Physiologic changes in the hepatopulmonary syndrome before and after liver transplant: A longitudinal and predictor analysis

BACKGROUND AND AIMS

Hepatopulmonary syndrome (HPS) is a common complication of liver disease defined by abnormal oxygenation and intrapulmonary vascular dilatation, treated with liver transplantation. Little is known about changes in HPS physiological parameters over time. We sought to describe baseline clinical and physiological characteristics in HPS and their relationships, temporal changes in physiological parameters before and after transplant, and predictors of changes in oxygenation.

APPROACH AND RESULTS

This was a retrospective cohort study in the Canadian HPS Program (n = 132). Rates of change after diagnosis were: -3.7 (-6.4, -0.96) mm Hg/year for partial pressure of arterial oxygen (PaO 2 ); -26 (-96, 44) m/year for 6-minute walk distance, and 3.3% (-6.6, -0.011) predicted/year for diffusion capacity. Noninvasive shunt of ≥ 20% predicted a slower PaO 2 decline by 0.88 (0.36, 1.4) mm Hg/month. We identified 2 PaO 2 deterioration classes-"very severe disease, slow decliners" (PaO 2 45.0 mm Hg; -1.0 mm Hg/year); and "moderate disease, steady decliners" (PaO 2 65.5 mm Hg; -2.5 mm Hg/year). PaO 2 increased by 6.5 (5.3, 7.7) mm Hg/month in the first year after transplant. The median time to normalization was 149 (116, 184) days. Posttransplant improvement in PaO 2 was 2.5 (0.1, 4.9) mm Hg/month faster for every 10 mm Hg greater pretransplant orthodeoxia.

CONCLUSIONS

We present a large and long longitudinal data analysis in HPS. In addition to rates of physiological decline and improvement before and after liver transplantation, we present novel predictors of PaO 2 decline and improvement rates. Our findings enhance our understanding of the natural history of HPS and provide pathophysiologic clues. Importantly, they may assist providers in prognostication and prioritization before and after transplant.

[Hepatopulmonary syndrome]

The hepatopulmonary syndrome (HPS) is one of the lung diseases associated with cirrhosis and portal hypertension. It should be discussed for any dyspnea in cirrhotic patients. HPS is a pulmonary vascular disease characterized by intrapulmonary vascular dilatations (IPVD). The pathogenesis is complex and seems to rely on communications between the portal and pulmonary circulations. The diagnosis is based on a triad of liver disease and portal hypertension, evidence of IPVDs, and impaired gas exchange (alveolar-arterial oxygen difference [A-aO2]≥15mmHg). HPS impairs prognosis (23% survival at 5years) and patients' quality of life. Liver transplantation (LT) allows regression of IPDVD in almost 100% of cases, normalization of gas exchange and improves survival with a 5-year post-LT survival between 76 and 87%. It is the only curative treatment, indicated in patients with severe HPS, defined by an arterial partial pressure of oxygen (PaO2) below 60mmHg. When LT is not indicated or feasible, long-term oxygen therapy may be proposed as a palliative treatment. A better understanding of the pathophysiological mechanisms is needed to improve the therapeutic possibilities in a near future.

[Effect of growth hormone supplementation on liver and lung function in patients with hypopituitarism]

To analyze the clinical features of patients with anterior hypopituitarism (HP) complicated with cirrhosis, and to explore the effects of growth hormone supplementation on liver and lung function. A total of 11 patients with HP complicated with cirrhosis admitted to Peking Union Medical College Hospital from January 2016 to December 2022 were included in the study, including 8 males and 3 females, aged [M(Q1, Q3)]31 (20, 37) years. There were 6 patients with pituitary stalk interruption syndrome, 4 patients after craniopharyngioma resection, and 1 patient after germinal cell tumor chemoradiotherapy. Cirrhosis appeared at [M(Q1, Q3)]7 (1, 16) years after the diagnosis of HP. There were 7 cases complicated with hepatopulmonary syndrome (HPS). The liver and lung function of 5 patients were improved significantly after the addition of growth hormone, and the arterial partial pressure of oxygen increased from (47±11) mmHg(1 mmHg=0.133 kPa) to (84±12) mmHg. Timely supplementation of growth hormone can improve the symptoms of fatty liver, cirrhosis and HPS, and postpone or even avoid the transplantation of liver and other organs.

