Plastic wound retractors as bacteriological barriers in gastrointestinal surgery: a prospective multi-institutional trial.

BACKGROUND Surgical site infection remains a significant problem, and peri-operative strategies to reduce wound exposure to bacteria are needed urgently. Plastic ring wound retractors, used to gain access to the abdominal cavity, may shield the incision site from bacteria. AIM To evaluate exposure of the surgical incision site to bacteria using a plastic ring wound retractor in gastrointestinal surgery. METHODS Prospective, observational, multi-centre study. Patients undergoing clean-contaminated gastrointestinal surgery with standard antibiotic prophylaxis were included (N = 250 patients, 500 samples). A plastic wound retractor was used to facilitate access to the abdominal cavity. Samples were taken for bacterial culture from the inside (luminal) and outside (wound) surfaces of the retractor at the end of the operation. FINDINGS Bacteria were found on 56% (140/250) of samples from the inside surface of the retractor compared with 34% (85/250) of samples from the outside surface of the retractor (P < 0.0001). There was no significant difference in skin-derived organisms from the inside [34/245 (14%)] and outside [27/250 (11%)] surfaces of the retractor (P = 0.108). However, enteric organisms were cultured twice as often from the inside surface of the retractor compared with the outside surface of the retractor (49% vs 26%, respectively; P < 0.0001). CONCLUSION Plastic wound retractors reduce wound exposure to enteric bacteria in gastrointestinal surgery.