The effects of a hemoglobin-based oxygen carrier (HBOC-301) on left ventricular systolic function in anesthetized dogs

Objective-To evaluate the effects of a hemoglobin-based oxygen carrier (HBO C-301) on left ventricular preload, afterload, contractility, and ventricul o-arterial coupling in anesthetized dogs. Study Design-A prospective experimental study. Animals-Seven adult male dogs weighing 2.3 to 2.7 kg. Methods-The study was performed on intact, closed-chest, chloralose-anesthe tized dogs. Heart rate, left ventricular end-systolic and end-diastolic vol ume and pressure, cardiac output, stroke volume, blood resistivity, mean ar terial pressure (MAP), dP/dt(max) end-systolic elastance (E-es), systemic v ascular resistance (SVR), effective arterial elastance (E-a), left ventricu lar-arterial coupling (E-es/E-a), and myocardial oxygen consumption (MVo(2) ) were determined during a 90-minute infusion of 30 mL/kg (20 mL/kg/h) of H BOC-301 and for 90 minutes thereafter. Results-The administration of HBOC-301 significantly decreased packed cell volume, blood resistivity, heart rate, cardiac output, and dP/dt(max) and s ignificantly increased left ventricular end-diastolic and end-systolic pres sure, MAP, and SVR. The E-a, E-es, E-es/E-a, and MVo(2) did not change. Conclusions-HBOC-301 produced insignificant changes in load independent ind exes of cardiac performance (E-es, E-a, E-es/E-a) in anesthetized dogs. The collective directional changes in these variables, however, in conjunction with significant increases in SVR were most likely responsible for a decre ase in cardiac output. Increases in SVR and the volume load (30 mL/kg) cont ributed to increases in left ventricular end-diastolic pressure. Clinical Relevance-HBOC-301 infusion should be monitored and administered c autiously to dogs with poor ventricular function. (C) Copyright 2000 by The American College of Veterinary Surgeons.