WESTPORT, CT (Reuters Health) – Numerous risk factors influence the likelihood that patients will develop a surgical site infection after undergoing an elective colorectal resection, according to a report by Taiwanese investigators. Blood transfusion, however, is the only variable associated with infection at any site.
Dr. Jeng-Yi Wang and colleagues, from the Chang Gung Memorial Hospital in Linkou, Taipei, identified risk factors for surgical site infection by analyzing data from 2809 patients who underwent an elective colorectal resection between February 1995 and December 1998.
Nearly 5% of patients developed some form of infection at the surgical site, the authors report in the August issue of the Annals of Surgery. The rates of incisional site infection and organ/space infection with clinical anastomotic leakage were 4.7% and 3%; in the absence of leakage, the rates were 2%, and 0.8%, respectively.
Patient characteristics associated with an elevated overall risk of infection included high American Society of Anesthesiology scores and male gender. Surgical factors that were linked to an increased risk included creation of an ostomy, presence of a contaminated wound, use of drainage, and intra- or postoperative blood transfusion.
The overall surgical site infection rates of the seven surgeons involved in the study ranged from 2.2% to 9.1%, the authors note.
Abdominoperineal resection was associated with the lowest overall infection rate, while total/subtotal colectomy was tied to the highest overall rate. The importance of a given risk factor varied by operative site. "Only blood transfusion was consistently associated with a risk of surgical site infection at any specific site," the investigators report.
"This series of postoperative surgical site infections is the largest single-center prospective study to date in colorectal surgery," Dr. Wang's team points out. "When assessing risk factors for surgical site infection, the distinction between incisional surgical site infection and organ/space SSI with or without leakage is of clinical and pathogenetic importance because the risk factors differ from each other," they add.