The effects of amrinone and calcium chloride on pulmonary vasculature and biventricular function in ethchlorvynol-induced lung injury in sheep.

Abstract

The effects of amrinone and CaCl2 on pulmonary vasculature and biventricular function in sheep with acute lung injury (ALI) were studied. Seven sheep were ventilated with a tidal volume of 10-12 ml.kg-1 with end-tidal CO2 of 40 +/- 5 mmHg (5.3 +/- 0.7 kPa) after acute lung injury was induced with up to 30 mg kg-1 of ethchlorvynol (ECV). Biventricular function and hemodynamic profiles were estimated with a rapid computerized thermodilution method and modified pulmonary artery catheters after acute lung injury, following a loading dose (1 mg kg-1) and maintenance dose (5 micrograms kg-1 min-1) of amrinone and after a bolus dose of CaCl2 (20 mg kg-1). ECV successfully induced acute lung damage in sheep, causing significant increases in pulmonary artery pressure (PAP) and pulmonary vascular resistance index (PVRI). Amrinone reversed the unfavorable changes induced by ECV, significantly reducing PAP, PVRI and left ventricular end-diastolic volume (LVEDV). CaCl2, however, reversed the effect of amrinone and increased PAP, PVRI, and LVEDV but decreased left ventricular ejection fraction.