and providing good breaths with a BVM takes a lot of skill and practice.  This is why the t-piece resuscitator grew in popularity so quickly.  If you can turn a couple dials and place it over the mouth and nose of a baby you can ventilate a newborn.  The challenge though is that there is no feedback.  How much volume are you giving when you start with the same settings for everyone?  What may seem easy is actually quite complicated in terms of knowing what we are truly delivering to the patient.  I would put to you that someone far smarter than I needs to develop a commercially available BVM device with real time feedback on delivered volume rather than pressure.  Being able to adjust our pressure settings whether they be manual or set on a device is needed and fast! Perhaps someone reading this might whisper in the ear of an engineer somewhere and figure out how to do this in a device that is low enough cost for everyday use.    

AllThingsNeonatal

AllThingsNeonatal

 

Capnography or colorimetric detection of CO2 in the delivery suite. What to choose?

For almost a decade now confirmation of intubation is to be done using detection of exhaled CO2. The 7th Edition of NRP has the following to say about confirmation of ETT placement “The primary methods of confirming endotracheal tube placement within the trachea are detecting exhaled CO2 and a rapidly rising heart rate.” They further acknowledge that there are two options for determining the presence of CO2 “There are 2 types of CO2 detectors available. Colorimetric devices change color in the presence of CO2. These are the most commonly used devices in the delivery room. Capnographs are electronic monitors that display the CO2 concentration with each breath.” The NRP program stops short of recommending one versus the other. I don’t have access to the costs of the colorimetric detectors but I would imagine they are MUCH cheaper than the equipment and sensors required to perform capnography using the NM3 monitor as an example. The real question though is if capnography is truly better and might change practice and create a safer resuscitation, is it the way to go? Fast but not fast enough? So we have a direct comparison to look at. Hunt KA st al published Detection of exhaled carbon dioxide following intubation during resuscitation at delivery this month. They started from the standpoint of knowing from the manufacturer of the Pedicap that it takes a partial pressure of CO2 of 4 mm Hg to begin seeing a colour change from purple to yellow but only when the CO2 reaches 15 mm Hg do you see a consistent colour change with that device. The capnograph from the NM3 monitor on the other hand is quantitative so is able to accurately display when those two thresholds are reached. This allowed the group to compare how long it took to see the first colour change compared to any detection of CO2 and then at the 4 and 15 mm Hg levels to see which is the quicker method of detection. It is an interesting question as what would happen if you were in a resuscitation and the person intubates and swears that they are in but there is no colour change for 5, 10 or 15 seconds or longer? At what point do you pull the ETT? Compare that with a quantitative method in which there is CO2 present but it is lower than 4. Would you leave the tube in and use more pressure (either PIP/PEEP or both?)? Before looking at the results, it will not shock you that ANY CO2 should be detected faster than two thresholds but does it make a difference to your resuscitation? The Head to Head Comparison The study was done retrospectively for 64 infants with a confirmed intubation using the NM3 monitor and capnography.  Notably the centre did not use a colorimetric detector as a comparison group but rather relied on the manufacturers data indicating the 4 and 15 mm Hg thresholds for colour changes.  The mean age of patients intubated was 27 weeks with a range of 23 – 34 weeks.  The results I believe show something quite interesting and informative.   Median time secs (range) Earliest CO2 detection 3.7 (0 – 44s) 4 mm Hg 5.3 (0 – 727) 15 mm Hg 8.1 (0 – 727) I wouldn’t worry too much about a difference of 1.6 seconds to start getting a colour change but it is the range that has me a little worried.  The vast majority of the patients demonstrated a level of 4 or 15 mm Hg within 50 seconds although many were found to take 25-50 seconds.  When compared to a highest level of 44 seconds in the first detection of CO2 group it leads one to scratch their head.  How many times have you been in a resuscitation and with no CO2 change you keep the ETT in past 25 seconds?  Looking closer at the patients, there were 12 patients that took more than 30 seconds to reach a threshold of 4 mm Hg.  All but one of the patients had a heart rate in between 60-85.  Additionally there was an inverse relationship found between gestational age and time to detection.  In other words, the smallest of the babies in the study took the longest to establish the threshold of 4 and 15 mm Hg. Putting it into context? What this study tells me is that the most fragile of infants may take the longest time to register a colour change using the colorimetric devices.  It may well be that these infants take longer to open up their pulmonary vasculature and deliver CO2 to the alveoli.  As well these same infants may take longer to open the lung and exhale the CO2.  I suppose I worry that when a resuscitation is not going well and an infant at 25 weeks is bradycardic and being given PPV through an ETT without colour change, are they really not intubated?  In our own centre we use capnometry in these infants (looks for a wave form of CO2) which may be the best option if you are looking to avoid purchasing equipment for quantitative CO2 measurements.  I do worry though that in places where the colorimetric devices are used for all there will be patients who are extubated due to the thought that they in fact have an esophageal intubation when the truth is they just need time to get the CO2 high enough to register a change in colour. Anyways, this is food for thought and a chance to look at your own practice and see if it is in need of a tweak…

