Quality assessment in high-acuity surgery: volume and mortality are not enough.

HYPOTHESIS A new quality assessment model for high-acuity surgery links process improvements with hospital costs and patient-centered outcomes and accurately reflects the clinical and economic impact of variance in patient acuity at the level of the practice and health care professional. DESIGN Retrospective case series and cost analysis. SETTING University tertiary care referral center. PATIENTS A total of 296 patients undergoing elective pancreatic resection in 5 years. MAIN OUTCOME MEASURES Expected preoperative morbidity (evaluated using POSSUM [Physiologic and Operative Severity Score for the Enumeration of Mortality and Morbidity]) was compared with observed morbidity (according to the Clavien complication scheme) and was correlated with total hospital costs per patient. RESULTS As volume increased annually, patient acuity (expected morbidity) rose and complications declined. Overall, observed and expected morbidity rates were equal (54.1% vs 55.1%), for an observed-expected ratio of 0.98. Process improvement measures contributed to a steady decrease in the observed-expected morbidity ratio from 1.34 to 0.81 during the 5-year period. This decrease was strongly associated with significant cost savings as total costs per patient declined annually (from $31 541 to $18 829). This performance assessment model predicts that a 0.10 decrease in the observed-expected morbidity ratio equates to a $2549 cost savings per patient in our practice. CONCLUSIONS Despite increasing patient acuity, better clinical and economic outcomes were achieved across time. Approaches that mitigate the impact of preoperative risk can effectively deliver quality improvement, as illustrated by a reduced observed-expected morbidity ratio. This approach is valuable in analyzing performance and process improvements and can be used to assess intrapractice and interpractice variations in high-acuity surgery.