Prevalence of adverse intraoperative events during obesity surgery and their sequelae.

Background: Adverse intraoperative events (AIEs) during surgery are a well-known entity. A better understanding of the incidence of AIEs and their relationship with outcomes is helpful for surgeon preparation and preoperative patient counseling. The goals of this study are to describe the incidence of AIEs during bariatric surgery and examine their impact on major adverse complications.

Study Design: The study included 5,882 subjects who had bariatric surgery in the Longitudinal Assessment of Bariatric Surgery study between March 2005 and April 2009. Prospectively collected AIEs included organ injuries, anesthesia-related events, anastomotic revisions, and equipment failure. The relationship between AIEs and a composite end point of 30-day major adverse complications (ie, death, venous thromboembolism, percutaneous, endoscopic, or operative reintervention and failure to be discharged from the hospital within 30 days from surgery) was evaluated using a multivariable relative risk model adjusting for factors known to influence their risk.

Results: There were 1,608 laparoscopic adjusted gastric banding, 3,770 laparoscopic Roux-en-Y gastric bypass operations, and 504 open Roux-en-Y gastric bypass operations. Adverse intraoperative events occurred in 5% of the overall sample and were most frequent during open Roux-en-Y gastric bypass (7.3%), followed by laparoscopic Roux-en-Y gastric bypass (5.5%) and laparoscopic adjusted gastric banding (3%). The rate of composite end point was 8.8% in the AIE group compared with 3.9% among those without an AIE (p < 0.001). Multivariable analysis revealed that patients with an AIE were at 90% greater risk of composite complication than those without an event (relative risk = 1.90; 95% CI, 1.26-2.88; p = 0.002), independent of the type of procedure (open or laparoscopic).

Conclusions: Incidence of an AIE is not infrequent during bariatric surgery and is associated with much higher risk of major complication. Additional study is needed to assess the association between specific AIEs and short-term complications.