Clinical and haemodynamic aspects of hepatopulmonary syndrome in Indian patients with cirrhosis

Etiological Spectrum of Cirrhosis in India: A Systematic Review and Meta-analysis

BACKGROUND

Cirrhosis is a significant cause of morbidity and mortality globally and in India. This systematic review and meta-analysis aimed to ascertain the etiological spectrum and changing trends of cirrhosis in India.

METHODS

We searched electronic databases, including Pubmed/Medline, Scopus, and Embase. We included original studies that reported the etiology of cirrhosis in the Indian population.

RESULTS

We included 158 studies (adults: 147, children: 11). The overall pooled estimate of alcohol as a cause of cirrhosis in adults was 43.2% (95% confidence interval (CI) 39.8-46.6%; I2 = 97.8%), followed by nonalcoholic fatty liver disease (NAFLD)/cryptogenic in 14.4%, 95% CI (11.7-17.3%; I2 = 98.4%), hepatitis B virus (HBV) in 11.5%, 95% CI (9.8-13.3%; I2 = 96.6%), and hepatitis C virus (HCV) in 6.2%, 95% CI (4.8-7.8%; I2 = 97.2%) of the included patients. The most common cause of cirrhosis in all zones was alcohol-related. Comparison of etiologies over time revealed a reduction in the viral hepatitis-related and an increase in the proportion of alcohol-related and NAFLD/cryptogenic-related cirrhosis. The overall pooled estimates of various etiologies in children were: HBV in 10.7%, 95% CI (4.6-18.7%; I2 = 91.0%), NAFLD/Cryptogenic in 22.3%, 95% CI (9.0-39.2%; I2 = 96.7%), and HCV in 2.0%, 95% CI (0.0-8.5%; I2 = 94.6%).

CONCLUSIONS

Alcohol is the most common etiology of cirrhosis in adults in India. The proportions of alcohol and NAFLD-related cirrhosis are increasing, and those of viral hepatitis-related cirrhosis are reducing. The results of our meta-analysis will help formulate health policies and the allocation of resources.

Acid-base abnormalities and liver dysfunction

In addition to the kidneys and lungs, the liver also plays an important role in the regulation of the Acid-Base Equilibrium (ABE). The involvement of the liver in the regulation of ABE is crucial because of its role in lactic acid metabolism, urea production and in protein homeostasis. The main acid-base imbalance that occurs in patients with liver cirrhosis is Respiratory Alkalosis (RAlk). Due to the fact that in these patients additional pathophysiological mechanisms that affect the ABE are present, other disorders may appear which compensate or enhance the primary disorder. Conventional ABE reading models fail to identify and assess the underlying disorders in patients with liver cirrhosis. This weakness of the classical models led to the creation of new physicochemical mathematical models that take into account all the known parameters that develop and affect the ABE. In addition to the RAlk, in patients with liver cirrhosis, metabolic alkalosis (due to hypoalbuminemia), hyponatremic metabolic acidosis, hyperchloremic metabolic acidosis, lactic acidosis and metabolic alkalosis due to urea metabolism are some of the pathophysiological mechanisms that affect the ABE.

Hepatopulmonary Syndrome in children: a comparative study of non-cirrhotic vs. cirrhotic portal hypertension

BACKGROUND & AIMS

Hepatopulmonary syndrome in children has not been extensively studied particularly in different subsets of portal hypertension. We prospectively studied hepatopulmonary syndrome in children with cirrhosis and extrahepatic portal venous obstruction. Their comparison might shed light on the pathogenesis of hepatopulmonary syndrome.

METHODS

Between 1 to 18 years of age, 135 children with portal hypertension (cirrhosis 35, extrahepatic portal venous obstruction 100) were studied. Hepatopulmonary syndrome was diagnosed by the presence intrapulmonary shunt using transthoracic contrast echocardiography and hypoxia/orthodeoxia (in arterial blood gas examination). Comparative analyses were done for both the groups, and also intra- and intergroups with and without hepatopulmonary syndrome.

RESULT

Of 135 children, hepatopulmonary syndrome occurred more frequently in cirrhosis (40%) than extrahepatic portal venous obstruction (13%) (P = 0.01). Cirrhotics with hepatopulmonary syndrome were symptomatic (85% vs. 14%, P < 0.001) and had longer disease duration [16(1-120) months vs. 28 (1-168) months, P = 0.01] as compared to cirrhotics without hepatopulmonary syndrome. Prevalence of hepatopulmonary syndrome among cirrhotics did not correlate with the severity of liver disease as assessed by both paediatric end-stage liver disease score and Child-Turcotte-Pugh score. Patients with extrahepatic portal venous obstruction and hepatopulmonary syndrome remain asymptomatic manifesting with clubbing alone (38%).

CONCLUSIONS

Hepatopulmonary syndrome occurs more frequently in cirrhosis, a majority being symptomatic with more severity in comparison to extrahepatic portal venous obstruction having no symptoms and less severity. There seems to be a role of liver dysfunction besides portal hypertension as an added factor in the pathogenesis of hepatopulmonary syndrome.

