Halothane, independent of oxygen tension, increased the signal of the gold/silver-silver chloride microelectrode. The output of microelectrodes at different oxygen tensions in the presence of increasing amounts of halothane has been measured. Halothane causes an increase in the electrode signal which is proportional to its concentration. This effect results from the polarographic reduction of h...

BACKGROUND Halothane is extensively (approximately 50%) metabolized in humans and undergoes both oxidative and reductive cytochrome P450-catalyzed hepatic biotransformation. Halothane is reduced under low oxygen tensions by CYP2A6 and CYP3A4 in human liver microsome to an unstable free radical, and then to the volatile metabolites chlorodifluoroethene (CDE) and chlorotrifluoroethane (CTE). The ...

BACKGROUND Previously, the authors have shown in Ca(2+)-clamped skinned arterial strips that protein kinase C (PKC) plays a role in 3% halothane- or isoflurane-increased force. PKC in the pulmonary artery and Ca(2+)-calmodulin-dependent protein kinase II (CaMKII) in the femoral artery have been implicated in isoflurane-induced relaxation. For this study, the authors used clinical concentrations...

Diaz-Sylvester PL, Porta M, Copello JA. Halothane modulation of skeletal muscle ryanodine receptors: dependence on Ca , Mg , and ATP. Am J Physiol Cell Physiol 294: C1103–C1112, 2008. First published February 27, 2008; doi:10.1152/ajpcell.90642.2007.—Malignant hyperthermia (MH) susceptibility is a genetic disorder of skeletal muscle associated with mutations in the ryanodine receptor isoform 1 ...

BACKGROUND Recent studies suggest that anesthetics such as isoflurane act in the spinal cord to suppress movement that occurs during noxious stimulation. The authors examined the effect of halothane and thiopental on suppression of noxious-evoked movement using a model of differential anesthetic delivery. They hypothesized that halothane and thiopental, similar to isoflurane, would suppress mov...

Background: Halothane is the routine used inhalation anesthetic drug in the world but at present, there is an increasing interest for using intravenous anesthetics like propofol. The purpose of this study was to compare these anesthetic effects on hepatic enzymes.Methods: From 2006 to 2007, this study was performed on fifty eight patients classified in class I of American Society of Anesthetics...

Twenty-three patients undergoing Caesarean section received either 0.5% halothane or 0.8% isoflurane to supplement nitrous oxide-oxygen anaesthesia. We studied the rate of uptake of the agents by the mother and fetus by measuring partial pressures in maternal arterial (Pa) and fetal umbilical venous (Puv) blood. Mean induction-delivery interval did not differ between the halothane (10.8 min) an...

It is generally accepted that halothane reduces airway and tissue resistance in lungs with preexisting airway tone. However, under conditions of resting airway tone, pulmonary resistance remains unaltered. In this study, we have determined the effects of halothane on respiratory system, pulmonary and chest wall resistive, elastic and viscoelastic mechanical properties, and related the results t...

BACKGROUND The Bispectral Index (BIS) has been calibrated for several general anaesthetic agents including isoflurane. Halothane is still used in paediatric anaesthesia. Compared with other volatile anaesthetics, halothane has a different receptor affinity and differing effects on the EEG. There are limited data evaluating the BIS with halothane. We set out to compare the BIS using halothane an...

To determine if clinical concentrations of halothane have direct relaxant effects on airway smooth muscle, the authors compared dose-response curves to histamine in the control state (thiopental) and during halothane anesthesia (1.0 and 1.5 MAC), in six basenji-greyhound (BG) dogs untreated and pretreated with atropine aerosols (10 mg X ml-1). Pulmonary resistance (RL) and dynamic compliance (C...