Significant Reduction In Cardiac Index Research Articles

Outcome of the Development of Early Restrictive Physiology after Heart Transplantation

<h3>Purpose</h3> Cardiac allograft vasculopathy (CAV) is one of the major factors limiting long-term survival. A severe form of CAV is small vessel disease which results in restrictive cardiac physiology (RCP). This RCP causes a very stiff heart which leads to significant reduction in cardiac index and elevation of cardiac pressures. The pathophysiology behind this RCP is most likely due to small vessel CAV with scarring and fibrosis. The outcome of patients with this RCP has not been well established. <h3>Methods</h3> Between 2010 and 2017 we assessed 23 heart transplant patients who developed RCP defined by right atrial pressure ≥ 15 mmHg, pulmonary artery diastolic pressure ≥ 15 mmHg, pulmonary capillary wedge ≥ 15 mmHg, and cardiac index ≤ 2.2 mm. Subsequent outcomes after diagnosis of RCP were 3-year survival, freedom from CAV (angiographic stenosis>30%), non-fatal major adverse cardiac events (NF-MACE: MI, new CHF, PCI, ICD implant, stroke), development of donor-specific antibodies (DSA) and re-hospitalizations. 1-year freedom from acute cellular rejection (ACR) was also assessed as risk factors for the development of RCP. The study group was compared with a case-controlled group 2:1 matched by age, gender, and era. <h3>Results</h3> The average time from transplant to the diagnosis of RCP was 1.5 ± 1.4 years. The RCP group compared to control had significantly lower subsequent 3-year survival, 3-year freedom from CAV, NF-MACE and hospitalizations. There was also a lower freedom from 1-year cellular rejection episodes and DSA in the RCP group compared to control. (See table) <h3>Conclusion</h3> Heart transplant patients who develop early RCP appear to have significantly reduced survival. ACR and DSA are associated with the development of RCP. As these patients do not appear to have a reversible cause, appropriate patients may be assessed for re-transplantation.

Влияние экспериментальной гиперкальциемии на кардиоваскулярные проявления хронической медной интоксикации

Chronic toxicity of copper sulfate leads to the formation of system hemodynamic disturbances, which manifests itself in the form of increased mean arterial pressure in experimental animals and reduction in the pumping function of the heart. Increased heart rate in experimental animals under conditions of chronic copper toxicity is compensatory in nature and is intended to maintain the level of cardiac output. The observed increase adrenal reactivity of cardiovascular system in animals receiving only insulated copper sulfate, apparently due to changes in the activity of sympathetic nervous system. Under the conditions of experimental hypercalcemia toxic effects of copper on the cardiovascular system become more pronounced, probably due to an increase in the absorption of the metal in gastrointestinal tract. Copper sulphate amid intragastric administration of vitamin D3 leads to greater inhibition of the contractile function of the heart, as compared with the group of animals treated only xenobiotic. Despite a significant reduction in cardiac index, formed pronounced arterial hypertension associated with a strong increase of the specific peripheral vascular resistance. Effect of copper sulfate adrenal reactivity cardiovascular system is more pronounced in animals with experimental hypercalcemia model.

