A pharmacodynamic model for pancuronium.

It has been demonstrated that a simple two-compartment kinetic model may account for the changes in plasma concentration of pancuronium after i.v. administration. However, it can be shown that this simple model does not account satisfactory for the observed changes in muscle twitch response. By the addition of a receptor (biophase) compartment, twitch response can be reconciled with model behavior and the characteristics resemble those predicted by animal studies. The complete model is applied to the problem of total renal failure, and shows that patients with this condition are likely to be marginally resistant to small doses of pancuronium, with a normal rate of recovery. However, larger doses are likely to result in delayed recovery, the duration of effect increasing in a dose-dependent manner.