The intravenous anesthetics which are commonly used for electroconvulsive therapy (ECT) possess dose-dependent anticonvulsant properties. Since the clinical efficacy of ECT depends on the induction of a seizure of adequate duration, it is important to determine the optimal dose of the hypnotic for use during ECT. We compared the duration of seizure activity and cognitive recovery profiles after different doses of methohexital, propofol, and etomidate administered to induce hypnosis prior to ECT.
Whether anesthetized patients register emotionally charged information remains controversial. We tested this possibility using subanesthetic concentrations of propofol or desflurane. Twenty-two volunteers (selected for hypnosis susceptibility) received propofol and desflurane (on separate occasions, and in a random order) at a concentration 1.5-2 times each individual's minimum alveolar anesthetic concentration (MAC)-awake (or equivalent for propofol).
The spectrum of effects that constitutes the state of general anaesthesia can be induced by the combined use of drugs. Each drug has a predominant action regarding one of the anaesthesia components, hypnosis, analgesia and amnesia. However, each agent, when used in combination, not only produces its own expected effect, but it can also modify the effect of another agent acting on a different component. For example, an opioid, in addition to its anti-nociceptive effect, can also potentiate the hypnotic effect of a benzodiazepine.
The sedative and anesthetic effects of ethanol and propofol when these drugs are coadministered are not known. Accordingly, we investigated the nature of the pharmacological interaction between ethanol and propofol during hypnosis and anesthesia in the mouse. Propofol, ethanol, and mixtures of the two were administered through the tail vein in male CD-1 mice (n = 162). The loss of righting response occurring 10 s after injection and persisting at least 10 s thereafter was defined as hypnosis, and lack of a motor response to tail clamping 60 s after injection was defined as anesthesia.
General anesthesia is a state of reversible, descending depression of the central nervous system that is induced by inhalational or intravenous drugs. Components of general anesthesia include hypnosis, analgesia, amnesia, and muscle relaxation. Recognized anesthesia providers include CRNAs and anesthesiologists. Improvements in pharmacologic agents, technology, and education of providers have sharply reduced morbidity and mortality associated with anesthesia.
Using the Stephens anaesthetic apparatus-which is a closed system with an in-circuit, nonprecision vaporizer-and isoflurane as anaesthetic gas, 18 rabbits were anaesthetized and showed sufficient hypnosis, analgesia, and muscle relaxation during bone surgery. Induction of anaesthesia was achieved with intravenous propofol and all rabbits were intubated afterwards.
BACKGROUND: Anesthetic requirements for inhalational agents are decreased during pregnancy, but there are no data regarding requirements for intravenous agents. The quantal dose-response curves for thiopental were calculated for 70 nonpregnant women having gynecologic surgery and for 70 pregnant women of 7-13 weeks' gestation having elective abortions. METHODS: Groups of 10 patients were given 2, 2.4, 2.8, 3.3, 3.8, 4.5, or 5.3 mg/kg thiopental as a bolus dose during a period of 10 s. Two minutes later, patients were asked to open their eyes as a test for hypnosis.
This study examined the effects of midazolam on the doses of propofol required for the induction of hypnosis and the maintenance of propofol/nitrous oxide anesthesia. In addition, the effects of midazolam on the time to patient recovery, perioperative mood profiles, incidence of perioperative dreams, patient satisfaction scores, and requirement for postoperative analgesics were assessed. This investigation was a prospective, randomized, and double-blind study of female patients undergoing dilatation and curettage.
Propofol is alleged to possess both pro- and anticonvulsant properties, leading to controversy regarding its use in patients with a history of seizures. Since propofol is administered for both sedation and hypnosis, it is important to understand the effects of low (0.5-1.0 mg/kg) and high (2-2.5 mg/kg) doses of propofol on the electroencephalogram (EEG). In this study, the hemodynamic and EEG effects of cumulative doses of propofol from 0.5 to 2.5 mg/kg i.v. were studied in 30 neurosurgical patients with or without a history of seizure disorders.
BACKGROUND: The bispectral index (BIS) measures changes in the interfrequency coupling of the electroencephalogram (EEG). The purposes of this study were (1) to determine whether BIS correlates with responses to command during sedation and hypnosis induced by propofol or propofol and nitrous oxide, and (2) to compare BIS to targeted and measured concentrations of propofol in predicting participants' responses to commands.