Ways of Improving the Results of Treatment for Pulmonary Thromboembolism

Objective: to reveal the predictors of clinically significant deterioration of cardiac pump function resulting from alveolar opening maneuver (AOM) (mobilization) made early after extracorporeal circulation during standard cardiosurgery. Subjects and methods. Hemodynamic, clinical, and laboratory parameters were analyzed in 20 cardiosurgical patients who had undergone AOM in the early postperfusion period. The study inclusion criteria were a PaO2/FiO2 ratio of less than 350 mm Hg, a cardiac index (CI) of more than 2.5 l/min/m2, a dosage of dopamine and/or dobutamine of not more than 10 ^g/kg/min, and standard AOM performance (Pmax, 30—35 cm H2O; end-expiratory pressure (PEEP), 13—15 cm H2O). Regression analysis was used to identify the predictors of a clinically significant reduction in CI (less than 2.5 l/min/m2). Results. Before and after AOM, CI was 3.1±0.1 and 2.9±0.1 l/min/m2, respectively (p&gt;0.05); however, CI was less than 2.5 l/min/m2 (2.16±0.09 l/min/m2) in 25% of cases. After AOM, CI values were significantly related to those recorded prior to a respiratory procedure (p=0.039), total peripheral vascular resistance index (TPVRI) (p=0.00039), and intrapulmonary blood shunt fraction (Qs/Qt) (p=0.041). There were no relationships to other recorded and estimated hemodynamic parameters (p&gt;0.1). &#8211; After AOM, CI values were unrelated (p&gt;0.1) to the duration of extracorporeal circulation, the period of myocardial ischemia, and the used dosages of inotropic agents. The predictor of a clinically significant CI reduction after AOM was the only index TPVRI (p=0.00025) recorded before a respiratory procedure. Following AOM, the probability of a significant CI reduction substantially increased (the approximation coefficient R2=0.75) at TPVRI values of 2000 din^sec^cm-5^m2 or more. Conclusion. After AOM performed in the early period after extracorporeal circulation, CI values are related to the baseline level of CI, TPVRI, and Qs/Qt; however, after this procedure only the value of TPVRI is a reliable predictor of clinically significantly depressed cardiac pump function. The risk of persistent car-diodepression is highest at TPVRI values of 2000 din^sec^cm-5^m2 or more. AOM should be carried out early after extra-corporeal circulation in cardiosurgical patients, by making an invasive monitoring that makes it possible to maximally correctly evaluate central hemodynamics, including CI and TPVRI. Key words: alveolar opening maneuver (mobilization), lung recruitment, recruiting maneuver in cardiosurgical patients, central hemodynamics during lung recruitment, cardiodepression during lung recruitment.

Predictors of the Cardiodepressive Effect of Alveolar Opening Maneuver (Mobilization) in Cardiosurgical Patients

Objective : to reveal the predictors of clinically significant deterioration of cardiac pump function resulting from alveolar opening maneuver (AOM) (mobilization) made early after extracorporeal circulation during standard cardiosurgery. Subjects and methods. Hemodynamic, clinical, and laboratory parameters were analyzed in 20 cardiosurgical patients who had undergone AOM in the early postperfusion period. The study inclusion criteria were a PaO 2 /FiO 2 ratio of less than 350 mm Hg, a cardiac index (CI) of more than 2.5 l/min/m 2 , a dosage of dopamine and/or dobutamine of not more than 10 μg/kg/min, and standard AOM performance (P max , 30—35 cm H 2 O; endexpiratory pressure (PEEP), 13—15 cm H 2 O). Regression analysis was used to identify the predictors of a clinically significant reduction in CI (less than 2.5 l/min/m 2 ). Results . Before and after AOM, CI was 3.1±0.1 and 2.9±0.1 l/min/m 2 , respectively ( p >0.05); however, CI was less than 2.5 l/min/m 2 (2.16±0.09 l/min/m 2 ) in 25% of cases. After AOM, CI values were significantly related to those recorded prior to a respiratory procedure ( p =0.039), total peripheral vascular resistance index (TPVRI) ( p =0.00039), and intrapulmonary blood shunt fraction (Qs/Qt) ( p =0.041). There were no relationships to other record ed and estimated hemodynamic parameters (p>0.1). After AOM, CI values were unrelated (p>0.1) to the duration of extracorporeal circulation, the period of myocardial ischemia, and the used dosages of inotropic agents. The predictor of a clinically significant CI reduction after AOM was the only index TPVRI (p=0.00025) recorded before a respiratory procedure. Following AOM, the probability of a significant CI reduction substantially increased (the approximation coefficient R2=0.75) at TPVRI values of 2000 din•sec•cm-5•m2 or more. Conclusion. After AOM performed in the early period after extracorporeal circulation, CI values are related to the baseline level of CI, TPVRI, and Qs/Qt; however, after this procedure only the value of TPVRI is a reliable predictor of clinically significantly depressed cardiac pump function. The risk of persistent cardiodepression is highest at TPVRI values of 2000 din•sec•cm-5•m2 or more. AOM should be carried out early after extracorporeal circulation in cardiosurgical patients, by making an invasive monitoring that makes it possible to maximally correctly evaluate central hemodynamics, including CI and TPVRI.

