pancuronium and Anuria

Topics: Analgesics, Opioid; Anuria; Diagnosis, Differential; Fentanyl; Humans; Infant, Newborn; Male; Neuromuscular Nondepolarizing Agents; Pancuronium; Urethra

Pharmacokinetic data of tubocurarine, gallamine, alcuronium and pancuronium in patients with normal and without renal function are taken from the literature. They are adapted to an open three compartment pharmacokinetic model, and the proportional intercompartmental distribution is calculated as a function of time from 1 min to 8 h. All drugs show similar kinetic properties: During the first 10 min rapid disappearance from compartment 1 results in saturation of compartment 2. Maximum saturation of compartment 3 is achieved after 1 to 2 h followed by a gradual disappearance of the relaxants from the whole system. 20-25% of the dose undergo sequestration apart from intercompartment equilibrium. In normal individuals sequestration is observed after 2 to 3 h whereas in anuric patients it is already demonstrated during the first hour. Intercompartmental redistribution is the basic principle governing the pharmacodynamic profile of all of the four drugs if given in clinical dosage.

Topics: Alcuronium; Anuria; Gallamine Triethiodide; Humans; Neuromuscular Nondepolarizing Agents; Pancuronium; Time Factors; Tubocurarine

Plasma concentration curves of patients with normal and impaired renal function are fitted to a tri-exponential function according to an open three compartment pharmacokinetic model. A detailed discussion of the relationship between theoretical distribution volumes, clinical pharmacodynamics and morphological or biochemical structures provides the basis for the concept of a central application and measuring compartment, a pharmacologically specific compartment and a non specific one. The distirbution of pancuronium from the application compartment to the specific compartment results in the onset of muscular paralysis. The recovery is governed by renal elimination of the unchanged drug as well as by its redistribution into the non specific compartment. In anuric patients the spontaneous recovery after 3--4 h is the effect of redistribution only. Neither metabolic degradation nor increased biliary elimination can sufficiently compensate for the lack of the renal pathway. The clinician should always keep in mind that after the recovery from pancuronium-induced muscular paralysis, both in patients with or without renal pathology, considerable residues of the active drug are stored at nonspecific and even specific receptor sites for many hours.

Topics: Anuria; Biliary Tract; Humans; Kidney; Pancuronium; Paralysis; Receptors, Drug

After a single intravenous dose of 6 mg serum concentrations of pancuronium were measured in 6 anuric patients by means of the bromophenol blue colorimetric method at 1, 5, 45 min and 3 h. After 45 min and 3 h there was a retention of 1.7 and 4 times the control values respectively. The prolongation of pancuronium induced muscular paralysis which has been demonstrated by other authors now can definitely be related to elevated serum concentrations of the active drug. The termination of muscle relaxation in anuric patients is considered merely to be due to redistribution of the drug from the motor end plates to non specific structures. Prolonged neuromuscular blockade may occur in as much as the redistribution mechanism is overloaded by inadequate doses.

Topics: Adult; Aged; Anuria; Colorimetry; Female; Humans; Male; Pancuronium; Time Factors