The Efficacy and Safety of Using Collagen Patch on Anastomotic Site in Colorectal Surgery

Wound healing occurs in four distinct phases: hemostasis, inflammation, proliferation, and tissue remodeling. Numerous factors can influence these phases, which can be classified as either local or systemic. Local factors include infection, presence of foreign bodies, inadequate oxygenation, and other issues affecting the wound itself, while systemic factors encompass a wide range of considerations such as age, gender, presence of systemic disease, ischemia, stress, medication use, obesity, cigarette and alcohol use, nutritional status, and immunocompromised conditions.

Anastomotic healing in the colon is similar to the healing process in skin while there's still some differences. While the cellular and histological processes involved in colonic healing are well known, the pathophysiological process is not fully understood and requires further studies . Unlike skin healing, the process of patients undergoing colonic resection and anastomosis healing can only be inferred by observing certain parameters, such as amount of drainage, time to first flatus and defecation and the patient's symptoms. These parameters are used to guide the patient's recovery program. Complications such as anastomotic leakage, bleeding or stricture would lead to longer hospital stay, mortality and morbidity. The most devastating one is anastomotic leakage. Although we have found some strategies to lower the rate in colorectal surgery such as colon preparation or antibiotics administration, the leakage still bothers a lot.

Besides controlling the local and systemic factors, several biomaterial products have been designed to progress the healing. Collagen plays crucial roles in all of the four healing phases. As a result, collagen wound dressing, derived from bovine, equine, avian or porcine, has been applied in different sites of wound to promote healing. Several studies have concluded that collagen wound dressing resulted in better outcomes but limited to in vitro studies or animal based research. Pantelis D. concluded that fibrin in combination with the collagen patch can improve healing in high-risk mice that underwent colonic anastomosis surgery. Pommergaard HC. also concluded that the collagen wound dressing can lower the leakage rate in mouse colon anastomosis surgery.

Another limitation is that most studies have small sample sizes and lack of long term observation. Parker et al designed a non-randomized study and concluded that collagen wound dressing is safe and easy to apply in human colorectal surgery. Marano et al compared the complication rate of two cohorts and revealed that collagen wound dressing can lower the complication rate in the patients who underwent upper gastrointestinal surgery. As of now, it is premature to conclude that collagen wound dressing is effective in human colonic anastomosis due to the lack of human studies and larger sample size. In order to investigate the effects of collagen wound dressing on colonic anastomosis during colectomy, we conducted a retrospective cohort study. Our goal was to determine whether the use of collagen wound dressing results in improving clinical outcomes for patients undergoing laparoscopic colectomy.