[Budd-Chiari syndrome with hepatopulmonary syndrome: a case report and literature review]

Objective: To summarize the clinical features and prognosis of Budd-Chiari syndrome with hepatopulmonary syndrome (HPS) in children. Methods: The clinical data of a child who had Budd-Chiari syndrome with HPS treated at the Department of Pediatrics of the First Affiliated Hospital of Zhengzhou University in December 2016 was analyzed retrospectively. Taking "Budd-Chiari syndrome" and "hepatopulmonary syndrome" in Chinese or English as the keywords, literature was searched at CNKI, Wanfang, China Biomedical Literature Database and PubMed up to July 2023. Combined with this case, the clinical characteristics, diagnosis, treatment and prognosis of Budd-Chiari syndrome with HPS in children under the age of 18 were summarized. Results: A 13-year-old boy, presented with cyanosis and chest tightness after activities for 6 months, and yellow staining of the skin for 1 week. Physical examination at admission not only found mild yellow staining of the skin and sclera, but also found cyanosis of the lips, periocular skin, and extremities. Laboratory examination showed abnormal liver function with total bilirubin 53 μmol/L, direct bilirubin 14 μmol/L, and indirect bilirubin 39 μmol/L, and abnormal blood gas analysis with the partial pressure of oxygen of 54 mmHg (1 mmHg=0.133 kPa), the partial pressure of carbon dioxide of 31 mmHg, and the alveolar-arterial oxygen gradient of 57 mmHg. Hepatic vein-type Budd-Chiari syndrome, cirrhosis, and portal hypertension were indicated by abdominal CT venography. Contrast-enhanced transthoracic echocardiography (CE-TTE) was positive. After symptomatic and supportive treatment, this patient was discharged and received oxygen therapy outside the hospital. At follow-up until March 2023, there was no significant improvement in hypoxemia, accompanied by limited daily activities. Based on the literature, there were 3 reports in English while none in Chinese, 3 cases were reported. Among a total of 4 children, the chief complaints were dyspnea, cyanosis, or hypoxemia in 3 cases, and unknown in 1 case. There were 2 cases diagnosed with Budd-Chiari syndrome with HPS at the same time due to respiratory symptoms, and 2 cases developed HPS 1.5 years and 8.0 years after the diagnosis of Budd-Chiari syndrome respectively. CE-TTE was positive in 2 cases and pulmonary perfusion imaging was positive in 2 cases. Liver transplantation was performed in 2 cases and their respiratory function recovered well; 1 case received oxygen therapy, with no improvement in hypoxemia; 1 case was waiting for liver transplantation. Conclusions: The onset of Budd-Chiari syndrome with HPS is insidious. The most common clinical manifestations are dyspnea and cyanosis. It can reduce misdiagnosis to confirm intrapulmonary vascular dilatations with CE-TTE at an early stage. Liver transplantation is helpful in improving the prognosis.

[Pulmonary Complications in Patients with Liver Cirrhosis]

Portal hypertension is a clinical syndrome defined by an increased portal venous pressure. The most frequent cause of portal hypertension is liver cirrhosis, and many of the complications of cirrhosis, such as ascites and gastroesophageal variceal bleeding, are related to portal hypertension. Portal hypertension is a pathological condition caused by the accumulation of blood flow in the portal system. This blood flow retention reduces the effective circulation volume. To compensate for these changes, neurotransmitter hormone changes and metabolic abnormalities occur, which cause complications in organs other than the liver. A hepatic hydrothorax is fluid accumulation in the pleural space resulting from increased portal pressure. Hepatopulmonary syndrome and portopulmonary hypertension are the pulmonary complications in cirrhosis by deforming the vascular structure. Symptoms, such as dyspnea and hypoxia, affect the survival and the quality of life of patients. These lung complications are usually underestimated in the management of cirrhosis. This review briefly introduces the type of lung complications of cirrhosis.

[Improve the understanding of hepatic disease related pulmonary vascular disease]

Hepatic disease-related pulmonary vascular disease refers to the changes in the structure or function of pulmonary circulation caused by liver parenchymal or hepatic vascular diseases, mainly including hepatopulmonary syndrome characterized by hypoxemia, portopulmonary hypertension characterized by pulmonary hypertension, and hepatic vascular shunt characterized by increased cardiac output and pulmonary hypertension. Early diagnosis and treatment of liver disease and early evaluation of liver transplantation may significantly improve the prognosis for patients with hepatic disease-related pulmonary vascular disease. Moreover, it is necessary to improve clinicians' understanding of this disease and strengthen multidisciplinary cooperation, improve the level of diagnosis and treatment.

Pulmonary vascular disease and exercise hemodynamics in chronic liver disease

BACKGROUND & AIMS

Portopulmonary hypertension (POPH) and hepatopulmonary syndrome (HPS) are severe pulmonary vascular complications of chronic liver disease and strongly associated with morbidity and mortality. The prevalence of these complications is relatively high in patients evaluated for liver transplantation, however it is virtually unknown in patients with stable chronic liver disease.

