Background and purpose: During robot-assisted radical prostatectomy (RARP), patients remain in a steep Trendelenburg position. This can cause positioning injuries as well as rhabdomyolysis. The primary diagnostic indicator of rhabdomyolysis is elevated serum creatine kinase (CK). We investigate whether RARP with extended pelvic lymph node dissection (ePLND) in a prolonged extreme Trendelenburg position can cause positioning injuries and rhabdomyolysis.
Patients and methods: We performed a prospective study of the first 60 patients undergoing RARP and ePLND for organ-confined prostate cancer at our institute. Positioning injuries were graded according to three degrees of clinical severity. Serum-CK, serum-pH, and base excess (BE) were measured before, during, and for 5 days after surgery. Rhabdomyolysis was defined by serum-CK levels >5000 IU/L.
Results: Median operative time was 317 minutes (range 200-475 min); median time in the Trendelenburg position was 282 minutes (range 170-470 min). Serum-CK was significantly elevated 6 hours postoperatively, peaking at 18 hours postoperatively. Serum-CK levels did not correlate with pH, BE, and perioperative creatinine values. Serum-CK course shows weak correlation with body mass index (BMI), operative time, Trendelenburg position time, and medium correlation with positioning injuries of any degree. Twenty-one of the 60 (35%) patients showed positioning-related injuries: 16 (27%) patients degree I, 2 (3%) patients degree II, and 3 (5%) patients degree III. Rhabdomyolysis developed in 10 patients. Postoperative renal failure did not develop in any patient receiving postoperative hypervolemic diuretic therapy nor any patient with injuries degrees I, II, or III. conclusion: Clinically relevant positioning injuries and rhabdomyolysis can occur in patients who are subjected to prolonged extreme Trendelenburg position during RARP and ePLND, especially at the beginning of the learning curve. Serum-CK increases significantly after surgery, peaking 18 hours postoperatively. Serum-CK elevation alone is not predictive of positioning injury. By very long operative and Trendelenburg times as well as high BMI with visible position injuries, we recommend serum-CK measurement 6 and 18 hours postoperatively followed by hypervolemic therapy to prevent possible renal injury from rhabdomyolysis if serum-CK >5000 IU/L.