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At least 1,441 records · Page 80Linked to original sources
PubMed2005

[Effect of electroacupuncture on hemodynamics at peri-intratracheal intubation period under general anesthesia].

OBJECTIVE: To observe effect of electroacupuncture on hemodynamics at peri-intratracheal intubation period under general anesthesia. METHODS: Sixty cases at peri-intratracheal intubation period under general anesthesia were randomly divided into electroacupuncture group [Before anesthesia induction, electroacupuncture stimulation was given at Neiguan (PC 6), Hegu (LI 4), Quchi (LI 11), Shenmen (HT 7)], and control group, 30 cases in each group. All the patients in the two groups received intratracheal intubation with light-guide laryngoscopy under general anesthesia with midazolam, fentanyl, isopropyl, succinylcholine, etc.; changes of various indexes of hemodynamics were detected at anesthesia induction and different time points of the intubation. RESULTS: At the anesthesia induction, various indexes of hemodynamics in the electroacupuncture group were relatively stable, and decreased significantly in the control group (P < 0.01); during intratracheal intubation, the various indexes in the electroacupuncture group (P < 0.05) and in the control group (P < 0.01) increased significantly as compared with those before anesthesia induction; 5 min after intubation, the various indexes in both the two groups restored normal. CONCLUSION: Electroacupuncture at Neiguan (PC 6) and other points can stabilize changes of hemodynamics at the intratracheal intubation and increase safety of operation under anesthesia.

Acupuncture Analgesia↗
PubMedDate not supplied

Influence of simvastatin at high dose and nifedipine on hemodynamic parameters in rabbits.

Recent findings in vitro have shown that statins could reduce cardiomyocyte viability. The correlation between statin cardiotoxicity, assessed in vitro, and cardiac efficiency, investigated in vivo has not been estimated so far. The aim of the present experiment was to establish the impact of high-dose simvastatin on the hemodynamic parameters, especially on myocardium efficiency, after continuous infusion of dopamine. Moreover, hemodynamic interaction between simvastatin and nifedipine, metabolized by the same izoenzyme CYP3A4 was examined. The experiments were performed on twenty seven New Zealand white rabbits. The animals were divided into four groups receiving: 0.2% methylcellulose (MC) (control group), nifedipine, simvastatin or simvastatin + nifedipine, for 14 days (p.o.). The following hemodynamic parameters were estimated: cardiac output index (COI), heart rate (HR), systolic blood pressure (SBP), mean blood pressure (MBP), diastolic blood pressure (DBP) and total peripheral resistance index (TPRI). The registration of hemodynamic parameters was performed by Doppler method (Hugo Sachs Electronic Haemodyn). Dopamine did not cause a statistically significant increase in COI in rabbits receiving simvastatin alone or concomitantly with nifedipine. Nifedipine significantly lowered COI, BP and HR in rabbits if given simultaneously with simvastatin. In conclusion, administration of nifedipine may elicit detrimental impact on statin therapy, resulting in the worsening of cardiac performance. This may suggest another mechanism of drug-drug interaction than the one based on CYP3A4 inhibition.

Animals↗
PubMedDate not supplied

[Central hemodynamics and gas exchange in the victims of cranio-thoracic trauma].

Cranio-thoracic trauma is characterized by severity of the pathologic process, peculiarities of the diagnosis, and a high mortality rate. However, problems concerning the correlation of hemodynamic and gas exchange disorders in patients with cranio-thoracic trauma, according to the principal factor of the damage, have been insufficiently studied. The purpose of the research was to study the condition of gas exchange and hemodynamics in this category of patients. Fifty-three patients with cranio-thoracic trauma (32 with main pathology of the cranium and 21 with trauma of the chest) were studied. The changes of gas exchange and hemodynamics in the early posttraumatic period in patients with principal trauma of the skull were unstable in character and responded easily to adequate therapy. Coarse disorders of gas exchange and low values of the cardiac debit were characteristic of cranio-thoracic trauma in which damage to the chest was the leading factor. Stabilization of gas exchange disorders was postponed in time, the hemodynamic parameters were stabilized by the end of the second day.

Acid-Base Equilibrium↗
PubMed2006

Relationship between pre-TIPS hepatic hemodynamics and postoperative incidence of hepatic encephalopathy.

