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1.
J.A. Hannam S.J. Mitchell D. Cumin C. Frampton A.F. Merry M.R. Moore C.J. Kruger 《British journal of anaesthesia》2019,122(2):198-205
Background
Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.Methods
Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.Results
The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).Conclusions
Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.Clinical trial registration
Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651. 相似文献2.
Steven Elia Peter Liu Carol Chrusciel Alan Hilgenberg Charrisios Skourtis Demetrios Lappas 《Journal canadien d'anesthésie》1989,36(1):2-8
Global coronary blood flow and metabolism were measured in seven patients on the first postoperative day following coronary
revascularization to test the hypothesis that tracheal extubation produces adverse haemodynamic responses akin to those observed
during tracheal intubation. Regional coronary flow and metabolic measurements were made in five of the seven patients. Extubation
from a continuous positive airway pressure (CPAP) of 5 cm H2O was associated with a statistically significant rise in cardiac index from 3.44 ± 0.23 L · min-1 · m-2 to 3.73 ± 0.15L·min-1 ·m-2 related to an increase in stroke index, without significant changes in heart rate, mean arterial and pulmonary capillary
wedge pressure. Consequently the changes in myocardial oxygen consumption (8.52 ± 0.55 to 8.85 ± 0.93 ml · min-1) and coronary blood flow (172 ± 18 to 179 ± 17 ml·min-1) were less prominent than those reported during intubation, where substantial rises in myocardial oxygen consumption and
coronary flow occurred. Two patients experienced cardiac lactate production but there were no changes in systemic or coronary
haemodynamics, nor were there clinical or electrocardiographic signs of ischaemia. We conclude that extubation does not appear
to be associated with adverse systemic or coronary haemodynamic responses in patients following coronary bypass grafting.
However, the revascularized myocardium may remain vulnerable to anaerobic metabolism in the immediate postoperative period.
Pour savoir si comme ľintubation, ľextubation de la trachée provoque des perturbations hémodynamiques, on a mesuré le métabolisme
et la circulation coronarienne globale chez sept patients, au lendemain ďun pontage aorto-coronarien. On a aussi calculé les
valeurs régionales de ces mêmes variables pour cinq ďentre eux. Ľindex cardiaque de 3.44 ± 0.23 L · min-1 · m-2 sous pression positive en respiration spontanée (CPAP) de 5 cm. H2O s’est élevé à 3.73 ± 0.15 L · min-1 · m-2 post-extubation avec une augmentation significative du volume ďéjection. La fréquence cardiaque et les pressions artérielles
moyennes et capillaires pulmonaires n’ont pas changé. Ainsi ľaugmentation de la consommation ďoxygène du myocarde de 8.52
± 0.55 à 8.85 ± 0.93 ml · min-1 et celle du flot coronarien de 172 ± 18 à 179 ± 17 ml · min-1 ont été moindres que celles, importantes, déjà observées lors de ľintubation. On a noté chez deux patients une production
de lactate par le myocarde, sans changement de ľhémodynamic systémique et coronarienne non plus que de signe clinique ou électrocardiographique
ďischémie. Donc, après un pontage coronarien, ľextubation ne semble pas causer ďeffet néfaste sur les circulations systémique
et coronarienne, toutefois, le myocarde revascularisé peut demeurer sensible au métabolisme anaérobique. 相似文献
3.
A. G. Dupont 《European journal of clinical pharmacology》1990,38(Z2):S96-S100
A randomized, double-blind, placebo-controlled study was conducted to study the effects of acute and chronic administration of carvedilol in essential hypertension, with special emphasis on renal haemodynamics and function. Acute administration of a single dose of 50 mg carvedilol reduced systolic and diastolic blood pressure without inducing reflex tachycardia. Renal blood flow was preserved; accordingly, renal vascular resistance was significantly reduced. A significant reduction in the glomerular filtration rate and filtration fraction was observed. Plasma renin activity (PRA) and plasma aldosterone values were not changed. Chronic carvedilol treatment produced a significant fall in systolic and diastolic blood pressure, heart rate, PRA and plasma aldosterone. Renal blood flow, glomerular filtration rate and filtration fraction also remained unchanged; renal vascular resistance decreased significantly. It is concluded that carvedilol possesses definite antihypertensive and renal vasodilating properties, both acutely and after chronic treatment. 相似文献
4.