Early Restoration of Cocaine-Induced Splanchnic Hypoperfusion in Anesthetized Dogs

Although cardiovascular effects of cocaine have been well studied, little is known about its effects on splanchnic perfusion. We studied systemic and regional hemodynamic effects of acute cocaine intoxication in dogs under volatile anesthesia. Mechanically ventilated beagle dogs, randomized at 1.5% halothane (n = 7) or 2.25% sevoflurane (n = 7) anesthesia, received an intravenous bolus of cocaine (12 mg/kg over 5 min) followed by 0.22 mg/kg/min infusion over 30 min. They were observed for 60 min thereafter. Cardiac index (CI), heart rate (HR), mean arterial pressure (MAP), portal blood flow (PBF), gastric PCO2 (gas tonometry), blood gases, and lactate and cocaine levels were assessed. Cocaine bolus promoted significant reductions in CI (∼ 50%), HR (∼ 20%), MAP (∼ 20%), and PBF (∼ 50%), accompanied by increase in systemic and splanchnic oxygen extractions and in gastric mucosal–arterial PCO2 gradient. Those changes were maintained during cocaine infusion and returned to baseline values parallel to plasmatic cocaine clearance. Unlike other shock states, regional parameters, including gastric mucosal–arterial PCO2 gradient, were restored before systemic variables. A possible local vasodilatory effect of volatile agents could play a role in this phenomenon. Cocaine infusion in anesthetized animals promoted marked systemic and regional hemodynamic derangement, which was rapidly reversible with decay of cocaine plasmatic concentration.

Pre- and postoperative systemic hemodynamic evaluation in patients subjected to esophagogastric devascularization plus splenectomy and distal splenorenal shunt: A comparative study in schistomomal portal hypertension

To investigate the systemic hemodynamic effects of two surgical procedures largely employed for treatment of schistosomal portal hypertension. Thirty-six patients undergoing elective surgical treatment of portal hypertension due to hepatosplenic mansonic schistosomiasis were prospectively evaluated. All patients were subjected to preoperative pulmonary artery catheterization; 17 were submitted to esophagogastric devascularization and splenectomy (EGDS) and 19 to distal splenorenal shunt (DSRS). The systemic hemodynamic assessment was repeated 4 d after the surgical procedure. Preoperative evaluation revealed (mean +/- SD) an increased cardiac index (4.78 +/- 1.13 L/min per m(2)), associated with a reduction in systemic vascular resistance index (1457 +/- 380.7 dynes.s/cm(5).m(2)). The mean pulmonary artery pressure (18 +/- 5.1 mmHg) as well as the right atrial pressure (7.9 +/- 2.5 mmHg) were increased, while the pulmonary vascular resistance index (133 +/- 62 dynes x s/cm(5) x m(2)) was decreased. Four days after EGDS, a significant reduction in cardiac index (3.80 +/- 0.4 L/min per m(2), P < 0.001) and increase in systemic vascular resistance index (1901.4 +/- 330.2 dynes x s/cm(5) x m(2), P < 0.001) toward normal levels were observed. There was also a significant reduction in pulmonary artery pressure (12.65 +/- 4.7 mmHg, P < 0.001) and no significant changes in the pulmonary vascular resistance index (141.6 +/- 102.9 dynes x s/cm(5) x m(2)). Four days after DSRS, a non-significant increase in cardiac index (5.2 +/- 0.76 L/min per m(2)) and systemic vascular resistance index (1389 +/- 311 dynes x s/cm(5) x m(2)) was observed. There was also a non-significant increase in pulmonary artery pressure (19.84 +/- 5.2 mmHg), right cardiac work index (1.38 +/- 0.4 kg x m/m(2)) and right ventricular systolic work index (16.3 +/- 6.3 g x m/m(2)), without significant changes in the pulmonary vascular resistance index (139.7 +/- 67.8 dynes xs/cm(5) x m(2)). The hyperdynamic circulatory state observed in mansonic schistosomiasis was corrected by EGDS, but was maintained in patients who underwent DSRS. Similarly, the elevated mean pulmonary artery pressure was corrected after EGDS and maintained after DSRS. EGDS seems to be the most physiologic surgery for patients with schistosomal portal hypertension.