BACKGROUND: Hepatic encephalopathy (HE) is one of the complications that have limited the effectiveness of transjugular intrahepatic portosystemic shunt (TIPS) most significantly. Up to the present, the predicting factors of HE post-TIPS have been debated controversially. This study was undertaken to verify the relationship between pre-TIPS intrahepatic hemodynamics and the incidence of post-TIPS HE. METHODS: The hepatic blood dynamics was evaluated in 41 patients with liver cirrhosis before TIPS and at one month after TIPS by ultrasonography. The patients were divided into two groups according to Doppler findings before TIPS: group 1, patients with prograde portal flow, and group 2, patients with hepatofugal or back-forth portal flow. The clinical characteristics (age, sex, etiology of liver disease, pre-TIPS Child-Pugh score, incidence of pre-TIPS HE, and portacaval pressure gradient), incidence of post TIPS HE, and pre-/post-TIPS hepatic arterial resistant index (RI) in the two groups were compared. The independent prognostic value of pre-TIPS variables for the onset of HE after TIPS, including age, Child-Pugh score, presence of HE before TIPS, and the pattern of portal flow, was tested with a multiple-factor regression analysis. RESULTS: No significant difference in age, etiology of liver disease, indications of TIPS placement, incidence of HE before TIPS, and portacaval gradient before and after TIPS was observed between the two groups; but liver failure was more severe in group 2 (P<0.05). The incidence of post-TIPS HE in group 2 was significantly lower than that in group 1 (P<0.01). Pre-TIPS, the RI of the hepatic artery in group 1 was significantly higher than that in group 2 (P<0.01). However, TIPS induced a significantly decreased RI in group 1 (P<0.01), but not in group 2. Multiple-factor regression analysis demonstrated that the pattern of portal flow before TIPS was closely associated with the onset of post TIPS HE. CONCLUSIONS: Pre-TIPS intrahepatic hemodynamics is closely related to the incidence of post-TIPS HE. Hepatic hemodynamics of patients with hepatofugal portal blood flow only changes a little after TIPS and still provides compensatory blood supply of the hepatic artery, and the hepatic function is less affected. Hence HE is unlikely. Hepatic hemodynamics of patients with prograde portal blood flow changes a lot after TIPS, and dual blood supply of the portal vein and hepatic artery changes into compensatory blood supply of the hepatic artery, and hepatic function suffers greatly in a short time. Thus HE is mostly likely.

Aged↗
PubMedDate not supplied

Non-invasive monitoring of cardiac hemodynamic parameters in doxorubicin-treated patients: comparison with echocardiography.

Cardiotoxicity represents the major factor that limits the use of anthracyclines in long-term cancer chemotherapy, therefore, the early detection of cardiac dysfunction is very important. Currently, the left ventricular ejection fraction is routinely used to screen cardiotoxicity. The most common methods in use are represented by 2-dimensional (2D) echocardiography and radionuclide angiography. The aim of the present investigation was to compare the findings obtained in patients subjected to doxorubicin (DXR) chemotherapy, by 2D echocardiography with hemodynamic parameters, resulting from a new non-invasive method based on an inert gas rebreathing technique. The study was conducted in 35 adult female patients (mean age 48 years, range 30-67) submitted to chemotherapy for metastatic breast cancer with DXR and paclitaxel. DXR was administered at a dose of 60 mg/m2 and paclitaxel at a dose of 200 mg/m2 every 3 weeks for a maximum of 8 cycles. Heart function evaluation was performed before initiating chemotherapy, after 3 cycles, 1 month after the completion of chemotherapy and when clinically requested. The mean cumulative dose of DXR, in patients who had received at least 4 or more cycles, was 320 mg/m2 of body surface area with a range of 240 to 480 mg/m2. The data obtained with 2D echocardiography (left ventricular end diastolic and systolic dimensions and ejection fraction) were compared with hemodynamic parameters obtained by the inert gas rebreathing technique (cardiac output, stroke volume, cardiac index and stroke index). Hemodynamic monitoring showed a progressive decrease of all parameters during DXR treatment, which became statistically significant at the end of the treatment. A significant reduction of ejection fraction due to an increase in the end systolic dimension of the left ventricle, without significant modification of the end diastolic dimensions, was observed. A good correlation was found between data obtained with the echocardiographic method and those obtained by the inert gas rebreathing technique. Two patients showed symptoms of congestive heart failure, the deterioration of cardiac function was simultaneously detected by both methods. These data confirm that cardiac function deterioration is detectable at a cumulative dose lower than 550 mg/m2 and that the inert gas rebreathing method for the determination of hemodynamic parameters could represent an alternative tool, in addition to conventional echocardiographic examination, in the evaluation of anthracycline-induced cardiotoxicity.

