The Comprehensive Complication Index for Advanced Monitoring of Complications Following Endoscopic Surgery of the Lower Urinary Tract.

To evaluate the Comprehensive Complication Index (CCI) for reporting complications in lower urinary tract transurethral procedures and compare it with the Clavien-Dindo classification (CDC). A total of 450 consecutive patients were included into the analyses [150 each of transurethral resection of bladder tumors (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 were 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. Overall  = 150 patients with complications (33.3%) within the first 60 days after operation were identified. Of these,  = 125 (83.4%) were minor complications up to CDC grade IIIa. Of patients with complications,  = 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 with CDC (all  > 0.2, all -values ≤0.0001). Using CCI instead of CDC for sample calculation resulted in a strong reduction of the required number of patients for all three interventions (percentage of patient number decrease: -93.2% for TURBT, -71.8% for TURP, and -81.1% for ThuLEP). 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.