Haemodynamic effects of the prone position: a comparison of propofol total intravenous and inhalation anaesthesia

The haemodynamic changes of the prone position were investigated in 40 ASA I-II patients undergoing lumbar spine surgery. Patients were randomly assigned, following propofol intravenous induction, to receive maintenance of anaesthesia using either isoflurane 1-1.2% in air or target controlled propofol 3 microg.ml(-1) infusion. Measurements of non-invasive blood pressure, heart rate and cardiac output were made in the supine position. The patient was then turned prone onto a Montreal pattern mattress and measurements repeated. Cardiac output measurements were made using a non-invasive cardiac output monitor. We found a significant reduction in cardiac index in both groups and a significantly greater change with propofol compared to isoflurane on turning supine to prone (CI change 0.4 vs 0.7 l.min(-1).m(-2) p = 0.001 and SVRI change 89 vs 177 dyne.s(-1).cm(-5), p = 0.041). We conclude that turning healthy patients prone produces a clinically significant reduction in cardiac output, the change being greater during maintenance of anaesthesia using propofol compared to isoflurane.

Cardiovascular effects of canrenone in patients with preascitic cirrhosis

In patients with cirrhosis and portal hypertension, standing induces a reduction in cardiac index (CI) and an increase in systemic vascular resistance index. Our previous studies indicate that this abnormal hemodynamic response to standing is due to an altered myocardial function, because cirrhotic patients are unable to compensate for the reduced preload with an increase in left ventricular (LV) ejection fraction (EF) and stroke volume. To evaluate whether the cardiac dysfunction in cirrhosis is influenced by canrenone, an aldosterone antagonist, 8 patients with preascitic, nonalcoholic cirrhosis, and portal hypertension underwent echocardiographic assessment of LV function and systemic hemodynamics and determinations of plasma volume, urinary sodium excretion, and plasma renin activity (PRA), aldosterone (PAC), and norepinephrine (PNE) when on a 150-mmol/d-sodium diet (baseline), after 1 month on canrenone (100 mg/d) plus a 40-mmol/d-sodium diet and after 1 month on canrenone plus a 150-mmol/d-sodium diet. Echocardiographic evaluation was performed with the patient in the supine position and during active standing. At baseline, patients had high plasma volume and normal renal function, PRA, PAC, and PNE. CI, LVEF, and stroke volume index were also normal. Standing caused a significant reduction in CI and LVEF. After canrenone and either sodium diet, CI significantly decreased, and PRA and PNE increased in the supine position. On standing, LVEF and CI did not decrease further. Plasma volume significantly decreased only after low-sodium diet plus canrenone. In conclusion, canrenone normalizes the cardiac response to the postural challenge in patients with preascitic cirrhosis. (H EPATOLOGY 2002;35:1441-1448.)

Total versus selective hepatic vascular exclusion in major liver resections

Background: Total hepatic vascular exclusion (THVE) and selective hepatic vascular exclusion (SHVE) are two effective techniques for bleeding control in major hepatic resections. Outcomes of the two procedures were compared. Methods: Patients undergoing major liver resection were randomly allocated to the THVE and SHVE groups. Intraoperative hemodynamic changes and the postoperative course of the two groups were compared. Results: During vascular clamping, the THVE group showed a significant elevation in pulmonary vascular resistance, systemic vascular resistance, intrapulmonary shunts, and a significant reduction in cardiac index, compared with the SHVE group ( P <0.05). Patients undergoing THVE received more crystalloids and blood, showed more severe liver, renal and pancreatic dysfunction, and had a longer hospital stay than the SHVE group ( P <0.05). Conclusions: Both techniques are equally effective in bleeding control in major liver resections. THVE is associated with cardiorespiratory and hemodynamic alterations and may be not tolerated by some patients. SHVE is well tolerated with fewer postoperative complications and shorter hospitalization time.

