[Use of cortical SEP for the prediction of neurological prognosis after cardiopulmonary resuscitation].

The improved technique of cardiopulmonary resuscitation (CPR) resulted in survival of many patients who had experienced cardiopulmonary arrest (CPA). However, when the recovery of brain function is poor, patients suffer from severe neurological sequelae, including persistent vegetative state. There have been no conclusive methods to predict the outcome of anoxic encephalopathy after CPR. Madl et al (1993) recorded cortical SEP over the parietal scalp electrodes after bilateral median nerve stimulation at the wrists in anoxic patients experiencing CPR. Their results indicated that the median SEP is useful for the early prediction of neurological prognosis after CPR. We studied short and long latency cortical SEPs evoked by the left median nerve stimulation in 18 consecutive anoxic patients within 48 hours after CPR. The absence of N20, N35, P45 indicated mortality of 86.4% (100% in Madl's results). Preserved N60 peak indicated the recovery of consciousness, while Madl's results showed that patients did not regain consciousness when the N60 latency was longer than 121 ms. Neurological prognosis showed the significant correlation with N20, P25 amplitude and not with amplitude ratio (N20 P25/P15 N20). Reduced amplitude of N20 P25 was consistent with the high score of GOS. N20 P25 was greater than 3.7 microV in all patients who regained consciousness. Recording of cortical SEP within 48 hours after CPR was useful for the prediction of neurological outcome.