Research Corner: Dysphagia in infants with single ventricle anatomy following stage 1 palliation: Physiologic correlates and response to treatment


Background: Deficits in swallowing physiology are a leading morbidity for infants with functional single ventricles and systemic outflow tract obstruction following stage 1 palliation. Despite the high prevalence of this condition, the underlying deficits that cause this post-operative impairment remain poorly understood.

Objective: Identify the physiologic correlates of dysphagia in infants with functional single ventricles and systemic outflow tract obstruction following stage 1 palliative surgery.

Methods: Postoperative fiberoptic laryngoscopies and videofluoroscopic swallow studies (VFSS) were conducted sequentially on infants with functional single ventricles following stage 1 palliative surgery. Infants were dichotomized as having normal or impaired laryngeal function based on laryngoscopy findings. VFSS were evaluated frame-by-frame using a scale that quantifies performance within 11 components of swallowing physiology. Physiologic attributes within each component were categorized as high functioning or low functioning based on their ability to support milk ingestion without bolus airway entry.

Results: Thirty-six infants (25 male) were included in the investigation. Twenty-four underwent the Norwood procedure and twelve underwent the Hybrid procedure. Low function physiologic patterns were observed within multiple swallowing components during the ingestion of thin barium as characterized by 4 sucks per swallow (36%), initiation of pharyngeal swallow below the level of the valleculae (83%), and incomplete late laryngeal vestibular closure (56%) at the height of the swallow. Swallowing deficits contributed to aspiration in 50% of infants. Although nectar thick liquids reduced the rate of aspiration (P 5 .006), aspiration rates remained high (27%). No differences in rates of penetration or aspiration were observed between infants with normal and impaired laryngeal function.

Conclusions: Deficits in swallowing physiology contribute to penetration and aspiration following stage 1 palliation among infants with normal and impaired laryngeal function. Although thickened liquids may improve airway protection for select infants, they may inhibit their ability to extract the bolus and meet nutritional needs.

McGrattan, K. E., McGhee, H., DeToma, A., Hill, E. G., Zyblewski, S. C., LeftonGreif, M., … & MartinHarris, B. (2017). Dysphagia in infants with single ventricle anatomy following stage 1 palliation: Physiologic correlates and response to treatment. Congenital Heart Disease.


Research Corner: The prevalence and effects of aspiration among neonates with CHD at the time of discharge


Neonates undergoing heart surgery for CHD are at risk for postoperative gastrointestinal complications and aspiration events. There are limited data regarding the prevalence of aspiration after neonatal cardiothoracic surgery; thus, the effects of aspiration events on this patient population are not well understood. This retrospective chart review examined the prevalence and effects of aspiration among neonates who had undergone cardiac surgery at the time of their discharge.

This study examined the prevalence of aspiration among neonates who had undergone cardiac surgery. Demographic data regarding these patients were analysed in order to determine risk factors for postoperative aspiration. Post-discharge feeding routes and therapeutic interventions were extracted to examine the time spent using alternate feeding routes because of aspiration risk or poor caloric intake. Modified barium swallow study results were used to evaluate the effectiveness of the test as a diagnostic tool.

A retrospective study was undertaken of neonates who had undergone heart surgery from July, 2013 to January, 2014. Data describing patient demographics, feeding methods, and follow-up visits were recorded and compared using a χ2 test for goodness of fit and a Kaplan–Meier graph.

The patient population included 62 infants – 36 of whom were male, and 10 who were born with single-ventricle circulation. The median age at surgery was 6 days (interquartile range=4 to 10 days). Modified barium swallow study results showed that 46% of patients (n=29) aspirated or were at risk for aspiration, as indicated by laryngeal penetration. In addition, 48% (n=10) of subjects with a negative barium swallow or no swallow study demonstrated clinical aspiration events. Tube feedings were required by 66% (n=41) of the participants. The median time spent on tube feeds, whether in combination with oral feeds or exclusive use of a nasogastric or gastric tube, was 54 days; 44% (n=27) of patients received tube feedings for more than 120 days. Premature infants were significantly more likely to have aspiration events than infants delivered at full gestational age (OR p=0.002). Infants with single-ventricle circulation spent a longer time on tube feeds (median=95 days) than infants with two-ventricle defects (median=44 days); the type of cardiac defect was independent of prevalence of an aspiration event.

Aspiration is common following neonatal cardiac surgery. The modified barium swallow study is often used to identify aspiration events and to determine an infant’s risk for aspirating. This leads to a high proportion of infants who require tube feedings following neonatal cardiac surgery.

Karsch, E., Irving, S. Y., Aylward, B. S., & Mahle, W. T. (2017). The prevalence and effects of aspiration among neonates at the time of discharge. Cardiology in the Young, 1-7.


