摘要:

To determine the effect of nitrous oxide on the body's response to venous carbon dioxide (CO2) embolization, the authors compared changes in mean pulmonary arterial pressure (MPAP) following intravenous injections of CO2in pentobarbital-anesthetized dogs breathing 100 per cent oxygen (O2) or nitrous oxide–oxygen, 79:21 per cent (N2O). When CO2was infused intravenously in seven dogs at a rate of 3 ml/kg/min the volume of injected CO2needed to increase MPAP to 40 per cent above control during breathing of O2was approximately 5.5 times the volume necessary during inhalation of N2O. In a second group of eight dogs, breathing N2O, compared with O2or air, resulted in a significantly greater increase and duration of increase in MPAP following a bolus injection of CO2of 20, 40 or 80 ml. The data suggest that breathing nitrous oxide intensifies and prolongs the effect of CO2bubbles in blood. While the magnitude of insult following intravenous injection of CO2is about 6.5 times less than that for a similar volume of air, avoidance of nitrous oxide should be considered in management of patients in whom CO2embolism is possible.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Accuracy and reliability of cardiac output (±Qtmeasurement utilizing computer analysis of the aortic pressure wave (Warner method) were assessed by comparing this technique with a standard thermodilution method in 20 halothane-anesthetized dogs over a wide range of ±Qtand systemic vascular resistance (SVR) values. Five of the dogs also had electromagnetic flow (EMF) probes placed around the ascending aorta. More than 800 pairs of simultaneous ±Qtdeterminations were performed using pulse-wave and thermodilution methods, and more than 150 triplicate measurements made using all three techniques during changes in inspired halothane concentrations (0.5–2.0 per cent) or during infusions of sodium nitroprusside (SNP) and phenylephrine (PE). Cardiac out±puts ranged from 0.7 to 5.3 1/min, mean aortic blood pressures (BP) ranged from 30 to 200 torr, and SVR varied from 70 per cent below to 200 per cent above control values. Correlation of pulse-wave-computed and thermodilution-calculated ±Qtvalues was high (r = .91 or better), irrespective of SVR during changes in halothane concentration. Correlation of pulse-wave and EMF methods was equally good during this period (r = .92 or better). Correlation was lower, but still good, with alterations in SVR of 30 per cent or less induced by SNP or PE (r = .90 or better for thermodilution and r = .91 or better for EMF). When SVR was changed from 30 to 50 per cent of control with SNP or PE, correlation between pulse-wave-computed and EMF ±Qtvalues remained good (r = .85), but correlation between pulse-wave-computed and thermodilution-calculated ±Qtvalues was only fair (r = .79–.77). Correlation of thermodilution-calculated or EMF and pulse-wave-computed ±Qtvalues deteriorated significantly with SNP. and PE-induced changes of SVR greater than 50 per cent (r = <.5). These results demonstrate that computer analysis of the aortic pressure wave is a simple and valid method of determining ±Qtduring halothane anesthesia, but must be limited to conditions of only moderate alteration of SVR during infusions of vasopressor or vasodilator drugs.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

This report describes the construction of a range of linear resistance units from 5 to 1,000 cm H2O/±I/sec for use in testing ventilators in accordance with theAmerican National Standards for Breathing Machines for Medical Use(ANSI Z79.7, 1976). Various filter materials housed inside a Bird water trap are employed to produce the desired resistance values. Pressure and flow measurements showed that the units were sufficiently linear (within ±20 per cent) over a flow range of from 0 to 1/l/sec.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Monitoring the degree of neuromuscular block during anesthesia has become a routine and valuable practice in the last few years.1Three recent cases have demonstrated that monitoring with the peripheral-nerve stimulator may be unreliable and misleading in patients with upper-motor-neuron lesions.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

Ketamine hydrochloride is a popular drug for producing immobility during radiation therapy in young children. In certain patients methohexital sodium, 5 per cent, given by deep intramuscular injection has also proven to be a useful agent for this purpose. We present a case in which convulsions occurred following treatment with methohexital sodium.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

摘要:

The most common complications of radial arterial catheterization are thrombus, embolus and hematoma formation,1–4usually detected prior to or shortly after decannulation. We report the uncommon occurrence of pseudoaneurysm formation 18 days after decannulation in a patient who had an otherwise uncomplicated hospital course.

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID

ISSN:0003-3022    

出版商:OVID    

年代:1980

数据来源: OVID