ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

One hundred twenty-six parturients for elective cesarean section under general anesthesia were allocated to either a cimetidine or an antacid group in a randomized, double-blind, multicenter trial. The cimetidine-treated group received 300 mg cimetidine orally the evening before the operation and 300 mg intramuscularly between 1 and 3 h preoperatively. The antacid-treated group received 30 ml of Mylanta-II® orally on both occasions. Gastric volume, 30 min after induction of anesthesia and 30 min before response to oral commands, was less in the cimetidine-treated group. GastricpH 30 min after induction was greater in the cimetidine-treated group. The maternal serum level of cimetidine at birth was 1.31 ± 0.12 μg/ml and the umbilical venous level was 0.78 ± 0.05 μg/ml. The neonatal gastric acidity, Apgar scores, and Early Neonatal Neuro-behavioral Scale (ENNS) scores were similar in both groups. No maternal or neonatal complication was attributed to treatment.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The coronary hemodynamic effects of 1% end-tidal isoflurane administered in oxygen-nitrogen by intermittent positive-pressure ventilation (IPPV) were investigated in 21 patients with stable coronary artery disease. Besides standard central hemodynamic measurements, coronary sinus blood flow was measured by continuous thermodilution, and arterial and coronary sinus blood were analyzed for oxygen and lactate. Isoflurane decreased coronary perfusion pressure (-35%) by a combination of systemic vasodilation and decrease in cardiac performance. Coronary sinus blood flow did not change; consequently, coronary vascular resistance was reduced (-26%). Both myocardial oxygen consumption (-36%) and extraction (-29%) were reduced. Ten patients developed ST-T-segment depressions or T-wave inversions in combination with markedly decreased myocardial lactate extraction (-52%) during isoflurane, suggesting regional ischemia. Patients without ECG changes had unchanged myocardial lactate extraction. Intravenous phenylephrine and nitroglycerin were used to restore coronary perfusion pressure to awake control level, and heart rate was kept at control by atrial pacing in the last 10 patients of the series. Five of these patients had ECG and metabolic evidence of regional myocardial ischemia during steady-state isoflurane anesthesia. Coronary blood flow increased to awake control level, and coronary vascular resistance was unaffected. Myocardial oxygen extraction remained at the same low level as during administration of isoflurane alone, suggesting persistent myocardial overperfusion (coronary vasodilation). When perfusion pressure was raised, the ECG changes reverted towards awake pattern in two of the five patients in parallel, with increase in myocardial lactate extraction. In the three remaining patients, ECG remained abnormal, as did myocardial lactate extraction. It is suggested that 1% end-tidal isoflurane induces coronary vasodilation that is not related to normal autoregulation and that both decreased coronary perfusion pressure and redistribution of myocardial blood flow may contribute to development of regional myocardial ischemia.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

d-Tubocurarine has been reported to inhibit the action of dopamine on mollusc neurons. The purpose of the present study was to determine whether or notd-tubocurarine acts as an antagonist on mammalian dopamine receptors. The isolated, perfused rabbit ear artery was the experimental preparation used. In this preparation dopamine and apomorphine produced concentration-dependent inhibition of the response to electrical field stimulation of the periarterial sympathetic nerves.d-Tubocurarine antagonized the inhibitory effect of dopamine and apomorphine in a competitive manner. The calculated dissociation constants ford-tubocurarine acting against dopamine and apomorphine were 1.9 ± 0.6 μM and 1.7 ± 0.5 μM, respectively.d-Tubocurarine (1–100 μM), by itself, did not affect the response of the artery to sympathetic nerve stimulation. Other nicotinic antagonists hexamethonium, pancuronium and mecamylamine did not affect the dopamine action. These results suggest thatd-tubocurarine could attenuate the therapeutic benefit of dopamine if both of these drugs are administered concomitantly.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