METHODS

We assessed the pulmonary hypertension (PH) and HPS prevalence in a prospective registry study of our liver out-patient clinic in a tertiary center. Between 2011 and 2016, consecutive patients with cirrhosis or non-cirrhotic portal hypertension were prospectively enrolled after written informed consent. We excluded patients with acute decompensation of liver disease and other causes of PH like severe chronic heart or lung diseases and chronic thromboembolic PH. HPS was diagnosed using contrast enhanced echocardiography and blood gas analysis. Patients were screened for PH using an algorithm implementing severity of dyspnea, echocardiography, cardiopulmonary exercise testing and exercise echocardiography employing a threshold of systolic pulmonary arterial pressure (SPAP) = 50 mmHg at peak exercise. If the algorithm indicated an increased PH risk, patients were invited for invasive investigations by means of right heart and hepatic vein catheter. We defined POPH as resting mPAP≥21 mmHg and PVR>3WU and PAWP<15 mmHg, mild PH as resting mPAP = 21-24 mmHg, and exercise PH as mPAP>30 mmHg and TPR >3 WU at peak exercise.

RESULTS

Two-hundred-five patients were enrolled (male 75%; cirrhosis 96%; median age 57 yrs). Sixty-seven patients (33%) fulfilled HPS criteria but only two (1.0%) for severe (PaO2:50-60 mmHg) or very severe HPS (PaO2<50 mmHg). In 18/77 patients (23%) undergoing exercise echocardiography, SPAP at peak exercise exceeded 50 mmHg. Finally, n = 3 (1.5%) patients were invasively diagnosed with POPH, n = 4 (2.9%) with mild PH and n = 2 with exercise PH.

CONCLUSION

In chronic liver disease, excluding acute decompensation and other causes of PH, POPH and severe HPS are rare findings while mild to moderate HPS and mild PH or exercise PH are more frequent.

Hepatopulmonary syndrome as the first and only manifestation of cirrhosis in a patient with hypopituitarism

Hepatopulmonary syndrome (HPS) is characterised by the development of intrapulmonary arteriovenous blood shunts and vascular dilatation with consequent hypoxaemia, usually in the context of end-stage liver disease (ESLD). The estimated incidence of HPS in ESLD has been reported to be 13%-47%. Chronic liver disease has been described in patients with hypothalamic-pituitary dysfunction, mainly in the form of non-alcoholic fatty liver disease due to metabolic syndrome, with occasional progression to cirrhosis. We report a challenging case of a 27-year-old man with a background of hypopituitarism with no known liver disease who presented with progressive dyspnoea and hypoxaemia and was eventually diagnosed with severe HPS.

First presentation of portal hypertension complicated by hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is a serious complication of chronic liver disease, characterised by portal hypertension and arterial hypoxaemia due to intrapulmonary vascular dilatation. We report an unusual case in which a 27-year-old man had a first presentation of portal hypertension and cirrhosis complicated by HPS. This patient presented with progressive dyspnoea on exertion and deterioration in mobility, with a type 1 respiratory failure and increased oxygen demand. A bubble echocardiogram showed a possible right-to-left shunt, CT aortogram displayed evidence of portal hypertension and cirrhosis, and liver biopsy findings were consistent with alpha-1 antitrypsin deficiency. The patient's increased oxygen demand was subsequently treated with continuous positive airway pressure before he was discharged with 8 L home oxygen. With no current established medical therapy for HPS, the patient was assessed for liver transplantation and a decision was made in favour of this.

[Liver transplantation for hepatopulmonary syndrome complicating cirrhosis]

Hepato-pulmonary syndrome (HPS) is a pulmonary vascular complication of cirrhosis quite frequent but often under-diagnosed, and characterized by intra-pulmonary capillary and pre-capillary vascular dilatations that may lead to severe hypoxemia. HPS is often asymptomatic but may induce a progressive dyspnea. HPS diagnosis is based on arterial gasometry that proves the hypoxemia and contrast-enhanced echo-cardiography revealing the vascular dilatations. Screening of HPS is recommended in every cirrhotic patient complaining of dyspnea or in every liver transplantation candidate. Indeed, the only effective treatment of HPS is liver transplantation; HPS patients receive exception-points in the MELD (Model for End-Stage Liver Disease) liver allocation score. The authors report herein the case of a 39-year-old male patient with a cirrhosis of unknown origin complicated by HPS which appeared as a disabling dyspnea. This patient underwent liver transplantation a year after HPS diagnosis and recovered completely.

Non-invasive assessment of intrapulmonary shunt and ventilation to perfusion ratio in children with hepatopulmonary syndrome before and after liver transplantation

OBJECTIVES

To use the oxyhaemoglobin dissociation curve (ODC) to non-invasively measure the ventilation perfusion ratio (V_A/Q) and right-to-left intrapulmonary vascular shunt before and after liver transplantation (LT) in children with hepatopulmonary syndrome (HPS). To investigate whether the right-to-left shunt derived by ODC correlated with the shunt derived by technetium-99 labelled macroaggregated albumin lung perfusion scan (MAA).

METHODS

A retrospective cohort study at King's College Hospital NHS Foundation Trust, London, UK was performed between 1998 and 2016. The V_A/Q and right-to-left shunt were non-invasively measured pre and post LT. The pre-LT right-to-left intrapulmonary shunt was also measured by MAA. The non-invasively derived pre-LT shunt was correlated with the shunt derived by MAA.

