The effects of intraoperative intravenous clonidine on fluid requirements, hemodynamic variables, and support during liver transplantation: a prospective, randomized study.

In this prospective, nonblind study, we report the use of clonidine during orthotopic liver transplantation (OLT). Twenty adult patients in a stable medical condition were studied. General anesthesia consisted of isoflurane in air/oxygen and sufentanil. Patients in the clonidine group received a slow i.v. infusion (15 min) of 4 microg/kg clonidine during induction. The other patients were used as controls. I.v. fluid requirements were determined as follows: albumin (4% solution) was administered to maintain filling pressures to a pulmonary capillary wedge pressure (PCWP) of more than 12 mm Hg. Packed red blood cells were transfused to maintain a hemoglobin level of 8-9 g/dL. Circulatory stability was evaluated using: systolic and diastolic arterial blood pressure and heart rate recorded at 2-min intervals; and the vasopressor/inotropic support required to maintain adequate hemodynamic variables after reperfusion. Intraoperative albumin and packed red blood cell requirements were significantly reduced in patients in the clonidine group (1644 +/- 140 and 50 +/- 50 mL vs 2867 +/- 226 mL and 1350 +/- 443 mL; P < 0.05). Heart rate was significantly slower in patients of the clonidine group. There were no differences in systolic arterial blood pressure. After reperfusion, patients in the control group showed significantly lower diastolic arterial blood pressure, required more vasopressor/inotropic support, and were more acidotic than patients in the clonidine group. We conclude that the administration of 4 microg/kg clonidine during induction of OLT significantly reduced the intraoperative requirements of i.v. fluids and blood products without compromising circulatory stability. Improvement in immediate reperfusion-induced disturbances was observed. IMPLICATIONS: The administration of 4 microg/kg clonidine during induction of liver transplantation significantly reduced the intraoperative requirements for i.v. fluids and blood products without compromising the circulatory stability. Improvement in immediate reperfusion-induced disturbances was also observed.