RECOVERY OF RAT'S HEART AND RESPIRATION FUNCTIONING DURING EMERGENCE FROM DEEP HYPOTHERMIA IN THE PROCESS OF SELF-HEATING AND WITH AN EXTERNAL HEATER
The article presents modeling of the organism emergence from hypothermia preceded by cardiac arrest. Experiments were performed with anaesthetized Wistar male rats and monitoring the breathing rate, heart rate, blood pressure, arterial oxygen saturation, rectal and esophagal temperature. Rats were kept immersed in water at 8–10 °С till the respiratory arrest and cardiac activity reduction. In 5 minutes, artificial ventilation was administered to restore a normal cardiac rhythm and rate. In one model, the rats had to warm themselves after withdrawal from water. In the other, the rats were held in water till arrest of the previously activated heart. Afterwards the rat's chest wall was heated to restore the cardiac activity. Artificial ventilation was stopped when animal showed signs of breathing. According to the results, in the second model anoxia together with a deeper cooling slowed down recovery of the cardiac and breathing functions. These experimental models can be used for verification of procedures of emergence from deep hypothermia and testing resuscitation pharmaceuticals.