AllThingsNeonatal

AllThingsNeonatal

 

Does size really matter when weaning from an incubator?

Look around an NICU and you will see many infants living in incubators. All will eventually graduate to a bassinet or crib but the question always is when should that happen? The decision is usually left to nursing but I find myself often asking if a baby can be taken out. My motivation is fairly simple. Parents can more easily see and interact with their baby when they are out of the incubator. Removing the sense of “don’t touch” that exists for babies in the incubators might have the psychological benefit of encouraging more breastfeeding and kangaroo care. Both good things. Making the leap For ELBW and VLBW infants humidity is required then of course they need this climate controlled environment. Typically once this is no longer needed units will generally try infants out of the incubator when the temperature in the “house” is reduced to 28 degrees. Still though, it is not uncommon to hear that an infant is “too small”. Where is the threshold though that defines being too small? Past research studies have looked at two points of 1600 vs 1800g for the smallest of infants. One of these studies was a Cochrane review by New K, Flenady V, Davies MW. Transfer of preterm infants for incubator to open cot at lower versus higher body weight. Cochrane Database Syst Rev 2011;(9). This concluded that early transition was safe for former ELBWs at the 1600g weight cut off. What about the majority of our babies? While the ELBW group takes up a considerable amount of energy and resources the later preterm infants from 29 to 33 6/7 weeks are a much larger group of babies. How safe is this transition for this group at these weights? Shankaran et al from the NICHD published an RCT on this topic recently; Weaning of Moderately Preterm Infants from the Incubator to the Crib: A Randomized Clinical Trial. The study enrolled Infants in this gestational age range with a birth weight <1600g were randomly assigned to a weaning weight of 1600 or 1800 g. Within 60 to 100 g of weaning weight, the incubator temperature was decreased by 1.0°C to 1.5°C every 24 hours until 28.0°C. Weaning to the crib occurred when axillary temperatures were maintained 36.5°C to 37.4°C for 8 to 12 hours. Clothing and bedcoverings were standardized. The primary outcome was LOS from birth to discharge. What did they find? A total of 366 babies were enrolled (187 at 1600g and 179 at 1800g. Baseline characteristics of the two groups revealed no statistical differences. Mean LOPS was a median of 43 days in the lower and 41 days in the higher weight group (P = .12). After transition to a crib weight gain was better in the lower weight group, 13.7 g/kg/day vs 12.8 g/kg/ day (P = .005). Tracking of adverse events such as the incidence of severe hypothermia did not differ between groups. The only real significant difference was a better likelihood of weaning from the incubator in the higher group at 98% success vs 92% on the first attempt. Putting. That in perspective though, a 92% success rate by my standards is high enough to make an attempt worthwhile!   Concluding thoughts The authors have essentially shown that whether you wean at the higher or lower weight threshold your chances of success are pretty much the same. Curiously, weight gain after weaning was improved which seems counter intuitive. I would have thought that these infants would have to work extra hard metabolically to maintain their temperature and have a lower weight gain but that was not the case. Interestingly, this finding has been shown in another study as well; New K, Flint A, Bogossian F, East C, Davies MW. Transferring preterm infants from incubators to open cots at 1600 g: a multicentre randomised controlled trial. Arch Dis Child Fetal Neonatal Ed 2012;97:F88-92. Metabolic rate has been shown to increase in these infants but skin fold thickness has been shown to increase as well in infants moved to a crib. How these two things go together is a little beyond me as I would have thought that as metabolic rate increases storage of tissue would slow. Not apparently the case but perhaps just another example of the bodies ability to overcome challenges when put in difficult situations. A case maybe of “what doesn’t kill you makes you stronger?” The authors do point out that the intervention was unmasked but the standardization of weaning procedure and garments used in the cribs should have overcome that. There were 36% of parents who did not consent to the study so their inclusion could have swayed the results perhaps but the sample size here was large despite that. That the final results agree with findings in ELBW infants suggests that the results are plausible. What I think this study does though is tell us overall that weaning at a smaller weight is at least alright to try once one is at minimal settings in an incubator. Will this change your units practice? It is something that at least merits discussion.  

