I received this question from a speech-language pathologist who read my blog posts on working in the Neonatal Intensive Care Unit (NICU), and I answer it here.
Question: What are current recommendations on timing of instrumental evaluation following diagnosis of vocal fold impairment with neonates?
I’ll offer some general guidelines, although SLPs should consider the question in context of each infant’s unique co-morbidities—especially respiratory, airway and neurological—as well as feeding history. Also, we can problem-solve most effectively when knowing the likely—or determined—cause for the vocal cord impairment/vocal cord paralysis (VCP), if it’s the left or right cord, and when the last flexible scope by an otolaryngologist occurred.
So many factors require consideration, so I’ll share my clinical reasoning and hope it provides some guidance as you consider each NICU infant individually.
VCP in a neonate might occur as a secondary condition to lesions in the central nervous system or to vascular malformations. These might include Arnold-Chiari malformation, hypoxia or hemorrhage, or trauma from medical procedures like intubation. The infant may or may not show signs or symptoms, so as NICU clinicians, we should always complete a thorough history on every referral. We often express concern for possible VCP before anyone else on the medical team.
A rigid bronchoscopy in the operating room might follow the flexible scope to provide the specifics SLPs need to complete our clinical differential. Look for unilateral or bilateral paralysis. Bilateral paralysis might occur in the open or nearly closed position.
An otolaryngologist can estimate a likely time frame for return of function. This prognosis and anticipated timeline varies. I usually hear them offer a range of six months to two years. During that time, the infant gets regular exams by the otolaryngologist using flexible endoscopy to look for improvement or resolution of vocal cord paralysis over time. In addition, an infant with bilateral VCP in the nearly closed position typically receives a tracheotomy to establish an airway. If bilateral VCP occurs in the open position, a gastrostomy tube is placed to protect the airway during feeding.
The NICU infant—by nature of his multi-system immaturity—also has increased risk for airway compromise when VCP occurs. The risk increases in those with multiple co-morbidities. My clinical experience suggests that a high percentage of infants with VCP—especially those born before 28 weeks, weighing less than 1000 grams and with chronic lung disease—also experience altered or impaired swallowing physiology.
You’ll frequently see the inability to achieve effective airway closure during the swallow, though there may be co-existing issues—for example, a delay in swallow initiation due to increased work of breathing and the resulting need for an urgent breath. Also, differences in the infant’s swallowing anatomy and physiology cause the epiglottis to not be displaced during swallowing. An NICU infant with VCP has a far greater risk of aspiration than an older infant, child or adult.
Sometimes, NICU teams consult us after initiating oral feeding, and the infant already shows overt decompensation. After reviewing the history and completing a clinical examination, I typically recommend the neonatologist consider an instrumental assessment of swallowing physiology. I recommend this procedure not to see if the infant aspirates—though we might find this happens—but determine to what extent swallowing physiology might be impaired or altered by the VCP in conjunction with other potential co-morbidities.
If NICU staff perceive the infant is ready for oral feeding and they consult us prior to the feeding, we can help support oral-sensory-motor readiness or make recommendations about how to proceed. I prefer the infant receive a small, cautious oral feeding experience with the SLP prior to going to radiology. My clinical preference—understanding the inherent risk—is to give the infant the sensory-motor experience of purposeful swallowing, rather than have his first oral feeding attempt take place in radiology. If the isolated VCP seems to cause altered or impaired swallowing, I typically wouldn’t repeat oral feeding until we better understand his swallowing physiology and see evidence of improved vocal cord function as documented by a repeat flexible scope.
Many neonatologists and NICU nurses have limited understanding of swallowing physiology. So we must repeatedly explain this physiology and advocate for safe feeding.
Do you have questions about NICU practice? E-mail them to me at firstname.lastname@example.org. I’ll select questions to answer for future columns.
Catherine S. Shaker, MS, CCC-SLP, BCS-S, an clinician since 1977, works in acute care/inpatient pediatrics at Florida Hospital for Children in Orlando, Florida. She is an affiliate of ASHA Special Interest Group 13, Swallowing and Swallowing Disorders (Dysphagia). Follow her at www.Shaker4SwallowingandFeeding.com or email email@example.com.