摘要:

Minimal anesthetic requirements for cyclopropane, nitrous oxide, thiopental, ether, halothane, and methoxyflurane in the toad were studied. Requirements in the toad at room temperature were similar to those in the dog and in man at body temperature. The effect of temperature on halothane requirements in the toad was comparable to the effects of temperature in the goldfish and the dog. When halothane and methoxyflurane were carried in 100 per cent oxygen anesthetic requirements were higher than with 20 per cent oxygen. It made no difference whether nitrogen or helium was the third gas. Reserpinization of the toads abolished this effect of oxygen on anesthetic requirements, decreased anesthetic requirements, and reduced catecholamine concentrations in myocardium and brain.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

摘要:

The effects of cyclopropane, nitrous oxide, thiopental, ether, halothane, and methoxyflurane on sodium transport in the isolated toad bladder were studied. All agents affected sodium transport in the same way: stimulation at low concentrations; inhibition at high concentrations. Stimulation may be the result of positive interaction with catecholamines on the serosa, inhibition the result of a mucosal effect. The balance between stimulation and inhibition of sodium transport in vitro appeared unrelated to the anesthetic effect in vivo.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

摘要:

The effects of anesthesia on pulmonary antibacterial defense mechanisms of the murine lung were assessed quantitatively. Following infection with aerosols of32P-labelled S. aurcus, mice were anesthetized to approximately equivalent levels with halothane, pentobarbital, methoxyflurane or cyclopropane. After four hours of anesthesia, the animals were sacrificed and the rate of radiophosphorus removal and intrinsic pulmonary bactericidal activity were determined by established techniques. Anesthesia with methoxyflurane or cyclopropane significantly depressed pulmonary bactericidal activity. Anesthesia with halothane or pentobarbital did not affect bactericidal activity. None of the anesthetics altered the rate of physical removal of bacteria. The adverse effects of methoxyflurane and cyclopropane could not be attributed to changes in body temperature or blood-gas composition.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

摘要:

The reduction in the amount of methoxyflurane needed for anesthesia by addition of nitrous oxide was determined in 16 patients undergoing elective operations. Sixty per cent inspired nitrous oxide decreased methoxyflurane MAC to 0.070 per cent. Compared with the previously reported MAC value of 0.16 per cent for methoxyflurane alone, this represents a 56 per cent reduction in methoxyflurane anesthetic requirement. All patients moved when alveolar concentration was below 0.066 per cent; with one exception, no patient moved when alveolar methoxyflurane was above 0.072 per cent. It is estimated that the minimum alveolar concentrations of fluroxene (Fluoromar), halothane (Fluothane) and methoxyflurane (Penthrane) will be decreased about 1 per cent for every 1 per cent alveolar nitrous oxide.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

摘要:

Twenty patients without clinical evidence of cardiopulmonary disease were studied before and during constant infusions of norepinephrine and isoproterenol to assess the effects of these drugs upon blood-gas tensions during breathing of 100 per cent oxygen.Norepinephrine was usually associated with an increase in arterial oxygen tension and a decrease in A-aDo2while isoproterenol was associated with a decrease in arterial oxygen tension and an increase in A-aDo2. A significant decrease in the mean venous admixture (&OV0422;S/&OV0422;T) was observed with norepinephrine, while the reverse was seen with isoproterenol. The data suggest that isoproterenol interferes with the hypoxic pulmonary pressor response, while norepinephrine enhances this compensatory response which minimizes the arterial hypoxemia resulting from regional alveolar hypoventilation.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

摘要:

The concentrations of cortisol metabolites, 6-β-hydroxycortisol (6-OHF) and 17-hydroxycorticosteroids (17-OHCS), were measured in 24-hour urine specimens obtained before and during treatment of four healthy male volunteers with pentobarbital, 2 mg/kg, administered twice in a 12-hour period. There were definite increases in the excretion of 6-OHF in the urine of all four subjects after pentobarbital. Urinary 17-OHCS remained essentially unchanged. To determine whether this effect on cortisol metabolism was drug-specific, the study was repeated with another 13 volunteers using randomized double-blind conditions. There were higher concentrations of 6-OHF in the urine of subjects given the drug than in the urine of those given the placebo. The excretion of 17-OHCS in the pentobarbital-treated group was not significantly different from excretion in the control and placebo-treated groups. These results indicate that pentobarbital acutely increased the secretion of 6-OHF relative to total 17-OHCS, suggesting that pentobarbital is capable of stimulating hepatic microsomal hydroxylase activity. This raises the possibility that the urinary metabolites of cortisol may provide an indirect index of acute enzyme induction in man.

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1971

数据来源: OVID