Robotic CME in obese patients: advantage of robotic ultrasound scan for vascular dissection

Complete mesocolic excision (CME) in right-sided colon cancers appears to confer oncological benefits compared to conventional colectomy. Identification of the superior mesenteric vein (SMV) remains challenging. We describe the novel use of intra-operative robotic ultrasound scan (rUSS) in obese patients (BMI ≥ 29). All consecutive patients having robotic CME for colon cancer between 2014 and 2017 were included in this retrospective cohort study. Data were recorded on an ethics approved prospective database and included patient demographics, clinical and oncological outcomes. Patients were divided into group 1 (BMI ≤ 28) and group 2 (BMI ≥ 29). SMV first approach was employed in all cases and SMV detection was aided using rUSS in group 2. Primary outcome was postoperative morbidity. Secondary outcomes included conversion rate, operative time and length of stay (LOS). 41 (group 1, median 66 years) were compared to 32 patients (group 2, median 63 years). There were no conversions to laparoscopy or laparotomy. Median operative times for group 2 were 30 min longer (186 vs. 216 min, p = 0.05). Overall morbidity was similar (20% vs. 19% in group 1 and 2, p = 0.26). There was no significant difference between the two groups with regard to LOS (median 7 vs. 6 days, p = 0.48), readmissions (2 vs. 5, p = 0.13), R0 resection rate (98% vs. 94%, p = 0.43) and lymph node harvest (median 31 vs. 30, p = 0.28).CME can be technically more challenging than conventional colectomy in obese patients and is associated with longer operative times. The use of rUSS in obese patients can help to identify SMV and allow safer dissection.