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AllThingsNeonatal

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About AllThingsNeonatal

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    Michael
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    Narvey
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  1. 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…
  2. Hypoglycemia has to be one of the most common conditions that we screen for or treat in the NICU and moreover in newborn care in general. The Canadian Pediatric Society identifies small for gestational age infants (weight <10th percentile), large for gestational age (LGA; weight > 90th percentile) infants, infants of diabetic mothers (IDMs) and preterm infants as being high risk for hypoglycemia. It is advised then to screen such babies in the absence of symptoms for hypoglycemia 2 hours after birth after a feed has been provided (whether by breast or bottle). I am sure though if you ask just about any practitioner out there, they will tell you a story about a baby with “no risk factors” who had hypoglycemia. These one-off cases have the effect though of making us want to test everyone for fear that we will miss one. If that is the case though should we be recommending that all babies get at least one check? The Canadian Pediatric Surveillance Program (CPSP) The CPSP is a branch of the Canadian Pediatric Society that “provides an innovative means to undertake active paediatric surveillance and increase awareness of childhood disorders that are high in disability, morbidity, mortality and economic cost to society, despite their low frequency. I submit my surveys each month as i hope other Canadian Pediatricians do and help to determine the impact of these rare conditions in our Canadian population. Like with any survey we rely on people taking the time to submit but there is always the risk that what is being sent in under represents the true burden of illness as some cases may not be identified. Having said that, it is the best we have! Turning our attention to hypoglycemia in low risk newborns From April 2014 to March 2016 the CPSP searched for these types of patients and just published the results of their findings in Hypoglycemia in unmonitored full-term newborns—a surveillance study by Flavin MP et al. What I like about the study is that they have been able to look at a group of babies that fall outside those identified as being at risk in the CPS statement Screening guidelines for newborns at risk for low blood glucose. They were looking for severe hypoglycemia by using a threshold of < 2.0 mmol/L (36 mg/dl) and all infants must have received IV dextrose. In the end after excluding ineligible cases they had 93 babies who met criteria. Based on the Canadian birth rate this translates to an incidence of 1 in every 8378 births. These babies were all supposed to be low risk but there were in fact clues that while not strictly identified as risks in the CPS statement could have increased the likelihood of a low blood glucose. Twenty three percent of mothers had maternal hypertension and another 23% were obese while 47% had excessive weight gain during pregnancy. Furthermore, 8% of mothers were treated with a beta blocker (most likely labetalol I would think) during pregnancy which is a risk factor for hypoglycemia although not specifically cited in the current CPS statement. A concerning finding as well was the likelihood of severe symptoms in this group on presentation. Twenty percent presented with major clinical signs (seizure, apnea or cyanosis). Median glucose levels at presentation were much lower than those without major signs (median = 0.8 mmol/L, interquartile range [IQR] = 0.5 versus 1.6 mmol/L, IQR = 0.7; P < 0.001). Lastly, providers were asked about neurodevelopmental concerns at discharge approximately 20% were thought to have issues. Are these patients really low risk though? Twenty five percent of the patients submitted had a birth weight less than the 10%ile for GA. These patients as per the CPS guideline recommendations are actually considered at risk and should have been screened. The second issue to address has to do with the way we diagnose diabetes in pregnancy. All women are provided with the oral glucose tolerance test around 28 weeks of pregnancy. No test is perfect but it is the best we have. Women who have excessive weight gain in pregnancy (almost 50% of the cohort) are at higher risk of developing diabetes or some degree of insulin resistance as are those who are classified as obese. I have long suspected and think it may be the case here that some babies who do not meet the criteria for screening as their mothers do not have a diagnosis of GDM actually are at risk due to some degree of insulin resistance or perhaps their mothers develop GDM later. The evidence for this are the occasional LGA babies who are born to mothers without a GDM diagnosis but who clearly have been exposed to high insulin levels as they behave like such affected infants with poor feeding and low sugars in the newborn period. The authors here comment on those that were SGA but how many in this cohort were LGA? The effect of hypertension can also not be minimized which was present in about a quarter of patients. These babies while not being officially SGA may have experienced a deceleration in weight gain in the last few weeks but remained above the 10%ile. These infants would not have the glycogen stores to transition successfully but would not be targeted as being at risk by the current definitions. Should we be screening everyone then? If we acknowledge that about 25% were IUGR in this study (<10%ile) and should have been screened, the expected rate would be 1:1170 births alone. In Manitoba with our 17000 births a year we would capture about two extra babies a year which translates into a low of pokes for a lot of healthy babies. Given the further information that 1:5 babies who are identified may have neurodevelopmental concerns it would take about 2-3 years of testing to prevent one concern. That pick up rate for me is far too low to subject so many babies to testing. What this study though does highlight is the need to view risk factors a little less strictly. Babies who are almost meeting the criteria for being LGA or those whose mother’s have taken lebetalol should have a low threshold for screening. Should hypertension on medications, excessive maternal weight gain or obesity in the mother be considered a risk? What I didn’t see in the end of this study were patients who truly were AGA, being born to healthy non overweight mothers presenting as high risk. Maybe what is really needed based on this study is to re-evaluate what we consider at risk. In the meantime, maybe we should be testing a few extra babies who fall into these “lesser” risk categories. Better yet a study isolating such patients and looking at the frequency of hypoglycemia in these patients is warranted to get a better idea of whether they are indeed risks.
