J Korean Neurosurg Soc.
1981 Sep;10(2):435-448.
Study on Local Cooling of the Brain in the Cat
- Affiliations
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- 1Department of Neurosurgery, College of Medicine, Korea University, Seoul, Korea.
Abstract
- With the purpose of avoiding the usual complications of systemic hypothermia and particularly those secondary to the lower tolerance of temperature of the cardiac neuromuscular elements as compared with tissue of the central nervous system, extravascular local cooling of the brain in cat was designed for the experiment. The experimental technique was deviced to cool the brain with cold liquid(2-3 degrees C) of physiological saline perfused or irrigated onto and with the salineice(-7 degrees C) rested on the surface of the brain. Thermocouples were introduced and placed at different depths of each 0.3cm in the brain, then the brain temperatures were measured at each depth before and during cooling every 10 minutes. Average temperature of brain surface before cooling was 35.7+/-1.7 degrees C and mean of it recorded from surface to 1.5cm depth in the brain was 36.7+/-1.1 degrees C in 20 cats. During cooling temperatures was effectively and markedly droped at extent of 0.6cm thick in the subcortical tissue, and at 20 minutes, cooling the maximal drop of temperature was recorded. During cooling with saline solution, average temperature of normal brain surface was 22.3+/-41 degrees C and mean of it recorded at different depths in brain was 28.7+/-2.5 degrees C. During cooling with saline ice, average temperature of normal brain surface was 12.2+/-2.6 degrees C, and mean of it recorded at different depths in brain was 22.0+/-1.3 degrees C. Temperature in the areas of brain injured by contusion or compression was relatively lower than in the normal brain. Temperature lowering in the injured brain during the cooling was more evident and marked in its degree than that in normal brain. Gross neurological examination failed to demonstrate any impairment of voluntary motor function after the cooling of brain for 50 minutes.