Problem-Solving: Fluoro Time for Neonates

Question:

At the hospitals that I work at we have outdated machines that only capture video swallow studies at 6 frames per second. Are the restrictions the same for fluoro time (I think it’s about 2 min recommended fluoro time at 30 frames per second for peds and neos)?

Catherine’s Answer:

The low frame rate will of course limit the objectification of swallowing physiology, unfortunately, and sometimes can lead to the need for increased exposure time. Multiple citations by Heather Bonilha Shaw would be helpful as you advocate, along with your radiologists, for equipment that provides 30 fps.  Given your situation, ALARA (as low as reasonably achievable) should remain your guide. That said, as I teach across the US and survey attends at my swallow study seminars, is most typical that with neonates, the aim is the least amount necessary but less than 2 minutes; with pediatric patients, less than 5 minutes. Of course, co-morbidities, compliance, previous exposure to x-ray/radiation, and clinical impressions about physiology as your go along in the study, all must be considered.

Our tech tracks the exposure time as we go along, the rad and I are very aware, and at each juncture I am asking myself “have I objectified physiology sufficiently? Do I need more time?” and if so I am very thoughtful about continuing or not. if I need a few more swallows to better elucidate physiology or complete a differential, or to objectify the likely positive impact of an intervention, I usually discuss it with the rad and we agree on further time based on a determined required need. Most infant studies are less than 2 minutes exposure and most of our pediatric patients less than 3 minutes, at 30 fps.

At the end of each study, I think always ask myself, ” is there anything I could have done differently to reduce exposure time?” Maybe not but it keeps my always trying to do better for my little patients. Heather is on the ASHA list serve, and, I am sure, can add her always appreciated thoughts. Her recent commentary (see list serve archives) on a paper suggesting 15 fps in pediatrics so eloquently explained issues even in 15 fps for our population that may also be useful in helping to make the case for equipment that provides 30 fps.

Problem-Solving: Respiratory rates in neonates

Question:
Hot topic and in need of evidence based research regarding bottle feeding the premature infant (or term infant) with tachypnea.

What is everyone’s practice?  No PO feeding if respiratory rate above 60? 70?  Would appreciate research articles and your hospitals guidelines!

Catherine’s answer:

To my knowledge, there is no research to guide practice but rather the it is often neonatologist training,  preference and the extent to which intake is a key driver in a particular NICU. Neina Ferguson published an informative paper in 2015 about preterm infants in  the NICU that correlated tachypnea during PO with subsequent aspiration in radiology.

Ferguson, N. F., Estis, J., Evans, K., Dagenais, P. A., & VanHangehan, J. (2015). A retrospective examination of prandial aspiration in preterm infants. Perspectives on Swallowing and Swallowing Disorders (Dysphagia), 24(4), 162-174.

The paper did not look at impact on physiology in detail, but I clinically see in the NICU population that tachypnea can alter physiology without witnessed aspiration or penetration under fluoroscopy, and thereby create risk for airway invasion.

Some neos write orders to PO if infant is “comfortably tachypneic”, RR under 70.  “Comfortably tachypneic” is a almost parodical , in that tachypnea is rarely co-occurring with a comfortable looking infant, rather infants who are tachypneic may often be  exhibiting other signs of physiologic stress (e.g., nasal flaring/blanching, suprasternal and/or supraclavicular retractions, chin tugging). Increasing RR leads to more shallow insufficient respirations. The need to breathe often and rapidly will create challenges in the swallow-breathe interface, and cause breathing and swallowing to uncouple. It takes a second to complete the pharyngeal swallow, so then a RR over 60 clearly increases risk for airway invasion.

Respiratory Rate, my RT mentors tell me, doesn’t exist in isolation but is rather a part of a bigger picture. Much like, they say, level of respiratory support required does not exist in isolation. It’s each infant’s bigger picture that guides us.

As we advocate and make determinations of relative risk with PO feeding for our preterm infants, we really must look at each infant in the setting of his unique history and co-morbidities and their unique attendant sequelae. An infant post HIE just weaned or HHFNC will require a different algorithm than the former 24 weeker with CLD, contrasted with the term infant who is s/p TEF/EA repair. And, as Dr Coyle says, that is ok. One algorithm won’t work for every patient and it shouldn’t. All of my examples are infant who often have risks for airway invasion but the nuances of each infant will likely yield a slightly different profile from which to problem-solve, with the team.

That is the challenge of our work in the NICU. To look at each infant as a unique patient, and,  in the setting of what we know about him, and what we see clinically, make a well-thought out educated plan to minimize risk, articulate those risks as best we can to the team, establish interventions that optimize safety and assess their impact on an ongoing basis.

In the NICU , we are required to  live in the grey zone…no easy questions and there are no easy answers, more questions than answers, constantly thinking and re-thinking.  Just keep “listening” to each infant Tara, like you are doing, and especially partner with RTs and a neonatologist that respects the complexity of feeding and swallowing so they can think along with you.

Problem-Solving: Vocal Cord Paralysis and Sidelying

Question:

Does anyone know of any research articles regarding the effectiveness of putting an infant with a left vocal fold paralysis in a sidelying position for bottle feeds? Also, what are your thoughts about performing an MBS or FEES prior to initiation of PO feeds?

Answer:

To my knowledge there are no randomized controlled trials or research studies regarding this intervention. The pediatric ENTs who took me under their wing early on in my career suggested it and theoretically it made sense to me. While its proposed purpose (i.ie, placing infant with a left vocal cord paralysis R side down for PO feeing) is to utilize gravity to assist by passively bringing the paralyzed cord to midline, it is unlikely that can simulate true effective closure as one would observe in the setting of normal vocal cord motility.

In addition, if there are other co-occurring co-morbidities that adversely affect airway, postural or swallowing function, those most also be considered in the differential. However, combined with other interventions such as controlling flow rate, co-regulated pacing and resting, we have consistently seen improved dynamic swallowing objectified under fluoroscopy in radiology. That clinical wisdom is a level of evidence base that has helped to guide my practice.

There is also a high risk for a paralyzed R vocal cord post ECMO, so many of our cardiac infants and select preterms who require ECMO. Similarly, I have both clinically and instrumentally observed a left side down position in the setting of a R vocal cord paralysis to be a useful intervention to trial.

Once again, need to consider all co-morbidities that maybe relevant to guide us. I prefer that infants not have their first PO feeding experience in radiology. It doesn’t allow me to complete a cautious limited clinical examination of PO feeding prior to the instrumental, during which time I can begin to formulate a differential regarding the full picture (i.e., potential effects of respiration, state, and other co-morbidities on the infant’s feeding/swallowing function in the context of the infant’s history. Also, during that first feeding, when sensory-motor maps are being established and recruited, they must be on the x-ray table or in an infant seat. That said, we recognize that high risk for airway invasion in the setting of both L and/or R vocal cord motility issues. If clinically indicated, I prefer at least 1-2 very small brief PO feeding experiences with me while I trial the interventions and allow the infant to experience sensory-motor learning under optimal conditions. This can be as little as 5 mls. Because we recognize that swallowing physiology needs to be objectified to guide management for such an infant, an instrumental assessment would then follow. FEES would clearly inform our differential, and a VFSS would provide insight into the dynamic swallow pathway. I hope this is helpful.