  3. Skin to skin care or kangaroo care is all the rage and I am the first one to offer my support for it. Questions persist though as to whether from a physiological standpoint, babies are more stable in an isolette in a quiet environment or out in the open on their mother or father’s chests. Bornhorst et al expressed caution in their study Skin-to-skin (kangaroo) care, respiratory control, and thermoregulation. In a surprising finding, babies with an average gestational age of 29 weeks were monitored for a number of physiological parameters and found to have more frequent apnea and higher heart rates than when in an isolette. The study was small though and while there were statistical differences in these parameters they may not have had much clinical significance (1.5 to 2.8 per hour for apnea, bradycardia or desaturation events). Furthermore, does an increase in such events translate into any changes in cerebral oxygenation that might in turn have implications for later development? Tough to say based on a study of this magnitude but it certainly does raise some eyebrows. What if we could look at cerebral oxygenation? As you might have guessed, that is exactly what has been done by Lorenz L et al in their recent paper Cerebral oxygenation during skin-to-skin care in preterm infants not receiving respiratory support.The goal of this study was to look at 40 preterm infants without any respiratory distress and determine whether cerebral oxygenation (rStO2)was better in their isolette or in skin to skin care (SSC). They allowed each infant to serve as their own control by have three 90 minute periods each including the first thirty minutes as a washout period. Each infant started their monitoring in the isolette then went to SSC then back to the isolette. The primary outcome the power calculation was based on was the difference in rStO2 between SSC and in the isolette. Secondary measures looked at such outcomes as HR, O2 sat, active and quiet sleep percentages, bradycardic events as lastly periods of cerebral hypoxia or hyperoxia. Normal cerebral oxygenation was defined as being between 55 to 85%. Surprising results? Perhaps its the start of a trend but again the results were a bit surprising showing a better rStO2 when in the isolette (−1.3 (−2.2 to −0.4)%, p<0.01). Other results are summarized in the table below: Mean difference in outcomes Variable SSC Isolette Difference in mean p rStO2 73.6 74.8 -1.3 <0.01 SpO2 (median) 97 97 -1.1 0.02 HR 161 156 5 <0.01 % time in quiet sleep 58.6 34.6 24 <0.01 No differences were seen in bradycardic events, apnea, cerebral hypoexmia or hyperoxemia. The authors found that SSC periods in fact failed the “non-inferiority” testing indicating that from a rStO2 standpoint, babies were more stable when not doing SSC! Taking a closer look though one could argue that even if this is true does it really matter? What is the impact on a growing preterm infant if their cerebral oxygenation is 1.3 percentage points on average lower during SSC or if their HR is 5 beats per minute faster? I can’t help but think that this is an example of statistical significance without clinical significance. Nonetheless, if there isn’t a superiority of these parameters it does leave one asking “should we keep at it?” Benefits of skin to skin care Important outcomes such as reductions in mortality and improved breastfeeding rates cannot be ignored or the positive effects on family bonding that ensue. Some will argue though that the impacts on mortality certainly may be relevant in developing countries where resources are scarce but would we see the same benefits in developed nations. The authors did find a difference though in this study that I think benefits developing preterm infants across the board no matter which country you are in. That benefit is that of Quiet Sleep (QS). As preterm infants develop they tend to spend more time in QS compared to active sleep (AS). From Doussard- Roossevelt J, “Quiet sleep consists of periods of quiescence with regular respiration and heart rate, and synchronous EEG patterns. Active sleep consists of periods of movement with irregular respiration and heart rate, and desynchronous EEG patterns.” In the above table one sees that the percentage of time in QS was significantly increased compared to AS when in SSC. This is important as neurodevelopment is thought to advance during periods of QS as preterm infants age. There may be little difference favouring less oxygen extraction during isolette times but maybe that isn’t such a good thing? Could it be that the small statistical difference in oxygen extraction is because the brain is more active in laying down tracks and making connections? Totally speculative on my part but all that extra quiet sleep has got to be good for something. To answer the question of this post in the title I think the answer is a resounding yes for the more stable infant. What we don’t know at the moment except from anecdotal reports of babies doing better in SSC when really sick is whether on average critically ill babies will be better off in SSC. I suspect the answer is that some will and some won’t. While we like to keep things simple and have a one size fits all answer for most of our questions in the NICU, this one may not be so simple. For now I think we keep promoting SSC for even our sick patients but need to be honest with ourselves and when a patient just isn’t ready for the handling admit it and try again when more stable. For the more stable patient though I think giving more time for neurons to find other neurons and make new connections is a good thing to pursue!