AllThingsNeonatal

AllThingsNeonatal

 

Why do we keep treating reflux in preemies?

Choosing wisely is an initiative to “identify tests or procedures commonly used whose necessity should be questioned and discussed with patients. The goal of the campaign is to reduce waste in the health care system and avoid risks associated with unnecessary treatment.” The AAP Section on Perinatal Pediatrics puts the following forth as one of their recommendations. “Avoid routine use of anti-reflux medications for treatment of symptomatic gastroesophageal reflux disease (GERD) or for treatment of apnea and desaturation in preterm infants. Gastroesophageal reflux is normal in infants. There is minimal evidence that reflux causes apnea and desaturation. Similarly, there is little scientific support for the use of H2 antagonists, proton-pump inhibitors, and motility agents for the treatment of symptomatic reflux. Importantly, several studies show that their use may have adverse physiologic effects as well as an association with necrotizing enterocolitis, infection and, possibly, intraventricular hemorrhage and mortality.” How strong is the evidence? The evidence for risk with acid suppression is largely based on either retrospective or in the case of Terrin G et al a prospective observational cohort study Ranitidine is Associated With Infections, Necrotizing Enterocolitis, and Fatal Outcome in Newborns.  In this study the authors compared a group of premature infants with birth weights between 401 – 1500g or 24 – 32 weeks gestation who received ranitidine for reflux symptoms to those who did not.  All told 91 were exposed while 183 were not.  The authors are to be commended for standardizing the feeding protocol in the study so that when comparing NEC between groups one could not blame differences in formula consumption or rate of feeding advancement.  Additionally, bias was controlled by having those not involved in care collect outcome data without knowing the purpose of the study.  Having said that, they may have been able to ascertain that ranitidine was used and have been influenced in their assessments. The patients in terms of risk factors for poor outcome including CRIB and apgar scores, PDA etc were no different to explain an increased risk for adverse outcome. From the above table, rates of infections were clearly higher in the ranitidine group but more concerning was the higher rate of mortality at 9.9% vs 1.6% P=0.003 and longer hospitalization median 52 vs 36 days P=0.001. Results of a Meta-Analysis Additional, evidence suggesting harm comes from a meta-analysis on the topic by More K, Association of Inhibitors of Gastric Acid Secretion and Higher Incidence of Necrotizing Enterocolitis in Preterm Very Low-Birth-Weight Infants.  This analysis actually includes the study by Terrin and only one other retrospective database study of 11072 patients by Guillet et al.  As the reviewers point out the study by Terrin while prospective did not employ the use of multiple regression to adjust for confounders while the larger study here did.  In the end the risk of NEC with the use of acid suppression was 1.78 (1.4 – 2.27; p<0.00001). What do we do with such evidence? I can say this much.  Although small in number, the studies that are available will make it very difficult to ever have a gold standard RCT done on this topic.  This scant amount of evidence, backed by the biologic plausibility that raising the gastric pH will lead to bacterial overgrowth and potential aspiration of such contents provides the support for the Choosing Wisely position. Why do we continue to see use of such medications though?  It is human nature I suspect that is the strongest motivator.  We care for infants and want to do our best to help them through their journey in neonatal units.  When we hear on rounds that the baby is “refluxing” which may be documented by gulping during a brady, visible spit ups during A&Bs or through auscultation hearing the contents in the pharynx we feel the need to do something.  The question invariably will be asked whether at the bedside or by the parents “Isn’t there something we can do?”. My answer to this is yes.  Wait for it to resolve on its own, especially when the premature infants are nowhere close to term.  I am not sure that there is any strong evidence to suggest treatment of reflux episodes with gastric acid suppression helps any outcomes at all and as we see from the Terrin study length of stay may be prolonged.  I am all in favour of positional changes to reduce such events but with respect to medications I would suggest we all sit on our hands and avoid writing the order for acid suppression.  Failure to do so will likely result in our hands being very busy for some infants as we write orders to manage NEC, pneumonia and bouts of sepsis.  