Adult↗
PubMed2005

[Effects of epidural blockade on the indices of central hemodynamics in operations of the aortofemoral bifurcation shunting].

The aim of the investigation was to study the mechanisms of arterial hypotension in the development of epidural blockade and to work out differentiated correction of disorders of the central hemodynamics at the stage of surgical intervention depending on the initial state of the cardio-vascular system. Three main types of the preoperative state of the central hemodynamics indices were defined in patients after operation on the abdominal part of the aorta. To prevent hemodynamic shifts in response to epidural anesthesia it is necessary to carry on differential therapy depending on the type of the preoperative state of hemodynamics including dosed infusion therapy, and for the development of syndrome of low cardiac output an inotropic support with Dobutamin is to be used.

Anastomosis, Surgical↗
PubMed1991

[Ibopamine--acute hemodynamic, renal and neurohumoral effects].

Ibopamine (IP) is a novel dopamine analogue for which beneficial effects have been shown in chronic heart failure. Hemodynamic effects of the substance include an increase in cardiac output and a decrease in the peripheral resistance. Aside from these hemodynamic effects, changes in renal (increased diuresis) and neurohumoral parameters (decreased plasma renin activity, aldosterone, norepinephrine, increased ANF and cGMP) have been found. The renal effects may originate from three independent mechanisms: 1) direct impact of improved hemodynamic parameters on the renal perfusion; 2) the improved cardiac performance results in a reduction of compensatory hormonal adaptations, such as the activation of the renin-angiotensin-aldosterone-axis or the sympathetic system; 3) direct effects on the intrarenal hemodynamic and glomerular/tubular functions induced by stimulation of renal dopaminergic receptors. The continued decrease of the plasma renin activity by 35% results in a reduction of the plasma levels of angiotensin II and aldosterone. Additionally, an increase in plasma atrial natriuretic factor (ANF) and its second messenger cyclic guanosine monophosphate (cGMP) was observed after ibopamine, which could contribute to the diuretic action of the drug. These findings underline the importance of extrarenal effects of a drug in the treatment of heart failure, this may essentially contribute to the improvement of cardiac performance, independent of positive inotropy.

Cardiotonic Agents↗
PubMed2006

The effect of valsartan, an angiotensin II receptor antagonist, on portal and systemic hemodynamics and on renal function in liver cirrhosis.

AIM: The aim of the study was to assess the effects of valsartan, a new generation angiotensin II receptor antagonist, on portal and systemic hemodynamics and on renal function in cirrhosis. METHODS: Eighty patients with cirrhosis and portal hypertension were divided in two groups as follows: group I - 40 patients who received valsartan (Diovan) 80 mg /day for 7 days and group II - 40 patients who received placebo. All the patients had hemodynamic, endocrine and renal parameters measured on day 0 and 7. The following were assessed: creatinine clearance, lithium clearance, plasma renin activity, concentration of plasma aldosteron and sodium homeostasis. Hemodynamic effects were assessed sonographically by portal flow volume and velocity evaluation, and mean arterial blood pressure. RESULTS: Valsartan increased the portal blood flow and the portal velocity (p < 0.01). These changes occurred without any significant changes in blood pressure and renal function or the glomerular filtration rate, compared with controls (p > 0.05). Valsartan also reduced the concentration of plasma aldosteron (p < 0.01) and increased the urinary sodium excretion (p < 0.001). CONCLUSION: A one week treatment with valsartan in cirrhotic patients with portal hypertension determines an increase in natriuresis, which could be regarded as beneficial and changes in the portal hemodynamics which might be speculated to represent a reduction of portal resistance.

Adult↗
PubMed1991

Hemodynamic consequences of arrhythmias.

Hemodynamic effects during arrhythmias may be caused by underlying pathology (i.e., infarction) as well as disturbance of rate or conduction pattern. In all arrhythmias, compensatory mechanisms tend to restore normal hemodynamics, and with good left ventricular function this can be achieved despite wide disturbance of rhythm. Hemodynamic effects of ectopic beats can result in dramatic fall of stroke volume and reduction in cardiac output, which is greater for ventricular than for atrial ectopics. Prolonged tachycardias are also tolerated up to far higher rates (180/min) if they are atrial, not ventricular, in origin. Mean blood pressure is often maintained even when systolic pressure and cardiac output are reduced. Even in healthy young subjects it is possible for cardiac ischemia to be induced by excessive heart rates. Some of the most deleterious effects are produced by simultaneous atrial and ventricular contraction, which results in continued suppression of cardiac output, both during tachycardias and at normal heart rates. Such situations are often highly symptomatic. Few measurements are available during external chest compression, and these suggest only marginal improvement in hemodynamics, with low pressures and output.

