[Hemodynamic and metabolic changes during orthotopic liver transplantation]

Hemodynamic and metabolic profiles were obtained on 48 adult patients (mean age 46 years) undergoing orthotopic liver transplantation without using a bypass technique during the anhepatic period. Baseline measurements after induction of anesthesia (A) revealed a high-output circulatory state. During hepatic dissection (B, preclamping control), mean arterial pressure (MAP), mean pulmonary artery pressure (MPAP), pulmonary capillary wedge pressure (PCWP), right atrial pressure (RAP), and elevated cardiac index (CI) were well maintained. Preoperative plasma exchange with fresh frozen plasma in the presence of severe coagulation defects and liberal use of platelet concentrates limited the need for massive blood transfusion, and thus contributed to stable hemodynamics during this stage. Significant cardiovascular changes occurred immediately after clamping of the inferior vena cava and the portal vein (C): there was a marked fall in MAP (-30%), MPAP (-45%), PCWP (-48%), RAP (-40%), and CI (-60%) reflecting the hemodynamic adaptation to the impeded venous return. At the end of the anhepatic period (D), MAP (-21%), MPAP (-38%), PCWP (-39%), RAP (-24%), and CI (-56%) were persistently lowered because no attempts were made to attenuate the clamping response by vigorous volume expansion or infusion of inotropic drugs. The reduction in oxygen availability index (O2AVI) was compensated by enhanced oxygen extraction. Oxygen consumption index (VO2I) fell secondary to the removal of the liver and the decrease in body temperature (BT). Potassium levels and acid-base balance were well controlled; no hypoglycemic episode was observed during the anhepatic period.(ABSTRACT TRUNCATED AT 250 WORDS)