Rebecca Pascoe (BN, MN) is a 5th year Medical Student at the University of Otago Christchurch, and has a prior background in Nursing and Surgical research. She was the Local Student Lead in Christchurch for the IMAGINE study.
Effect Of Opiate Analgesia On Post-Operative Gastrointestinal Recovery: Australasian Results Of The IMAGINE (Ileus Management International) Study
Introduction Opiate analgesia is often implicated in the pathogenesis of post-operative ileus (POI), though few studies have quantified the effect of opiates on gastrointestinal (GI) recovery. This study aimed to determine the effect of opiate analgesia on POI in patients undergoing elective colorectal surgery.
Method A multicentre, prospective, observational study of patients undergoing elective colorectal resection or reversal of stoma was undertaken at 28 hospitals in New Zealand and Australia. Daily opiate consumption was recorded until post-operative day seven, and was analysed as oral morphine-equivalents (ME). The primary outcome was time until GI-2 (tolerance of oral diet and passage of stool). Data were validated for accuracy by independent investigators.
Results In total, 283 patients were included. The median time for GI recovery was 4 days (IQR 2.5-5.5). The most frequently-used opiate was fentanyl (62%), followed by oxycodone (50%) and morphine (35%). No opiate analgesia was received by 32 patients (11%). Multivariate analysis identified prolonged GI recovery was independently predicted by >85 ME parenteral opiate in the first 7 days post-operatively (HR 0.70, 95% CI 0.52-0.95, p=0.02), but not oral opiate use. Use of an epidural (HR 0.47, 95% CI 0.29-0.76, p=0.002), and occurrence of anastomotic leak (HR 0.50, 95% CI 0.31-0.79, p=0.003) or pneumonia (HR 0.36, 95% CI 0.19-0.70, p=0.003) predicted prolonged GI recovery. Patients undergoing reversal of stoma had a significantly shorter recovery (HR 1.51, 95% CI 1.04-2.21, p=0.03).
Conclusion A dose-dependent relationship exists between opiate analgesia and post-operative ileus. Further work should explore opiate-sparing regimens for post-operative patients.