Journal of anesthesia
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Journal of anesthesia · Mar 1994
The effects of low-dose midazolam for induction of high-dose fentanyl anesthesia for coronary artery bypass graft.
A small dose of midazolam 0.06 mg/kg or diazepam 0.15 mg/kg was used for induction of high-dose fentanyl (50 μg/kg) anesthesia in patients undergoing coronary artery bypass grafting operation. Hemodynamic variables were measured 5 min after the injection of midazolam or diazepam, after the end of the fentanyl infusion, and following endotracheal intubation. ⋯ Heart rate was decreased in the diazepam group but not in the midazolam group. Therefore, a small dose of midazolam may be a suitable induction agent for high-dose fentanyl anesthesia in patients with coronary artery disease.
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Journal of anesthesia · Mar 1994
Clonidine premedication for sevoflurane anesthesia in upper abdominal surgery.
The effects of clonidine as a preanesthetic medication were compared with diazepam on clinical courses of sevoflurane anesthesia in 22 patients undergoing upper abdominal surgery. The patients were divided into two groups of 11 patients each according to preanesthetic medication: atropine 0.5 mg i.m. plus clonidine 0.3 mg p.o., or atropine 0.5 mg i.m. plus diazepam 10 mg p.o. 60-90 min prior to induction of anesthesia. Anesthesia was induced with fentanyl and thiopental, and was maintained with sevoflurane, 0.5%-1.5%, nitrous oxide and oxygen, supplemented with fentanyl, 0.5 μg·kg-1·hr-1. ⋯ Pain score after extubation was higher in the diazepam group than in the clonidine group. The time when patients responded to verbal command after discontinuation of anesthetics was similar in both groups. Therefore, clonidine pretreatment was useful for sevoflurane anesthesia in upper abdominal surgery.
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Journal of anesthesia · Mar 1994
Subanesthetic sevoflurane does not affect sympathetic or parasympathetic function.
To evaluate the effects of subanesthetic enflurane and sevoflurane on the sympathetic nervous system (SNS) and the parasympathetic nervous system (PNS), the blood level of norepinephrine (NE) and fluctuations in the R-R intervals were measured on electrocardiogram in humans given either 0.5 MAC enflurane or sevoflurane. Enflurane suppressed circulating plasma NE and elevated coefficients of variation (CV) of R-R intervals after 20 and 30 min of inhalation. ⋯ Sevoflurane lowered the CV to 84% of control after 30 min of inhalation. These results indicate that subanesthetic concentrations of sevoflurane are unlikely to perturb sympathetic and parasympathetic activities in humans without surgical stimulation when compared with enflurane.
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Journal of anesthesia · Mar 1994
Electrophysiologic effects of volatile anesthetics, sevoflurane and halothane, in a canine myocardial infarction model.
The effects of sevoflurane and halothane on the effective refractory period (ERP) and ventricular activation were examined in a canine myocardial infarction model. Sevoflurane (1 MAC) reduced the heart rate and prolonged ERP in both normal and infarcted zones. A prolongation of ERP with sevoflurane was observed also during atrial pacing at a fixed rate, but the effect was less than during sinus rhythm. ⋯ Halothane (1 MAC) prolonged ERP during sinus rhythm and atrial pacing, but to a lesser extent during the latter. Halothane also depressed ventricular activation in the infarcted zone during atrial pacing. In conclusion, sevoflurane as well as halothane selectively depresed the delayed activation and the prolongation of ERP in myocardial infarction, which may inhibit ventricular arrhythmias in myocardial infarction.
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Journal of anesthesia · Mar 1994
Effects of a forced-air system (Bair Hugger, OR-type) on intraoperative temperature in patients with open abdominal surgery.
Intraoperative hypothermia is difficult to avoid and may present a significant clinical risk during the early postoperative phase. We evaluated a forced-air system [Bair Hugger, OR-type (BH)] for warming intraoperative patients with open abdominal surgery. Twenty patients received BH warming [BH(+) group] and another 20 patients, who served as controls, did not [BH(-) group]. ⋯ Rectal and fingertip temperatures in the BH(+) group were significantly higher than those in the BH(-) group, and central-peripheral temperature gradients in the BH(+) group were significantly smaller than those in the BH(-) group during the study, except at 180 min. No shivering occurred in either group. Therefore, BH is an effective warming device during open abdominal surgery.