Bedside Assistant Suction Response and Visual Field Recovery During Robot-Assisted Rectal Cancer Surgery: An Exploratory Propensity Score-Matched Comparison of Assistant-Access Workflows Using Hinotori and da Vinci Xi.

INTRODUCTION: Timely suction is essential when bleeding or oozing obscures the operative field during robot-assisted rectal cancer surgery; assistant-access workflow may influence the response. METHODS: This exploratory, retrospective, matched cohort study compared a hinotori workflow with an additional assistant port and a conventional da Vinci Xi port configuration. Eleven hinotori and 82 da Vinci Xi cases were eligible. Propensity score matching was performed using body mass index, preoperative treatment, and tumor location; 10 matched pairs had analyzable videos. Visual field disturbance was defined as bleeding or oozing obscuring the operative view and requiring suction. The times from event onset to suction initiation and from onset to a restored view were defined as latency and time to recovery, respectively. Event-level outcomes were log-transformed; effect sizes were mean log differences and geometric mean ratios. Wilcoxon signed-rank tests using case-level medians were used for sensitivity analyses. RESULTS: Overall, 152 events were identified (64 hinotori, 88 da Vinci Xi). The hinotori workflow was associated with shorter latency (mean log difference, -0.633; 95% confidence interval [CI], -1.021 to -0.244; p = 0.001; geometric mean ratio, 0.531; 95% CI, 0.360-0.783) and shorter time to recovery (mean log difference, -0.438; 95% CI, -0.739 to -0.137; p = 0.004; geometric mean ratio, 0.645; 95% CI, 0.478-0.872). Sensitivity analyses yielded consistent results. CONCLUSION: A hinotori-specific assistant-port workflow was associated with faster suction response and visualization recovery. These exploratory findings require cautious interpretation because of institutional and assistant-related confounding.