Creatine kinase elevation after robotic surgery for rectal cancer due to a prolonged lithotomy position

BACKGROUND: Robotic surgery for rectal cancer, which is now performed worldwide, can be associated with elevated creatine kinase levels postoperatively. In this study, we compared postoperative complications between patients undergoing robotic surgery and laparoscopic surgery. METHODS: We identified 66 consecutive patients who underwent curative resection for rectal cancer at Juntendo University Hospital between January 2016 and February 2019. Patients were divided into a conventional laparoscopic surgery (CLS) group (n = 38) and a robotic-assisted laparoscopic surgery (RALS) group (n = 28) before comparing various clinicodemographic factors between the groups. RESULTS: Patient age and gender, surgical approach (CLS/RALS), pathological T factor, pathological stage, duration of postoperative hospital stay, and postoperative complications were not significantly different between the RALS and CLS groups. However, the operation time was significantly longer in the RALS group (407 min) than in the CLS group (295 min; p < 0.001). Notably, the serum level of creatine kinase on postoperative day 1 was significantly higher in the CLS group (154 IU/L) than in the RALS group (525 IU/L; p < 0.001), despite there being no significant differences in the incidence of rhabdomyolysis. The multivariate analysis showed that RALS/CLS (HR 6.0 95% CI 1.3–27.5, p = 0.02) and operation time (HR 15.9 95% CI 3.79–67.4, p = 0.001) remained independent factors of CK elevation on postoperative day 1. CONCLUSIONS: Clinically relevant positioning injuries and rhabdomyolysis may occur in patients who are subjected to a prolonged and extreme Trendelenburg position or who have extra force applied to the abdominal wall because of remote center displacement. The creatine kinase value should therefore be measured after RALS to monitor for the sequelae of these potential positioning injuries.