Influence of chronic phenytoin administration on the pharmacokinetics and pharmacodynamics of vecuronium.

Background: The duration of action of vecuronium is reduced in patients receiving phenytoin. In this study, the authors examined, simultaneously, the influence of phenytoin on both the pharmacokinetics and the pharmacodynamics of vecuronium.

Methods: This study was approved by the institutional review board of the University of California, San Francisco, and patients gave written informed consent.

Intraoperative monitoring for safety of bilateral total knee replacement.

Cardiopulmonary hemodynamics in 79 consecutive patients who had one-stage bilateral total knee replacements were monitored prospectively with a pulmonary artery catheter. The pulmonary vascular resistance, wedge pressure, pulmonary artery pressure, and systemic vascular resistance were measured before skin incision, 5 to 10 minutes after implanting the first total knee replacement, and after the second knee replacement. The second knee replacement was cancelled in five patients because the pulmonary vascular resistance after the first knee replacement was more than double the baseline, or above 200 dyne/second/cm(5).

Effect of edrophonium and neostigmine on the pharmacokinetics and neuromuscular effects of mivacurium.

Background: Previous studies demonstrated that both edrophonium and neostigmine affect mivacurium's pharmacokinetics, thereby potentially affecting its recovery profile. However, those studies were not clinically relevant because mivacurium was still infused after the antagonists were given. In the present study, the authors gave antagonists (or placebo) after discontinuing a mivacurium infusion, thereby obtaining data that are more clinically relevant.

Temperature-dependent pharmacokinetics and pharmacodynamics of vecuronium.

Background: The authors evaluated the influence of temperature on the pharmacokinetics and pharmacodynamics of vecuronium because mild core hypothermia doubles its duration of action.

Methods: Anesthesia was induced with alfentanil and propofol and maintained with nitrous oxide and isoflurane in 12 healthy volunteers. Train-of-four stimuli were applied to the ulnar nerve, and the mechanical response of the adductor pollicis was measured.

Influence of renal failure on the pharmacokinetics and neuromuscular effects of a single dose of rapacuronium bromide.

Background: Because renal function affects the elimination of muscle relaxants, each new muscle relaxant must be evaluated in patients with renal failure. Accordingly, the neuromuscular effects and pharmacokinetics of rapacuronium were identified in patients with renal failure.

Methods: Rapacuronium (1.