Evoked potentials and the effect of flumazenil in patients with liver cirrhosis.

The presence of increased amount of ligands for benzodiazepine receptors has been demonstrated in cirrhotic patients. Evoked potentials (EP) recordings are a simple, suitable, and objective method for comprehensive evaluation of hepatic encephalopathy (HE). We evaluated the visual EP, brain stem auditory EP, and somatosensory EP (SSEP) and the effect of benzodiazepine receptor antagonist flumazenil in patients with liver cirrhosis. EP of 38 patients with liver cirrhosis were recorded on the electrodiagnostic system Neuropack 8 (JB-441 B, Nihon Kohden). Eleven patients (nine males and two females; mean age 60 years; six with stage 0,4 with stage one, and one with stage 2 HE) showed impairment in SSEP N13-N19 interval. After baseline period, boluses of 1 mg, 2 mg, and 3 mg flumazenil were injected every thirty minutes and SSEP recordings were repeated after every dosage. We did not find any difference before and after flumazenil in SSEP N13-N19 interval (7.3 +/- 0.4, 7.1 +/- 0.5, 7.1 +/- 0.4, and 7.1 +/- 0.6 minutes, respectively) (p < 0.05). But four patients (36%) showed a clear SSEP improvement with flumazenil. Our results suggest that in a subset of cirrhotic patients, flumazenil may have a role.