Evaluating Risk Factors of Surgical Site Infection After Surgery in Orthopedic Patients of Dr. Shariati Hospital, During 2006 - 2012

Abstract

Background: Surgical site infection (SSI) is defined as an infection that occurs at or near a surgical incision, within 30 days of the procedure, or within one year, if an implant is left in place. They are the leading cause of nosocomial infections after surgery, accounting for nearly 40% of nosocomial infections in surgical patients. Identifying the risk factors that increase the probability of SSI can help us take preventive measures and design control strategies, leading to a decrease in the rate of infection.
Objectives: We aimed to assess the effects of probable SSI risk factors, making it possible to control these variables and to avoid complications of SSI, thereby decreasing its direct and indirect costs.
Patients and Methods: In this nested case-control retrospective study, 208 patients, who underwent orthopedic surgery in Dr. Shariati Hospital, Tehran, Iran, during 2006 - 2012, were included, as the study population. Data were gathered from the patients’ records and were analyzed by SPSS v.20 software via independent samples t test, chi-square test and binary logistic regression analysis.
Results: The mean age of the study population was 40.88 years, with a 2-year-old, as the youngest subject, and an 85-year-old, as the oldest. Statistical significance was achieved at a P < 0.05 and the differences observed between the two groups of SSI+ and SSI- were found to be statistically significant regarding opium addiction (P = 0.035), smoking (P = 0.009), blood transfusion (P < 0.001), duration of surgery (P = 0.003), duration of hospitalization (P = 0.013). According to multivariate logistic regression analysis, independent risk factors of SSI included smoking (P = 0.002, OR = 0.35) and blood transfusion (P = 0.001, OR = 0.24).
Conclusions: We found smoking and blood transfusion to be independent risk factors for SSI, whereas, regarding the disagreements between the results of various studies, further investigations are required to identify absolute independent risk factors of SSI.