Surgical site infections in adults patients undergoing of clean and contaminated surgeries at a university Brazilian hospital

CONTEXT: Surgical site infections are a risk inherent to surgical procedures, especially after digestive surgeries. They occur up to 30 days after surgery, or up to a year later if a prosthesis is implanted. The Surgical-site Infection Risk Index (SIRI), NISS (National Nosocomial Infection Surveillance) methodology, is a method to evaluate the risk of surgical site infections, which takes into account the potential contamination of the surgery, the patient's health status and surgery duration. OBJECTIVES: To evaluate the correlation between the surgical-site infection risk index score on the 1st day postoperatively, and the development of surgical site infection up to 30 days postoperatively. METHODS: The postoperative surgical site infections (NNIS) was evaluated by following-up in hospital and as an outpatient. The patients followed prospectively were those submitted to elective surgeries, clean (hernioplasties) or contaminated (colorretal), performed by conventional approach at a university hospital, during the period from June 2007 to August 2008. The mean age of the patients was 55.5 years, 133 (65.5%) male; 120 (59.1%) submitted to clean surgeries and 83 (40.9%) contaminated. RESULTS: The global index of surgical site infections was 10.3%; 10 (8.3%) in clean procedures and 111(3.2%) in contaminated ones. Four (19.1%) of the surgical site infections were diagnosed at the time of hospitalization and 17 (80.9%) at post-discharge follow-up. Twelve (57.1%) of the surgical site infections were superficial, 2 (9.5%) deep and 7 (33.3%) at a specific site. Of these, 5 (6.6%) were in patients classified as SIRI 0 (76); 9 (15%) for SIRI 1 (60); 5 (9.1%) for SIRI 2 (55) and 2 (16.7%) for SIRI 3. CONCLUSION: The global index of surgical site infections and its incidence among contaminated procedures are within the expected limits. On the other hand according to SIRI, the surgical site infection indexes are above the expected standards both for the clean and for the contaminated procedures.