The Association of Immediate-Use Steam Sterilization with the Incidence of Orthopaedic Surgical Site Infections

Abstract

Background: Immediate-use steam sterilization (IUSS), formerly termed “flash” sterilization, has been historically used to sterilize surgical instruments in emergency situations. Strict guidelines deter its use, as IUSS has been theorized to increase the risk of surgical site infections (SSIs), leading to increased health-care costs and poor patient outcomes. We sought to examine the association between the use of IUSS and the rate of orthopaedic SSIs. Methods: The cases of 70,600 patients who underwent orthopaedic surgery—total knee or hip arthroplasty, laminectomy, or spinal fusion—from January 2014 to December 2020, were retrospectively reviewed for IUSS use. Of this group, 3,526 patients had had IUSS used during surgery. A propensity score-matched (PSM) analysis was conducted to account for known predictors of SSIs and included a total of 7,052 patients. The risk difference (RD), relative risk (RR), odds ratio (OR), and McNemar test compared the SSI risk for patients whose procedure had included the use of IUSS and those whose procedure had not included IUSS. Results: After propensity score matching, 111 (1.57%) of the 7,052 matched patients developed an SSI. Of the 111 patients, 61 (54.95%) were in the IUSS group and 50 (45.05%) were in the non-IUSS group. The estimated probability for developing an SSI was 1.42% for the patients in the non-IUSS group versus 1.73% for the patients in the IUSS group (RR = 0.82 [95% confidence interval (CI)]: 0.57 to 1.19], RD = –0.3% [95% CI: –0.9% to 0.27%]).There was no evidence that the proportion of SSI was greater in the IUSS group (McNemar test, p > 0.29). Conclusions: SSI rates were not significantly different between IUSS and non-IUSS patients undergoing orthopaedic surgery. Future prospective studies are warranted to further explore the utility of IUSS during orthopaedic procedures. Level of Evidence: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.