[The efficacy of the benzodiazepine antagonist flumazenil (Ro 15-1788) based on the EEG of mechanically ventilated intensive care patients].

To evaluate the efficacy of flumazenil in intensive care medicine, the benzodiazepine antagonist was administered to 20 intubated and ventilated patients. In 18 cases the drug was used to interrupt long-term sedation (midazolam in combination with piritramide) for a short period of neurological examination. In two cases it was used to diagnose a coma of unknown origin. The patient's alertness was evaluated by clinical observation and electroencephalography. Blood pressure and heart rate were monitored continuously. The two patients with coma of unknown origin demonstrated no clinical response to flumazenil at a dosage of 2 mg. However, there was a change in the EEG: before administration of the antagonist, slow delta waves predominated; after administration there was an increase in theta activity. This activity shift was associated with a slight increase in the median frequency from 1.6 to 2.1 Hz. Serum level analysis confirmed a non-benzodiazepine-induced coma. The other 18 patients (average serum midazolam concentration: 0.27 microgram/ml) were awake and oriented after a dose of between 0.3 and 0.6 mg flumazenil. This clinical finding correlated with the EEG which showed an increase in the median frequency from 2 Hz to 6-7 Hz. Even after receiving the antagonist, the patients were able to tolerate intubation and ventilation without problem. No significant adverse effects were observed.