Non-blood contacting biventricular support for severe heart failure

Background. Direct mechanical ventricular actuation (DMVA) is a non-blood contacting method of biventricular support. DMVA employs a vacuum attached, pneumatically regulated, flexible membrane to transfer both systolic and diastolic forces to the ventricular myocardium. The purpose of this study was to determine if DMVA effectively restores pump performance when applied to the severely failing heart. Methods. Bovines (n = 10) underwent thoracotomy and were instrumented for continuous hemodynamic monitoring. Cardiac failure was induced by β 1-blockade to achieve a cardiac index of < 1.5 l/min/m 2 for 1 hour. Heart rate was maintained at 100 bpm by atrioventricular sequential pacing. Synchronous DMVA support was then applied for 3 hours. Results. Eight animals achieved significant reductions in cardiac index and mean arterial pressures (35%* and 43%* control, respectively; * p < 0.05). DMVA restored cardiac index to baseline and significantly increased arterial pressures ( p < 0.05; DMVA versus cardiac failure). Pulmonary flow and mean pulmonary artery pressures were similar to baseline during DMVA ( p = NS). Pathologic exam did not demonstrate evidence of significant device trauma. Conclusions. DMVA support can effectively restore pump performance of the acutely failing heart. Synchronization may be inherent to the stimulus of cardiac compression. These data further substantiate DMVA’s potential as an adjunct to the field of circulatory support.

The Influence of Phosphodiesterase Inhibitor, Rolipram, on Hemodynamics in Lipopolysaccharide-Treated Rats

Administration of bacterial endotoxin (lipopolysaccharide, LPS) intravenously has been noted to produce a shock state, which is characterized by hypotension and multi-organ system failure. The aim of the present investigation was to (a) examine the influence of rolipram on hemodynamics, plasma levels of tumor necrosis factor-alpha (TNF-alpha) levels, and production of inducible nitric oxide synthase (iNOS) in the lungs, ex vivo, in LPS-treated rats, and (b) determine the cardiovascular effects of a selective alpha1-adrenoceptor agonist, methoxamine, in the absence or presence of rolipram in rats treated with LPS. Blood pressure, cardiac index, heart rate and arterial resistance were assessed in Long-Evans rats anesthetized with thiobutabarbital. Administration of LPS to animals resulted in a significant reduction in cardiac index over time. The administration of LPS to rats resulted in a substantial rise in the plasma levels of TNF-alpha. Furthermore, the injection of LPS resulted in a significant increase in the iNOS activity in the lungs. Pre-treatment with rolipram prevented the decline in cardiac index in animals that received LPS. Infusion of methoxamine into animals injected with rolipram and pre-treated with LPS did not result in significant changes in cardiac index. Pre-treatment with rolipram or dexamethasone in animals injected with LPS significantly prevented the rise in TNF-alpha when compared to the respective values in vehicle-treated animals. Our present observations support the view that the cardiac index can be maintained in animals treated with LPS independent of iNOS inhibition.

Haemodynamic effects of the lateral decubitus position and the kidney rest lateral decubitus position during anaesthesia

We measured the haemodynamic effects of changing from the supine position to the lateral decubitus (lateral) position, and then to the kidney rest lateral decubitus (kidney) position in 12 patients undergoing nephrectomy under isoflurane anaesthesia. Eight control patients undergoing pulmonary surgery remained in the lateral position. The lateral position produced no significant changes. In the kidney position, however, significant reductions occurred in the mean arterial (P < 0.01), right atrial (P < 0.05) and pulmonary artery wedge pressures (P < 0.01). There were also significant reductions in cardiac index (from 3.04 (SD 0.21) to 2.44 (0.26) litre min-1 m-2, P < 0.01) and stroke volume index (from 40 (5) to 31 (5) ml beat-1 m-2, P < 0.01). The systemic vascular resistance index increased significantly (P < 0.05). Cardiac output was probably reduced by a decrease in venous return and an increase in systemic vascular resistance.

