Effects of tilting on central hemodynamics and homeostatic mechanisms in cirrhosis

Serum catecholamines and dysautonomia in diabetic gastroparesis and liver cirrhosis

BACKGROUND

Plasma catecholamine influences autonomic function and control, but there are few reports correlating them. In this study, 47 individuals (mean age, 38 years) were studied: 19 diabetes mellitus (DM) patients with gastroparesis, 16 with liver disease and 12 control subjects.

METHODS

Noninvasive autonomic function was assessed for sympathetic adrenergic functions as peripheral vasoconstriction in response to cold stress test and postural adjustment ratio (PAR) and cholinergic function as Valsalva ratio, represented by change in R-R intervals. Measurements were compared by analysis of variance and Spearman's correlation, and results were reported as mean ± standard error.

RESULTS

Plasma norepinephrine (1902.7 ± 263.3; P = 0.001) and epinephrine (224.5 ± 66.5; P = 0.008) levels, as well as plasma dopamine levels (861.3 ± 381.7), and total plasma catecholamine levels were highest for patients with liver disease, who also had significant negative correlation between norepinephrine level and vasoconstriction (P = 0.01; r = -0.5), PAR1 (P = 0.01; r = -0.5), sympathetic adrenergic functions (P = 0.005; r = -0.6), total autonomic index (P = 0.01-0.5) and total autonomic function (P = 0.01; r = -0.2) and also negative correlation between epinephrine plasma level and total autonomic function (P = 0.04; r = 0.4). DM patients were next highest in norepinephrine level (133.26 ± 7.43), but lowest for plasma catecholamine; a positive correlation between dopamine level and PAR1 (P = 0.008; r = 0.6) was also seen in this group. Plasma dopamine levels and spider score correlated negatively (P = 0.04; r = -0.5) and total plasma catecholamine positively with encephalopathy (P = 0.04; r = 0.5) in patients with liver disease.

CONCLUSIONS

Plasma catecholamine levels correlated with adrenergic functions in control subjects and patients with DM and liver disease, with no significant correlation seen for cholinergic function.

Sympathetic withdrawal is associated with hypotension after hepatic reperfusion

OBJECTIVE

Post-reperfusion syndrome (PRS), severe hypotension after graft reperfusion during liver transplantation, is an adverse clinical event associated with poorer patient outcomes. The purpose of this study was to determine whether alterations in autonomic control in liver transplant recipients prior to graft reperfusion are associated with the subsequent development of PRS.

METHODS

Heart rate variability (HRV), systolic arterial blood pressure (SBP) variability, and baroreflex sensitivity of 218 liver transplant recipients were evaluated using 5 min of ECG and arterial blood pressure signals 10 min before graft reperfusion along with other clinical parameters. Logistic regression analyses were performed to assess predictors of PRS occurrence.

RESULTS

Seventy-seven patients (35 %) developed PRS while 141 did not. There were significant differences in SBP (110 ± 16 vs. 119 ± 16 mmHg, P < 0.001) and the ratio of low frequency power to high frequency power (LF/HF) of HRV (1.0 ± 1.4 vs. 2.1 ± 3.7, P = 0.003) between the PRS group and No-PRS group. In multivariate logistic regression analysis, predictors were LF/HF (odds ratio 0.817, P = 0.028) and SBP (odds ratio 0.966, P < 0.001).

INTERPRETATION

Low LF/HF and SBP measured before hepatic graft reperfusion were significantly correlated with subsequent PRS occurrence, suggesting that sympathovagal imbalance and depressed SBP may be key factors predisposing to reperfusion-related severe hypotension in liver transplant recipients.

Non invasive continuous hemodynamic evaluation of cirrhotic patients after postural challenge

AIM

To assess whether Most Care is able to detect the cardiovascular alterations in response to physiological stress (posture).

METHODS

Non invasive hemodynamic was assessed in 26 cirrhotic patients compared to healthy subjects, both in the supine and standing positions.

RESULTS

In baseline conditions, when compared to healthy subjects, cirrhotic patients showed significantly lower values of dicrotic and diastolic pressures and systemic vascular resistance. While in the standing position, cirrhotic patients showed higher values of cardiac index, stroke volume index and cardiac cycle efficiency. When returning to the supine position, cirrhotic patients exhibited lower values of dicrotic and diastolic pressures and systemic vascular resistance in the presence of higher values of cardiac index, stroke volume index and cardiac cycle efficiency.

CONCLUSION

Most Care proved to be able to detect cardiovascular abnormalities bedside in the resting state and after postural challenge in cirrhotic patients.

