Study objectives: This study was conducted to determine whether postoperative complications are increased in patients with obstructive sleep apnea (OSA) and to study the impact of the severity of OSA and preoperative use of continuous positive airway pressure (CPAP) on the postoperative outcome.
Design and setting: This study is retrospective in nature and was undertaken at the VA Medical Center.
Participants and methods: Three hundred seventy patients who had undergone both a major surgical procedure and a sleep study from 2000 to 2010 were identified. Patients were divided into four groups: OSA negative (apnea-hypopnea index (AHI) < 5/h), OSA positive; mild: AHI 5 to <15/h; moderate: AHI 15 to <30/h; and severe: AHI ≥ 30/h. No intervention was made during the course of the study. Postoperative complications namely respiratory, cardiac, neurological, and unplanned intensive care unit transfers were collected.
Results: There were 284 (76.8 %) patients having OSA and 86 (23.2 %) without OSA. The overall incidence of total complications was significantly higher in the OSA patients compared with the control patients (48.9 vs. 31.4 %; odds ratio 2.09, 95 % CI 1.25-3.49). There was no significant difference in total complications between those using and not using CPAP prior to hospitalization. Patients with sleep apnea had a higher incidence of respiratory complications compared to patients without sleep apnea (40.4 vs. 23.2 %; odds ratio 2.24, 95 % CI 1.29-3.90). There was no significant difference in major cardiac complications in the OSA patients compared with the control patients (13.0 vs. 9.3 %; odds ratio 1.46, 95 % CI 0.65-3.26).
Conclusion: OSA is associated with a significantly increased rate of postoperative complications.