RESULTS

Fifteen children with HPS were studied with a median (IQR) age at LT of 8.8 (6.6-12.9) years. The median (IQR) pre-LT V_A/Q [0.49 (0.42-0.65)] was lower compared to the post-LT V_A/Q [0.61 (IQR 0.54-0.72), p = 0.012]. The median (IQR) pre-LT shunt was 19 (3-24) % which decreased to zero in all but one children post-LT, (p = 0.001). The MAA-derived shunt was significantly positively correlated with the ODC-derived shunt (r = 0.783, p = 0.001). The mean (SD) difference between shunt derived by ODC and shunt derived by MAA was 0.5 (7.2) %.

CONCLUSIONS

Ventilation/perfusion impairment reverses but not completely resolves after liver transplantation in children with hepatopulmonary syndrome. The non-invasive method for estimating intrapulmonary shunting could be used as an alternative to the macroaggregated albumin scan in this population.

Hepatopulmonary Syndrome and Multiple Arteriovenous Fistulas in a Child with Niemann-Pick Disease

Background: Niemann-Pick disease (NPD) is caused by abnormal storage of sphingomyelin. NPD may affect the pulmonary system and cause hypoxia. In the present case, both hepatopulmonary syndrome (HPS) and pulmonary arteriovenous fistulas (PAVFs) developed in a child with NPD and were successfully treated with repeated embolization. Case Presentation: We have reported the case of a 16-year-old-girl with NPD who suffered severe hypoxia, dyspnea, fatigue, had multiple PAVFs, and was diagnosed with type 2 HPS. To improve oxygenation, 10 PAVFs were embolized. She needed re-embolization after 9 months because of hypoxia redevelopment. Conclusions: Pulmonary involvement, HPS, and/or PAVFs could be responsible for hypoxemia in patients with NPD, who should, therefore, be investigated for HPS and PAVFs. Embolization could be beneficial. Some patients may need repeated embolization.

Technetium-99m-labeled macroaggregated albumin lung perfusion scan for diagnosis of hepatopulmonary syndrome: A prospective study comparing brain uptake and whole-body uptake

BACKGROUND

Hepatopulmonary syndrome (HPS) is an arterial oxygenation defect induced by intrapulmonary vascular dilatation (IPVD) in the setting of liver disease and/or portal hypertension. This syndrome occurs most often in cirrhotic patients (4%–32%) and has been shown to be detrimental to functional status, quality of life, and survival. The diagnosis of HPS in the setting of liver disease and/or portal hypertension requires the demonstration of IPVD (i.e., diffuse or localized abnormally dilated pulmonary capillaries and pulmonary and pleural arteriovenous communications) and arterial oxygenation defects, preferably by contrast-enhanced echocardiography and measurement of the alveolar-arterial oxygen gradient, respectively.

AIM

To compare brain and whole-body uptake of technetium for diagnosing HPS.

METHODS

Sixty-nine patients with chronic liver disease and/or portal hypertension were prospectively included. Brain uptake and whole-body uptake were calculated using the geometric mean of technetium counts in the brain and lungs and in the entire body and lungs, respectively.

RESULTS

Thirty-two (46%) patients had IPVD as detected by contrast-enhanced echocardiography. The demographics and clinical characteristics of the patients with and without IPVD were not significantly different with the exception of the creatinine level (0.71 ± 0.18 mg/dL vs 0.83 ± 0.23 mg/dL; P = 0.041), alveolar-arterial oxygen gradient (23.2 ± 13.3 mmHg vs 16.4 ± 14.1 mmHg; P = 0.043), and arterial partial pressure of oxygen (81.0 ± 12.1 mmHg vs 90.1 ± 12.8 mmHg; P = 0.004). Whole-body uptake was significantly higher in patients with IPVD than in patients without IPVD (48.0% ± 6.1% vs 40.1% ± 8.1%; P = 0.001). The area under the curve of whole-body uptake for detecting IPVD was significantly higher than that of brain uptake (0.75 vs 0.54; P = 0.025). The optimal cut-off values of brain uptake and whole-body uptake for detecting IPVD were 5.7% and 42.5%, respectively, based on Youden’s index. The sensitivity, specificity, and accuracy of brain uptake > 5.7% and whole-body uptake > 42.5% for detecting IPVD were 23%, 89%, and 59% and 100%, 52%, and 74%, respectively.

CONCLUSION

Whole-body uptake is superior to brain uptake for diagnosing HPS.

Case Report: Hepatopulmonary syndrome as the first clinical manifestation of cirrhosis in a patient with underlying chronic lung disease

An 86 year old woman with multiple chronic lung diseases (including chronic obstructive pulmonary disease, bronchiectasis, and untreated mycobacterium avium-intracellulare) presented with two weeks of increased shortness of breath, notably worse when seated as compared to when lying down. After treatments focused on her known conditions did not resolve her dyspnea, the differential diagnosis was broadened and she was found to have evidence of cirrhosis on imaging. As a result of this new diagnosis, transthoracic echocardiography and arterial blood gas analysis were performed and together yielded the diagnosis of hepatopulmonary syndrome. We describe a rare presentation of hepatopulmonary syndrome manifesting as a patient’s first clinical evidence of suspected cirrhosis, a diagnosis made difficult by this patient’s numerous other lung diseases which muddied the picture.

