Effects of artificial circulation by pulsatile and non-pulsatile flow on brain tissues

We examined the effects of artificial circulation by pulsatile and non-pulsatile flow on microcirculation in the brain from the viewpoints of circulation and metabolism in the brain. A centrifugal pump was fixed in the bypass in the right heart of 10 pigs. In 5 of the 10 pigs, a pulsatile flow pump was fixed in the bypass in the left heart (P group), and in the remaining 5 pigs, a centrifugal pump was fixed in the bypass in the left heart (NP group). Hemodynamics were periodically monitored for 3 hours while maintaining about 100 mmHg of the mean aortic pressure. Intracranial pressure (ICP), cerebral tissue blood flow and cerebral blood flow (CBF) were measured and compared with the initial values. As the parameters of metabolism in the brain, the cerebral oxygen consumption and lactic acid - pyruvic acid ratio were evaluated. If the cerebral blood flow was reduced by cardiogenetic shock, we suggest that blood circulation and metabolism in the brain were maintained by artificial circulation. It also indicated that there was no significant difference in blood circulation and metabolism in the brain between artificial pulsatile and non-pulsatile flow circulation.