Effect of blood flow rate on thrombogenesis in a rabbit extracorporeal circulation model

Blood flow is believed to affect the thrombogenicity of extracorporeal circulation (ECC). The purpose of this study was to look at the relationship between blood flow and thrombogenicity in a rabbit model of ECC. Rabbits were anesthetized and systematically heparinized. Bilateral jugular cannulation was performed, and the animals were placed on venovenous ECC. The circuits were composed of 1 m of 1/4 inch size surgical grade polyvinylchloride (PVC) tubing. ECC was maintained for 4 hours. Three experimental groups were studied: a high flow group (n=7; flow rate: 30 ml/min/Kg), low flow group (n=7; flow rate: 10 ml/mg/Kg), and no ECC group (n=7). Platelet count, fibrinogen concentration, PaO2/FiO2, and postmortem findings were evaluated. Platelet consumption was higher with high flow, and fibrinogen consumption was higher with low flow.