AllThingsNeonatal

AllThingsNeonatal

 

Partnering With Parents: One Size Does Not Fit All

Originally posted at: https://winnipegneonatal.wordpress.com/ Facebook Page: https://www.facebook.com/allthingsneonatal/ The journey from conception to the labour floor and then for some to the NICU is not a straight one.  There are times of joy, interspersed with sadness, denial, anger and eventually acceptance, as initial news of being pregnant leads to complications in pregnancy and then eventual admission of an infant to the NICU. Much has been said in recent years about the building of partnerships with parents and in fact there is a new catchphrase attached to the concept "shared decision making" (SDM).  There is no question that in the perfect world this is exactly the relationship that we should be striving for with all of our patients.  The world however is not perfect and although this may not be the most popular opinion I have given, I question how applicable this really is in many situations. A Reality Check Take for instance the parents who present to the labour floor of their local hospital in advanced labour at 24 weeks.  Proponents of this SDM model would suggest that a meeting take place and pertinent information be given to a family and together with the assistance of literature applicable to their situation (possibly a pamphlet) the health care providers and families come to a mutually agreeable decision as to what the best course of action is for them and their unborn infant.  This all sounds wonderful but examining the real life situation a little more closely is it actually reasonable to assume we can obtain this?  I have not been, nor will I ever be pregnant and certainly have never experienced contractions and felt the veil clouding my vision as the first dose of analgesia enters my veins to deal with the discomfort a woman experiences during labour.  Not to mention there are people admitting this couple, taking histories, establishing IV access, scanning bellies and a whole host of other pokes and prods along the way. My Role Better Defined Then I come in.  Among all this chaos I deliver the information, pass along a pamphlet and do the best job I can to inform said couple of the upcoming decision.  The trouble of course is how do we come to this mutual decision in the 15 - 30 minutes I spend with them during this crisis?  The answer sadly is we do our best but don't for a minute think that SDM has occurred.  I don't believe this is possible unless the family has prior experience with a preterm birth or perhaps is a HCP working with newborns or children with disabilities themselves.  In fact Boss RD et al in their own research on the subject identified that in hindsight religion, spirituality and hope are what motivated parents rather than what was said at the time.  In essence their minds are already made up.  It doesn't mean we shouldn't strive for the SDM but at least in my opinion, unless their contractions settle, a calmness ensues, they have time to digest the information being given and then meet again under less stressful circumstances, the SDM is a nice idea but for many not a reality. Shifting To The NICU I recall a significant moment in my training when I saw how the SDM model can actually cause more grief than help.  Dr. Keith Barrington a fellow blogger (if you haven't discovered him, his work is fascinating over at Neonatal Research) published one of the most impactful pieces of research of the decade during my fellowship.  The adverse neuro-developmental effects of postnatal steroids in the preterm infant: a systematic review of RCTs. Following this analysis there was a near moratorium on the use of post natal steroids.  The issue this created was that to now receive them you had to be close to the end of the limits of care.  At this point you either died (thereby concluding they are of no help) or you survived with disability that was due in part no doubt to how sick you had become (thereby concluding they are dangerous). The moment I am referring to was a conversation with a family in which the attending managing the unit presented the risks and benefits of postnatal steroids to the family when the FiO2 was at 40% one day.  The language used was non directive and the parents asked for another day to decide. The next day and each of the following two days they were unable to choose between giving the steroids and the perceived risk of brain damage versus not and watching the FiO2 climb by about 10% per day.  By the time the FiO2 several days later was at 80-90% they were distraught, teary and feeling helpless.  What they needed was direction; someone to give them some advice or more simply an educated opinion. We can strive to share in the decision making but I continue to believe there is a time and place to help our families by taking a stance or side.  We can equip them with as much information as we want but is there really any replacement for actually taking care of these infants, experiencing the ups and downs and hearing how they have done in follow-up? We simply can't expect the average parent to understand the true long term consequences of their decisions.  I am not saying we go back to a paternalistic time in medicine but I am saying that one size does not fit all. We owe it to our families to pursue SDM when we can but we have an equal obligation to recognize when this ideal state is simply not possible.  At this point we have to use the experiences and knowledge we have to provide them with the best advice we can.  We have gone through medical training, and gone down these paths so many times.  We can avoid biased opinion and rely on the facts as they are in our institutions but to not take a stand when it is needed at least for me is doing a disservice to those we are so eager to help.

