Disparities in the regional, hospital and individual levels of antibiotic use in gallstone surgery in Sweden

BACKGROUND: Antimicrobial resistance may be promoted by divergent routines and lack of conformity in antibiotic treatment, especially regarding the practice of antibiotic prophylaxis. The aim of the present study was to assess differences in gallstone surgery regarding antibiotic use in Sweden. METHODS: The study was based on data from the Swedish Register for Gallstone Surgery and ERCP (GallRiks) 2005–2015. Funnel plots were used to test impact of grouping factors, including, hospital and surgeon and to identify units that deviated from the rest of the population. RESULTS: After adjusting for cofounders including age, gender, ASA classification, indication for surgery, operation time, gallbladder perforation and emergency status, there were 0/21 (0%) at the regional level, 18/76 (24%) at the hospital level and 128/1038 (12%) at the surgeon level outside the 99.9% confidence interval (CI). The estimated median odds ratios were 1.13 (95% CI 1.00–1.31) at the regional level, 1.93 (95% CI 1.70–2.19) at the hospital level and 2.38 (95% CI 2.26–2.50) at the surgeon level. CONCLUSION: There are significant differences between hospitals and surgeons, but little or no differences between regions. These deviations confirm the lack of standardization in regards to prescription of antibiotic prophylaxis and the need more uniform routines regarding antibiotic usage. Randomized controlled trials and large population-based studies are necessary to assess assessing the effectiveness and safety of antibiotic prophylaxis in gallstone surgery.