Dose-response of tubocurarine in patients with and without renal failure.

Different initial doses of tubocurarine (0.1, 0.2, 0.3 and 0.4 mg kg-1) were given to 20 patients with and 20 patients without renal failure (RF) during standard anaesthesia. Neuromuscular blockade was registered with a device based on electromyography. A fluorescent technique was used to measure plasma tubocurarine concentrations, for which blood samples were drawn during induction and at reversal of neuromuscular block. The dose-response curves for the induction period were slightly steeper in patients with RF. A linear correlation between tubocurarine concentration and twitch response was found in both groups, although the curve had shifted to the left in RF patients. The total amount of tubocurarine used for surgical relaxation was lower in the RF than in the non-RF patients.