Establishment of Deep Hypothermic Circulatory Arrest in Rats

Deep hypothermic circulatory arrest (DHCA) is routinely applied during surgeries for complex congenital heart disease and aortic arch disease. The present study aims to provide a method for establishing DHCA in rats. To evaluate the impact of the DHCA process on vital signs, a normal temperature cardiopulmonary bypass (CPB) rat model without circulatory arrest was used as a control. As expected, DHCA led to a significant decrease in body temperature and mean arterial blood pressure. The blood gas analysis indicated that DHCA increased lactic acid levels but did not influence the blood pH and the concentrations of hemoglobin, hematocrit, Na⁺, Cl^-, K⁺, and glucose. Furthermore, compared with the normal temperature CPB rats, the results of the transmission electron microscopy showed a mild increase in hippocampal autophagosomes in the DHCA rats.