Financial Impact of Unplanned Readmission Following Surgical Treatment of Chronic Subdural Hematoma and Its Implications for Interventional Adjuncts

OBJECTIVE: Chronic subdural hematoma (cSDH) is an increasingly prevalent neurosurgical condition. Unplanned readmissions following surgical evacuation represent a significant clinical and economic challenge. This study aims to identify predictors of 30-day readmission, evaluate their financial impact within the German Diagnosis-Related Group system, and determine the economic viability of adjunctive middle meningeal artery embolization (MMAE). METHODS: A monocentric retrospective analysis was conducted on 570 adult patients surgically treated for cSDH at a tertiary neurosurgical center between 2013 and 2023. Multivariable regression models were used to identify predictors of readmission and associated costs. To evaluate cost-effectiveness, a reverse threshold analysis was applied to calculate the maximum justifiable procedural cost for universal prophylactic MMAE to achieve cost-neutrality. RESULTS: The overall 30-day unplanned readmission rate was 16% (overall reoperation rate: 10%), with cSDH recurrence (specific recurrence rate: 8%), seizures, and surgical site infections identified as primary etiologies. Predictors for readmission included male sex (odds ratio, 1.94) and cardiovascular devices (odds ratio, 2.16). The mean financial burden per unplanned readmission was EUR 16,700. The threshold analysis revealed that, based on our 8% baseline recurrence rate and a mean cost difference of EUR 5800 for treating a recurrence, the break-even cost for adjunctive MMAE is merely EUR 4500 per procedure. CONCLUSIONS: While unplanned readmissions after cSDH surgery incur substantial financial burdens, universal prophylactic MMAE is currently not economically viable in standard populations based solely on institutional cost-savings. These economic metrics support a risk-adapted strategy, reserving interventional adjuncts for patients at a high clinical risk of recurrence.