Breathlessness in liver disease: A case of hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is often not considered as a cause of breathlessness in patients with liver cirrhosis. It consists of a triad of liver disease, intrapulmonary shunting and hypoxaemia. Here we discuss HPS in a patient presenting with acute on chronic breathlessness and typical features of orthodeoxia and platypnoea. Evidence of intrapulmonary shunting on imaging was essential to making the diagnosis, which carries a poor prognosis and was an urgent indication for liver transplantation.

Differential diagnosis of hepatopulmonary syndrome (HPS): Portopulmonary hypertension (PPH) and hereditary hemorrhagic telangiectasia (HHT)

Hepatopulmonary syndrome (HPS) is a severe complication of advanced liver disease associated with an extremely poor prognosis. HPS is diagnosed in 4-47% of patients with cirrhosis and in 15-20% of candidates for liver transplantation. In addition, severe hypoxia is associated with a high risk of complications of liver transplantation (a 30% chance during the first 90 days) and increases the gap between transplantation and improving arterial oxygenation. The pathogenesis of HPS is not fully understood, and no effective pharmacological treatment has been developed yet. Currently, the treatment of choice for HPS is orthotopic liver transplantation. Non-specific clinical criteria and the lack of standardized diagnostic criteria for determining HPS can lead to diagnostic errors. Portopulmonary hypertension and hereditary hemorrhagic telangiectasia, also known as Osler-Weber-Rendu syndrome, are pulmonary complications of liver disease which should be differentially diagnosed from HPS.

[Hepatopulmonary syndrome. A consideration in patients with liver disease accompanied by dyspnoea and hypoxaemia]

BACKGROUND

Hepatopulmonary syndrome is a severe complication of liver disease, with greatly increased mortality. The syndrome is characterized by increased blood-flow, intrapulmonary vasodilatation and angiogenesis, leading to effects including the formation of shunts. This leads to a decrease in arterial oxygen pressure. Liver transplantation is the only effective treatment.

CASE DESCRIPTION

A 74-year-old woman with cirrhosis of the liver attended the pulmonary outpatients' clinic with progressive dyspnoea, which worsened if she sat upright from a lying position (platypnoea). Contrast echocardiography confirmed the diagnosis 'hepatopulmonary syndrome'. The patient was not eligible for liver transplantation. She was given oxygen therapy and died from decompensated cirrhosis of the liver eighteen months later.

CONCLUSION

Early recognition of hepatopulmonary syndrome is important, because patients may be given priority for liver transplantation. Contrast echocardiography is indicated in patients with liver disease and suffering from hypoxaemia for which there is no other explanation, to reveal the presence of intrapulmonary shunt.

[Clinical and laboratory characteristics of patients with pulmonary hypertension and pulmonary vascular complications hospitalized at the Instituto Nacional de Salud del Niño]

The hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPHN) are distinct pulmonary vascular complications of portal hypertension (PHT) and are associated with increased morbidity and mortality.

OBJECTIVES

To describe the clinical and laboratory characteristics of patients with pulmonary hypertension and pulmonary vascular complications hospitalized at the Instituto Nacional de Salud del Niño.

MATERIALS AND METHODS

We included patients with HTP hospitalized from January 2012 to June 2013 and that during its evolution progressed with SHP or HTPP. For analysis, they were divided into a first group of patients with liver cirrhosis and a second group with extrahepatic portal vein obstruction.

RESULTS

Of 22 patients with HPT 45.5% were male and the age range was between 1 month and 17 years. The etiology in the group of cirrhosis (n=14) was: autoimmune hepatitis (35.7%), cryptogenic cirrhosis (35.7%), inborn error of metabolism (14.3%), chronic viral hepatitis C (7.15%) virus and atresia extra-hepatic bile ducts (7.15%). Pulmonary vascular complications more frequently occurred in patients with liver cirrhosis (1 case of HPS and a case of PPHTN). They most often dyspnea, asthenia, edema, malnutrition, ascites, hypersplenism and gastrointestinal bleeding from esophageal varices was found. Also, they had elevated ALT values, alkaline phosphatase and serum albumin values decreased.

CONCLUSIONS

In children with pulmonary hypertension, pulmonary vascular complications are rare. In the evaluation of these patients pulse oximetry should be included to detect hypoxemia and ubsequently a Doppler echocardiography and contrast echocardiography necessary. Dueto the finding of systolic pulmonary hypertension it is necessary to perform right heart catheterization.

