QUESTION: I have a 33wker with a VSD that nursing is PO feeding every feeding. Are there studies regarding respiratory rate while feeding? The infant looked comfortable at 65 and below but I told nursing to stop feeding with rate above 80 (or allow major rest break for her to slow it down because she’s often cueing).  I’d love hard data to support those numbers

ANSWER:

I don’t know of any randomized controlled trials that yielded this data. Clinically we know that spontaneous RR is typically different than monitored RR, due to an artifact created by the monitor not consistently sensing rapid shallow breaths. We gather he best data by counting the spontaneous breaths, as it’s more reliable. Anytime the RR is above 60 we know there is greater risk, as it takes a second to complete the pharyngeal swallow. RR over 60 increases risk that the swallow and breathing will co-occur or “collide” as I like to say to parents. Work of breathing often goes hand in hand with the RR but can often be a more worrisome indicator of risk for airway invasion. As the effort goes up, breaths are more shallow, there is then less tidal volume, and the infant is more likely to need an urgent breath. In those moments, the need to breathe will override the swallow. Often this means opening the airway too early or not fully closing it at the moment of the swallow. Because NICU infants are at higher risk to silently aspirate, the infant described may show no outward signs. We know he is a 33 weeker – which means to me that he was born at 33 weeks. What is his PMA? Or are you meaning he is now 33 weeks PMA; if so, what was his GA? Helps me make sense of his risk. The VSD will drive up WOB and RR at baseline, and with the aerobic demands of feeding. Does he have an otherwise unremarkable history except for VSD? Currently requiring respiratory support? What are saturations like with PO? What physiologic and behavioral stress signs do you see even with interventions? What interventions are the nurses using to protect him? Perhaps having you offer guided participation while a nurse feeds and you think along with her, might build a conversation about airway protection and neuroprotection, both of which are likely at risk given what we know.