Effect of Intraoperative Hypothermia on Surgical Outcomes after Colorectal Surgery within an Enhanced Recovery after Surgery Pathway

Objective: The adverse effects of intraoperative hypothermia from the published literature were mainly based on non-enhanced recovery after surgery (ERAS) settings. This study aimed to determine association between intraoperative hypothermia and outcomes following colorectal surgery under ERAS pathway. Methods: A prospectively collected database of patients undergoing elective colorectal surgery under ERAS pathway from 2011 to 2015 was reviewed. Patients were divided into 2 groups: hypothermic group (core temperature <36oC continuously exceeding 30 minutes during an operation) and normothermic group. Short-term outcomes were compared. Results: This study included 195 patients: 150 (77%) in hypothermic group and 45 (23%) in normothermic group. Rectal surgery (OR=5.15), operative time exceeding 3 hours (OR=3.80), multi-organ resection (OR=3.12) and male gender (OR=2.62) were significant predictors for intraoperative hypothermia. Rates of postoperative complication and wound infection were comparable between hypothermic patients and normothermic patients (23% vs 13%; p=0.17 and 6.0 vs 6.7%; p=0.87, respectively). Hypothermic patients had a longer time to tolerate normal diet (2.0 days vs 1.3 days; p=0.023) but a comparable time to first bowel movement (2.6 days vs 2.6 days; p=0.84). Hypothermic patients had a significant longer hospitalization (5.7 days vs 4.4 days; p=0.048). A multivariate analysis showed that intraoperative hypothermia was an independent predictor for delayed food intake (OR=2.9, 95%CI=1.2-6.9; p=0.014) but not for prolonged hospitalization (OR=1.7, 95%CI=0.7-3.9; p=0.207). Conclusion: Intraoperative hypothermia prolonged time to tolerate food intake after colorectal surgery within an ERAS setting but it did not adversely affect the return of bowel function, wound infection, complication and length of hospitalization