Animals↗
PubMedDate not supplied

[Hemodynamic repercussion of epidural bupivacaine in thoracic injuries].

Systemic and pulmonary hemodynamic effects of 8 to 10 ml of 0.25% bupivacaine containing 1:200,000 adrenaline administered at the midthoracic level were prospectively assessed in 20 patients (aged 45 +/- 16 years) with thoracic trauma presenting 6 +/- 2 rib fractures and pulmonary contusion of different extent and radiologic density. The study was carried out at comparable evolving times, 24 h after trauma, during the second or third day of treatment, and when the hemodynamic stability of the patient was achieved. Hemodynamic measurements were performed before and 30 min after administration of the analgesic agent using a Swan-Ganz catheter. The results indicate that administration of moderate doses of epidural bupivacaine at the middle thoracic level in patients with normovolemic thoracic traumatism were not followed by alterations in the hemodynamic function except for a slight decrease in systemic arterial and pulmonary pressure. The mean arterial pressure decreased by 8% (p less than 0.05), the cardiac index showed a 4% reduction (p = 0.05), and the mean pulmonary pressure experienced a 14% decrease (p less than 0.05).

Adult↗
PubMed1991

[Hemodynamic response of patients with arterial hypertension to graded pedal isometric exercise after administration of vasodilators of different classes].

Graded isometric exercise (IE) testing was performed to study the effects of vasodilators from various classes on the hemodynamic response in 60 patients with mild and moderate essential hypertension (EH). Hemodynamic parameters were determined by rheography. Group I patients took captopril, 50 mg, Group II prazosin, 2 mg, and Group III nifedipine, 20 mg. Hemodynamic changes tended to deteriorate in patients with the EH syndrome during IET. Application of the vasodilators led to the alleviation of the changes both at rest and during IET, as manifested by lower absolute values of the parameters and their relative increase. The beneficial influences of drugs from various classes on some hemodynamic parameters were different.

Adult↗
PubMed1991

[Hemodynamic and psychophysiologic evaluation in hypertensive diabetic patients].

In order to evaluate a peculiar hemodynamic and psychophysiological reactivity in hypertensive-diabetics, a male population of mild essential hypertensives and mild NID hypertensive-diabetics underwent a session of tests:Arithmetic, Sacks', Cold Pressor, Hand-grip, preceded and followed by a 10' recovery period, Valsalva Manoeuver, Beat to beat, Tilt table. Along the entire session, by means of a beat to beat, non invasive computerized system, we measured some pressure, hemodynamic, and extra-cardiovascular variables. The obtained findings seem to suggest a sympathetic hyperreactivity both in HD and in H. In HD it has a particular "tropism" for peripheral vascular bed, as showed by vascular resistances and peripheral temperature responsivity; on the other hand the cardiac contractility index is more depressed than in H, suggesting that in HD, cardiac and pressor responses might be influenced by some mechanisms whose nature seem related to neither functional damage nor hemodynamic adjustments. The different profiles of the two populations seem to confirm the utility of this kind of hemodynamic, non invasive evaluation in all the pathologies where Autonomic Nervous System is involved, in order to obtain a better diagnosis approach and therapeutic treatment.

Body Temperature↗
PubMed1991

[Invasive hemodynamic assessment and interventional therapy].

Cardiovascular diseases are the main reason for hospitalization and usually followed by a conservative therapeutic approach. Due to the improvement over the last few years in the results of surgery in the elderly, the number of hemodynamic studies has increased. Hemodynamic studies are generally performed in elderly patients with symptomatic valvular heart disease and acute myocardial infarction with complications. The incidence of complications in the elderly during catheterization and coronarography is higher than in younger but still low. Cardiovascular hemodynamics in the elderly is determined by a combination of lifestyle, the presence of cardiac diseases that increase in prevalence with advancing age (e.g., coronary artery disease) and age-related changes in cardiovascular hemodynamic per se. With age, the tunica media of major blood vessels stiffens. This produces a elevation of systolic blood pressure (afterload) in many elderly patients which in turn increases left ventricular (LV) wall stress and results in mild compensatory LV hypertrophy. This compensatory hypertrophy normalizes wall stress, but produces pertubations in diastolic function such as: a reduction in the rate of both diastolic and LV peak filling, a diminished diastolic compliance associated with LV hypertrophy and a greater dependence upon left atrial contraction to maintain cardiac output. Recently the proportion of these patients who have percutaneous transluminal coronary angioplasty (PTCA) is growing. PTCA can be performed with a high rate of clinical success. Complete revascularization is low, particularly in patients with trivessel disease. The most common reasons for incomplete revascularization were: vessels with chronic total occlusion and vessels with diffuse disease. The rate of major cardiac complications was high among patients at high-risk in the presence of trivessel disease and low left ejection fraction. Long-term results were encouraging. For 90% of patients who had clinical success after PTCA, the end results continued to be beneficial. In conclusion, PTCA is a valid therapeutic alternative in elderly patients with coronary artery disease. In subsets of patients with single and bivessel disease, the short- and long-term outcome is very favourable. In patients with triple vessel disease, early clinical success rate is low but the long-term success rate is, however, acceptable.

