Predicting Postoperative Leaks: A Preoperative Risk Index for Bariatric Surgery

The development of a staple line or anastomotic leak after sleeve gastrectomy (SG) or gastric bypass (RYGB) continues to be one of the most feared complications after bariatric surgery. Such leaks do not only affect the immediate management but are also associated with a significant increase in morbidity and mortality.

Using the data from the MBSAQIP database, we carried out a multivariate analysis and identified the most common risk factors for a leak after a primary bariatric surgery. Using the odds ratio (OR) of those factors, a risk index was developed, and a subsequent analysis was performed upon the index itself to determine the risk of a leak according to the number of points.

Data from 193,847 patients was analyzed, 140,605 had a SG (72.5%), and 53,242 had a RYGB (27.5%). A leak was present in 190 patients (0.1%) after SG and in 113 (0.2%) after RYGB. Statistically significant risk factors included: albumin < 3 g/dL (OR 3.196), previous foregut surgery (OR 2.827), preoperative therapeutic anticoagulation (OR 1.874), smoking (OR 1.776), hypertension (OR 1.404), sleep apnea (OR 1.322), and bypass surgery (OR 1.487). The risk of leak according to the number of points: 1 (OR 1.469), 2 (OR 2.066), 3 (OR 3.655), 4 (OR 3.609), 5 (OR 3.772), 6 (OR 4.075), 7 (OR 22.278).

As expected, the incremental number of factors increases exponentially the risk of a leak. Hypoalbuminemia, smoking, therapeutic anticoagulation and history of foregut surgery are the most significant risk factors. This score allows us to estimate more precisely the risk of a leak.