Pharmacodynamics and pharmacokinetics of rocuronium in intensive care patients.

Abstract

We have studied dose requirements, recovery times and pharmacokinetics of rocuronium in 32 intensive care patients. After an initial dose of 50 mg, rocuronium was administered as maintenance doses of 25 mg whenever two responses to train-of-four (TOF) stimulation reappeared (bolus group; n = 27) or by continuous infusion to maintain one response in the TOF (infusion group; n = 5). Median requirements for rocuronium were 27.4 (range 14.5-68.3) mg h-1 and 43.7 (30.9-50.3) mg h-1 in patients in the bolus and infusion groups, respectively. Median total duration of rocuronium administration was 29.0 (12.4-95.5) h and 63.4 (24.0-140.3) h, respectively. Median time from administration of the last bolus dose and end of infusion to recovery of the fourth twitch in the TOF was 100 (45-300) min and 60 (15-155) min, respectively. Arterial blood samples were obtained for up to 10 h after cessation of rocuronium administration, and concentrations of the parent compound and its putative metabolites were measured using high pressure liquid chromatography (HPLC). The plasma concentration profile (n = 12) was described adequately by a two-compartment model. Mean plasma clearance (Cl), steady-state distribution volume (Vss), mean residence time (MRT) and elimination half-life (T1/2 beta) were 3.16 (SD 1.15) ml kg-1 min-1, 769 (334) ml kg-1, 262 (120) min and 337 (163) min, respectively. Recovery times, Vss, MRT, and T1/2 beta differed from previously published data obtained after rocuronium infusion of moderate duration in surgical patients.

Use of rocuronium administered by continuous infusion in dogs

“…Three other cases had twitches and spontaneous respiration return before the end of the infusion. This difference may be due to the variation of the individual patient, and if this is the case, titration of the infusion rate to maintain a constant level of blockade with one twitch present throughout the procedure may be required to suit individual patient requirements (Sparr et al. 1997).…”

Effective method of continuous rocuronium administration based on effect-site concentrations using a pharmacokinetic/pharmacodynamic model during propofol–remifentanil anesthesia

“…However, the continuous administration of drugs provides a more stable blood concentration and is more useful in maintaining patient stability under conditions with varying requirements, such as during surgery. Continuous infusions of rocuronium within a short period do not result in accumulation of the drug [2], and its administration for longer durations in intensive care patients results in only a moderately prolonged recovery time [3].…”

Neurally Adjusted Ventilatory Assist Improves Patient-Ventilator Synchrony in a Patient With Tetanus and Unstable Diaphragmatic Electrical Activity

“…It may induce hypoventilation in 0.1-5.0% of cases and respiratory failure in 3.8% due to pleural effusion, pulmonary edema, and respiratory depression. 5 The recovery time for surgical patients who take rocuronium for Ͼ 24 h is longer than for those who take it for Յ 3 h. 6,7 Our patient took rocuronium for 48 h. Magnesium sulfate has been used to control tetanus muscle spasms. 8 It antagonizes calcium in the neuromuscular junction and myocardium, causing muscle weakness when serum levels reach between 20 and 34 mg/dL.…”