Laryngomalacia is the most frequent cause of congenital stridor, warranting surgical intervention in up to approximately 10% of children with the condition. In these instances, endoscopic supraglottoplasty is the surgical approach of choice, with good outcomes expected in most cases. Case series demonstrate little difference in outcomes or complications among the different endoscopic instruments used for supraglottoplasty. However, children with associated congenital anomalies, such as concomitant neurologic disease,4,15 cardiac disease,13 and severe gastroesophageal reflux,10,14 have been reported to be at increased risk of surgical failure, requiring higher rates of revision surgery, tracheotomy, or feeding tube insertion. The exact mechanisms for why these children seem to be at increased risk after surgery are unknown but are likely attributable to multifactorial reasons. Complex hypotonia, increased work of breathing, distorted central cardiopulmonary function, and laryngeal edema are all likely to contribute to varying degrees in individual patients. Day et al,11 in a multivariate analysis of 74 patients, reported that the only variable that contributed to supraglottoplasty surgical failure was a history of prematurity, suggesting that failure previously attributed to associated congenital anomalies may be explained by a higher rate of prematurity in these complex comorbidity cases. Along the same lines, Hoff et al13 found that infants requiring supraglottoplasty in their first 2 months of life incurred a significantly higher rate of surgical failure and revision surgery. For the purposes of categorizing patients and analyzing outcome in this review, we defined significant comorbidities as cases involving congenital cardiac disease, neurologic compromise, or severe gastrointestinal reflux. None of the studies had objective measures of cardiac or neurologic compromise degree or of reflux severity defined in their data but simply reported the number of patients in each of these categories. In general, these categories of comorbidities were grouped by the reports to evaluate whether they affected surgical outcome. Only 3 studies11,13,14 had sufficient data to determine outcome by each individual comorbidity separately; therefore, for the purposes of our analysis, all 3 comorbidities were grouped together.