Aged↗
PubMed1991

[Hemodynamic assessment after heart transplantation].

OBJECTIVE: Comparative analysis of the results of the hemodynamic evaluations performed at the preoperative period, during the first week and at the end of the first and second years, after orthotopic heart transplantation. DESIGN: Retrospective study of hemodynamic evaluation of patients submitted to orthotopic cardiac transplantation from April 1987 to April 1990. SETTING: Transplanted patients admitted at the cardiology and cardio-toracic surgery departments of the Hospital Santa Marta. PATIENTS: 15 patients (eleven males and four females) aged 21 to 55 years (mean = 33.3 +/- 10.5), with the preoperative diagnosis: dilated cardiomyopathy in 11, ischemic heart disease in three and hypertrophic cardiomyopathy in one patient. All the patients were on triple immunosuppressive therapy (cyclosporine A, azatioprine and prednisolone) at the time of the first week evaluation. Three of the eight patients evaluated at the end of the first year were with double immunosuppressive regimen (without steroids), seven at NYHA functional class I and one patient at class II. The three patients evaluated at the end of the second year were on triple immunosuppressive regimen and in class I. INTERVENTIONS: We considered, preoperatively (PrOp), at the first week (1W), and at the end of the first (1Y) and second (2Y) years: mean right atrial pressure (RA), systolic pulmonary arterial pressure (PAs), mean pulmonary arterial pressure (PAm), pulmonary capillary wedge pressure (PCW), mean systemic arterial pressure (SAm), cardiac index (CI), pulmonary vascular resistance (PVR) and systemic vascular resistance (SVR). At 1Y and 2y there were also considered the left ventricular end-diastolic pressure (LVEDP) and the ejection fraction (Ej). RESULTS: (table; see text) The results found at 2Y were similar to those showed at 1Y. At 1Y and 2Y LVEDP and Ej were normal. CONCLUSIONS: A high prevalence of mild to moderate hemodynamic disturbances characterizes the early post-operative period in cardiac transplantation. Abnormal pressures on right atrium, pulmonary artery, pulmonary capillary wedge pressure, are found on a significant number of patients, and pulmonary and systemic vascular resistances are also elevated. However at the end of the first year there is a significant improvement compared with the first week. Normality is the hallmark of hemodynamic evaluation performed in transplant recipients at the end of the first and second years.

Heart Transplantation↗
PubMed1991

[Pulmonary hemodynamics in patients with hypertension during acute drug tests using obsidan and corinfar].

Two-dimensional and Doppler echocardiographies were used to examine 102 hypertensive patients who were found to have pulmonary hypertension, whose manifestation was determined by the degree of arterial hypertension, cardiac contractile insufficiency and diminished left heart pump function. The degree of pulmonary hypertension was related to the hemodynamic type and maximal with hypokinetic circulation when the pump function of the heart was minimal. Obsidan caused a decrease in pulmonary and systemic arterial hypertension, producing higher effects with hypokinetic hemodynamics. Corinfar was demonstrated to attenuate pulmonary hypertension to a greater extent. Its action on systemic arterial hypertension was highest in patients with hyperkinetic circulation. Heterodirectional hemodynamic effects of these drugs make it expedient to study their combined action on the hemodynamic of hypertensive patients.

Adult↗
PubMed1991

[Hemodynamic changes in patients with myocardial infarct complicated by acute left ventricular failure during combined nitroglycerin and dobutamine therapy].

