Beagles, implanted with cortical and subcortical electrodes, were given etomidate i.v. (1 mg/kg) over a period of 10 sec. The effects on the EEG were compared with those obtained with 7 mg/kg of methohexital. Both compounds induced hypnosis for a duration of approximately 8 min. The EEGs showed a remarkable similarity. Visual inspection of the records as well as power spectrum analysis revealed a sustained theta-activity with underlying fast activity. The configuration of the waves was rather sharp.
Archives Internationales De Pharmacodynamie Et De Thérapie
The antidiarrheal drugs loperamide and diphenoxylate were tested for their ability to potentiate central nervous system depression induced by ethanol in mice and nethohexital in rats. Oral diphenoxylate potentiated the loss of righting reflex (hypnosis) at 10 mg/kg in mice and at 5 mg/kg in rats, doses which were considerably lower than those required to induce morphine-like behavior in mice and rats. Oral loperamide did not potentiate hypnosis.
An approach to outpatient anesthesia using drugs that have reversible or very short-acting effects is described, along with a method of monitoring patients using pulse rate to assess tranquility. Preoperatively, the patient is given 1 mg of lorazepam the evening before surgery and sublingual lorazepam 1 mg combined with hydroxyzine 50 mg intramuscularly one hour before surgery. Before infiltration of local anesthesia, intravenous diazepam in 2.5 mg increments is given if needed, followed by a mixture of meperidine and pentazocine intravenously in exactly a 10:1 ratio.
Fifty-two female patients who underwent gynaecological operations as day cases received either a short pre-operative hypnotic induction or a brief discussion of equal duration. Hypnotized patients who underwent vaginal termination of pregnancy required significantly less methohexitone for induction of anaesthesia. They were also significantly more relaxed as judged by their visual analogue scores for anxiety. Less than half of the patients were satisfied with their knowledge about the operative procedure even after discussions with the surgeon and anaesthetist.
We studied the effects of atipamezole, an alpha 2-adrenoceptor antagonist, on hypnosis induced by medetomidine, an alpha 2-adrenoceptor agonist (1 mg/kg IP), and pentobarbital (40 mg/kg IP) by testing the righting reflex in the rat. The duration of antinociception was assessed with repeated pinch tests. Medetomidine-induced hypnosis and antinociception were inhibited by atipamezole at doses greater than 0.1 mg/kg. Atipamezole restored the righting reflex at a dose ratio that was 1:10 or more to that of medetomidine used to induce hypnosis.
The influence of methohexital and propofol on seizure activity and recovery profiles was assessed in a randomized, crossover study involving 13 adult outpatients undergoing electroconvulsive therapy (ECT). Arterial blood pressure, heart rate, hemoglobin oxygen saturation, and electroencephalogram (EEG) activity were monitored during the ECT procedure. After premedication with glycopyrrolate, 0.2 mg intravenously (i.v.), and labetalol 20-30 mg i.v. hypnosis was induced with a bolus injection of either methohexital or propofol, 0.75 mg/kg.
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.