AllThingsNeonatal

AllThingsNeonatal

 

A New Years Wish. Are We Up to It?

I have been at this writing thing for almost a year and as I was approaching the end of 2015 my thoughts turned to asking myself what I have learned.  There have been so many posts, in fact so many between the blog and Facebook posts that I have truly lost count.  Having said that the posts have generally fallen into two dominant categories; those promoting a therapy or diagnostic tool and those suggesting that we should avoid certain practices. If I had to have one wish though it would be that we could improve upon our diagnostic accuracy when it comes to treating suspected infections in the newborn.  As health care providers we have an extremely loud inner voice trying to tell us to minimize risk when it comes to missing a true bacterial infection.  On the other hand so much evidence has come forth in the last few years demonstrating that prolonging antibiotics beyond 48 hours is not just unwise in the absence of true infection but can be dangerous.  Increased rates of necrotizing enterocolitis is just one such example but other concerns due to interfering with the newborn microbiome have arisen in more recent years.  What follows are some general thoughts on septic workups that may help you (and myself in my own practice) as we move ahead into the New Year and may we cause less harm if we consider these. The Role of Paired Blood Cultures Although not published by our centre yet, we adopted this strategy for late onset sepsis a couple years back and have seen a significant reduction in work-ups deemed as true infections since adoption.  While the temptation to do only one blood culture is strong as we have a desire to minimize skin breaks consider how many more there will be if you do one culture and get a CONS organism back.  There will be several IV starts, perhaps a central line, repeat cultures etc.  If you had done two at the start and one was positive and the other negative you could avoid the whole mess as it was a contaminant from the start.  On my list of do no harms I think this may have the greatest benefit. The Chest X-Ray Can Be Your Friend While I am not a fan of routine chest x-rays I do believe that if you are prepared to diagnose an opacification on a chest x-ray as being due to a pneumonia (VAP or in those non-ventilated) that you need to follow this up with a repeat x-ray 24 - 48 hours later.  If the opacity is gone it was atelectasis as a true pneumonia will not clear that easily. Well worth the radiation exposure I say. If You Are Going To Do a Work-up Make It A Complete One We hear often in rounds the morning after a septic work-up that the baby was too sick to have an LP and that we can just check the CSF if the blood is positive.  There are two significant problems to this approach.  The first which is a significant concern is that in a recent study of patients with GBS meningitis, 20% of those who had GBS in the CSF had a negative blood culture.  Think about that one clearly... relying on a positive culture to decide to continue antibiotics may lead to partially treated GBS meningitis when you discontinue the antibiotics prematurely.  Not a good thing.  The second issue is that infants with true meningitis can have relatively low CSF WBC counts and may drift lower with treatment. Garges et al in a review of 95 neonates with true meninigits found that CSF WBC counts >21 cells per mm3 had a sensitivity of 79% and specificity at 81%.   This means that in those with true meningitis 19% of the time the WBC counts would be below 21 leading to the false impression that the CSF was "fine".  If antibiotics were effective it could well be by 48 hours that the negative CSF culture you find would incorrectly lead you to stop antibiotics.  Message:  Do the CSF sampling at the time of the septic work-up whenever possible. If We Aren't Prepared To Do a Supra Pubic Aspirate Should We Not Collect Urine At All? This provocative question was asked by a colleague last week and is based on the results of a study which was the topic of the following post: Bladder Catherterizations for UTI: Causing more harm than good?  The gist of it is that it would appear that in many cases the results of a catheter obtained urine cannot be trusted.  If that is the case then are we ultimately treating infections that don't actually exist when the only positive culture is from a urine.  I believe using point of care ultrasound to obtain specimens from a SPA will be the way to go but in the meantime how do we address the question of whether a UTI is present or not?  May need to rely on markers of inflammation such as a CRP or procalcitonin but that is not 100% sensitive or specific either but may be the best we have at the moment to determine how to interpret such situations. Lastly, Slow Down And Practice Good Hand Hygiene So much of what I said above is important when determining if an infection is present or not. The importance of preventing infection cannot be understated. Audits of hand hygiene practice more often than not demonstrate that physicians are a group with some of the lowest rates of compliance. Why is that? As a physician I think it has nothing to do with ignorance about how to properly perform the procedure but rather a tendency to rush from patient to patient in order to get all the things done that one needs to do well on service or call. If we all just slow down a little we may eventually have less need to run from patient to patient as the rate of infections may drop and with it demand for our time.  If slowing down is something that you too think is a good idea you may want to have a look at the book In Praise of Slowness by Carl Honore (TED Talk by Carl Below)  which may offer some guidance how to do something that is more easily said than done. Here is hoping for a little slower pace in the new year. We could reap some fairly large benefits! https://www.ted.com/talks/carl_honore_praises_slowness?language=en    

AllThingsNeonatal

AllThingsNeonatal

 

Giving surfactant through an LMA. Time to ditch the endotracheal tube?

