Comparative absorption kinetics of intramuscular midazolam and diazepam.

Purpose: This study investigates the rate and extent of absorption following intramuscular injection of midazolam and diazepam.

Methods: Four healthy male volunteers were recruited in this randomized three-way cross-over study. On one occasion each subject received simultaneous im injections of 5 mg midazolam and 10 mg diazepam in separate deltoid muscles.

Pharmacokinetics of inhaled liposome-encapsulated fentanyl.

Background: Pulmonary administration of fentanyl solution can provide satisfactory but brief postoperative pain relief. Liposomes are microscopic phospholipid vesicles that can entrap drug molecules. Liposomal delivery of fentanyl has the potential to control the uptake of fentanyl by the lungs and thus provide sustained drug release.

Fentanyl-induced rigidity and unconsciousness in human volunteers. Incidence, duration, and plasma concentrations.

Background: Muscle rigidity frequently accompanies induction of anesthesia with opioids. The authors sought to determine whether unconsciousness and amnesia occur when humans develop rigidity and apnea after intravenous fentanyl (without other concomitant anesthetics).

Methods: The incidence and duration of rigidity and level of consciousness were evaluated and associated plasma concentrations of fentanyl were measured in 12 healthy adult male volunteers given only intravenous fentanyl.

Application of semilinear canonical correlation to the measurement of opioid drug effect.

To examine the relationship between the electroencephalograph (EEG) and plasma opioid concentration, one would like to collapse the high-dimensional EEG signal into a univariate quantity. Such a simplification of the EEG is desirable because a univariate quantity can be modeled using standard nonlinear regression techniques, and because most of the information in the EEG is redundant or unrelated to drug concentration. In previous studies of the EEG response to opioids, the manner in which a univariate component was extracted from the EEG was ad hoc.

Thiopental pharmacodynamics. II. Quantitation of clinical and electroencephalographic depth of anesthesia.

This study examined the relationship among pseudo-steady-state (constant) serum thiopental concentrations, clinical anesthetic depth as assessed by several perioperative stimuli, and the electroencephalogram (EEG). Twenty-six ASA physical status 1 or 2 patients participated in the study. Two constant serum thiopental concentrations were maintained in each patient using a computer-controlled infusion pump.