A total of 18 patients with acute myocardial infarction complicated by acute left ventricular failure were examined for their central hemodynamics. Intravenous nitroglycerin was shown to cause positive changes in central hemodynamic parameters, but it failed to normalize the hemodynamics in patients with baseline low blood pressure, as nitroglycerin induced a further reduction in blood pressure. A combined administration of nitroglycerin and dobutamine solutions contributes to hemodynamic normalization and is indicated for patients with acute myocardial infarction complicated by acute left ventricular failure at a baseline low blood pressure.

Aged↗
PubMedDate not supplied

Hemodynamic response to OKT3 in orthotopic heart transplant recipients: evidence for reversible myocardial dysfunction.

The murine-derived monoclonal antibody OKT3 has been shown to be a useful immunosuppressive agent in transplant recipients; but it may cause cardiac instability and hemodynamic findings similar to those seen in septic shock after a first dose. Eight patients who received orthotopic heart transplants and were randomized to OKT3 therapy for immunosuppression were evaluated with serial hemodynamic and radionuclide monitoring for an 8-hour period during the first dose of OKT3. Cytokines including tumor necrosis factor-alpha, interleukin-1 and -2, and interferon-gamma were measured hourly to determine the potential mechanism of action of OKT3. All patients tolerated OKT3, although most had symptoms--pyrexia, chills, dyspnea, nausea and vomiting, and fever--within an hour after the dose. All patients exhibited a biphasic hemodynamic response to the first dose of OKT3. The initial hemodynamic response was characterized by a hyperdynamic phase with involvement in cardiac function as measured by cardiac output and ejection fraction. Left ventricular ejection fraction increased from 68% +/- 10% to 79 +/- 11% and was accompanied by increases in right ventricular ejection fraction and increases in cardiac index from 2.1 +/- 1.1 to 3.8 +/- 1.3 L/min/m2. The increase in ejection fraction was accompanied by a significant decrease in systemic vascular resistance index, from 2190 +/- 740 to 1608 +/- 573 dyne.sec.cm-5. The improvement in left ventricular ejection was caused by a significant decrease in end-systolic volume index (18 +/- 9.5 to 11 +/- 7 ml/m2). This occurred within the first 2 hours after OKT3 and was followed by cardiac index and ejection fraction returning to baseline in the next 2 to 3 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

[The hemodynamic effects of a treatment with beta-receptor blockers during coronary surgery. A comparison between acebutolol and esmolol].

UNLABELLED: Patients undergoing coronary artery bypass grafting are at risk for perioperative myocardial ischemia. Most such ischemic episodes occur without obvious hemodynamic changes. Tachycardia as a predictor for increased myocardial oxygen consumption doubles the incidence of myocardial ischemia when heart rate increases to over 110 beats/min. During the operative procedure for coronary revascularization, some maneuvers, e.g. intubation, sternotomy and mediastinal preparation, may be associated with tachycardia and increases in blood pressure despite an adequate level of anesthesia, so that the administration of beta-receptor blocking agents seems to be indicated. METHODS: The study included 20 patients undergoing elective aortocoronary bypass grafting. All patients developed tachycardia (heart rate greater than 100 beats/min) before the start of extracorporeal circulation. The hemodynamic effects of 0.1 mg/kg acebutolol given i.v. as a bolus over 30 s and hemodynamic effects of the ultrashort-acting esmolol by continuous infusion (loading dose 500 micrograms/kg over 1 min followed by a dose of 100 micrograms/kg per min) were randomly investigated. Anesthesia was maintained with fentanyl, midazolam and pancuronium bromide. All patients were invasively monitored by means of a pulmonary artery catheter. In addition, left ventricular pressure (LVP), left ventricular end diastolic pressure (LVEDP) and dp/dtmax were measured. RESULTS: Both acebutolol and esmolol, decreased the heart rate significantly (-24%, -27.5%), while the mean arterial pressure remained nearly unchanged. The cardiac index was diminished following acebutolol (-15.4%) and esmolol (-27.4%), while no significant change in stroke volume index was observed; systemic vascular resistance rose in all patients. Pulmonary artery pressure, PCP, PRA, LVP and LVEDP were unchanged, whereas dp/dtmax decreased both with acebutolol (-23.5%) and with esmolol (-36.5%). CONCLUSION: Both beta-receptor blockers--acebutolol and the ultrashort-acting esmolol--diminish heart rate sufficiently when tachycardia occurs during coronary artery bypass grafting. Reduction of heart rate is associated with a decrease of cardiac output and an impairment of myocardial contractility. From the hemodynamic point of view there is no major difference between the two beta-receptor blockers investigated, but esmolol may have an advantage over acebutolol because of its short elimination half-life.

Acebutolol↗