In the spirit of full disclosure I have to admit I have never placed a laryngeal mask airway (LMA) in a newborn of any gestational age.  I have played with them in simulated environments and on many occasion mentioned that they are a great alternative to an ETT especially in those situations where intubation may not be possible due to the skill of the provider or the difficulty of the airway in the setting of micrognathia for example. In recent years though we have heard of examples of surfactant delivery via these same devices although typically these were only case reports. More recently a small randomized study of 26 infants by Attridge et al demonstrated in the group randomized to surfactant administration through an LMA that oxygen requirements were reduced after dosing.  This small pilot provides sufficient evidence to show that it is possible to provide surfactant and that at least some gets into the airway of the newborn.  This proof of concept though while interesting, did not answer the question of whether such delivery of surfactant would be the same or better than through an ETT.  As readers of my blog posts know, my usual stance on things is that the less invasive the better and as I look through the literature, I am drawn to concepts such as this to see if they can be added to our toolbox of non or less invasive strategies in the newborn. A Minimally Invasive Technique For The Masses? This past month, a small study by Pinheiro et al sought to answer this question by using 61 newborns between 29 0/7 - 36 6/7 weeks and greater than 1000g and randomizing them to either surfactant via the INSURE technique or LMA.  I cannot stress enough so will get it out of the way at the start that this strategy is not for those <1000g as the LMA is not designed to fit them properly and the results (to be shown) should not be generalized to this population. Furthermore then study included only those infants who needed surfactant between 4 - 48 hours of age, were on CPAP of at least 5 cm H2O and were receiving FiO2 between 30 - 60%.  All infants given surfactant via the insure technique were premedicated with atropine and morphine while those having an LMA received atropine only.  The primary outcome of the study was need for subsequent intubation or naloxone within 1 hour of surfactant administration.  The study was stopped early after an interim analysis (done as the fellow involved was finishing their fellowship - on a side note I find this an odd reason to stop) demonstrated better outcomes in the group randomized to the LMA. Before we get into the results let's address the possible shortcomings of the study as they might already be bouncing around your heads.  This study could not be blinded and therefore there could be a significant bias to the results.  The authors did have predetermined criteria for reintubation and although not presented, indicate that those participating stuck to these criteria so we may have to acknowledge they did the best they could here.  Secondly the study did not reach their numbers for enrolment based on their power calculation.  This may be ok though as they found a difference which is significant.  If they had found no difference I don't think I would be even writing this entry!  Lastly this study used a dose of surfactant at 3 mL/kg.  How well would this work with the formulation that we use BLES that requires 5 mL/kg? What were the results? Intervention Failure LMA Group ETT group p Any failure 9 (30%) 23(77%) <0.001 Early failure 1 (3%) 20 (67%) <0.001 Late failure 8 (27%) 3 (10%) 0.181 What do these results tell us?  