Evaluation of outcomes of robotic liver surgery using the IWATE criteria

Robotic liver resections (RLRs) are increasingly performed worldwide. The IWATE criteria offer a standardized classification to correlate the complexity of these procedures with surgical outcomes. This study analyzes a single surgeon's experience with RLR and evaluates the applicability and correlation of the IWATE criteria.

We conducted a retrospective analysis of 188 RLRs performed by a single surgeon at the University of Illinois at Chicago from June 2007 to May 2023. Data on patient demographics, surgical details, pathology, and 30-day morbidity and mortality were collected. Surgical data included operation duration, blood loss, conversion rates, intraoperative and perioperative complications, and length of hospital stay (LOS). Patients were categorized into four groups according to the IWATE criteria.

Patients were evenly distributed across the four groups, except for age and preoperative chemotherapy rates, which were significantly different. Operative times (OTs) and estimated blood loss (EBL) increased with procedure complexity, ranging from 148 to 350 minutes and 75 to 400 mL (P<0.001). There were 18 conversions (9.6%), with a significantly higher rate in the Expert and Advanced groups (P<0.001). Intraoperative transfusions followed the same pattern. Postoperative outcomes showed a significant difference in median hospital stay (P<0.001), varying from 3 to 7 days (Low to Expert groups). There were 8 major complications and a 3.7% readmission rate, with no 30-day mortality, and no significant difference in complication distribution among groups. The overall R0 resection rate was 96.3%.

The IWATE criteria effectively correlate with surgical outcomes in our series, providing a valuable tool for standardizing procedure complexity and facilitating outcome comparisons.