Objective: American Society of Anesthesiologists-Physical Status scores (ASA-PS) and age were used to adjust for case-mix differences when evaluating surgical morbidity and resource use after total hip replacement (THR), transurethral prostatectomy (TURP), or cholecystectomy.
Summary background data: Variations in complication rates or resource use among patients treated for a particular primary condition should be adjusted for coexistent disease. Age and ASA-PS scores are readily available and can be useful to stratify surgical patients for risk.
Methods: One thousand ninety patients at five academic medical centers in California and Massachusetts who underwent THR, TURP, or cholecystectomy between 1985 and 1987 were studied. Data were obtained from medical records and a self-administered questionnaire to measure length of stay (LOS), postoperative complication rates, and follow-up physician visits. Data were analyzed with one- and two-way analysis of variance with the Bonferroni correction.
Results: Increasing age and ASA-PS scores were associated significantly with increased LOS, complication rates, and frequency of post-discharge physician office visits. No interaction effect between age and ASA-PS scores was observed.
Conclusions: Age and ASA-PS scores can predict postoperative morbidity, specific for each operation studied. Assessment of co-morbidity in surgical patients can be accomplished easily and with minimal expense. While remaining budget neutral, the distribution of reimbursements should be based on those preoperative risk factors that predict longer LOS and higher complication rates.