RESUMO
BACKGROUND: The US Centers for Medicare and Medicaid Services provide guidelines for the coverage of anaesthesia residents and certified registered nurse anaesthetists (CRNAs) by anaesthesiologists. We tested the hypothesis that changes in the anaesthesia staffing model increase billing compliance. METHODS: We analysed 13 926 anaesthesia cases performed between September 2019 and November 2019 (baseline), and between September 2020 and November 2020 (after change in staff model) at a US academic medical centre using an estimation tool. The intervention was assignment of additional 12-h weekday CRNAs plus an additional anaesthesiologist who covered weekdays after 17:00, weekends, and holidays. The proportion of cases with billing compliant coverage (covered either by solo anaesthesiologist or anaesthesiologist covering two or fewer residents or four or fewer CRNAs) was analysed using logistic and segmented regression analyses. RESULTS: The change in staff model was associated with a decrease in non-optimal anaesthesia staff assignments from 4.2% to 1.2% of anaesthesia cases (adjusted odds ratio 0.25; 95% confidence interval [CI] 0.20-0.32; P<0.001) and an increase in billable anaesthesia units of 0.6 per anaesthesia case (95% CI 0.4-0.8; P<0.001). An increased revenue margin associated with optimal staffing levels would only be achieved with salary levels at the 25th percentile of relevant benchmark compensation levels. Total staff overtime for all anaesthesia providers decreased (adjusted absolute difference -4.1 total overtime hours per day; 95% CI -7.0 to -1.3; P=0.004). CONCLUSIONS: Implementation of a change in anaesthesia staffing model was associated with improved billing compliance, higher billable anaesthesia units, and reduced overtime. The effects of the anaesthesia staff model on revenue and financial margin can be determined using our web-based margin-cost estimation tool.
