Experimental Study Of Deep Hypothermic Circulatory Arrest In Brain Protection Solution

OBJECTIVE: With the development of the technique of cardiovascular surgery, the problem of cerebral protection is becoming more and more important. At present the method of cerebral protection common used such as deep hypothermic circulatory arrest(DHCA), DHCA selective cerebral perfusion (DHCA-SCP), DHCA retrograde cerebral perfusion (DHCA-RCP) has its own disadvantage respectively. The purpose of the present study was to provide an optimal method of cerebral protection for the clinical application. METHOD: Ten mongrel dogs were divided into two groups, which were placed on CPB via the ascending aorta and right atrium, cooled to a nasopharyngeal temperature of 18°C and submitted 120 minutes of total circulatory arrest. 5 dogs in the control group did not receive cerebralplegia and 5 dogs in the experimental group received oxygenated cerebralplegic infusion through the bilateral common carotid arteries. The dosage of the cerebralplegic infusion was 25ml/kg bodyweight at the onset of arrest, followed by 12.5ml/kg at 30-minute intervals during the arrest period. All animals were re-established the CPB and rewanned after 120 minutes of circulatory arrest. Cerebral cortex was collected to study adnosine triphosphate(ATP), malondialdehyde(MDA), thromboxane B₂(TXB₂), 6-Keto-PGF_1α, nitric oxide synthase(NOS) and ultrastructure at the time point of pre-CPB, 120 minutes of circulatory arrest and at 45 minutes of reperfusion in all animals. RESULTS: The level of ATP in the experimental group is higher significantly than that in the control group at 120 minutes of circulatory...