A comparison of blood and Fluosol-DA for cardiopulmonary bypass

Fluosol-DA was compared to blood as a pump prime for total cardiopulmonary bypass in the pig animal model. Nineteen pigs weighing between 14 and 22 kg were studied, nine with blood and ten with Fluosol. Metabolic and hemodynamic measurements were determined before, during and after 60 minute bypass to establish the adequacy of Fluosol to sustain perfusion as compared to blood. The measurements and subsequent calculations included blood gases, arterial and mixed venous oxygen content, oxygen extraction and consumption, cardiac output, systemic and pulmonary vascular resistance and arterial, venous, pulmonary artery and left atrial pressures. The result showed a significant decrease in hematocrit during bypass in the Fluosol group as compared to blood perfusion (20 vs. 30%). While the arterial oxygen content fell from control levels with Fluosol during bypass, in the blood prime group, oxygen content remained at pre-control levels. Whole body oxygen consumption decreased during bypass, in both groups equally, but this decrease did not lead to acidosis and was stable during recovery. Oxygen and carbon dioxide transport were adequately maintained during bypass in both Fluosol and blood groups. Systemic pressures remained stable during bypass and were lower, but stable, during recovery. Pulmonary vascular resistance was elevated in both groups during recovery which probably explains a concomitantly decreased cardiac output. There was a 40% mortality in both experimental groups secondary to postpump pulmonary hypertension. It is concluded that Fluosol is a satisfactory oxygen carrying agent to be used instead of blood during cardiopulmonary bypass, and in the pig model both blood and Fluosol were associated with a high incidence of pulmonary hypertension.