浸泡性体温过低对犬心功能的影响

目的 探讨浸泡性低温过低对犬心功能的影响.方法 4只健康杂种犬置于(6±1)℃的冷水中全身浸泡致发生室颤.用多道生理记录仪测定犬心功能指标,心电图仪测定心电图,透射电镜观察室颤犬心肌组织变化.结果 随着动物体温下降,犬左心室内压值(LVSP)、左心室内压最大上升/下降速率(±dp/dtmax)明显下降,Q-T间期延长,可见低温性J波,出现室颤.结论 体温过低可导致心功能下降,Q-T间期延长和低温J波的出现预示室颤发生.

Abstract：

Objective To investigate the effect of cold water immersion on the cardiac function of dogs. Methods Four healthy dogs were immersed in cold water at ( 6 ± 1 ) ℃ until the onset of ventricular fibrillation. Electrocardiogram was recorded with Cardiofax, cardiac function was monitored with the polygraph system, and changes in the structure of myocardium were observed with the transmission electron microscope.Results With the decrease in the body temperature of animals, marked changes in the decrease of the left ventricular pressure peak value (LVSP) and isovolumetric contraction of maximal ascending/descending velocity ( ± dp/dtmax) could be noted. When high -grade hypothermia occurred, J wave was found with a prolonged Q-T duration, and subsequently, there came the rapid ventricular arrhythmia. Conclusions Hypothermia could induce the decrease in the canine cardiac function, moreover, the prolongation of Q-T and the appearance of J wave might predict the occurrence of ventricular fibrillation.

Effect of hypothermia induced by cold water immersion on the cardiac function of dogs

Objective To investigate the effect of cold water immersion on the cardiac function of dogs. Methods Four healthy dogs were immersed in cold water at ( 6 ± 1 ) ℃ until the onset of ventricular fibrillation. Electrocardiogram was recorded with Cardiofax, cardiac function was monitored with the polygraph system, and changes in the structure of myocardium were observed with the transmission electron microscope.Results With the decrease in the body temperature of animals, marked changes in the decrease of the left ventricular pressure peak value (LVSP) and isovolumetric contraction of maximal ascending/descending velocity ( ± dp/dtmax) could be noted. When high -grade hypothermia occurred, J wave was found with a prolonged Q-T duration, and subsequently, there came the rapid ventricular arrhythmia. Conclusions Hypothermia could induce the decrease in the canine cardiac function, moreover, the prolongation of Q-T and the appearance of J wave might predict the occurrence of ventricular fibrillation.