  4. Caffeine seems to be good for preterm infants. We know that it reduces the frequency of apnea in the this population and moreover facilitates weaning off the ventilator in a shorter time frame than if one never received it at all. The earlier you give it also seems to make a difference as shown in the Cochrane review on prophylactic caffeine. When given in such a fashion the chances of successful extubation increase. Less time on the ventilator not surprisingly leads to less chronic lung disease which is also a good thing. I have written about caffeine more than once though so why is this post different? The question now seems to be how much caffeine is enough to get the best outcomes for our infants. Last month I wrote about the fact that as the half life of caffeine in the growing preterm infant shortens, our strategy in the NICU might be to change the dosing of caffeine as the patient ages. Some time ago though I wrote about the use of higher doses of caffeine and in the study analyzed warned that there had been a finding of increased cerebellar hemorrhage in the group randomized to receive the higher dosing. I don’t know about where you work but we are starting to see a trend towards using higher caffeine base dosing above 5 mg/kg/d. Essentially, we are at times “titrating to effect” with dosing being as high as 8-10 mg/kg/d of caffeine base. Does it work to improve meaningful outcomes? This month Vliegenthart R et al published a systematic review of all RCTs that compared a high vs low dosing strategy for caffeine in infants under 32 weeks at birth; High versus standard dose caffeine for apnoea: a systematic review. All told there were 6 studies that met the criteria for inclusion. Low dosing (all in caffeine base) was considered to be 5- 15 mg/kg with a maintenance dose of 2.5 mg/kg to 5 mg/kg. High dosing was a load of 5 mg/kg to 40 mg/kg with a maintenance of 2.5 mg/kg to 15 mg/kg. The variability in the dosing (some of which I would not consider high at all) makes the quality of the included studies questionable so a word of warning that the results may not truly be “high” vs “low” but rather “inconsistently high” vs. “inconsistently low”. The results though may show some interesting findings that I think provide some reassurance that higher dosing can allow us to sleep at night. On the positive front, while there was no benefit to BPD and mortality at 36 weeks PMA they did find if they looked only at those babies who were treated with caffeine greater than 14 days there was a statistically significant difference in both reduction of BPD and decreased risk of BPD and mortality. This makes quite a bit of sense if you think about it for a moment. If we know that caffeine improves the chances of successful extubation and we also know it reduces apnea, then who might be on caffeine for less than 2 weeks? The most stable of babies I would expect! These babies were all < 32 weeks at birth. What the review suggests is that those babies who needed caffeine for longer durations benefit the most from the higher dose. I think I can buy that. On the adverse event side, I suppose it shouldn’t surprise many that the risk of tachycardia was statistically increased with an RR of 3.4. Anyone who has explored higher dosing would certainly buy that as a side effect that we probably didn’t need an RCT to prove to us. Never mind that, have you ever taken your own pulse after a couple strong coffees in the morning? What did it not show? It’s what the study didn’t show that is almost equally interesting. The cerebellar hemorrhages seen in the study I previously wrote about were not seen at all in the other studies. There could be a lesson in there about taking too much stock in secondary outcomes in small studies… Also of note, looking at longer term outcome measures there appears to be no evidence of harm when the patients are all pooled together. The total number of patients in all of these studies was 620 which for a neonatal systematic review is not bad. A larger RCT may be needed to conclusively tell us what to do with a high and low dosing strategy that we can all agree on. What do we do though in the here and now? More specifically, if you are on call tomorrow and a baby is on 5 mg/kg/d of caffeine already, will you intubate them if they are having copious apneic events or give them a higher dose of caffeine when CPAP or NIPPV that they are already on isn’t cutting it? That is where the truth about how you feel about the evidence really comes out. These decisions are never easy but unfortunately you sometimes have to make a decision and the perfect study hasn’t been done yet. I am not sure where you sit on this but I think this study while certainly flawed gives me some comfort that nothing is truly standing out especially given the fact that some of the “high dose” studies were truly high. Will see what happens with my next patient!
  5. Gentle ventilation must start from birth

    thank you for such an insightful comment and refreshing all of our memories regarding Dr. Wung's incredible results
  6. 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.
