Minimising warm ischaemia time during robot-assisted partial nephrectomy. A video-based assessment of tumour excision, kidney reconstruction and intermediate time.

Introduction: Surgical video review is an emerging tool for assessing patient outcomes, especially in complex surgeries such as robot-assisted partial nephrectomy (RAPN). Assessing and measuring warm ischaemia time (WIT) during RAPN by dividing it into the time used for tumour excision time (ExcT), time used for kidney reconstruction time (RecT) and intermediate time (IntT) has not been performed before. This study aimed to analyse the factors that can influence all surgical times and assess their impact on positive surgical margins (PSMs) and complication rates.

Methods: We evaluated 32 surgical video recordings from patients undergoing RAPN and measured WIT, ExcT, RecT and IntT with a stopwatch. Factors such as tumour characteristics and surgeon experience were also recorded. SPSS software was used to identify the predictors for all surgical times and to correlate ExcT with PSM and RecT with complication rate.

Results: We recorded a median WIT of 1,048 s (17 min and 28 s). The median of ExcT, RecT and IntT was 398 s (37.1% of WIT), 518 s (46.7% of WIT) and 180 s (16.2% of WIT), respectively. We found a significant correlation (P < 0.001) between R.E.N.A.L. score and all surgical times. No correlation was found between ExcT and PSM (P = 0.488) and between RecT and the probability of developing complications (P = 0.544).

Conclusion: Tumour morphology influences all surgical times, and surgeon experience influences only ExcT. We observed a short RecT during RAPN though at the cost of increased ExcT, and we believe that improving surgical experience, especially for the excision of more complex tumours, can reduce WIT during RAPN.