Problem-Solving: Feeding on CPAP and HFNC

Question: Does anyone know of any research articles on the risk of feeding infants (term and/or preterm) who are on HFNC? Also I would love other people’s perspective of “turning down” an infant’s oxygen for the purpose of feeding. For example, a baby is on 4L due to acute illness but oxygen is decreased to 2.5L to feed.

Answer: There are a handful of pertinent articles which may be accessible via a search. The one I am attaching is the only study to look at the effect of NCPAP under videofluoroscopy, and it was done by Louisa Ferrara and her NICU colleagues in NY. Their preliminary results were so worrisome that the neonatologists stopped the study.

Unfortunately, often the conclusion regarding the “safety” and the “tolerance” of NICU infants feeding on NCPAP is determined by volume and perhaps lack of overt or symptomatic decompensation. This study will hopefully re-direct thinking about the impact of the need for this level of respiratory support on the ability to safely swallow under such conditions. As you will see, the study determined that “Oral feeding while on NCPAP significantly increases the risk of laryngeal penetration and tracheal aspiration events,” and recommended caution when initiating oral feedings on NCPAP. The conclusions, unfortunately, did not focus on changes in swallowing physiology under NCPAP

My experience in the NICU suggests that, even for those infants who do not frankly penetrate or aspirate under NCPAP in the “moment” in radiology, we are likely to see adverse effects on swallowing physiology. That, for me, is the most compelling takeaway from this study. Bonnie Martin-Harris has taught us that neither aspiration nor penetration is sufficient or necessary for a swallowing impairment – meaning that our focus needs to be on physiology, because impaired physiology and its etiology(ies) create the conditions under which bolus mis-direction can or does occur.

It is not uncommon for neonates to evidence changes in swallowing physiology due to respiratory co-morbidities, even when stable on less support or indeed on unassisted room air. With infants requiring NCPAP or HHFNC, that is why our assessment of risk related to PO feeding or not PO feeding must consider many factors beyond level of respiratory support required.

Regarding your question about reducing respiratory support from baseline during PO attempt, this study gives us some information. However, the time on less support was brief, compared to the typical 25-30-minute PO feeding time. Because the aerobic demands of PO feeding typically exacerbate baseline WOB and RR in neonates, the full impact of such a change is unclear. If the infant is requiring a certain level of support, the reduction in respiratory support may – over the course of a true feeding – result in the need for urgent breaths, leading swallowing and breathing to uncouple. No one has studied this. What looks to some NICU caregivers to be a “solution” will have its own attendant sequelae, as do many things in the NICU, unfortunately.

And so, we remain in the “gray zone” as I like to call it, where there are more questions than answers, which is where most NICU therapists live. We must therefore consider theoretical constructs related to neonatal swallowing, continue to search for the evidence, use critical reflective thinking and dialogue with our neonatal colleagues. I hope this is helpful.


Problem Solving: Swallowing after Supraglottoplasty

Question from Jennifer SLP: I’m curious to know your thoughts and/or procedures for feeding evals post supraglottoplasty? Do you always do an MBS? Only when indicated? How soon after supraglottoplasty do you do an MBSS (if you do one)? What are your treatment plans/outpatient recommendations if they are not safe to PO? Thank you!

It really depends on the infant’s/child’s history and co-morbidities, as of course each has a unique presentation and requires an individualized differential.

In general, when co-morbidities require a supraglottoplasty is recommended, there is typically an associated adverse effect on swallowing physiology being appreciated pre-op. The post-op swallowing physiology, however, is not always improved. It is sometimes more problematic after the supraglottoplasty, which can actually worsen airway protection and further alter physiology.

The related co-morbidities (e.g., prematurity, sensory-motor issues etc.) and altered pre-op system function (GI, respiratory, neuro etc.) will further affect post-op results.

Perhaps work with the ENT/surgeon/attending as to timing of small PO trial with ST to get the infant/child ready for radiology and then objectively determine any adverse effects along the swallow pathway present post-op, or any impairment/alteration that was appreciated pre-op and persists post-op. Sometimes surgeons assume the supraglottoplasty will “fix” swallowing and that may not be the case, in my experience.

