ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

A modification of the single-breath nitrogen closing volume (CV) test allows measurement of closing capacity (CC) during general anesthesia. In tlie modification, inspiration and expiration are mechanically produced by a hydraulically powered cylinder. For 14 awake, normal subjects, results of the CV test performed using this mechanical method differed than those obtained following spontaneous inspiration and expiration. Mean (±SE) CC's were 2.25 (±0.15) and 2.421 (±0.14) (P< 0.01) using spontaneous and mechanical methods, respectively. The slopes of Phase III of the CV traces were 2.24 (±0.27) and 2.66 per cent N2/I (±0.32) (P< 0.01), respectively. To eliminate differences due to measurement technique, the modified CV test was used both before and during anesthesia with halothane in 70 per cent N2in 11 normal, supine, spontaneously breathing subjects. CC's were 1.891 (±0.16) before and 1.841 (±0.15) during anesthesia (P> .5). Mean functional residual capacities (FRC) by the closed-circuit helium method were 1.771 (±0.15) before and 1.451 (±0.17) during anesthesia (P< .001). With CC unchanged and FRC decreased following induction. CC/FRC increased from 1.07 (±0.08) to 1.37 (±0.11) (P< .005), suggesting increased small-airway closure during anesthesia.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Fluoride concentrations in maternal and fetal benes were measured following exposure of pregnant rats to methoxyflurane or enflurane anesthesia. Fluoride content in fetal bone increased significantly only after exposure to methoxyflurane, and then only when methoxyflurane was administered after 12 days of gestation, when ossification of fetal bone begins. Fluoride concentrations in maternal bone increased following both anesthetics, except in rats exposed to methoxyflurane after 15 days of gestation, when ossification of many fetal skeletal parts is in progress and fluoride is preferentially deposited in the fetal skeleton.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Epidemiologic and animal studies identify a relationship between chronic exposure to anesthetic gases and health hazards. Efforts to reduce exposure of personnel require an understanding of the distribution of anesthetic waste gases in the operating room air. Concentrations ol nitrous oxide and halothane were measured at numerous stations throughout an operating room and a delivery room in the absence of personnel. Air conditioning flow rates and flow patterns were varied, as was the height of the anesthetic gas source. Air flow patterns were found to dominate the anesthetic gas distribution, while buoyaney effects were neligible. Venting waste gases at the floor does not significantly reduce exposure of personnel. Areas of high concentration were observed; their occurrences and locations varied strongly with air flow patterns. The exhaust grille is the best location for a single measurement of the average room concentration. Recirculating air-conditioning systems reduce energy costs; however, only the non-recirculating portion of the air exchanges reduces waste gas concentrations.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Trained dogs with chronically implanted catheters and left ventricular (LV) pressure transducers were anesthetized with 2.3 per cent (1 + MAC) and 3.6 per cent enflurane. Left ventricular function and metabolism were studied while the dogs were awake and during exposure to the two anesthetic concentrations. Enflurane depressed LV function in a dose-dependent fashion. Myoeardial blood flow and oxygenation mirrored the functional changes. Mayocardial oxygen extraction decreased and lactate extraction incrcased during enflurane anesthesia, suggesting adequate oxygen delivery to the myocardium. Low concentrations of halothane in the same dogs on different days had similar effects. However, 2 MAC halothane resembled 1.6 MAC enflurane, suggesting that the cardiovascular dose-effect curve for enflurane is steeper than that for halothane. Both anesthetics produce dose-dependent negative inotropic effects in the intact dog, accompanied demand. Contrary to previous suggestions, enflurane appears to be at least as depressant to the dog heart as halogthane.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

The time of onset and duration of tlie anti recall action of Iorazcpam were assessed under clinical conditions by measuring recall and rccognition of visual stimuli 24 hours after intravenous administration of Iorazepam. The visual stimuli were first presented 5–240 minutes after 2 mg and 5–360 minutes after 4 mg Iorazepam. Retrograde amnesia was not produced. Lorazepam, 2 mg produced a short anti-recall effect (enterograde amnesia) in 50 per cent of the cases with a latency of 30 minutes and a duration of less than half an hour. Duration and frequency of the anti-recall effect were greater after 4 mg while the latency was shorter. More than 70 per cent of the individuals tested were amnesia for the visual stimuli 15 minutes to 4 hours after 4 mg lorazepam. Sedation was satisfactory and long-lasting following both doses of lorazepam, but was not related to the antirecall effect.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

One hundred and twenty-eight Sprague-Dawley rats were each anesthetized with one of four anesthetics and subjected to a standard hemorrhage protocol to determine the effects of anesthetics on survival following hemorrhage. The anesthetics studied were: halothane, 1.26 vol per cent: flurovene 4.5 vol per cent: pentobarbital. 50 mg/kg. ip: ketamine. 125 mg/kg im. Meand arterial pressure was controlled at 40 torr during 60 minutes of hemorrhage. Cumulative survical rates were determined at the end of hemorrhage and 24 hr. 48 hr. 72 hr and 7 days after hemorrhage. Twentyfour-hour survival rates were: halothane, 50.0 per cent: fluroxene. 56.3 per cent: pentobarbital. 59.4 per cent: ketamine, 84.4 per cent. Seven-day survival rates were: halothane, 46.9 per cent: fluroxene. 18.7 per cent: pentobarbital, 53.1 per cent: ketamine, 81.3 per cent. Survival rates were significantly higher (P≤ 0.05) in animals anesthetized with ketamine compared with survival rates associated with the other anesthetics. Long-term (72-hr and seven-day) survival rates were significantly (P≤ 0.05) lower in animals anesthetized with fluroxene. Microscopie examination of livers and small intestines revealed significantly fewer (P≤ 0.05) pathologic changes in the splanchnic organs of hemorrhaged rats anesthetized with ketamine compared with wnimals anesthetized with the other drugs.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

摘要:

Pulmonary shunling (&OV0422;t,/&OV0422;t, with FIO2= 1) was measured in 18 anesthetized patients during deliberate hypotension. Hypotension was induced in 12 patients with sodium nitroprusside and light halothane anesthesia and in six others with deep halothane anesthesia and mechanical hyperventilation. Similar results were observed in the two groups. During the hypotensive period mean arterial pressure (MAP) was reduced to 49 ± 2 torr, a 37 per cent decrease from the control level after the onset of operation and a 40 per cent decrease compared with the recovery level during closure of the wound. &OV0422;t/&OV0422;t, however, remained unchanged throughout the study; 52 ± 0.9 per cent initially, 5.4 ± 0.8 per cent during hypotension, and 4.7 ± 0.5 per cent during recovery. It is concluded that pulmonary shunting need not develop during dliberate hypotension induced with either technique.

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1976

数据来源: OVID