[Lidocaine elimination and MEGX formation after oral lidocaine administration--a practicable test for assessment of quantitative liver function]. / Lidocainelimination und MEGX-Bildung nach oraler Lidocainbelastung--Ein praktikabler Test zur Abschätzung der quantitativen Leberfunktion.

Oral load with 200 mg Lidocain was performed in 370 patients with chronic liver disease. The 120- and 240-minute Lidocain plasma concentrations as well as the 30- and 60-minute MEGX plasma concentrations, main metabolite of Lidocain, were measured by means of gas chromatography and with the commercial TDX test from the firm Abbott. No side effects caused by the load were observed and all of the patients resorbed Lidocain. Peak concentrations were found both for Lidocain and for MEGX in the 60-minute tests. Patients with liver cirrhosis of different aetiology showed significantly higher Lidocain plasma concentrations and lower MEGX values than patients with chronic non-cirrhotic liver disease. The differentiation of these two groups of patients was most successful via the determination of the 240-minute Lidocain plasma concentration. Oral load with 200 mg Lidocain has turned out to be a practicable and meaningful test for the estimation of the Cytochrom P450-dependent liver function.