  7. A common concern in the NICU these days is the lack of opportunity to intubate. A combination of an increasing pool of learners combined with a move towards a greater reliance on non-invasive means of respiratory support is to blame in large part. With this trend comes a declining opportunity to practice this important skill and with it a challenge to get a tube into the trachea when it really counts. One such situation is a baby with escalating FiO2 requirements who one wishes to provide surfactant to. Work continues to be done in the area of aerosolized surfactant but as of yet this is not quite ready for prime time. What if there was another way to get surfactant to where it was needed without having to instill it directly into the trachea whether through a catheter (using minimally invasive techniques) or through an endotracheal tube? Installation of surfactant into the trachea Lamberska T et al have published an interesting pilot study looking at this exact strategy. Their paper entitled Oropharyngeal surfactant can improve initial stabilisation and reduce rescue intubation in infants born below 25 weeks of gestation takes a look at a strategy of instilling 1.5 mL of curosurf directly into the pharynx for infants 22-24 weeks through a catheter inserted 3-4 cm past the lips as a rapid bolus concurrent with a sustained inflation maneuver (SIM) of 25 cm of H2O for 15 seconds. Two more SIMs were allowed of the heart rate remained < 100 after 15 seconds of SIM. The theory here was that the SIM would trigger an aspiration reflex as the pressure in the pharynx increased leading to distribution of surfactant to the lung. The study compared three epochs from January 2011 - December 2012 when SIM was not generally practiced to July 2014 - December 2015 when SIM was obligatory. The actual study group was the period in between when prophylactic surfactant with SIM was practiced for 19 infants. A strength of the study was that resuscitation practices were fairly standard outside of these changes in practice immediately after delivery and the decision to intubate if the FiO2 was persistently above 30% for infants on CPAP. A weakness is the size of the study with only 19 patients receiving this technique being compared to 20 patients before and 20 after that period. Not very big and secondly no blinding was used so when looking at respiratory outcomes one has to be careful to ensure that no bias may have crept in. If the researchers were strongly hoping for an effect might they ignore some of the "rules around intubation" and allow FiO2 to creep a little higher on CPAP as an example? Hard to say but a risk with this type of study. What did they find? The patients in the three epochs were no different from one and other with one potentially important exception. There were higher rates of antenatal steroid use in the study group (95% vs 75 and 80% in the pre and post study epochs). Given the effect of antenatal steroids on reducing respiratory morbidity, this cannot be ignored and written off. Despite this difference it is hard to ignore the difference in endotracheal intubation in the delivery room with only 16% needing this in the study group vs 75 and 55% in the other two time periods. Interestingly, all of the babies intubated in the delivery area received surfactant at the same percentages as above. The need for surfactant in the NICU however was much higher in the study period with 79% receiving a dose in the study group vs 20 and 35% in the pre and post study groups. Other outcomes such as IVH, severe ROP and BPD were looked at with no differences but the sample again was small. What can we take from this? Even taking into account the effect of antenatal steroids, I would surmise that some surfactant did indeed get into the trachea of the infants in the study group. This likely explains the temporary benefit the babies had in the delivery suite. I suspect that there simply was not a big enough dose to fully treat their RDS leading to eventual failure on CPAP and a requirement for intubation. Is all lost though? Not really I think. Imagine you are in a centre where the Neonatologist is not in house and while he/she is called to the delivery they just don't make it in time. The trainee tries to intubate but can't get the tube in. Rather than trying several times and causing significant amounts of airway trauma (as well as trauma to their own self confidence) they could abandon further attempts and try instilling some surfactant into the pharynx and proving a SIM. If it works at all the baby might improve enough to buy some time for them to be stabilized on CPAP allowing time for another intubater to arrive. While I don't think there is enough here to recommend this as an everyday practice there just might be enough to use this when the going gets tough. No doubt a larger study will reveal whether there really is something here to incorporate into the tool chest that we use to save the lives of our smallest infants.
