A microbiology study of the surgical site infection, at a hospital in northern Portugal

Surgical site infections (SSIs) remain a major clinical problem in terms of morbidity, mortality, time spent in hospital and overall direct and indirect costs. Objectives: To measure the prevalence of the SSI, by type of surgery and microbiologically characterization, in adult patients undergoing surgery during 2015 at a public hospital in northern Portugal. Methods: A prospective study, attended by 609 adult patients, undergoing surgery. The sociodemographic and clinical data of the population, as well as the surgical procedure and microbiological study were analyzed using Microsoft Access 2013. Results: In the sample of 609 adults undergoing surgery, it was found that 62.89% of surgical wound were cleaned, 15.8% were clean-contaminated, 8.70% were contaminated and 9.36% infected. About 62.52% of the intervened patients had antibiotic prophylaxis prior to surgery. Out of all surgeries, 33.3% were laparoscopic. The percentage of SSI was 5.74%; In these positive cases, only 3.61% was identiied the responsible bacteria. The urgent surgeries have more infections when compared to the programmed ones. In colon surgery the number of infections was 60% after cholecystectomy (22.86%). In hernioplasty, infection occurred in only 2.86% of the patients. The most isolated bacteria was Escherichia coli with 59%, in which 30% are -producing-lactamases of extended spectrum, followed by Pseudomonas aeruginosa (13.6%) and Serratia marcescens (13.6%). The mortality rate was 14.8%. Pseudomonas aeruginosa was isolated in 3 of 4 patients who died. Conclusions: The most microorganisms belong to the group of Gram-negative and are usually linked to infections associated with health care.