Clinical applications of lung function tests: a revisit

The development and clinical application of lung function tests have a long history, and the various components of lung function tests provide very important tools for the clinical evaluation of respiratory health and disease. Spirometry, measurement of the diffusion factor, bronchial provocation tests and forced oscillation techniques have found diverse clinical applications in the diagnosis and monitoring of respiratory diseases, such as chronic obstructive pulmonary disease, interstitial lung diseases and asthma. However, there are some practical issues to be resolved, including the establishment of reference values for individual test parameters and the roles of these tests in preoperative risk assessment and pulmonary rehabilitation. Novel measurements, including negative expiratory pressure, the fraction of exhaled nitric oxide and analysis of exhaled breath condensate, may provide new insights into physiological abnormalities or airway inflammation in respiratory diseases, but their clinical applications need to be further evaluated. The clinical application of lung function tests continues to face challenges, which may be overcome by further improvement of conventional techniques for lung function testing and further specification of new testing techniques.

Detection of hepatopulmonary syndrome in patients with liver cirrhosis using 3D contrast echocardiography

BACKGROUND AND STUDY AIMS

Hepatopulmonary syndrome (HPS) is characterised by the triad of advanced liver disease, arterial hypoxaemia and intrapulmonary vascular dilatation (IPVD). The present study aimed to evaluate HPS in patients with liver cirrhosis and the role of three-dimensional (3D) contrast echocardiography in the detection of this syndrome.

PATIENTS AND METHODS

A total of 78 chronic liver disease patients aged 42 ± 11 years fulfilled the criteria for this study and were subjected to clinical examination, laboratory investigations, arterial blood gases measurement, pulmonary function tests, upper gastrointestinal endoscopy, 3D contrast echocardiography and computed tomography (CT) pulmonary angiography.

RESULTS

According to 3D contrast echocardiography results, we divided the patients into a positive group (n=26) in which patients showed a delayed appearance of contrast in left heart chambers and a negative group (n=52). Among 26 patients of the positive group, nine had hypoxaemia (partial pressure of oxygen (PaO(2)) <70 mm Hg) and were diagnosed as having hepatopulmonary syndrome (HPS), the other 17 who had shown echocardiographic evidence of IPVDs but without hypoxaemia were diagnosed as having sub-clinical HPS. This study showed significant correlation between positive contrast echocardiography findings and duration of liver disease, Child score, cyanosis, clubbing, orthodeoxia, portal vein diameter, spleen size and oesophageal varices grades. No significant correlation was found between 3D contrast echocardiography findings and age, sex, spider naevi and pulmonary function tests. Multivariate logistic regression showed that cyanosis, clubbing, orthodeoxia, Child score and portal vein diameter are independent predictors of HPS.

CONCLUSION

Cyanosis, clubbing and platypnoea-orthodeoxia are suggestive indicators of HPS, which can be easily detected by 3D contrast echocardiography which can replace the trans-oesophageal echocardiogram (TEE) in cirrhotic patients.

Alterations in arterial blood parameters in patients with liver cirrhosis and ascites

In cirrhotic patients, in addition to hepatocytes and Kuppfer cells dysfunction circulatory anatomic shunt and ventilation/perfusion (V(A)/ Q) ratio abnormalities can induce decrease in partial pressure of oxygen in arterial blood (PaO(2)), in oxygen saturation of hemoglobin (SaO(2)) as well as various acid-base disturbances. We studied 49 cases of liver cirrhosis (LC) with ascites compared to 50 normal controls. Causes were: posthepatic 37 (75.51%), alcoholic 7 (14.24%), cardiac 2 (4.08%), and cryptogenic 3 (6.12%). Complications were: upper gastrointestinal bleeding 24 (48.97), hepatic encephalopathy 20 (40.81%), gastritis 28 (57.14%), hepatoma 5 (10.2%), renal hepatic syndrome 2 (4.01%), HbsAg (+) 24 (48.97%), and hepatic pleural effusions 7 (14.28%). Average PaO(2) and SaO(2) were 75.2 mmHg and 94.5 mmHg, respectively, compared to 94.2 mmHg and 97.1 mmHg of the control group, respectively (p value in both PaO(2) and SaO(2 )was p<0.01). Respiratory alkalosis, metabolic alkalosis, metabolic acidosis, respiratory acidosis and metabolic acidosis with respiratory alkalosis were acid-base disturbances observed. In conclusion, portopulmonary shunt, intrapulmonary arteriovenous shunt and V(A)/Q inequality can induce a decrease in PaO(2) and SaO(2) as well as various acid-base disturbances. As a result, pulmonary resistance is impaired and patients more likely succumb to infections and adult respiratory distress syndrome.

Occurrence of hepatopulmonary syndrome in Budd-Chiari syndrome and the role of venous decompression

BACKGROUND & AIMS

Hepatopulmonary syndrome (HPS) has been predominantly detected in cirrhotic patients and rarely in patients with noncirrhotic portal hypertension. The aim of this study was to determine the occurrence of HPS in patients with Budd-Chiari syndrome (only anecdotal reports available) and evaluate the role of venous decompression in its reversal.

