Intraoperative management of a patient undergoing extracorporeal liver surgery (bench surgery)

Effect of anhepatic phase of surgery using veno-venous bypass technique on plasma fentanyl concentration. Report of two cases

We administered fentanyl continuously and measured its concentration in plasma in two patients undergoing surgery which produced an anhepatic phase using the veno-venous bypass technique; one patient had extracorporal liver resection and the other had venoplasty of the inferior vena cava and the right hepatic vein. The plasma fentanyl concentration increased during the anhepatic phase and decreased in the post-anhepatic phase in both cases. Though fentanyl has a wide safety margin, attention must be paid to such drug characteristics in the management of anaesthesia during the anhepatic phase.