Then here is the updated information from Jennifer, SLP:
This has been really helpful. I’ve been working with the ENT, he doesn’t have an idea of when exactly she will be “healed” from her procedure, but we both agree she may need more time. Here is the case in full:

Ex 36 weeker, brought to hospital at 1 week old for stridor. Found to have severe laryngomalacia – obstructive with the arytenoids collapsing in the airway. Made NPO because (Thank you Catherine – I’ve been to your course!) she couldn’t breathe – so she couldn’t eat. Trialed taste trials, but continued to have increased work of breathing and desats were significant. Had a supraglottalplasty on 9/5/16. Trailed taste trials again on 9/8/16 with little to no stridor but multiple swallows (x5) with each bolus and increased congestion with trials. Continued with taste trials for a week. Medical team pushed for a MBSS, they were worried we were being too conservative as a baby post supraglottalplasty may still continue to have noisy feeding. In the MBSS the baby aspirated on thin and nectar consistencies, even using a preemie nipple, 1-suck pacing, sidelying, 1/2 filled nipple. She had really poor swallow function observed in the MBSS – overall weak sluggish movements, multiple swallows, aspiration on primary swallows and residuals. We are continuing to trial tastes with her conservatively – but no progress thus far. She is now term, and the ENT believes she probably had a poor swallow and once they lasered away the tissue covering her airway, her swallow dysfunction was more obvious. She has no other known co-morbidities.

I’m just wondering when we need to make decisions about her long-term plan? Do we give her more time? Also, has anyone worked with a baby like this and have any successful treatment plans? Thank you so much.

My response:
Thanks for more information. Are there other less obvious co-morbidities, as this sounds atypical for a late preterm (36 weeks GA) with an “isolated” laryngomalacia. What was the etiology (or etiologies) for the aspiration? Were the events silent? Was there any other form of bolus mis-direction? We know she otherwise has no known co-morbdities, but is she presenting normally (neuro, postural tone/movement patterns, oral-pharyngeal reflexes, saliva swallows)? I suspect not, based on what you have told us.

I agree with the ENT that the infant probably had swallowing dysfunction pre-op and once they lasered away the tissue covering her airway, I took away “protection for the airway” and her primary swallowing dysfunction “declared itself”. EER/LPR may be playing a part as it is commonly associated with both LM and silent aspiration according to the research. Wonder if ENT saw evidence of EER/LPR when he scoped her? Is she being treated for EER/LPR? Could there be aspiration both from below and above that might be contributing?

Since this presentation is atypical for a late preterm with LM –are they doing a further work up to help elucidate the bigger picture likely affecting the integrity of her swallow? It is perhaps a separate issue from the original need for a supraglottoplasty and that may help to guide prognosis and plan.

Given the nature of the swallowing impairment you describe, and the interventions so thoughtfully trialed in radiology, I suspect this is not going to resolve in the near future. Keep us posted on the results of a further workup as that should help decision-making. Continued pacifier dips and positive oral-sensory-motor input will be important to keep her system primed for return to PO feeding, as co-morbidities and safety permit.

Erika Lee, one of my SLP colleagues from Oklahoma, reminds us that “the purpose of supraglottoplasty is to improve the infant’s breathing; and if that is accomplished, then feeding usually gets better. The supraglottoplasty usually delivers benefits immediately; but then the effects get better over time as the surgery site heals (especially if a laser was used). Surgeons typically assess the entire airway and palpate the interarytenoid space to assure that there is no laryngeal cleft.” The just published manuscript is attached.

I hope this is helpful.

Please click below for the manuscript…

Supraglottoplasty Otolaryngol Head Neck Surg 2011 (818-22)

Problem Solving: Vomiting in three year old NICU graduate

Question: I need help brainstorming possible etiologies for chronic vomiting/regurgitation with a 3 year old.

Medical hx is significant for 36 week prematurity, hypoplastic left heart syndrome now s/p Fontan on 6/16. On 6/18, pt w/new onset left side weakness; imaging found hypoxic injury and watershed infarct. PMH also significant for submucosal cleft palate and GT dependence. Chart review revealed ongoing ST to address feeding issues from infancy, including oral aversion and decreased oral motor development, both now resolved. Parents report pt is interested in PO feeding and will put all textures in his mouth but chews them and pockets rather than swallowing because he is afraid of vomiting. Assessment revealed mild OM weakness but adequate lingual lateralization and chewing skills. Initial PO trials were with preferred foods (smooth puree and water via straw). After very small volumes (less than a teaspoon of each), pt regurgitated the food/liquid which subsequently expelled everything else he had “eaten” via GT up to 2.5 hours earlier. The gag did not happen until after pt had safely swallowed on both trials (separate events with puree and liquid). Parents report that this happens several times a day and that pt also vomits without PO intake (just GT feeds) but that is less common. Pt has had several MBSS which revealed functional pharyngeal skills (oral skills were lacking in one but that was some time ago). The only UGI pt has had was when he was an infant, as part of the work up for GT but they presented contrast via NGT and only viewed stomach and beyond. Therefore, today, I asked for an esophagram to rule out structural or functional issues in the upper GI sections. This test was negative.

These parents are so frustrated and don’t know why their son is vomiting all the time. What I witnessed did not appear to be related to sensory/behavioral (texture aversion) or swallow dysfunction. I was wondering about UES dysfunction or esophageal pouch/diverticulum but the radiologist did not see evidence of those today. Any suggestions??

