Anesthetic management and surgical site infections in total hip or knee replacement: a population-based study

Epidural or spinal anesthesia involves several mechanisms hypothesized to reduce risk of surgical site infections (SSIs) during this decisive period. This study aims to compare the risk of SSI within 30 days of surgery for patients receiving total hip or knee replacement under general anesthesia versus those under epidural or spinal anesthesia.

We used the Longitudinal Health Insurance Database of Taiwan. A total of 3,081 patients who underwent primary total hip or knee replacement from 2002 to 2006 were included in the study. Multivariate logistic regression and propensity score analyses were carried out to explore the relationship between method of surgical anesthesia and SSI occurring within 30 days of surgery.

Of the 3,081 sampled patients, 56 patients (1.8%) had 30-day SSIs; 33 (2.8% of all under general anesthesia) of them had general anesthesia, and 23 (1.2% of all under epidural or spinal anesthesia) had epidural or spinal anesthesia (P = 0.002). The odds of SSI for patients receiving total hip or knee replacement under general anesthesia were 2.21 (95% CI = 1.25-3.90, P = 0.007) times higher than those who had the same procedure under epidural or spinal anesthesia, after adjusting for the patient's age, sex, the year of surgery, comorbidities, surgeon's age, and hospital teaching status.

Total hip or knee replacement under general anesthesia is associated with higher risk of SSI compared with epidural or spinal anesthesia. Our results support the evolving concept of long-term consequences of anesthesia and emphasize the anesthesiologist's role in preventing SSIs.