Surgical site infections in ambulatory surgery: a 5-year experience.

OBJECTIVES

To evaluate the ambulatory surgical site infection rate and risk factors associated with surgical site infection.

METHODS

We conducted a case-control analysis of all ambulatory surgeries between January 1, 1993, and December 31, 1997. The frequency of surgical site infection per 100 surgeries was calculated. The odds ratio (OR) was estimated by using logistic regression analysis.

SETTING

A 140-bed tertiary-care teaching hospital for adult patients with cancer.

RESULTS

The study followed 1350 outpatient surgeries. Thirty-eight patients had a surgical site infection (rate per 100 surgeries: 2.8). The risk factors statistically associated with surgical site infection were postoperative antibiotics (OR = 7.5; 95% CI, 2.5-23.0), and surgical time >35 minutes (OR = 2.4; 95% CI, 1.1-5.5).

CONCLUSIONS

The surgical site infection rate for same-day surgery at our hospital is within the limits reported in the literature and below the rates reported previously for inpatient surgeries at our hospital. Full review of medical records and microbiology reports at day 30 allowed us to identify infections that otherwise would have been missed. Postoperative antibiotics may increase the risk of infection.