  8. Hypoglycemia has to be one of the most common conditions that we treat in the newborn admitted to NICU. For many infants the transitional phase of hypoglycemia can be longer than a couple low blood sugars and as nurses commonly express, it doesn’t take long before the heels of these infants begin to resemble hamburger. For those of you who have used diazoxide in the treatment of hypoglycemia you know that it works and it works quickly to raise the blood sugar. It works by blocking the production of insulin from the pancreas, so particularly in the setting of an infant with detectable insulin levels while hypoglycemic (should be undetectable with a low blood sugar) it can be quite effective. In my own practice I have found that often within one or two doses of the medication with treatment being 5-15 mg/kg/d it can seem to work miracles. Years ago I heard rumours of a trial from birth of this medication in infants of diabetic mothers but saw nothing come to fruition. As someone though who really strives to critically look at every needle poke and strongly consider the need I have always leaned towards the use of this medication if only to reduce what I suspected would be a large number of heel lances. A Study Comes Forward Balachandran B et al published a paper on this topic this week in Acta Paediatrica entitled Randomised controlled trial of diazoxide for small for gestational age neonates with hyperinsulinaemic hypoglycaemia provided early hypoglycaemic control without adverse effects. To be clear this is a very small study with only 30 patients in total (15 in the diazoxide and 15 in the placebo arms) and as they had nothing to go on for determining a sample size needed there was no power calculation. The authors chose to look at a very specific group of neonates that were SGA and had hypoinsulinemic hypoglycemia so we need to resist extrapolating to other patient groups such as IDMs in case there is a positive effect here. With those warnings though, what they did was devise a stepwise approach to initiating diazoxide at 8 mg/kg/d and escalating the dose to as much as 12 mg/kg/d followed by a standardized wean following blood glucose stability. The primary outcome in this case was the number of hours required to achieve a stable glucose with a glucose infusion rate of =< 4mg/kg/min. They examined a number of secondary outcomes as well including duration of IV fluids, episodes of sepsis and time to achieve full feeds as well as mortality. Given the small sample size though I would resist drawing too many conclusions about these secondary outcomes but they are reported nonetheless. From the paper the Kaplan Meier curve indicates a faster time to stability of blood sugars for 6 hours favouring the diazoxide group. Importantly there were no differences in baseline insulin or cortisol levels between the groups which might explain differing times to glycemic control. Intravenous reductions with feeding increments were also standardized for the study to ensure comparable treatment strategies aside from the provided diazoxide or placebo. Claim of Safety The authors note there were no differences in mortality or number of sepsis episodes between the groups. They did find a statistically significant reduction in duration of IV fluid requirements which is likely believable despite my earlier warning as the length of time to achieve control was significantly reduced. The fact remains though with such few patients I would take claims of safety with a grain of salt. You might think at this point though that I would be a champion for the therapy but despite my earlier enthusiasm I do have some reservations. The median time to achieve glycemic control was 40 vs 72.5 hours with a p value of 0.015 which is certainly significant but really we are talking about nearly 2 vs 3 days of management. Is diazoxide truly safe enough to warrant the 30 hour reduction in time to glycemic control? Assuming q3h point of care glucose checks this would be about 8-10 less pokes as a best case scenario but more likely 4-6 less as near the end of checking glucoses as the patient becomes more stable the number of pokes usually decreases. Is diazoxide worth it though? Back in 2015 the FDA issued a warning that diazoxide can lead to pulmonary hypertension. In truth we have seen it in babies where I practice and as such now routinely have an ECHO done before starting the drug to determine if there is any pulmonary hypertension prior to starting the drug and if there is even a hint it is contraindicated. It isn’t too common a complication as in the FDA bulletin (read here) there have been only 11 cases reported since 1973 but it is a risk nonetheless. Thirty patients sadly isn’t enough to rule out this complication and it is worth nothing that the authors did not look for this outcome so we don’t know if any patients suffered this. Am I saying that one should never use diazoxide? Absolutely not but I am suggesting that if you use it then use it with great caution. Although I am delighted the authors chose to perform this study taking all risks into account and looking at the benefit in terms of time on IV and that needed to gain control of blood sugars I can’t say this should be standard of care.
  9. 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!
  10. This must be one of my favourite topics as I have been following the story of early hydrocortisone to reduce BPD for quite some time. It becomes even more enticing when I have met the authors of the studies previously and can see how passionate they are about the possibilities. The PREMILOC study was covered on my site twice now, with the first post being A Shocking Change in Position. Postnatal steroids for ALL microprems? and the second reviewing the 22 month outcome afterwards /2017/05/07/early-hydrocortisone-short-term-gain-without-long-term-pain/. The intervention here was that within 24 hours of birth babies born between 24-27 weeks gestational age were randomized to receive placebo or hydrocortisone 1 mg/kg/d divided q12h for one week followed by 0.5 mg/kg/d for three days. The primary outcome was rate of survival without BPD at 36 weeks PMA. The finding was a positive one with a 9% reduction in this outcome with the use of this strategy. Following these results were the two year follow-up which reported no evidence of harm but the planned analysis by gestational age groupings of 24-25 and 26-27 weeks was not reported at that time but it has just been released this month. Is there a benefit? Of the original cohort the authors are to be commended here as they were able to follow-up 93% of all infants studied at a mean age of 22 months. The methods of assessing their neurological status have been discussed previously but essentially comprised standardized questionnaires for parents, assessment tools and physical examinations. Let’s start off with what they didn’t find. There was no difference between those who received placebo vs hydrocortisone in the 26-27 week group but where it perhaps matters most there was. The infants born at 24-25 weeks are certainly some of our highest risk infants in the NICU. It is in this group that the use of hydrocortisone translated into a statistically significant reduction in the rate of neurodevelopmental impairment. The Global Neurological Assessement scores demonstrated a significant improvement in the hydrocortisone group with a p value of 0.02. Specifically moderate to severe disability