Pulmonary complications of hepatic diseases

Severe chronic liver disease (CLD) may result from portal hypertension, hepatocellular failure or the combination of both. Some of these patients may develop pulmonary complications independent from any pulmonary pathology that they may have. Among them the hepatopulmonary syndrome (HPS), portopulmonary hypertension (PPH) and hepatic hydrothorax (HH) are described in detail in this literature review. HPS is encountered in approximately 15% to 30% of the patients and its presence is associated with increase in mortality and also requires liver transplantation in many cases. PPH has been reported among 4%-8% of the patient with CLD who have undergone liver transplantation. The HH is another entity, which has the prevalence rate of 5% to 6% and is associated in the absence of cardiopulmonary disease. These clinical syndromes occur in similar pathophysiologic environments. Most treatment modalities work as temporizing measures. The ultimate treatment of choice is liver transplant. This clinical review provides basic concepts; pathophysiology and clinical presentation that will allow the clinician to better understand these potentially life-threatening complications. This article will review up-to-date information on the pathophysiology, clinical features and the treatment of the pulmonary complications among liver disease patients.

Hepatopulmonary Syndrome: A Brief Review

Hepatopulmonary syndrome (HPS) is a pulmonary complication of liver disease characterized by arterial hypoxemia. Mechanisms related to this event are diffusion-perfusion flaw, ventilation-perfusion (V/Q) mismatch, and direct arteriovenous shunts. Diagnosis of HPS is based on the presence of liver disease or portal hypertension, increased alveolar-arterial (A-a) PO2, and intrapulmonary vascular dilatations (IPVD). Lung transplantation (LT) remains the most effective therapy for HPS. In spite of its poor prognosis, we could improve the quality of life and survival rate of patients.

[The hepatopulmonary syndrome]

The hepatopulmonary syndrome (HPS) - a complication of liver disease - seems to be underdiagnosed, probably because of decreased awareness. HPS consists of the triade liver disease, intrapulmonary vascular dilatation and as a consequence arterial hypoxaemia. No medical therapy has proven effective perhaps with the exception of garlic, which has been effective in one controlled clinical trial. However, liver transplantation seems to improve HPS in most cases. Liver patients with unexplained hypoxaemia should be investigated for HPS.

Clinical characteristics, predictors, and survival among patients with hepatopulmonary syndrome

BACKGROUND

Hepatopulmonary syndrome (HPS) is a complication of advanced liver disease. The impact of HPS on survival is not clearly understood.

MATERIAL AND METHODS

A prospective study was carried out at Department of Medicine, King Edward Medical University Lahore from June 2011 to May 2012. Patients with cirrhosis of liver were evaluated for presence of HPS with arterial blood gas analysis and saline bubble echocardiography. All patients were followed for 6 months for complications and mortality. Cox regression analysis was done to evaluate role of HPS on patient survival.

RESULTS

110 patients were included in the study. Twenty-nine patients (26%) had HPS. MELD score was significantly higher (p < 0.01) in patients with HPS (18.93 ± 3.51) as compared to that in patients without HPS (13.52 ± 3.3). Twenty two (75.9%) patients of Child class C, 5 (17.2%) patients of Child class B and 2 (6.9%) patients of Child class A had HPS (P 0.03). The clinical variables associated with presence of HPS were spider nevi, digital clubbing, dyspnea, and platypnea. HPS significantly increased mortality during six month follow up period (HR: 2.47, 95% CI: 1.10- 5.55). Child-Pugh and MELD scores were also associated with increased mortality. HPS was no longer associated with mortality when adjustment was done for age, gender, Child-Pugh, and MELD scores (HR: 0.44, 95% CI: 0.14-1.41). Both the Child-Pugh and MELD scores remained significantly associated with mortality in the multivariate survival analysis.

CONCLUSIONS

HPS indicates advanced liver disease. HPS does not affect mortality when adjusted for severity of cirrhosis.

Hepatopulmonary Syndrome, Severe Cyanosis and Marfanoid Habitus

We report the case of a 17-year-old male with Marfanoid habitus who presented with deep cyanosis, haematemesis, dyspnoea and platypnoea. He had oesophageal varices, indicating portal hypertension, with mildly deranged liver function. His arterial blood gas (ABG) revealed hypoxia and orthodeoxia. Contrast-enhanced echocardiography with agitated saline and a 99m Technetium macro-aggregated albumin perfusion lung scan confirmed intrapulmonary shunting. Pulmonary angiogram showed multiple, small diffuse pulmonary arteriovenous fistulae scattered all over the lungs and predominantly in the bases of the lungs. Based on these results and the clinical background a diagnosis of hepatopulmonary syndrome with Marfanoid habitus was made. Patient was treated conservatively as he was not prepared for liver transplantation.