David L. Mattson Shanhong Lu Allen W Cowley Jr 《Clinical and experimental pharmacology & physiology》1997,24(8):587-590
1. Nitric oxide (NO) has been implicated as an important controller in the short- and long-term regulation of arterial pressure. Studies performed in our laboratory have demonstrated that chronic intravenous administration of the NO synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) selectively decreases renal medullary blood flow, causes sodium and water retention and leads to hypertension. 2. To determine the importance of the renal medullary effects in this model of hypertension, further studies were conducted to examine the influence of selective stimulation or inhibition of renal medullary NO on whole kidney function and cardiovascular homeostasis. With the use of a unique catheter to directly infuse into the renal medullary interstitial space, stimulation (bradykinin or acetylcholine) or inhibition (L-NAME) of renal medullary NO selectively increased or decreased renal medullary blood flow. 3. The changes in medullary flow in these experiments were associated with parallel changes in sodium and water excretion independent of alterations in renal cortical blood flow or glomerular filtration rate. 4. Studies were then undertaken to examine the long-term effects of selective NO inhibition in the renal medulla on cardiovascular homeostasis. Chronic infusion of L-NAME directly into the renal medullary interstitial space of uninephrectomized Sprague-Dawley rats led to a selective decrease in renal medullary blood flow that was sustained throughout the 5 day L-NAME infusion period. The decrease in medullary blood flow was associated with retention of sodium and the development of hypertension and the effects were reversible. 5. The data reviewed indicate that NO in the renal medulla has a powerful influence on fluid and electrolyte homeostasis and the control of blood pressure. 相似文献
5.
J. Boldt H. A. Adams B. Zickmann D. Kling G. Hempelmann 《European journal of clinical pharmacology》1990,38(5):431-436
Summary The release of endogenous catecholamines in aorto-coronary bypass graft patients receiving either 0.5 mg/kg enoximone (n=10), 4.0 mg/kg theophylline (n=10) or saline solution (control,n=10) has been studied, as well as certain haemodynamic parameters. Adrenaline (A) and noradrenaline (NA) concentrations were
not significantly changed by the administration of enoximone. Theophylline caused a small increase in NA (+ 40% in the 1st
min) and a marked increase in A (approximately + 7000% in the 1st min), which still remained elevated at the end of the investigation
period (+ 220% in the 30th min). The major haemodynamic effects of enoximone were a significant increase in cardiac index
(CI; + 35%) and a decrease in pulmonary capillary wedge pressure (PCWP; −27%), pulmonary artery pressure (PAP; −21%), RVEDV
and RVESV, while the heart rate (HR) remained almost unchanged. The dominant haemodynamic effects of theophylline were an
increase in HR (+ 26%; arrhythmia in 3 patients), PAP (+ 22%), and RVEDV (+ 19%), while REVESV (+ 26%), MAP (−16%), CI (−14%),
and RVEF (−15%) fell significantly.
It is concluded that the haemodynamic actions of enoximone are not mediated by catecholamine release, whereas the adverse
cardiovascular effects of theophylline might partly be explained by the significant increase in plasma adrenaline. 相似文献
6.
To detect early renal involvement in young diabetic patients (IDDM), urinary protein excretion and renal function were examined in 110 patients aged 5.9-25.0 years. Clearances of inulin and PAH were determined as well as albumin (Alb), IgG, N-acetyl-beta-D-glucosaminidase (NAG) and creatinine (Cr) excretion rates (UV). The patients were grouped according to IDDM duration (2- less than 5, 5-10 and greater than 10 years) and albumin excretion rate (non-albuminuria less than 20, microalbuminuria 20-200, and albuminuria greater than 200 micrograms/min per 1.73 m2). Four patients had overt albuminuria, 17 microalbuminuria (equally distributed among the duration groups). Grouped according to albumin excretion rate, the mean GFR was increased in those without albuminuria but 'normalized' in patients with microalbuminuria/albuminuria. Grouped according to albumin excretion rate and the duration of the disease, the non-albuminuric patients with IDDM for greater than 10 years had a lower GFR than those with a shorter duration of IDDM. The patients with microalbuminuria/albuminuria and IDDM for less than 5 years had a reduced GFR. Patients with increased NAG excretion rate had lower Na excretion rate, lower fractional Na excretion and greater creatinine excretion than those with normal NAG excretion. Albumin excretion correlated with IgG excretion, but also with NAG excretion. Our results suggest that early albuminuria in IDDM is of both glomerular and tubular origin. The hyperfiltration declines with increasing albumin excretion but also with the duration of the disease. 相似文献
7.
H. K. Iversen T. H. Nielsen K. Garre P. Tfelt-Hansen J. Olesen 《European journal of clinical pharmacology》1992,42(1):31-35
Summary The aim of the present study was to compare the ability of different doses of isosorbide-5-mononitrate (5-ISMN) to cause dilatation of medium sized and small arteries, and to examine the intensity and duration of any headache produced. Ten healthy volunteers each received 3 doses of 5-ISMN and placebo on separate days. The diameters of the radial and superficial temporal arteries were repeatedly measured with high frequency ultrasound and pain was scored using a 10 point verbal scale.A clear dose-relationship was found for plasma concentrations and headache, and for changes in the diameter of the temporal artery, but not for the radial artery.It is concluded that headache after 5-ISMN is caused by arterial dilatation or by mechanisms responsible for the arterial dilatation. Ultrasound monitoring of arterial diameters is an important and sensitive tool in the evaluation of nitrates and other vasodilators. 相似文献
8.
