The Impact of Cefazolin Shortage on Surgical Site Infection Following Spine Surgery in Japan

Study design Retrospective study using prospectively collected data. Objective This study aimed to investigate the effect of alternative antimicrobial prophylaxis agents on surgical site infections (SSIs) after spine surgery. Summary of background data Although the use of alternative antimicrobial prophylaxis agents might have a negative effect on SSI prevention, their association with SSI risk in spine surgery remains unclear. Methods We used the registry data of consecutive patients undergoing spine surgery from April 2017 to January 2020 in four institutions participating in the University of Tokyo Spine Group. Before March 2019, all institutions used cefazolin for antimicrobial prophylaxis. After March 2019, the institutions used broad-spectrum beta-lactam agents as an alternative due to a cefazolin shortage in Japan. Results Among the 3841 enrolled patients (2289 males), 2024 received cefazolin and 1117 received alternative agents. The risk of reoperation for deep SSI within 30 days of spine surgery was significantly higher in the alternative antimicrobial prophylaxis agent group (adjusted odds ratio [aOR] 1.96; 95% confidence interval [CI], 1.15-3.35; P = 0.014). In subgroup analyses, the SSI risk was significantly higher in the thoracolumbar surgery group (aOR 1.98; 95% CI, 1.06-3.73; P = 0.03). A nonsignificant consistent trend was found in all other subgroups: posterior decompression (aOR 1.91; 95% CI, 0.86-4.21; P = 0.11); posterior fixation (aOR 2.05; 95% CI, 0.99-4.24; P = 0.05); and cervical spine surgery (aOR 2.30; 95% CI, 0.82-6.46; P = 0.11). Conclusion Alternative antimicrobial prophylaxis agents increased the risk of reoperation for SSI after spine surgery compared with cefazolin. Our study supports the current practice of using first-generation cephalosporins as first-line antimicrobial prophylaxis agents in spine surgery as recommended in multiple guidelines.Level of Evidence: 3.