Applying classification of intraoperative adverse events (ClassIntra) to robot-assisted radical prostatectomy to predict the risk of postoperative adverse events

PURPOSE: To investigate intraoperative adverse events (IAEs) during robot-assisted radical prostatectomy using classification of intraoperative adverse events (ClassIntra) and their association with postoperative adverse events. PATIENTS AND METHODS: This was a retrospective population-based cohort identified from an approved common database (Dai-CAD) for robot-assisted radical prostatectomy for prostate cancer at 25 Japanese institutions between 2011 and 2023. IAEs were graded according to ClassIntra. The association between IAEs and postoperative adverse events was examined using multivariate logistic regression analysis. RESULT: Of the 8193 patients, 9 were excluded due to concurrent colon or rectal surgery concurrently (n = 6) and salvage surgery (n = 3), and the remaining 8184 patients were included in this study. Of the 8184 patients, 88 experienced ClassIntra grade ≥  2 IAEs. Among them, 50 patients (57%) experienced grade 2 IAEs, 32 (36%) experienced grade 3 IAEs, six patients (6.8%) experienced grade 4 IAEs, and no patients experienced grade 5 IAEs. Multivariate analysis revealed that ClassIntra grade   ≥   2 IAEs were independent risk factors for Clavien-Dindo grade ≥ 2 postoperative adverse events (odds ratio [OR] 2.62, 95% confidence interval [95%CI] 1.44-4.75, p = 0.002). Furthermore, ClassIntra grade   ≥  3 IAEs were independent risk factors for Clavien-Dindo grade  ≥  2 (OR 5.23, 95%CI 2.43-11.2, p < 0.001) or ≥ 3 postoperative adverse events (OR 4.92, 95%CI 1.49-16.3, p = 0.009). CONCLUSION: Evaluating IAEs according to ClassIntra is associated with postoperative adverse events and may support postoperative risk assessment according to the Clavien-Dindo classification.