The majority of failures occurred within an hour of delivery of surfactant in the ETT group?  How does this make any sense?  Gastric aspirates for those in the LMA group but not the INSURE group suggest some surfactant missed the lung in the former so one would think the intubation group should have received more surfactant overall however it would appear to be the premedication.  The rate of needing surfactant afterwards is no different and in fact there is a trend to needing reintubation more often in the LMA group but the study was likely underpowered to detect this difference.  Only two patients were given naloxone to reverse the respiratory depressive effects of morphine in those given the INSURE technique so I can't help but speculate that if this practice was more frequent many of the reintubations might have been avoided.  This group was quite aggressive in sticking to the concept of INSURE as they aimed to extubate following surfactant after 5 - 15 minutes.  I am a strong advocate of providing RSI to those being electively intubated but if the goal is to extubate quickly then I believe one must be ready to administer naloxone soon after extubation if signs of respiratory depression are present and this did not happen effectively in this study.  Some may argue those getting the INSURE technique should not be given any premedication at all but that is a debate that will go on for years I am sure but they may have a valid point given this data. Importantly complications following either procedure were minimal and no different in either group. Where do we go from here? Despite some of the points above I think this study could prove to be important for several reasons.  I think it demonstrates that in larger preterm infants it is possible to avoid any mechanical ventilation and still administer surfactant.  Many studies using the minimally invasive surfactant treatment (MIST) approach have been done but these still require the skill of laryngoscopy which takes a fair bit of skill to master.  The LMA on the other hand is quite easy to place and is a skill that can be taught widely.  Secondly, we know that even a brief period of over distension from PPV can be harmful to the lung therefore a strategy which avoids intubation and direct pressure to the lung may offer some longer term benefit although again this was not the study to demonstrate that. Lastly, I see this as a strategy to look at in more rural locations where access to highly skilled level III care may not be readily available.  We routinely field calls from rural sites with preterm infants born with RDS and the health care provider either is unable to intubate or is reluctant to try in favour of using high flow oxygen via mask.  Many do not have CPAP either to support such infants so by the time our Neonatal Transport team arrives the RDS is quite significant.  Why not try surfactant through the LMA?  If it is poorly seated over the airway and the dose goes into the stomach I don't see them being in any worse shape than if they waited for the team to arrive.  If some or all of the dose gets in though there could be real benefit. Might this be right for your centre?  As we think about outreach education and NRP I think this may well become a strong reason to spend a little more time on LMA training.  We may be on to something!  

AllThingsNeonatal

AllThingsNeonatal

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