Oral plus IV antibiotic reduces SSIs by more than 50 pc in patients undergoing colorectal surgery: JAMA

New Zealand: A recent study in the journal JAMA Surgery has demonstrated that the addition of oral antibiotics (OA) to intravenous antibiotics may reduce surgical site infections (SSI) in patients undergoing elective colorectal surgery. The results support the addition of OA to IV antibiotics in the bowel preparation for reducing incisional SSI. 

There seems to be no clarity on the best method of bowel preparation for colorectal surgery among patients undergoing elective colorectal surgery. Usually, IV antibiotics are administered but the use of mechanical bowel preparation (MBP), enemas, and/or oral antibiotics (OA) is controversial. To overcome these discrepancies, John C. Woodfield, University of Otago, Dunedin, New Zealand, and colleagues aimed to summarize all data from randomized clinical trials (RCTs) that met selection criteria using network meta-analysis (NMA) to determine the ranking of different bowel preparation treatment strategies for their associations with postoperative outcomes. 

RCTs were selected by multiple reviewers and adjudicated by a separate lead investigator. RCTs of adults undergoing elective colorectal surgery with an appropriate aerobic and anaerobic antibiotic cover that reported on incisional surgical site infection or anastomotic leak were selected for inclusion. A total of 167 of 6833 screened studies met initial selection criteria. 

Primary outcomes were incisional SSI and anastomotic leak. Secondary outcomes included other infections, mortality, ileus, and adverse effects of preparation.

  A total of 35 RCTs that included 8377 patients were identified.

Treatments compared IV antibiotics (2762 patients [33%]), IV antibiotics with enema (222 patients [3%]), IV antibiotics with OA with or without enema (628 patients [7%]), MBP with IV antibiotics (2712 patients [32%]), MBP with IV antibiotics with OA (with good IV antibiotic cover in 925 patients [11%] and with good overall antibiotic cover in 375 patients [4%]), MBP with OA (267 patients [3%]), and OA (486 patients [6%]). 

"The main finding of this NMA was that adding IV + OA resulted in a significant reduction in SSI by greater than 50% compared with other options. This was the case both with and without MBP," wrote the authors. 

The results support the addition of OA to IV antibiotics to reduce incisional SSI among patients undergoing elective colorectal surgery, they concluded.

Reference:

Woodfield JC, Clifford K, Schmidt B, Turner GA, Amer MA, McCall JL. Strategies for Antibiotic Administration for Bowel Preparation Among Patients Undergoing Elective Colorectal Surgery: A Network Meta-analysis. JAMA Surg. Published online October 20, 2021. doi:10.1001/jamasurg.2021.5251