Randomized Controlled Trial on the Effect of Intermittent Pedicle Clamping Using 15 or 30 Minutes Ischemic Intervals During Liver Surgery

Surgical procedure Patients were anaesthetized using isoflurane and propofol. They routinely had an epidural catheter, urinary catheter, two peripheral venous catheters and indwelling catheters in a jugular vein and radial artery. Body temperature was maintained using a Bair Hugger system (Arizant Healthcare Inc. Eden Prairie, Minnesota).

The surgical procedure was performed using a subcostal bilateral incision and Olivier retractors to improve exposure. After dissection of the teres hepatis ligament, the liver was mobilized. Thereafter, an intra-operative ultrasound was performed to define the position of the tumour in relation to vascular and biliary structures. As IPM was not routinely applied, a patient was randomized for 15 minted IPM (15IPM) or 30 minutes IPM (30IPM) only after the surgeon had decided a complete Pringle manoeuvre would be required. During 15IPM or 30IPM, the complete portal triad was clamped using a rubber sling. The time of inflow occlusion was adapted to the need according to the randomization protocol. Occasionally, the left or right pedicle was ligated after protocolled IPM. Five minutes reperfusion intervals were applied during which transection was stopped and cut surfaces were gently compressed to ensure hemostasis. A Cavitron Ultrasonic Surgical Aspirator (CUSA system 200 macrodissector, Cavitron Surgical Systems, Stamford, Connecticut) and Argon beam coagulation (Force GSU System, Valleylab, Boulder, Colorado) were used for liver transection. A stapler device or clamps were used for transection of the hepatic veins. Central venous pressure was maintained below 5 centimetre of water (cm H2O) during transection to reduce venous back-bleeding. After surgery, the weight of the resection specimen was recorded. Perioperative care was protocolled, as described earlier.