Antimicrobial bowel preparation. Oral, parenteral, or both?

Area of Science:

• Surgical Infection Prevention
• Antimicrobial Prophylaxis
• Colorectal Surgery

Background:

• Wound infection rates post-colorectal surgery are a significant concern.
• The role of tissue antimicrobial levels versus intestinal bacterial colonization in surgical site infections is debated.
• Both factors are theoretically important in preventing postoperative complications.

Purpose of the Study:

• To compare the efficacy of purely parenteral antimicrobial prophylaxis with a combined oral and parenteral regimen in elective colorectal operations.
• To evaluate the impact of bowel preparation on bacterial growth and infection rates.
• To determine the optimal antimicrobial prophylaxis strategy for reducing surgical site infections.

Main Methods:

• A randomized controlled trial involving 119 patients undergoing elective colorectal surgery.
• Comparison between a group receiving parenteral antimicrobial prophylaxis and a group receiving combined oral and parenteral prophylaxis.
• Inclusion of data from 83 non-randomized patients who received the combined regimen.

Main Results:

• The combined oral and parenteral regimen significantly reduced the growth of fecal gram-negative aerobes and anaerobes in operation cultures compared to the parenteral-only group.
• Wound infection rates were significantly lower in the combined prophylaxis group (13.9%) versus the parenteral group (27.6%).
• While enterococci were more frequent in the combined group, this difference was not statistically significant.

Conclusions:

• Combined oral and parenteral antimicrobial prophylaxis is advisable for colorectal operations.
• Ensuring adequate tissue antimicrobial levels and partially decontaminating the bowel reduces the risk of endogenous bacterial infection.
• This strategy leads to significantly lower rates of wound infections after colorectal surgery.