was noted in 18% compared to 2% in the group receiving hydrocortisone.They did not find a difference in the neurological exam but that may reflect the lack of physical abnormalities with cognitive deficit remaining. It could also be explained perhaps by the physical examination not being sensitive enough to capture subtle differences. Why might this be? Adding an anti-inflammatory agent into the early phase of a preemies life might spare the brain from white matter damage. Inflammation is well known to inflict injury upon the developing brain and other organs (think BPD, ROP) so dampening these factors in the first ten days of life could bring about such results via a mechanism such as that. When you look at the original findings of the study though, a couple other factors also pop up that likely contribute to these findings as well. Infants in the hydrocortisone group had a statistical reduction in the rate of BPD and PDA ligations. Both of these outcomes have been independently linked to adverse neurodevelopmental outcome so it stands to reason that reducing each of these outcomes in the most vulnerable infants could have a benefit. In fact when you add everything up, is there much reason not to try this approach? Ten days of hydrocortisone has now been shown to reduce BPD, decrease PDA ligations and importantly in the most vulnerable of our infants improve their developmental outcome. I think with this information at our fingertips it becomes increasingly difficult to ignore this approach. Do I think this will become adopted widely? I suspect there will be those who take the Cochrane approach to this and will ask for more well designed RCTs to be done in order to replicate these results or at least confirm a direction of effect which can then be studied as part of a systematic review. There will be those early adopters though who may well take this on. It will be interesting to see as these centres in turn report their before and after comparisons in the literature what the real world impact of this approach might be. Stay tuned as I am sure this is not the last we will hear on this topic!
  11. 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!
  12. 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!
  13. As time goes by, I find myself gravitating to reviews of Canadian research more and more. We have a lot of great research happening in this country of ours and especially when I see an author or two I know personally I find it compelling to review such papers. Today is one of those days as the lead author for a paper is my colleague Dr. Louis here in Winnipeg. Let me put his mind at ease in case he reads this by saying that what follows is not a skewering of the paper he just published using Canadian Neonatal Network data (CNN). Over the last twenty years that I have had the privilege of working in the field of Neonatology we continue to discuss the same things when it comes to the PDA. Does it really cause problems or is it an association for many outcomes? Does treatment make a difference? If you treat then what should you use (ibuprofen, indomethacin, paracetamol)? When should you treat and if you treat early should it be in the first few days or right after birth using a prophylactic approach (provided within 12 hours of delivery)? It is the prophylactic approach which is the subject of this post! Why treat prophylactically? The TIPP trial reported the results in 2001 of the study whose goal was to determine if prophylactic indomethacin use could improve neurosensory impairment at 18 months by reducing rates of severe IVH. The results of the study are well known and showed that while the rates of severe IVH and PDA ligations were reduced through this approach, there was no actual effect on long term outcome. The use of this approach fell off after that for many years but recently resurfaced as some units in Canada opted to start the practice again as the two benefits seen above appeared to be worth using the approach. The thought from a family centred approach, was that eliminating the stress for families of informing them their tiny preterm infant had a serious intracranial bleed and potentially avoiding a surgical ligation with probably vocal cord impairment afterwards were good enough outcomes to warrant this practice. Having used this approach myself I have to admit one consequence is that indomethacin was so effective at closing the PDA most of the time that over time one begins to assume the PDA is in fact closed and is less likely to go hunting for one when the baby is misbehaving later on in their course. What if it didn’t close though? Are there any predictors that can increase our index of suspicion? Answering the question The CNN provides a large database to look retrospectively to answer such a question. In this article, the authors looked at a period from 2010 to 2015 including all infants < 28 weeks gestational age at birth yielding a very large sample of 7397 infants. Of these 843 or 12% received prophylactic indomethacin and from there a little over half (465) still had a PDA. From there, 367 received treatment with eventually 283 needing only medical, 11 having a PDA ligation and 73 having both medical and surgical closure. From this analysis so far I can tell you that providing prophylactic indomethacin certainly does not guarantee closure! When a myriad of risk factors were put into logistic regression a number of interesting risk factors arose accounting for more of less risk of a PDA that needed surgical ligation despite prophylactic treatment. Much like all infants in the NICU, the risk for a persistent PDA was highest with declining GA. The combination of outborn status and short interval of ruptured membranes predicted higher risk. No doubt this is reflective of less frequent antenatal steroid use and even if provided time for it to work. Looking at medical or surgical treatment, surfactant therapy increased risk which may be explained by an improvement in oxygenation contributing to increased left to right shunting as PVR drops. Maternal hypertension and longer duration of rupture of membranes again play a role in reducing risk likely through the mechanism of the former increasing endogenous steroid production and the latter again allowing for steroids to be provided. What can we learn from this paper? I suppose the biggest benefit here is the realization that even with prophylactic indomethacin we are not assured of closure. In particular if there is a lack of antenatal steroid use or a stressed fetus one should be vigilant for the PDA. Interestingly, all of the risks seem to point towards antenatal steroid use. The bottom line then is that this reinforces what is already known and should be the focus of improvement strategies for centres. Increase the rate of antenatal steroid use and you will reduce the risk of a PDA even in the baby receives prophylactic indomethacin. I am happy to report that our centre has taken one step towards this goal by reinforcing to our Obstetrical colleagues that when they receive a call from a referring centre and have a woman who might be in labour it is better to err on the side of caution and just give the steroid course. If they are wrong on arrival then one can always repeat a course later on as we do although repeated courses of steroids are in and of themselves a contentious issue. What can your centre do to improve your results when it comes to antenatal steroid coverage?