This study was designed to compare the effects of three neuro-muscular blocking agents, in a clinically relevant dose range, on the regional distribution of blood flow measured with 15-μm radioactive microspheres in anesthetized, optimally ventilated cats.d-Tubocurarine (400, 800, and 1,600 μg·kg-1) caused hypotension and a decrease in ascending aortic blood flow. Pancuronium (20, 40, and 80 μg·kg-1) only caused a moderate tachycardia, while vecuronium (40, 80, and 160 μg·kg-1) was devoid of any systemic hemodynamic effect. Neither pancuronium nor vecuronium caused major changes in regional blood flows. On the other hand,d-tubocurarine increased blood flow to the stomach but decreased that to the kidneys, liver, skin, spleen, intenstine, and adrenal glands. These effects ofd-tubocurarine show a striking resemblance to those elicited by the infusion of histamine. Blood flow to the nerve-stimulated tibialis anterior muscle, which was about six times that of the unstimulated muscle, was decreased significantly by all three neuromuscular blockers.In conclusion, the results clearly show that, whiled-tubocurarine produces major cardiovascular disturbances, pancuronium and, in particular, vecuronium do not cause serious changes in systemic and regional hemodynamics in doses that are two to four times the ED90 for neuromuscular blocking action.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The authors have studied the effects that hyperbaric pressure and halothane had on measles virus replication. Two per cent halothane at one atmosphere of air (ATA) reduced the number of infectious measles virus particles produced in cultured Vero cells by greater than four orders of magnitude (P< 0.001) relative to virus produced in untreated cultures at 1 ATA. The same concentration of halothane at 100 ATA still reduced the amount of virus synthesized but only by 1 1/2 orders of magnitude (P< 0.01) as compared with control cultures. Pressure (100 ATA) alone reduced virus production insignificantly. Thus, it appears that the antiviral effects of halothane on measles virus replication in cultured Vero cells is reversible at least partially by pressure.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The sensitivity of the respiratory center following a single 0.3 mg·kg-1iv dose of droperidol was determined in eight healthy volunteers by using carbon dioxide (CO2) rebreathing and mouth occlusion pressure measurements (P0.1). There were no significant differences in the mean slopes of the minute ventilation/partial pressure of CO2(VE/PCO2) and log P0.1/PCO2relationships between control measurements and those made 30, 60, 90, 150, and 240 min after droperidol administration. However, individual variations in response were present, one subject showing significant (approximately 50%) depression of respiratory drive.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The brachial plexus sheath was examined in cadavers by suing a combination of anatomic dissection, histologic preparations, and x-rays made after injection of x-ray contrast media, and in surgical patients by using computed tomography (CT) dye studies. The connective tissue forming the sheath was organized more densely proximally near its origin and became loosely organized distally as it ended by joining the medial intermuscular septum of the arm. The connective tissue forming the sheath extends inward, forming septa between components of the plexus. Thus, the sheath is a multicompartmented structure, formed by the thin connective tissue sheath surrounding the plexus and by the septa which extend inward from the sheath. A fascial compartment is created for each nerve, and this compartment serves to define the anatomic limits of that nerve. These compartments have potential clinical importance and implication in the techniques for brachial plexus block. They serve functionally to limit the circumferential spread of injected solutions of local anesthetics. These studies also indicate that injected anesthetic solutions spread easily in a longitudinal manner up and down the nerve and remain compartmentalized. The data presented here provide a rational explanation for the not uncommon occurrence of a profound block of rapid onset in one nerve, yet partial or absent block in other nerves, following any of the techniques of brachial plexus anesthesia.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID

摘要:

The effect of cirrhosis on the pharmacokinetics and plasma protein binding of thiopental was studied in eight patients with cirrhosis, aged (mean ± SD) 42 ± 11 yr, and nine patients with normal hepatic and renal function, aged 48 ± 12 yr, undergoing elective abdominal or orthopedic surgery. The total apparent volume of distribution at steady state was of 2.3 ± 0.5 1·kg-1in the controls and of 3.5 ± 1.9 1·kg-1in the patients with cirrhosis. Thiopental plasma clearance based upon total drug concentrations was 3.9 ± 1.2 ml·min-1·kg-1in the normal group and did not differ significantly in the patients with cirrhosis: 4.4 ± 2.2 ml·min-1·kg-1. The elimination half-life was of 529 ± 97 min in the controls and of 714 ± 252 min in the patients with cirrhosis. The thiopental free fraction was 14.5 ± 3.4% in the controls and was increased significantly to 25.2 ± 3.9% in the patients with cirrhosis. Thiopental intrinsic clearance was decreased insignificantly (P= 0.06) from 28.3 ± 9.0 ml·min-1·kg-1in the controls to 18.2 ± 10.5 ml·min-1·kg-1in those with cirrhosis, suggesting that these patients may have a decreased capacity for thiopental metabolism. These results suggest that the risk of a prolonged effect following thiopental administration appears unlikely in patients with cirrhosis.

ISSN:0003-3022    

出版商:OVID    

年代:1983

数据来源: OVID