Sleep-disordered breathing (SDB) is increasingly recognized as a possible risk factor for adverse perioperative outcomes and although clinicians may expect SDB to be associated with increased risk of adverse postoperative outcomes after bariatric surgery, rates of postoperative complications after bariatric surgery have not been systematically compared in patients with and without SDB in a large, nationally representative sample.
To that end, we analyzed the Nationwide Inpatient Sample (NIS) database to quantify the impact of the diagnosis of SDB on in-hospital death, total charges, LOS, respiratory outcomes, and cardiac outcomes in 91,028 adult patients undergoing bariatric surgeries from 2004 to 2008. We found the prevalence of SDB to be 36% among patients undergoing elective bariatric surgery in the NIS database. After adjusting for important confounders, SDB was independently associated with significantly increased odds ratio of emergent endotracheal intubation, noninvasive ventilation, and atrial fibrillation. Moreover, emergent intubation occurred significantly earlier in the postoperative course in patients with SDB. These findings differ from what has been previously reported by Weingarten et al and the Longitudinal Assessment of Bariatric Surgery consortium who found that SDB was not associated with an increased likelihood of pulmonary complications in patients undergoing bariatric surgery. These 2 studies were performed in tertiary care academic centers whereas 42% of our patients had their surgery performed in a non-teaching hospital. Academic centers may have used multidisciplinary perioperative processes and pathways to identify and treat SDB more often than non-teaching hospitals.
Despite the increased association of SDB with postoperative complications, in our cohort the diagnosis of SDB was negatively associated with in-hospital mortality and resource use. SDB was independently associated with decreased mortality, total charges, and length of stay. Although non-SDB patients had an overall lower risk of emergent intubation compared to SDB patients, their outcomes were significantly worse when they did get emergently intubated. Other studies have demonstrated that SDB is not a risk factor for death in the postoperative bariatric setting, but why this association was in the opposite direction of what we expected is unclear. Our findings that SDB was not associated with increased length of stay and in-hospital mortality are in line with a recent single-center study by Lockhart et al of approximately 15, 000 presurgical patients.
In summary, using a large nationally representative database, we found that in patients undergoing bariatric surgery, SDB is independently associated with significant postoperative complications but not with increased in-hospital mortality, total charges, and length of stay.