重症脑损伤低体温与心率变异的相关性

Relationship between hypothermia and heart rate variation in severe brain injury

AIM:To investigate effects of heart automatic nerve variations and hypothermia(HT) therapy on heart rate variation(HRV).METHODS:We studied the dynamic electrocardiagraph (ECG) of 41 cases of severe brain injury.The patients were devided into HT therapy group(n=21, body temprature 32- 33 ℃ ),non HT therapy group(n=20) and normal control(n=20).RESULTS:In group 1, the reduction of time domain indexes and frequency domain indexes were 3- 6 folds and 30- 50 folds respectively compared with those of the control group, while the corresponding indexes reduction were 2- 3 folds and 4- 5 folds in the group 2(P< 0.05,P< 0.01,respectively).The difference between groups were significant(P< 0.05- 0.01);the HRV reduction was more significant in the cerebrovascular accident patients than that of brain injured(P< 0.05- 0.01);the HRV indexes increased significantly in resuscitated patients than those in coma(P< 0.01); the HRV in dead was much lower than that in survival(P=0.01).CONCLUSION:Injury of central nervous system can induce abnormal function of automatic nerve of heart and reduction of HRV.HT therapy can reduce HRV on a higher level;HRV examination can be applied into the prediction of prognosis of the brain injured.