Portopulmonary hypertension and hepatopulmonary syndrome

Portopulmonary hypertension (POPH) and hepatopulmonary syndrome (HPS) are two frequent complications of liver disease, with prevalence among liver transplant candidates of 6% and 10%, respectively. Both conditions result from a lack of hepatic clearance of vasoactive substances produced in the splanchnic territory. Subsequently, these substances cause mainly pulmonary vascular remodeling and some degree of vasoconstriction in POPH with resulting elevated pulmonary pressure and right ventricular dysfunction. In HPS the vasoactive mediators cause intrapulmonary shunts with hypoxemia. Medical treatment is disappointing overall. Whereas liver transplantation (LT) results in the disappearance of HPS within six to twelve months, its effect on POPH is highly unpredictable. Modern strategies in managing HPS and POPH rely on a thorough screening and grading of the disease’s severity, in order to tailor the appropriate therapy and select only the patients who will benefit from LT. The anesthesiologist plays a central role in managing these high-risk patients. Indeed, the important hemodynamic and respiratory modifications of the perioperative period must be avoided through continuation of the preoperatively initiated drugs, appropriate intraoperative monitoring and proper hemodynamic and respiratory therapies.

[Hepatopulmonary syndrome causing severe hypoxaemia]

Dyspnoea is a common complaint in patients with chronic liver disease. Hepatopulmonary syndrome (HPS) is an important cause to be aware of in the setting of liver disease, dyspnoea and hypoxaemia. HPS causes microvascular dilatation, angiogenesis and arteriovenous bypassing. The patients suffer from hypoxaemia in upright position and even during minimal psychical activity. Contrast echocardiography, using micro-bubbles as the contrast, is required to establish the diagnosis. No medical therapy is available, only liver transplantation can cure the disease.

Cirrhosis and hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is characterized as a triad: liver disease, intrapulmonary vascular dilatation and arterial hypoxemia. HPS is reported to be present in 4% to 32% of adult patients with end-stage liver disease and in 9%-20% of children. The pathogenesis of HPS has not been clearly identified. Portal hypertension causes impairment in the perfusion of the bowel and increases the enteral translocation of Gram (-) bacteria and endotoxins. This stimulates the release of vasoactive mediators, such as tumor necrosis factor-alpha, heme oxygenase-derived carbon monoxide and nitric oxide. Genetic alterations have not been associated with this syndrome yet; however, cytokines and chemokines have been suggested to play a role. Recently, it was reported that cumulated monocytes lead to the activation of vascular endothelial growth factor-dependent signaling pathways and pulmonary angiogenesis, which plays an important role in HPS pathogenesis. At present, the most effective and only radical treatment is a liver transplant (LT). Cirrhotic patients who are on the waiting list for an LT have a shorter survival period if they develop HPS. Therefore, it is suggested that all cirrhotic cases should be followed closely for HPS and they should have priority in the waiting list.

Pulse oximetry is insufficient for timely diagnosis of hepatopulmonary syndrome in children with liver cirrhosis

OBJECTIVE

To prospectively investigate the prevalence of hepatopulmonary syndrome (HPS), the importance of pulse oximetry in diagnosing HPS, and the longitudinal course after liver transplantation in children with cirrhosis referred for liver transplantation.

STUDY DESIGN

Fifty-six patients aged 1-17 years (mean age, 4.6 ± 5.0 years) with liver cirrhosis were screened for HPS by hyperemic capillary blood gas (CBG) analysis and contrast-enhanced transthoracic echocardiography. Eleven patients were excluded owing to conditions that can produce cardiopulmonary dysfunction, including 5 with cystic fibrosis, 1 with pulmonary arterial hypertension, and 5 with an intracardial shunt. HPS was classified in accordance with the European Respiratory Society Task Force criteria on pulmonary-hepatic disorders. Patient groups were compared for biochemical and clinical characteristics.

RESULTS

Eighteen children (40%) with cirrhosis were intrapulmonary vasodilatation (IPVD)-positive and had a pulse oximetry oxygen saturation level >98%. Two of these patients (11%) exhibited moderate HPS with an elevated alveolar arterial oxygen gradient >15 mm Hg and PaO2 <70 mm Hg; they died before undergoing liver transplantation. The sensitivity and specificity of CBG analysis for detecting elevated alveolar arterial oxygen gradient in children with IPVD was 94% and 53%, respectively. HPS was associated with late hepatoportoenterostomy (P < .04). Liver transplantation led to resolution of HPS in all patients.

CONCLUSION

IPVD is frequent in children with liver cirrhosis (40%). Pulse oximetry is insufficient for timely HPS diagnosis. Pathological CBG analysis data indicate IPVD in the majority of cases, but are imprecise in children aged <2 years. Contrast-enhanced transthoracic echocardiography and CBG analysis are recommended for evaluation of HPS in children with cirrhosis, regardless of liver synthesis capacity and clinical chemistry data.