Transmyocardial laser revascularization: experimental studies in healthy porcine myocardium

Background. Clinical studies have demonstrated a significant reduction of cardiac index shortly after transmyocardial laser revascularization in patients with low ejection fraction. We analyzed the influence of transmyocardial laser revascularization on healthy myocardium in pigs. Methods. Carbon dioxide channels were created in 20 pigs which were observed for 6 hours. Ten pigs received one laser channel and ten pigs two laser channels per cm 2 in the left anterior descending artery region. Seven pigs served as controls. Perfusion (microspheres), function, histochemical, and histologic assessments were subsequently performed. Results. A significant deterioration of left ventricular stroke work index was observed shortly after transmyocardial laser revascularization in both laser groups ( p < 0.05). After 6 hours the left ventricular stroke work index did not increase and showed significantly reduced values at rest ( p < 0.05) and during stress in the laser groups ( p < 0.01). Normal regional perfusion, small ischemic and necrotic areas, open laser channels in the left anterior descending artery region and significantly increased myocardial water content were observed in the laser groups ( p < 0.01). Conclusions. Carbon dioxide laser channels significantly decrease global heart function shortly after transmyocardial laser revascularization in healthy porcine myocardium. This myocardial tissue showed no recovery 6 hours postoperatively.

Estrogen‐Dependent Hypotensive Effects of Ethanol in Conscious Female Rats

This study investigated the role of estrogen in the acute hemodynamic responses to intragastric (i.g.) ethanol in conscious female rats. Changes evoked by ethanol or equal volume of water in mean arterial pressure, heart rate, cardiac index, stroke volume (SV), and total peripheral resistance were followed in sham-operated, ovariectomy (OVX) vehicle-treated (OVX-veh), and OVX 17beta-estradiol (E2)-treated (OVX-E2) Sprague-Dawley rats. Plasma norepinephrine (NE) was measured as an index of sympathetic activity. In sham-operated rats, ethanol caused significant decreases in mean arterial pressure that were associated with significant reductions in cardiac index and SV, whereas total peripheral resistance was not changed. Measured plasma NE levels were not affected by ethanol except for a significant reduction observed one time. OVX abolished the hypotensive effect of ethanol and the associated decreases in cardiac output, SV, and plasma NE. Treatment of OVX rats with E2 restored the hypotensive and sympathoinhibitory (decreases in plasma NE) responses to ethanol. Blood ethanol concentrations were not affected by OVX or subsequent E2 administration. These findings suggest that intragastric ethanol elicits estrogen-dependent decreases in blood pressure in female rats, which results mainly from a reduction in cardiac output. The mechanism by which ethanol elicits E2-dependent hypotension remains to be determined.

Effects of adenosine a 2 a receptor agonist, cgs 21680, on blood pressure, cardiac index and arterial conductance in anaesthetized rats

