Effect of physical stress on drug-induced sleep endoscopy for obstructive sleep apnea

Drug-induced sleep endoscopy (DISE) is a reliable upper airway evaluation tool, widely used to improve surgical results in patients with obstructive sleep apnea (OSA). Several factors, including sleeping position and depth of sedation, affect DISE findings. This study aimed to evaluate the impact of physical stress on DISE findings. Eighty-five patients with OSA underwent two DISE examinations at the same level of sedation. The "first DISE" (control group) was performed after polysomnography, while the "second DISE" (test group) performed immediately after a treadmill stress test. The two groups were compared for changes in degree and configuration of airway obstruction at the levels of the velum, oropharynx, tongue base, and epiglottis. There were several differences in DISE findings between the control and test groups. DISE findings obtained after the stress test revealed significant narrowing of multiple airway structures; upper airway narrowing was observed at the velum (19/48; 39.6%), oropharynx (31/63; 49.2%), and tongue base (9/61; 14.8%). Changes in configuration of upper airway obstruction were observed only at the level of the velum (33/85; 38.8%). Stress exercise test induces changes in the degree and configuration of upper airways narrowing, which causes surgeons to over or underestimate the obstructive pattern, depending on the clinical circumstance. When counseling patients on the likely value of sleep surgery based on DISE findings, stressful physical activity should be included as a contributing factor in treatment planning.