Colorectal surgery outcomes in chronic dialysis patients

BACKGROUND: More than 450,000 US patients with end-stage renal disease currently dialyze. The risk of morbidity and mortality for these patients after colorectal surgery has been incompletely described. OBJECTIVE: We analyzed the 30-day morbidity and mortality rates of chronic dialysis patients who underwent colorectal surgery. DESIGN: This was a retrospective analysis. SETTINGS: Hospitals that participate in the American College of Surgeons National Surgical Quality Improvement Program were included. PATIENTS: The study included adult patients who underwent emergency or elective colon or rectal resection between 2009 and 2014. MAIN OUTCOME MEASURES: Baseline characteristics were compared by dialysis status. The impact of chronic dialysis on 30-day mortality and serious postoperative morbidity was examined using multivariate logistic regression. RESULTS: We identified 128,757 patients who underwent colorectal surgery in the American College of Surgeons National Surgical Quality Improvement Program database. Chronic dialysis patients accounted for 1% (n = 1285) and were more likely to be older (65.4 vs 63.2 years; p < 0.0001), black (27.2% vs 8.7%; p < 0.0001), preoperatively septic (22.1% vs 7.1%; p < 0.0001), require emergency surgery (52.0% vs 14.7%; p < 0.0001), have ischemic bowel (15.7% vs 1.6%; p < 0.0001), or have perforation/peritonitis (15.5% vs 4.2%; p < 0.0001). Chronic dialysis patients were also less likely to have a laparoscopic procedure (17.3% vs 45.0%; p < 0.0001). Chronic dialysis patients had higher unadjusted mortality (22.4% vs 3.3%; p < 0.0001), serious postoperative morbidity (47.9% vs 18.8%; p < 0.0001), and median length of stay (9 vs 6 days; p < 0.0001). In emergent cases (n = 19,375), multivariate logistic regression models demonstrated a higher risk of mortality for dialysis patients (OR = 1.73 (95% CI, 1.38-2.16)) but not for serious morbidity. Models for elective surgery demonstrated a similar effect on mortality (OR = 2.47 (95% CI, 1.75-3.50)) but also demonstrated a higher risk of serious morbidity (OR = 1.28 (95% CI, 1.04-1.56)). LIMITATIONS: The postoperative 30-day window may underestimate the true incidence of serious morbidity and mortality. CONCLUSIONS: Chronic dialysis patients undergoing elective or emergent colorectal procedures have a higher risk-adjusted mortality.