The effects of 2- p-(2-carboxyethyl)phenethylamino-5′- N-ethylcarboxamidoadenosine (CGS 21680) on blood pressure, total peripheral resistance, cardiac index, heart rate and arterial conductance in different vascular beds in the presence and absence of hexamethonium (ganglionic blocker) and phenylephrine ( α 1-adrenoceptor agonist) were investigated in pentobarbitone-anaesthetized rats using a radioactive microsphere technique. CGS 21680 (0.1, 0.3 and 1.0 μg/kg/min) significantly decreased blood pressure and total peripheral resistance, and increased heart rate and cardiac index. In addition, after infusion with CGS 21680 (0.1, 0.3 and 1.0 μg/kg/min) arterial conductance in coronary bed significantly increased. However, while CGS 21680 (0.3 and 1.0 μg/kg/min) significantly increased conductance in skeletal muscle, it significantly decreased splenic arterial conductance. Moreover, CGS 21680 (1.0 μg/kg/min) significantly increased conductance in cerebral arterial bed. Infusion with hexamethonium (200 μg/kg/min) resulted in significant reduction in blood pressure, heart rate and cardiac index whereas stroke volume and total peripheral resistance remained unchanged. In animals that were pretreated with hexamethonium (200 μg/kg/min), further administration of CGS 21680 (0.3 μg/kg/min), compared to CGS 21680 alone, significantly reduced blood pressure, heart rate and cardiac index but did not affect total peripheral resistance or conductance in any vascular bed. Administration of phenylephrine (7 μg/kg/min) resulted in a significant increase in blood pressure and total peripheral resistance, and a significant reduction in cardiac index and heart rate. In animals infused with phenylephrine and CGS 21680 combined, in comparison to those animals that received CGS 21680 alone, no significant differences in blood pressure, heart rate, total peripheral resistance, cardiac index or conductance in any vascular beds were found. Our present findings suggest that CGS 21680 decreased blood pressure by decreasing total peripheral resistance, and increased cardiac index possibly through a reflex-mediated increase in heart rate. Moreover the coronary arterial bed is the most sensitive and cerebral arterial bed is the least sensitive to the effects of CGS 21680. In addition, the autonomic nervous system did not appear to play a major role in the actions of CGS 21680 on arterial conductance, and there was no difference in the action of this compound in the states of normal and raised vascular tone.

Beneficial effects of intravenous albumin infusion on the hemodynamic and humoral changes after total paracentesis

The study investigated the hemodynamic and neurohumoral effects of albumin infusion after total paracentesis in 18 patients with cirrhosis and tense ascites. Measurements of systemic and splanchnic hemodynamics, and vasoactive neurohumoral systems were performed before and immediately after total paracentesis. The patients were then randomized to receive albumin or not, and hemodynamic and humoral measurements were repeated at 24 hours. Hemodynamic and humoral changes just after paracentesis were similar in patients later randomized to receive albumin infusion or not. Twenty-four hours after total paracentesis, patients not receiving albumin had significant reductions in cardiac index (−13%; P = .005), femoral blood flow (−17%; P = .004), and pulmonary capillary pressure (−16%; P = .02), which were accompanied by significant increases in plasma renin activity (PRA) and plasma aldosterone (PA) and by significant decreases in atrial natriuretic factor (ANF) and plasma sodium. By contrast, there were no significant changes in patients receiving albumin, except for an increase in ANF and a further decrease in PA. In both groups, hepatic venous pressure gradient (HVPG) and azygos blood flow decreased just after paracentesis returning to baseline at 24 hours. This study shows that albumin infusion prevents the impairment in systemic hemodynamics, vasoactive neurohumoral systems, and plasma sodium after a large-volume paracentesis, without detrimental effects on portal pressure and portocollateral blood flow.

Beneficial effects of intravenous albumin infusion on the hemodynamic and humoral changes after total paracentesis

The study investigated the hemodynamic and neurohumoral effects of albumin infusion after total paracentesis in 18 patients with cirrhosis and tense ascites. Measurements of systemic and splanchnic hemodynamics, and vasoactive neurohumoral systems were performed before and immediately after total paracentesis. The patients were then randomized to receive albumin or not, and hemodynamic and humoral measurements were repeated at 24 hours. Hemodynamic and humoral changes just after paracentesis were similar in patients later randomized to receive albumin infusion or not. Twenty-four hours after total paracentesis, patients nor receiving albumin had total significant reductions in cardiac index (-13%; P = .005), femoral blood flow (-17%; P = .004), and pulmonary capillary pressure (-16%; P = .02), which were accompanied by significant increases in plasma renin activity (PRA) and plasma aldosterone (PA) and by significant decreases in atrial natriuretic factor (ANF) and plasma sodium. By contrast, there was no significant changes in patients receiving albumin, except for an increase in ANF and a further decrease in PA. In both groups, hepatic venous pressure gradient (HVPG) and azygos blood flow decreased just after paracentesis returning to baseline at 24 hours. This study shows that albumin infusion prevents the impairment in systemic hemodynamics, vasoactive neurohumoral systems, and plasma sodium after a large-volume paracentesis, without detrimental effects on portal pressure and portocollateral blood flow.

