Differences in short-term outcomes among patients undergoing IPAA with or without preoperative radiation: a National Surgical Quality Improvement Program analysis.

BACKGROUND: Single-institution studies demonstrate a correlation between preoperative pelvic radiation and poor long-term pouch function after IPAA. The rarity of the radiated pelvis before these procedures limits the ability to draw conclusions on the effects of preoperative radiation on short-term outcomes, which may contribute to long-term pouch dysfunction. OBJECTIVE: The purpose of this work was to better understand the impact of pelvic radiation on short-term outcomes in patients undergoing IPAA. DESIGN: We conducted a retrospective review of the American College of Surgeons National Surgical Quality Improvement Program database (2005-2011). SETTINGS: The study was conducted at all participating NSQIP institutions. PATIENTS: The cohort was composed of patients undergoing nonemergent IPAA procedures. MAIN OUTCOME MEASURES: Proportions of patients experiencing postoperative complications within 30 days were compared by Fisher exact and Wilcoxon rank-sum tests based on whether they received preoperative radiation. Multivariate logistic regression models controlled for the effects of multiple risk factors. RESULTS: Included were 3172 patients receiving IPAA; 162 received pelvic radiation. The postoperative complication rate was not significantly different in patients receiving pelvic radiation versus not receiving pelvic radiation (p = 0.06). In a subset of patients with cancer diagnoses (n = 598), 157 received pelvic radiation; complication rates were not significantly different (p = 0.16). Patients receiving pelvic radiation had significantly lower rates of sepsis in both the overall and cancer diagnosis groups (p = 0.005 and p = 0.047), a finding which persisted after controlling for the effects of multiple risk factors (multivariate p values = 0.030 and 0.047). LIMITATIONS: This was a retrospective database design with short-term follow-up. CONCLUSIONS: Patients who received radiation before IPAA had no difference in overall 30-day complication rates but had significantly lower rates of sepsis when compared with patients not receiving pelvic radiation. The perceived inferior long-term pouch function in patients undergoing preoperative pelvic radiation does not appear to be attributable to increases in 30-day complications.