There may be a variety of GI issues to consider as part of the differential. You don’ t mention if he also received a Nissen at the time in infancy when his G-Tube was placed; if so this may be part of the puzzle, especially considering the vomiting after G-Tube feedings. His diagnosis of HLHS and multiple surgeries, and subsequent post-cardiac surgery GI complications are quite common, as Shaunda suggested. The lower branch of the vagus can wreak havoc with many of our babies and children post-op. Given his history and pre-morbid feeding challenges (oral aversion, oral-motor problems), there may now be an exacerbation of those premorbid challenges. Given that he must have had some kind of post-op event on or prior to 6/18 that resulted in a documented hypoxic injury and watershed infarct, I wonder if there may also be some alterations in pharyngeal and/or upper esophageal function that may be also part of the etiology. What I mean is that even though there is a strong case for GI issues as a part of your differential, there are apparent recent neuro ones too that, along the swallow pathway, may alter both pharyngeal and upper esophageal (especially UES) swallow function. You mentioned he has had several swallow studies but has there been once since the onset of left sided weakness and the watershed infarct and cardiac repair? This would be a great opportunity to objectify both pharyngeal and upper esophageal swallowing physiology with at least the puree and liquid he clinically appeared to swallow well. His complex history and the recent post-op event suggest to me the need for a current instrumental assessment. Because the UGI is a moment in time, and that his is such a complex presentation, a test result such as a “negative UGI” may not tell the whole story. Perhaps during the swallow study, you may also capture an incidental finding related to GI function, and given the focus on dynamic swallowing in the swallow study (versus what they may focus on in an UGI), you may be able to gather needed data about both pharyngeal and upper esophageal function. The combination of his multiple co-morbidities, and their interaction, is likely quite complex, and the data from a swallow study may help inform the entire team’s perspectives.

Problem Solving: Role of therapist in NICU

Question: I am a NICU therapist in a 57 bed level 4 NICU, we have a very difficult time convincing physicians of the benefit and necessity for speech therapy and OT in the NICU. Chronic babies are ordered as well as babies with a diagnosed syndrome or cleft palate etc. However babies with bleeds, long term intubation and kids with PMA of 24-28 weeks that should have a consult are sometimes overlooked. Prior to my position here I worked in home care / private practice for 17 years and saw NICU graduates with a variety of feeding and swallowing difficulties many of which stemmed from their early feeding difficulties. Is there a standard ordering protocol, an algorithm or other evidence based clinical procedural means to share with the clinical committee to convince practitioners of the value of our work and place in the unit any input would be greatly appreciated.

It is always challenging for NICUs and their nurses to see a need for our services when they have “existed” without the benefit of collaborating with rehabilitation therapists regarding feeding readiness and support for optimal feeding outcomes. Lots of dialogue and conversations are needed with NICU staff and leaders to expose them to current research and what value you add. Focusing on those infants most at risk for feeding problems, based on the evidence, is a good place to start. Take a look at these articles on co-morbidities and feeding written by well-respected neonatal researchers. They profile who are the most at risk fragile feeders and therefore guide us as well to those who will benefit from skilled intervention to support the path to PO feeding via oral-sensory-motor readiness. This includes those born at or under 28 weeks GA, at or under BW 1000 grams and with respiratory, airway and GI co-morbidities. Enjoy these articles!

Jadcherla S.R., Peng, J, et al (2012). Impact of personalized feeding program in 100 NICU infants: Pathophysiology-based approach for better outcomes. Journal of Pediatric Gastroenterology & Nutrition 54(1), 62-70.

Jadcherla, S. R., Wang, M., Vijayapal, A. S., & Leuthner, S. R. (2010). Impact of prematurity and co-morbidities on feeding milestones in neonates: a retrospective study. Journal of Perinatology, 30(3), 201-208.

Park, J., Knafl, G., Thoyre, S., & Brandon, D. (2015). Factors Associated With Feeding Progression in Extremely Preterm Infants. Nursing research, 64(3), 159-167.

Also I wrote this manuscript in 2007. In it there is a set of criteria for referrals in the NICU for feeding support. If I were to write it today, I would add to that criteria but it can be a starting point for you to consider and use in conversations. Shaker, C.S. & Woida, A.M. (2007) An evidence-based approach to nipple feeding in a level III NICU: Nurse autonomy, developmental support and teamwork. Neonatal Network, 26:2, 77-83.

Know that creating a role in your NICU is a journey not a destination. It takes many interactions, patient successes and partnering with bedside nurses to make a culture change that embraces the inclusion of therapists when it comes to feeding. And then it needs to be nurtured every day. Be thoughtful, be informed and be a colleague. Share and listen. Build relationships with nurses who become your advocate. Support families in building a relationship with their infant through feeding, and they will sing your praises to the neonatologists!

I hope this is helpful.