  14. We sure do poke a lot of babies to test their blood glucose levels. Some of these babies don’t have so much blood to spare either so checking sugars multiple times a day can drain the body of that precious blood they so need for other functions. Taking too much can always be addressed with a blood transfusion but that as I see it may be avoidable so shouldn’t we do what we can to cut down on blood work? Those with diabetes will be familiar with a continuous glucose monitor (CGM) which is implanted in the skin and can stay in place up to 7 days. The device does require calibration twice a day with a capillary sample to verify it is reading well but this saves a couple pokes a day for those who check four times a day. Such a device could be useful in the NICU where those with hypoglycemia may be checked 6 or more times per day if they are either hypo or hyperglycemic. Cutting this down to two a day would certainly we something worth striving for and if not for the reduction in blood loss then for the minimization of painful procedures. Does it work in small babies? A natural question for sure.Uettweller et al published Real-time continuous glucose monitoring reduces the duration of hypoglycemia episodes: a randomized trial in very low birth weight neonates. In babies with a BW < 1500g they were able to demonstrate in 43 babies (21 with traditional intermittent glucose checks vs 22 with CGM) a reduction in duration of hypoglycemia episodes per patient (CGM 44[10-140] min versus IGM 95[15-520] min, p<0.05). Moreover in this brief study of the first three days of life they also found a reduction in the total number of pokes per patient of 5 pokes (22 vs 16). The numbers however are small and the duration short in only being three days so it did not provide a perfect answer as to whether this technology would work in babies from 500-750g reliably but certainly for older babies, continuous knowledge of the blood glucose in theory would allow for faster response to low sugars and as a result as evidenced by the results led to a decrease in time with a low blood glucose. Improving on these results Galderisi et al just published Continuous Glucose Monitoring in Very Preterm Infants: A Randomized Controlled Trial. The study remains small at 50 and the target group ranging from 28-31 weeks (all < 1500g) but the study followed babies for a longer time frame of 7 days. This study employed an algorithm for adjustments in glucose infusion that required staff to first put data into an excel spreadsheet and then the predictive algorithm dictated whether to increase or decrease the rate of dextrose infusion. In one arm, CGM results were unblinded and the practitioners relied on the rate of change to determine the predicted glucose 15 minutes into the future while in the blinded group the CGM was used but results were not available (retrospectively yes) so changes were made based on the usual practice of obtaining point of care results and modifying glucose infusion rates based on that result. The primary outcome of interest here was percentage of time in the euglycemic range of 72 – 144 mg/dL (4-8 mmol/L). Secondary outcomes were time spent hypo or hyperglycemic (mild hypoglycemia (M-HYPO) (47–71 mg/dL); severe hypoglycemia (S-HYPO) (<47 mg/dL); mild hyperglycemia (M-HYPER) (145–180 mg/dL); and severe hyperglycemia (S-HYPER) (>180 mg/dL)). The study lasted a total of seven days allowing the use of one subcutaneous probe per patient as they can last one week after insertion. How did the approaches compare? As you might have expected, having a predictive model proved superior. Overall after adjusting for sex, gestational age and weight mean time in target using the unblinded CGM was 83% [95% CI, 79%–87%] and of 71% [95% CI, 67%–76%] in B-CGM [P < .001]). As for secondary outcomes one can see that the time spent in the hypo/hyper areas was much less as a percentage of time than using traditional methods of intermittent sampling. One interesting outcome was that the total number of samples used over the study was an average of 2.4 tests per day in the unblinded group vs 2.59 per day in the intermittent sampling group which although statistically different does not seem to have much clinical impact. A few questions remain The idea of using an implanted CGM for infants in the NICU is one that excites me. The lack of a reduction in pokes in a meaningful way is disappointing but I can’t help but wonder if the effect was different whether you were in the first or second half of the week. What if glycemic control in these 29-31 week infants had stabilized by 2-3 days such that you only needed one or two glucose checks in the last half of the week per day? The CGM requires calibration twice daily with POC samples so the lack of a difference my be due to those issues. Future, calibration is rumoured to be possible with one sample so that may change. There is no disputing though that the use of the predictive algorithm made a difference in terms of avoidance of hypo/hyperglycemic episodes. A larger study would be needed to look at whether this impacts harm that may be associated with such variability such as IVH or ROP but it certainly is promising. The biggest issue here is that I cannot see people manually inputting glucose readings on the CGM into an excel sheet in everyday practice. For this to become widely adopted, a simplified approach to prediction would be required or even better a feedback loop whereby data from the CGM would relay to the infusion pump and rates adjusted automatically (with manual override available). The use of CGM is coming though and I can’t help but think in the larger babies born to mothers with diabetes there would be a real heal sparing effect with these. Might this be the next study?
