The Impact of Untreated Obstructive Sleep Apnea on Cardiopulmonary Complications in General and Vascular Surgery: A Cohort Study

Study objective: To determine whether preoperatively untreated obstructive sleep apnea (OSA) affects postoperative outcomes.

Design: Cohort study of patients undergoing surgery between July 2012 and September 2013, utilizing prospectively collected data from the Michigan Surgical Quality Collaborative. Multivariable regression models were used to compare complication rates between treated and untreated OSA, while adjusting for important patient covariates and clustering within hospitals.

Setting: Fifty-two community and academic hospitals in Michigan.

Patients: Adult patients undergoing various general or vascular operations were categorized as: (1) no diagnosis or low risk of OSA; (2) documented OSA without therapy or suspicion of OSA; and (3) diagnosis of OSA with treatment (e.g., positive airway pressure).

Exposures: OSA, preoperatively treated or untreated, was the exposure variable. Postoperative 30-day cardiopulmonary complications including arrhythmias, cardiac arrest, myocardial infarction, unplanned reintubation, pulmonary embolism, and pneumonia were the outcomes of interest.

Measurements and results: Of 26,842 patients, 2,646 (9.9%) had a diagnosis or suspicion of OSA. Of those, 1,465 (55.4%) were untreated. Patient and procedural risk factors were evenly balanced between treated and untreated groups. Compared with treated OSA, untreated OSA was independently associated with more cardiopulmonary complications (risk-adjusted rates 6.7% versus 4.0%; adjusted odds ratio [aOR] = 1.8, P = 0.001), particularly unplanned reintubations (aOR = 2.5, P = 0.003) and myocardial infarction (aOR = 2.6, P = 0.031).

Conclusions: Patients with obstructive sleep apnea (OSA) who are not treated with positive airway pressure preoperatively are at increased risks for cardiopulmonary complications after general and vascular surgery. Improving the recognition of OSA and ensuring adequate treatment may be a strategy to reduce risk for surgical patients with OSA.