MELD-Na Score as a Predictor of Anastomotic Leak in Elective Colorectal Surgery.

Background: For cirrhotic patients awaiting liver transplantation, the Model for End-Stage Liver Disease Sodium (MELD-Na) model is extensively studied. Because of the simplicity of the scoring system, there has been interest in applying MELD-Na to predict patient outcomes in the noncirrhotic surgical patient, and MELD-Na has been shown to predict postoperative morbidity and mortality after elective colectomy. Our aim was to identify the utility of MELD-Na to predict anastomotic leak in elective colorectal cases.

Methods: The American College of Surgeons National Surgical Quality Improvement Program targeted colectomy database was queried (2012-2014) for all elective colorectal procedures in patients without ascites. Leak rates were compared by MELD-Na score using chi-square tests and multivariate logistic regression analysis.

Results: We identified 44,540 elective colorectal cases (mean age, 60.5 y ± 14.4, mean body mass index 28.8 ± 6.6 kg/m, 52% female), of which 70% were colon resections and 30% involved partial rectal resections (low anterior resections). Laparoscopic approach accounted for 64.72% while 35.3% were open. The overall complication and mortality rates were 21% and 0.7%, respectively, with a total anastomotic leak rate of 3.4%. Overall, 98% had a preoperative MELD-Na score between 10 and 20. Incremental increases in MELD-Na score (10-14, 15-19, and ≥20) were associated with an increased leak rate, specifically in partial rectal resections (3.9% versus 5.1% versus 10.7% P <0.028). MELD-Na score ≥20 had an increased leak rate when compared with those with MELD-Na 10-14 (odds ratio [OR] 1.627; 95% confidence interval [CI] [1.015, 2.607]). An MELD-Na score increase from 10-14 to 15-19 increases overall mortality (OR 5.22; 95% CI [3.55, 7.671]). In all elective colorectal procedures, for every one-point increase in MELD-Na score, anastomotic leak (OR 1.04 95% CI [1.006, 1.07]), mortality (OR 1.24; 95% CI, [1.20, 1.27]), and overall complications (OR 1.10; 95% CI [1.09, 1.12]) increased. MELD-Na was an independent predictor of anastomotic leak in partial rectal resections, when controlling for gender, steroid use, smoking, approach, operative time, preoperative chemotherapy, and Crohn's disease (OR 1.06, 95% CI [1.002, 1.122]).

Conclusions: MELD-Na is an independent predictor of anastomotic leak in partial rectal resections. Anastomotic leak risk increases with increasing MELD-Na in elective colorectal resections, as does 30-d mortality and overall complication rate. As MELD-Na score increases to more than 20, restorative partial rectal resection has a 10% rate of anastomotic leak.