Lack of Pediatric Viral Filters and Suggestions-Covid patients

[elee]

In preparation form potential Covid+ or PUI in the delivery and NICU setting, viral filters are suggested while using self inflated resuscitators, NIV (high flow cannula, NIPPV, bubble CPAP, SiPAP, CPAP), and ventilators.  Pediatric Viral filters are on back order and we have only adult viral filters of various specs depending on manufacturer (min 200 ml VT or > 125 ml VT for others).  The representatives for Drager have stated that many are using their ventilators at the expiratory limb at the exhalation valve which we can do in the Bunnel Jet ventilator.  We are awaiting feedback from Sensormedics for Oscillator.  We are going to like going to a tent set up if patient is on High flow, bCPAP and SiPAP unless can of the distinguished colleagues can help in determining if there is another work around or experience with using adult viral filter for the NIV.  We are planning on placing respiratory supported patient in negative pressure room with full PPE but if there is limitations in space and if overwhelmed will need to place in regular patient room in isolette (single bed rooms unless overwhelmed will cluster.)

The second issue is adaption of neonatal self inflator bags or T-piece resuscitator for adult viral filter and is there any experience adapting this.  

Thanks for any assistance.

Edward Lee, MD

Winchester Medical Center, NICU

Winchester, VA, USA

[Stefan Johansson]

Thanks Edward for posting, I believe this is a common situation. I will share your post in our various channels, lets hope for more useful feedback than mine.

I have not been involved in getting filters to our unit, but I just wanted to share what we use (for the NeoPUFF, Fabian CPAP and Leoni vent's)

 

[Martin.Keszler]

Be careful when using large filters, as this adds very large dead space to the system whey using the T-piece resuscitator (e.g. NeoPuff - see first pic). Exhalation occurs via the opening of the PEEP valve at the top, so the filter is in-line. With mask ventilation, there is probably enough leak around the mask to wash out the dead space, but if used in an intubated baby, you would likely have significant dead space gas rebreathing with hypercapnia. With most self-inflating bags the filter can be placed on the expiratory limb as shown in the second picture, therefore there is no added dead space. Detail shows the fishmouth valve that directs expired gas to the filter and PEEP valve. So, until you can get your hands on neonatal filters, you might be better off using a SIB, despite the other problems. Smaller filters are available and should be OK to use with the T-piece.

[Stefan Johansson]

Another aspect of filtering air... our hospital hygiene was a bit sceptical about our wish to use filters. They argue that the humidity will make the filter less effective, i.e. viruses can still be coming through. Like more simple face mask filters (not the N95's) that are also more for the "look" after a while on, than for stopping viruses. But, we will still use those filters, they won't make things worse at least (unless a large dead space etc, thanks a lot @Martin.Keszler for that input)

[dr nalini]

thanks a lot @ Dr Martin Keszler for nice inputs 

here few more informations from different sources 

1. US Davis -

 

At Stanford 

Neonatal-Respiratory-Filters_EXAMPLE_Stanford-Health-Care_032420.pdf

At LAC -USC 

Thermoflo filter port angle used in neonatal setting , information with image available at  cpqcc covid site.

[dr nalini]

drager pediatrics filter twin star family pediatrics/neonatal can be used with 8 -20 ml of dead space with 99.99 viral particle filtraion efficiency