Haemodynamic effects of plasma-expansion with hyperoncotic albumin in cirrhotic patients with renal failure: a prospective interventional study

Background

Patients with advanced cirrhosis of the liver typically display circulatory disturbance. Haemodynamic management may be critical for avoiding and treating functional renal failure in such patients. This study investigated the effects of plasma expansion with hyperoncotic albumin solution and the role of static haemodynamic parameters in predicting volume responsiveness in patients with advanced cirrhosis.

Methods

Patients with advanced cirrhosis (Child B and C) of the liver receiving albumin substitution because of renal compromise were studied using trans-pulmonary thermodilution. Paired measurements before and after two infusions of 200 ml of 20% albumin per patient were recorded and standard haemodynamic parameters such as central venous pressure (CVP), mean arterial pressure (MAP), systemic vascular resistance index (SVRI), cardiac index (CI) and derived variables were assessed, including global end-diastolic blood volume index (GEDVI), a parameter that reflects central blood volume

Results

100 measurements in 50 patients (33 m/17 w; age 56 years (± 8); Child-Pugh-score 12 (± 2), serum creatinine 256 μmol (± 150) were analyzed. Baseline values suggested decreased central blood volumes GEDVI = 675 ml/m² (± 138) despite CVP within the normal range (11 mmHg (± 5). After infusion, GEDVI, CI and CVP increased (682 ml/m² (± 128) vs. 744 ml/m² (± 171), p < 0.001; 4.3 L/min/m² (± 1.1) vs. 4.7 L/min/m² (± 1.1), p < 0.001; 12 mmHg (± 6) vs. 14 mmHg (± 6), p < 0.001 respectively) and systemic vascular resistance decreased (1760 dyn s/cm⁵/m² (± 1144) vs. 1490 dyn s/cm⁵/m² (± 837); p < 0.001). Changes in GEDVI, but not CVP, correlated with changes in CI (r² = 0.51; p < 0.001). To assess the value of static haemodynamic parameters at baseline in predicting an increase in CI of 10%, receiver-operating-characteristic curves were constructed. The areas under the curve were 0.766 (p < 0.001) for SVRI, 0.723 (p < 0.001) for CI, 0.652 (p = 0.010) for CVP and 0.616 (p = 0.050) for GEDVI.

Conclusion

In a substantial proportion of patients with advanced cirrhosis, plasma expansion results in an increase in central blood volume. GEDVI but not CVP behaves as an indicator of cardiac preload, whereas high baseline SVRI is predictive of fluid responsiveness.

Role of echo Doppler ultrasonography in the evaluation of postprandial hyperemia in cirrhotic patients

AIM: To assess the role of echo-Doppler ultrasonography in postprandial hyperemia in cirrhotic patients by comparing the results with the hepatic vein catheterization technique.

METHODS: Patients with cirrhosis, admitted to the portal hemodynamic laboratory were included into the study. After an overnight fast, echo-Doppler ultrasonography (basal and 30 min after a standard meal) and hemodynamic studies by hepatic vein catheterization (basal, 15 min and 30 min after a standard meal) were performed. Ensure Plus (Abbot Laboratories, North Chicago, IL) was used as the standard liquid meal. Correlation analysis of the echo-Doppler and hepatic vein catheterization measurements were done for the basal and postprandial periods.

RESULTS: Eleven patients with cirrhosis (5 Child A, 4 Child B, 2 Child C) were enrolled into the study. After the standard meal, 8 of the 11 patients showed postprandial hyperemia with increase in portal blood flow, portal blood velocity and hepatic venous pressure gradient. Hepatic venous pressure gradient in the postprandial period correlated positively with postprandial portal blood velocity (r = 0.8, P < 0.05) and correlated inversely with postprandial superior mesenteric artery pulsatility index (r = -1, P < 0.01).

CONCLUSION: Postprandial hyperemia can be efficiently measured by echo-Doppler ultrasonography and the results are comparable to those obtained with the hemodynamic studies.

Cardiopulmonary complications in chronic liver disease

Patients with cirrhosis and portal hypertension exhibit characteristic cardiovascular and pulmonary hemodynamic changes. A vasodilatatory state and a hyperdynamic circulation affecting the cardiac and pulmonary functions dominate the circulation. The recently defined cirrhotic cardiomyopathy may affect systolic and diastolic functions, and imply electromechanical abnormalities. In addition, the baroreceptor function and regulation of the circulatory homoeostasis is impaired. Pulmonary dysfunction involves diffusing abnormalities with the development of the hepatopulmonary syndrome and portopulmonary hypertension in some patients. Recent research has focused on the assertion that the hemodynamic and neurohumoral dysregulation are of major importance for the development of the cardiovascular and pulmonary complications in cirrhosis. This aspect is important to take into account in the management of these patients.