2017 Sec 1 Green Book

Dahl et al

A 2014 study by Vroegop et al retrospectively examined a case series of 1249 adult patients who underwent both PSG and DISE. 10 This study found a statistically significant association between AHI and airway obstruction at the level of the epiglottis. DeCorso et al prospectively evaluated the relationship between PSG parameters and airway obstruc- tion on DISE in a cohort of 138 adult patients with OSA. 11 This study utilized the VOTE system to grade the anatomic obstruction on DISE, and the authors found a statistically significant association between AHI and the severity of ana- tomic obstruction on DISE. While both these studies found a correlation between anatomic obstruction on DISE and pre-DISE PSG parameters, they included only adult patients; the management of pediatric OSA patients is very different from that of adults, and these results may not be applicable to children. While the above studies represent significant contribu- tions to the DISE literature, data derived from adult OSA patients will not necessarily have a direct correlation with pediatric OSA patients. There are a number of important differences to point out regarding the etiology and manage- ment of pediatric and adult OSA: the obvious physiologic differences (eg, airway size and compliance), the presence of medical comorbidities associated with the aging process, the differences in neuromuscular control, the prevalence of morbid obesity, and the potential for growth and continued development that likely differentiate pediatric from adult OSA. In adults, surgical intervention is considered only after an appropriate trial of continuous positive airway pres- sure (CPAP) treatment. In children, surgery is often the first-line therapy; the clinical expertise necessary to manage CPAP in children is scarce. 12 In addition, CPAP is not Food and Drug Administration approved for outpatient use in patients \ 40 kg, and industry support in terms of providing appropriate equipment for pediatric CPAP is limited. Such differences highlight the need for continued research into pediatric DISE as well as the development of DISE-directed surgical procedures. Given the weak to moderate correlation coefficients obtained from our statistical analysis, there are other factors not con- trolled for in the present study that influenced the relationship between the level of anatomic obstruction observed on DISE and the severity of pediatric OSA in this study. First, the sur- geons performing DISE were not blinded to the preendoscopy PSG parameters; this introduces bias that we were not able to control for using the outlined statistical methods. Given the ret- rospective nature of the present study, it was not feasible to blind the surgeons from the PSG data, as such data were used to determine each patient’s candidacy to undergo DISE and DISE-directed surgery for OSA. However, these correlations still provide the needed foundational data to build further pro- spective investigations performed in a blinded manner similar to the methods described in our initial work. 8 For the present study, we chose to include all children who presented to our institutions with a PSG and met the criteria for undergoing DISE, regardless of age, severity of OSA, and medical com- plexity. This ‘‘real world’’ strategy, when coupled with basic

PSG results, provides a broad illustration of these early correla- tions, again helping to set the stage for further studies that will ideally focus on both typically developing and medically com- plex populations. In addition, the present study included data from DISE performed by 8 attending surgeons and PSGs performed at multiple sleep laboratories; the differences in surgical tech- nique and PSG interpretation introduce variability that cannot be controlled for in our statistical model. There was also no documentation of the anesthetic technique used for the DISE procedures included in this study. The specific doses and durations of the anesthesia administered during DISE or variations from the institutional protocols for DISE anesthesia were not collected as part of the study and there- fore could not be included in our analysis. Moving forward, we propose to use the results from the present study as a basis for a multicenter prospective study evaluating the association between PSG parameters and the level of anatomic obstruction on pediatric DISE. Expanding the breadth and depth of investigations via PSG parameters, surgical and anesthetic techniques, and patient-reported out- comes (including quality of life) and focusing on specific patient populations will further guide research studies that will undoubtedly help to shape the clinical practice of treat- ing the many facets of pediatric OSA. To do so, we will need to follow patients undergoing DISE-directed surgery longi- tudinally and collect data from postintervention PSGs to determine the impact of such procedures on PSG parameters and quality-of-life measures. In addition, with a larger cohort of patients, we will be able to look at specific sites of ana- tomic obstruction, as defined by the C-P score, to character- ize the impact of that site or a procedure directed at that anatomic location in the pathophysiology and treatment of pediatric OSA. Such an approach should also allow us to examine the incidence and treatment of pediatric OSA caused by multiple sites of airway obstruction. Author Contributions John P. Dahl , conception and design, data acquisition, analysis, and interpretation, drafting the work, critical revisions, final approval and accountability for entire product; Craig Miller , data acquisition and interpretation, critical revisions, final approval and accountability for entire product; Patricia L. Purcell , conception and design, data acquisition, analysis, and interpretation, drafting the work, critical revisions, final approval and accountability for entire product; David A. Zopf , data acquisition and interpretation, critical revisions, final approval and accountability for entire prod- uct; Kaalan Johnson , data acquisition and interpretation, critical revisions, final approval and accountability for entire product; David L. Horn , data acquisition and interpretation, critical revi- sions, final approval and accountability for entire product; Maida L. Chen , data acquisition and interpretation, critical revisions, final approval and accountability for entire product; Dylan K. Chan , data acquisition and interpretation, critical revisions, final approval and accountability for entire product; Sanjay R. Parikh , conception and design, data acquisition, analysis, and interpreta- tion, drafting the work, critical revisions, final approval and accountability for entire product.

55