COMPUTER-AIDED ANALYSIS OF HEART-RATE-VARIABILITY IN BRAIN-DEATH

Forty neurosurgical, artificially ventilated patients were examined. T wenty of them had been diagnosed as brain dead, while twenty non-brain -dead patients served as a control group. From a surface ECG taken ove r a period of live minutes the mean heart rate and various indices of heart rate variability (HRV) were determined with the help of a specia l computer program (ProSciCard, Medisyst, Germany). The heart rate of the brain dead was significantly higher than that of the control patie nts. By contrast, all parameters of HRV were drastically reduced in th e brain dead individuals compared to the controls. The results show th at a significant change in the course of heart rate occurs after manif estation of brain death. This would appear to be the result of the eli mination of all vegetative impulses derived from the brainstem. Comput er-aided, the changes can be quantified in a simple way. The method co uld therefore be useful in brain death diagnosis.