Gen Matsuo Yasuo Matsumura Kiyoshi Tadano Takashi Hashimoto Shiro Morimoto 《Clinical and experimental pharmacology & physiology》1997,24(7):487-491
1. The effects of sarafotoxin S6c (S6c), a selective endothelin ETB receptor agonist, on renal haemodynamics and urine formation were examined in anaesthetized dogs. 2. Intrarenal arterial infusion of S6c at a rate of 1 or 5 ng/kg per min produced a transient increase in renal blood flow (RBF), with no change in systemic blood pressure and heart rate; RBF then decreased gradually to below the basal value. There were significant and dose-dependent increases in urine flow and free water clearance and decreases in urine osmolality during S6c infusion, whereas urinary excretion of sodium and glomerular filtration rate (GFR) remained unchanged. Simultaneously, S6c administration elicited a marked increase in urinary excretion of nitric oxide (NO) metabolites, N02? and N03? (UNO*V). 3. In dogs simultaneously administered S6c (5 ng/kg per min) and iVG-nitro-L-arginine (NOARG; 40 (jig/kg per min), a NO synthase inhibitor, the renal vasodilator effect of S6c was abolished and marked reductions in RBF and GFR were observed. The S6c-induced diuretic action was not affected by NOARG. In the presence of NOARG, there was a small amount of UNOxV at the basal level and the administration of S6c did not increase UNOxV. 4. These results suggest that an intrarenal arterial infusion of S6c enhances the production of NO in the kidney and that this enhancement contributes to the peptide-induced renal vasodilation. In contrast, it is unlikely that S6c-induced water diuresis is related to NO production stimulated by this peptide. 相似文献
9.
PHILIPPE KIRSTETTER CHRISTOPHE PILETTE RICHARD MOREAU STEPHANE CAILMAIL VACLAV SAFKA THIERRY SOUPISON DIDIER LEBREC 《Journal of gastroenterology and hepatology》1996,11(3):230-235
The haemodynamic effects of nitrovasodilators and their mechanisms of action on portal hypertension remain unclear. The splanchnic and systemic haemodynamic response to the infusion of isosorbide dinitrate (100 μg/kg per min), a nitrovasodilator, was investigated in cirrhotic rats. The role of the conscious state in the haemodynamic response to isosorbide dinitrate was examined using rats that were anaesthetized with pentobarbitone. The role of sympathetic tone in the haemodynamic response to isosorbide dinitrate was examined using rats pretreated with the ganglion blocker hexamethonium. Isosorbide dinitrate had no haemodynamic effects in conscious, unblocked normal and cirrhotic rats. Isosorbide dinitrate had no haemodynamic effects in normal and cirrhotic rats treated with hexamethonium. In normal anaesthetized rats, isosorbide dinitrate significantly decreased systemic vascular resistance (414±25 vs 290±26 dyn.s/cm5 per 100 g). In cirrhotic anaesthetized rats, isosorbide dinitrate significantly decreased mean arterial pressure (98±6 vs 79±7 mmHg), systemic vascular resistance (318±30 vs 207±10 dyn.s/cm5 per 100 g), portal pressure (14.0±1.0 vs 11.3±0.9 mmHg) and portal territory vascular resistance (1362±163 vs 1031±182 dyn.s/cm5 per 100 g). In conclusion, this study shows that the portal hypotensive effects of isosorbide dinitrate depend upon the alterations of vascular tone by pentobarbitone. 相似文献
10.
Haemodynamic effects of DPI 201-106, following single intravenous dose administration to patients with moderate cardiac failure 总被引:1,自引:0,他引:1
HOGAN J. C.; GREENBAUM R. A.; LUNNON M. W.; HILSON A. J. W.; EVANS T. R. 《European heart journal》1988,9(5):498-502
DPI 201106 is a novel compound unrelated to other cardioactiveagents and has been shown to have an inotropic effect in animalpreparations. The drug was given by intravenous infusion (20mg over 10 min) to 10 patients with moderate cardiac failureand the haemodynamic effects measured at intervals up to 1 hfollowing infusion. Maximal effects were seen immediately followingthe infusion of DPI 201106. Cardiac index showed an increasefrom baseline 2·72 (0·16) 1 min-1 m-2 to 3·18(0.21) 1 min-1 m-2 at the end of infusion (P<0·001).Subsequent values were not significantly raised. Pulmonary capillarywedge pressure and pulmonary artery pressure fell from 27·6(3·2) and 36·9 (4·4) to 15·3 (3·6)and 24·2 (4·9) mmHg, respectively (P<0·001in both cases). A statistically significant effect on cardiacindex was not seen at 1 h. However, pulmonary pressures remainedreduced at this point. Radionuclide ejection fraction showeda significant increase from 15·4 (1·5) to 21·9(2·2)% (P<0·005) at the end of infusion, andmaintained a significant increase at 1 h. Having demonstratedbeneficial, acute haemodynamic effects in this study, furtherwork should be undertaken with DPI 201106 to investigatethe effect of chronic treatment in patients with cardiac failure. 相似文献