Haemodynamic effects of the position chosen for the insertion of an epidural catheter

An epidural catheter may be inserted with the patient either in the flexed left lateral or the sitting position. We have studied, non-invasively, the haemodynamic changes associated with these positions, using the thoracic bio-impedance method (BOMED NCCOM3 Monitor). Maternal arterial pressure and fetal heart rate were monitored simultaneously. Twenty healthy pregnant patients at term and 20 non-pregnant healthy controls, matched for age and height, were studied. The pregnant patients were scheduled for elective caesarean section and had singleton healthy fetuses. A significant reduction in stroke index (SI) occurred when the pregnant patients were repositioned from supine 15° wedged position to either flexed left lateral ( P < 0.01) or sitting positions ( P < 0.05). Similar reductions in SI with positioning were observed in the non-pregnant patients: flexed left lateral ( P < 0.01); and sitting ( P < 0.01). These changes in SI produced significant reductions in cardiac index (CI) in both groups. In the pregnant patients the CI was significantly lower in the flexed left lateral than in the sitting position ( P < 0.01). Consequently maternal systolic blood pressure was lower in the flexed left lateral position ( P < 0.01).

Hemodynamic changes due to intraoperative testing of the automatic implantable cardioverter defibrillator: Implications for anesthesia management

During the insertion of an automatic implantable cardioverter defibrillator, repeated induction of ventricular tachycardia or ventricular fibrillation and subsequent defibrillation is performed to determine the defibrillation threshold. In this study, the influence of these testing episodes on myocardial function was investigated in 13 patients under general anesthesia. Preoperative ejection fraction (EF) was 41 (14 to 84)% (median and range). Testing was performed 3 (2–5) times. During these testing episodes the patients received a total of 4 (2–8) countershocks. Patients with a preoperative EF < 30% (N = 5) showed a significant reduction of cardiac index (CI) from 2.2 (1.5-3.3) L/min/m 2 before testing to 1.5 (1.3-2.3) L/min/m 2 after the last testing episode, and of left ventricular stroke work index (LVSWI) from 32 (14–53) g · m/m 2 before testing to 22 (7–43) after the last testing episode. These changes were not related to the total fibrillation time or the cumulative defibrillation energy. Patients with a preoperative EF > 30% (N = 8) showed no significant changes of CI (2.15 [1.8-3.0] L/min/ m 2 v 2.15 [1.7-3.0] L/ min/ m 2) or LVSWI (35 [28–48] g · m/m 2 v 33.5 [27–52] g · m/m2). Comparison of the two patient groups revealed similar hemodynamic baseline values, but significant differences in LVSWI after the last testing episode. Defibrillation testing may produce a further reduction in myocardial performance in patients with preexisting poor cardiac function.

Evaluation of Right Ventricular Function During Aortic Operations

The simultaneous measurements of mixed venous oxygen saturation (SvO2) and right ventricular ejection fraction (RVEF) have now made it possible to precisely define and correlate the various hemodynamic changes that occur during abdominal aortic operations. Twenty-five patients undergoing infrarenal abdominal aortic aneurysm repair were examined with a pulmonary artery catheter capable of continuously measuring SvO2 and RVEF. With aortic clamping, significant reductions in cardiac index, stroke volume index, and right ventricular end-diastolic volume index (RVEDVI) were noted, while RVEF remained unchanged. Following unclamping of the aorta, a significant reduction in SvO2 occurred, accompanied by an increase in mean pulmonary artery pressure and in pulmonary vascular resistance. Despite the increase in afterload, RVEDVI and RVEF did not change after unclamping. These preliminary data suggest that right ventricular function is preserved during abdominal aortic aneurysm repair.