Effects of multilevel OSA surgery on patients with poor cardiopulmonary performance: A prospective pilot study.

Objective: Multilevel airway surgery for obstructive sleep apnea/hypopnea syndrome (OSA) has benefits in improving sleep quality, but its effect on polysomnography (PSG) and 6-minute walk test (6MWT) parameters, including walking distance and cardiopulmonary performance, in patients with poor pre-operative cardiopulmonary performance remains understudied, which should be further investigated.

Methods: This prospective pilot study enrolled 27 consecutive OSA patients with poor pre-operative 6MWT results. All patients received multilevel OSA surgery, and the alterations of sleep parameters and 6MWT profiles were studied. The pre- and post-operative values of polysomnographic data and 6MWT profiles were analyzed using the Wilcoxon signed-rank tests. The relationships among changes of the indices of PSG and 6MWT were further investigated with the Spearman's correlations.

Results: After surgery, the sleep parameters and certain cardiopulmonary indices improved. When analyzing the correlations among changes of the indices of PSG and 6MWT, the improvement of daytime sleepiness (with ESS) was found related to farther walking distance (ρ=-0.414, p = 0.032) and higher percentage of "distance/target distance" (ρ=-0.435, p = 0.023). Moreover, the change of maximal expiratory pressure was the only index associated with the changes of AHI (apnea/hypopnea index, /hr.; ρ=-0.407, p = 0.035) and AHI in REM (ρ=-0.502, p = 0.009) among the cardiopulmonary performance parameters.

Conclusion: This pilot study showed that OSA patients with poor pre-operative cardiopulmonary status undergoing multilevel sleep surgery could experience improvement in the sleep study and 6MWT to some extent. The relatively better walking distance and cardiopulmonary performance after the operation might potentially result from the improvement of daytime sleepiness and better respiration.