METHODS

Twenty-nine consecutive cases of Budd-Chiari syndrome without primary cardiopulmonary disease were investigated by air contrast echocardiography and arterial blood gas analysis. Venous decompression (e.g., by balloon cavoplasty) was attempted when feasible.

RESULTS

Eight cases (27.6%) of HPS and 9 cases (31.0%) with positive contrast echocardiography but unimpaired oxygenation were detected. Duration of disease was longer (P = 0.026) among those with positive contrast echocardiography. Cavoplasty reversed 4 of 5 cases of HPS and 2 of 2 cases with positive contrast echocardiography alone. Venous decompression by drainage of amebic liver abscess (which was compressing hepatic venous outflow) also reversed 1 case of HPS. HPS was relieved by venous decompression in 5 of 6 cases.

CONCLUSIONS

HPS developed in a substantial fraction of our patients with Budd-Chiari syndrome, with positive contrast echocardiography occurring mainly in the benign, slowly progressing variety. Venous decompression showed promise in reversing such cases.

Prevalence of hepatopulmonary syndrome in cirrhosis and extrahepatic portal venous obstruction

OBJECTIVE

Hepatopulmonary syndrome (HPS) is characterized by arterial hypoxemia in patients with chronic liver disease caused by abnormal intrapulmonary vasodilations. Data on its frequency vary from 5% to 29%. Most of these studies are from the West and in patients with cirrhosis. We, therefore, studied the prevalence of HPS in patients with liver cirrhosis and extrahepatic portal venous obstruction (EHPVO).

METHODS

We studied 54 consecutive patients with liver cirrhosis (42 men and 12 women; mean age = 44.2 +/- 13 yr; Child grade A: 13, B: 22, and C: 19) and 50 patients with EHPVO (31 men and 19 women; mean age = 23.3 +/- 7.8 yr) Diagnosis of cirrhosis was made by history, liver function abnormalities, endoscopy, and sonography, whereas EHPVO was diagnosed by demonstration of a block in the splenoportovenous axis on sonography. Each of the patients underwent chest x-ray, arterial blood gas analysis, contrast-enhanced echocardiography (CEE), and pulmonary function tests. HPS was diagnosed in a patient with positive CEE, in the presence of hypoxia (PaO2 < 70 mm Hg) and/or elevated alveolar arterial oxygen gradient of > 20 mm Hg in the absence of any underlying cardiopulmonary disease.

RESULTS

Ten of 54 patients (18.5%) with cirrhosis were positive on CEE compared with two of 50 patients (4%) with EHPVO. Six of the 10 patients positive with cirrhosis for CEE had associated hypoxia, whereas only one EHPVO patient with positive CEE had an elevated pulmonary alveolar arterial oxygen gradient of > 20 mm Hg. Thus, the incidence of HPS was 11.1% in patients with cirrhosis, compared with 2% in patients with EHPVO. One patient with HPS and cirrhosis had clinical cyanosis.

CONCLUSION

HPS occurs more commonly in patients with cirrhosis but can also be seen in patients with EHPVO.

Hepatopulmonary syndrome in poorly compensated postnecrotic liver cirrhosis by hepatitis B virus in Korea

BACKGROUND

Hepatopulmonary syndrome (HPS) refers to the association of hypoxemia, intrapulmonary shunting and chronic liver disease. But there is no clear data about the prevalence of HPS in postnecrotic liver cirrhosis by hepatitis B virus (HBV), the most common cause of liver disease in Korea. The aim of this study was to investigate the prevalence of HPS in poorly compensated postnecrotic liver cirrhosis by HBV, and the correlation of the hepatopulmonary syndrome with clinical aspects of postnecrotic liver cirrhosis by HBV.

METHODS

Thirty-five patients underwent pulmonary function test, arterial blood gas analysis and contrast-enhanced echocardiography. All patients were diagnosed as HBV-induced Child class C liver cirrhosis and had no evidence of intrinsic cardiopulmonary disease.

RESULTS

Intrapulmonary shunt was detected in 6/35 (17.1%) by contrast-enhanced echocardiography. Two of six patients with intrahepatic shunts had significant hypoxemia (PaO2 < 70 mmHg) and four showed increased alveolar-arterial oxygen gradient over 20 mmHg. Only cyanosis could reliably distinguish between shunt positive and negative patients.

CONCLUSIONS

The prevalence of intrapulmonary shunt in poorly compensated postnecrotic liver cirrhosis by HBV was 17.1% and the frequency of hepatopulmonary syndrome was relatively low (5.7%). 'Subclinical' hepatopulmonary syndrome (echocardiographically positive intrapulmonary shunt but without profound hypoxemia) exists in 11.4% of cases with poorly compensated postnecrotic liver cirrhosis by HBV. Cyanosis is the only reliable clinical indicator of HPS of HBV-induced poorly compensated liver cirrhosis. Further studies are required to determine if the prevalence and clinical manifestations of HPS varies with etiology or with geographical and racial differences.