Introduction: Bundled payments are value-based reimbursement models that link payments to providers for episodes of care related to inpatient admissions for certain conditions. What remains a limitation of episode-based payments, however, is their inability to account for health care expenditures that may accrue prior to the inciting inpatient admission. Renal colic is uniquely suited to evaluate the association between pre- and post-operative events. Renal colic episodes often begin in the emergency department and may require both inpatient and ambulatory care prior to definitive surgery. Therefore, limiting bundles to inpatient admissions associated with surgery may miss important upstream events that influence post-operative outcomes. The objective of this study is to better understand how pre-operative costs may relate to operative and post-operative costs for a renal colic episode. Methods: Using 2018 data from the Healthcare Cost and Utilization Project, we identified individuals in Maryland and Florida who had a renal colic diagnosis, a subsequent definitive surgical episode after diagnosis, and a post-surgical health care encounter within 90 days of surgery. We then limited our sample to individuals who had information about pre-operative, operative, and post-operative costs. We categorized individuals into quartiles based on incurred costs during the pre-operative, operative, and post-operative periods. We then plotted the number of individuals in each quartile across the care time horizon using a Sankey diagram to visualize costs throughout a renal colic episode. Results: A total of 1,525 individuals in Florida and Maryland underwent definitive surgery for renal colic during the study period. When looking at the movement of individuals between pre-operative and operative quartiles, 207 of 381 individuals (54.3%) with the lowest pre-operative costs remained in either the 1st or 2nd quartile of operative costs. Meanwhile, 219 out of 381 individuals (57.3%) in the highest quartile had operative costs in the upper half. Similar results are seen when looking at movement of individuals between operative and post-operative quartiles. Most of the individuals in the lowest quartile of operative costs remained in the lowest quartile of post-operative costs while individuals in the highest quartile of operative costs remained in the top two quartiles of post-operative costs. Conclusions: Our findings suggest that pre-operative spending influences post-operative expenditures for an episode of renal colic, and accounting for this relationship may help inform future iterations of surgical payment bundles. SOURCE OF Funding: American Urological Association Research Scholars Grant
