LAUSR

Purpose To evaluate the Comprehensive Complication Index (CCI) for reporting complications in lower urinary tract transurethral procedures and compare it to the Clavien Dindo classification (CDC). Methods 450 consecutive patients were included into the analyses (each 150 of Transurethral Resection of Bladder Tumours (TURBT), Transurethral Resection of the Prostate (TURP) and Transurethral Enucleation of the Prostate using Tm:YAG, (ThuLEP). Complications were assessed according to the modified CDC. The CCI was calculated using a freely accessible online tool. Descriptive statistics and correlation analyses have been applied to quantify operational differences and length of stay (LOS) between CDC and CCI. Sample size calculations for hypothetical clinical trials were contrasted for CDC and CCI application. Results Overall n=150 patients with complications (33.3%) within the first 60d after surgery were identified. Of these, n=125 (83.4%) were minor complications up to CDC grade IIIa. Of patients with complications, n=57 patients (12.6%) experienced more than one complication. Here, the cumulative CCI led to an upgrade of at least one CDC grade in 33 patients. Hence in 22.0% of cases, the highest CDC grade underestimated the degree of complications. CCI showed higher correlation with LOS compared to CDC (all r >0.2, all p-values ≤0.0001). Using CCI instead of CDC for sample calculation resulted in a strong reduction of the required number of patients for all 3 interventions (percentage of patient number decrease: -93.2% for TURBT, -71.8% for TURP and -81.1% for ThuLEP). Conclusion The CCI gives a more precise interpretation of the postinterventional complications of TURBT, TURP and ThuLEP. CCI application may reduce the required sample size for clinical trials and will relieve their recruitment in the future.