Comparison of vecuronium, atracurium and tubocurarine in normal patients and in patients with no renal function.

Vecuronium (initial dose 0.1 mg kg-1; incremental doses 0.04 mg kg-1) was given to 21 normal and 21 anephric patients. There were no gross differences between the two groups in the effect or in the duration of action of either initial or incremental doses, except in two anephric patients who were resistant to the agent. Reversal with neostigmine was satisfactory. In normal patients the initial dose of vecuronium was slower in onset of action than was atracurium 0.5 mg kg-1 (26 patients): the first two incremental doses of vecuronium were administered significantly earlier than the corresponding increments of atracurium (0.2 mg kg-1), but the duration of action of increments over-all was not greatly different. However, in anephric patients, except in the resistant patients, the behaviour of vecuronium was similar to that of atracurium (26 patients). A comparison with an initial dose of tubocurarine 0.5 mg kg-1 given to 20 anephric patients and tubocurarine 0.6 mg kg-1 given to 21 normal and 20 anephric patients showed tubocurarine to be longer acting and considerably less predictable. This was particularly so in the anephric group, in which its action sometimes persisted after neostigmine had been given.