Mechanical bowel preparation versus no preparation in elective colorectal surgery: A prospective randomized study

Background: Mechanical bowel preparation (MBP) of gut is routinely done before colorectal surgeries in most surgical departments all over the globe. This gut preparation is aimed at reducing the risk of postoperative infections in patients undergoing colorectal surgery. Even though recent studies are more in favor of operating on gut without bowel preparation, controversies still exist. The aim of our study was to assess whether elective colorectal surgeries can be performed safely without preoperative MBP. Methods: Patients undergoing elective colorectal surgeries were prospectively randomized into two groups with the help of random number table method; Group-1 had mechanical bowel preparation with polyethylene glycol (MBP group) before surgery, and Group-2 had no mechanical bowel preparation (NMBP group) before surgery. All patients in the study groups were followed up for at least 2 months after surgery for wound infection, anastomotic leak and intra-abdominal infections. Results: Two hundred fourteen patients were included in this hospital-based systematic prospective randomized trial: 104 patients in Group-1 and 98 patients in Group-2. Twelve patients were excluded from the study. The type of surgical procedure and type of anastomosis did not significantly differ between two groups. There was no difference in surgical infections between two groups. The overall infection rate was 39.4% in Group-1 and 32.6% in Group-2 (p = 0.31). Wound infection (p = 0.45), anastomotic leak (p = 0.45) and intra-abdominal/pelvic collection (p = 0.62) occurred in 3.8%, 3.8% and 6.7% versus 6.1%, 2% and 5.1% in Group-1 (MBP group) and Group-2 (NMBP group) respectively. Our results showed that MBP does not offer any specific benefit in elective colorectal surgeries but in real sense may add to some problems, which, however, did not achieve a statistical significance. Conclusions: Our study proved that no advantage is gained by pre-operative mechanical bowel preparation in elective colorectal surgery and can be easily avoided in order to save patients from unwanted exhaustion, distress and adverse effects related to it. It is actually the mindset that makes us to believe that MBP will reduce the incidence of infections rather than the evidence from literature. We conclude from our study that all types of elective colorectal surgeries can be performed safely without subjecting patients to mechanical bowel preparation before surgery. (C) 2016 Published by Elsevier Ltd on behalf of Surgical Associates Ltd.