  15. Given that today is world prematurity day it seems fitting to talk about prematurity at the absolute extreme of it. It has been some time since as a regional program we came to accept that we would offer resuscitation to preterm infants born as early as 23 weeks gestational age. This is perhaps a little later in the game that other centers but it took time to digest the idea that the rate of intact survival was high enough to warrant a trial of resuscitation. This of course is not a unilateral decision but rather a decision arrived at after consultation with the family and interprofessional team. To be sure it is not an easy one. Other centers have argued that resuscitation should be offered to those infants as young as 22 weeks gestational age and data now exists due to enough centres doing so to provide families with some guidance as to expected survival rates and importantly the likelihood of disability. This topic has been covered previously in /2015/09/25/winnipeg-hospital-about-to-start-resuscitating-infants-at-23-weeks/. Why cover this topic again? Well an article on CNN might have something to do with it. Resuscitating Below 22 weeks This week as I was perusing the news I came across a rather shocking article on CNN. Born before 22 weeks, ‘most premature’ baby is now thriving. The article tells the tale of a baby delivered at 21 weeks and 4 days that now as a three year old is reaching appropriate milestones without any significant impairments. It is a story that is filled with inspiration and so I am not mistaken I am delighted for this child and their family that this outcome has occurred. When the lay press latches onto stories like this there is no doubt a great deal of sensationalism to them and in turn that gathers a lot of attention. This in turn is a great thing for media. A Few Caveats Though With the exception of pregnancies conceived through IVF the best dating we have is only good to about +/- 5 days when an early first trimester ultrasound is performed or the date of the last menstrual period is fairly certain. A baby though who is born at 21 weeks + 4 days may in fact be 22 +3 days or even more depending on when the dating was done (second trimester worse). Let’s not take away though from the outcome being this good even at 22 weeks. That is a pretty perfect outcome for this family but the point is that this baby may in fact be older than 21 weeks. Secondly, there are millions of babies born each year in North America. Some of these infants are born at 22 weeks. How do they fare overall? From the paper by Rysavy et al from 2015 the results are as follows. If you look at the overall rate of survival it is on an average of 5.1%. If you take a look though at those infants in whom resuscitation is provided that number increases to a mean of 23%. Intact survival is 9% overall. The odds aren’t great but they are there and I suspect the infant in the article is one of those babies. Flipping the argument though to the glass is half empty, 91% of infants born at 22 weeks by best estimate who are offered resuscitation will have a moderate or severe disability if they survive. I am not saying what one should do in this situation but depending on how a family processes the data they will either see the 110 chance of intact survival as a good thing or a 9/10 chance of death or disability as a very bad thing. What a family chooses though is anyone’s best guess. Should we resuscitate below 22 weeks if the family wishes? I guess in the end this really depends on a couple things. First off, how certain are the dates? If there is any degree of uncertainty then perhaps the answer is yes. If the dates are firm then I at least believe there is a barrier at which futility is reached. Perhaps this isn’t at 21 weeks as some patients may indeed be older but think about what you would offer if a family presented at 20 weeks and wanted everything done. What if it were 19 weeks? I suspect the point of futility for all lies somewhere between 19-21 weeks. As I prepare to attend the annual meeting in Ottawa tomorrow for the Fetus and Newborn Committee I think it is prudent to point out just how difficult all of this is. The current statement on Counselling and management for anticipated extremely preterm birth I think hits on many of these issues. The statement is the product on not only the think tank that exists on this committee but was the product of a national consultation. I know I may be biased since I sit on the committee but I do believe it really hits the mark. Should we be thinking about resuscitating at 21 weeks? For me the answer is one clouded by a whole host of variables and not one that can be easily answered here. What I do think though is that the answer in the future may be a yes provided such infants can be put onto an artificial placenta. Even getting a few more weeks of growth before aerating those lungs is necessary may make all the difference. The NICUs of tomorrow certainly may look quite different than they do now.
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