[Hepatopulmonary syndrome]

Hepatopulmonary syndrome (HPS) is characterized by the triad of liver disease, intrapulmonary vascular dilatation and arterial deoxygenation. Mediating factors are tumor necrosis factor a, endothelin 1 and nitric oxide. Typical symptom is an increase in dyspnea while in standing position, orthodeoxia. In orthodeoxia hypoxemia accentuates while the partial pressure of oxygen in arterial blood decreases by 5% or more. The blood flow distribution to the lungs is changed as the pulmonary vascular tone is altered. Diagnosis is based on the evidence of liver disease, hypoxemia and pulmonary vascular shunt detected by the so-called bubble test. Liver transplantation is currently the only efficient therapeutic option.

Paradoxical arterial hypoxemia in a left-to-right shunt congenital heart disease

The hepatopulmonary syndrome is a rare complication of different types of chronic hepatic diseases with associated portal venous hypertension, resulting in pulmonary vascular dilatation, predominantly in the lower lung fields, and leading to ventilation-perfusion mismatch, arterial hypoxemia and a poor prognosis. We present the case of 42-year-old male patient with an anomalous drainage of the right superior pulmonary vein into the azygos vein and a portal vein cavernomatosis with associated portal venous hypertension who presented severe oxygen desaturation, during exercise, in the context of a hepatopulmonary syndrome.

Respiratory system involvement in chronic liver diseases

Liver diseases are often associated with respiratory complications. They may manifest as pleural effusion, interstitial lung disease, as well as various combinations of symptoms affecting the pulmonary vasculature. The duration and severity of liver disease is not always reflected by the degree of lung function impairment. On the other hand, progressive damage to the lungs significantly worsens prognosis in the course of severe liver disease. The diagnosis is difficult and often requires multidisciplinary cooperation. The effects of pharmacological treatment are not always satisfactory. In numerous cases, liver transplantation proves to be the best option.

Screening of hepatopulmonary syndrome (HPS) with CEUS and pulse-oximetry in liver cirrhosis patients eligible for liver transplant

BACKGROUND AND AIM

The prevalence of hepatopulmonary syndrome (HPS) in the setting of cirrhosis ranges between 4%-47%. We aimed to detect a correlation between heart and lungs findings on contrast-enhanced ultrasound (CEUS)and pulse-oximetry, in order to early detect HPS and thus to improve patients referral to orthotopic liver transplantation(OLT).

METHODS

We considered at risk for HPS all patients with delayed left ventricle (LV) enhancement of the contrast agent,at least 3 systolic beats after it appears in the right ventricle(RV). We correlated CEUS results with pulse-oximetry findings,considering to have a positive HPS diagnosis in all patients with both CEUS findings and SaO2 95%.

RESULTS

From 186 patients diagnosed with liver cirrhosis, 56 patients (30.10%) had delayed LV enhancement of the contrast agent. Pulse-oximetry showed alterations, such as SaO2 95%and PaO2 70 mmHg in 62 patients (33.33%). Pearson index showed a good correlation between lung and heart CEUS findings and pulse-oximetry (r=0.99) in HPS diagnosis. CONCLUSIONS. Two non-invasive, simple and rapid methods such as CEUS and pulse-oximetry can easily diagnose HPS, a highly fatal complication of liver cirrhosis, and can also guide the future treatment by speeding up OLT recommendations.

[Hepatopulmonary syndrome: a complication of type 1 Gaucher disease]

Gaucher's disease is a not exceptional lysosomial disease in Tunisia. Type 1 is by far the most common one. Pulmonary involvement is considered to be rare in type 1 Gaucher's disease. Pulmonary hypertension, infiltration of the lungs with Gaucher cells, and severe hypoxemia due to intrapulmonary arterial-venous shunts, have been described in case reports and small case series. We reported the case of hepatopulmonary syndrome in a 14-year-old boy with type 1 Gaucher disease. The diagnosis of Gaucher disease was established, at 2 years age, by enzyme assay of leucocyte β-glucosidase. The patient presented dyspnoea, digital clubbing and cyanosis of the lips. The arterial blood gas found severe hypoxaemia with PaO(2) at 56.9 mmHg. The diagnosis of hepatopulmonary syndrome, in our patient, was confirmed by demonstration of the intrapulmonary shunting using contrast-enhanced echocardiography and the technetium-99m-labeled macroaggregated albumin. The patient was treated by symptomatic measure, long term oxygen therapy because the insufficiency of the enzyme replacement therapy. Screening for hypoxemia in children with liver disease should be considered.

Pulmonary complications of cirrhosis

Pulmonary vascular complications of liver disease comprise two distinct clinical entities: hepatopulmonary syndrome (HPS-microvascular dilatation and angiogenesis) and portopulmonary hypertension (POPH-vasoconstriction and remodeling in resistance vessels). These complications occur in similar pathophysiologic environments and may share pathogenic mechanisms. HPS is found in 15% to 30% of patients with cirrhosis and its presence increases mortality and the risks of liver transplantation, particularly when hypoxemia is present. Contrast echocardiography and arterial blood gas analysis are required to establish the diagnosis. No medical therapies are available, although liver transplantation is effective in reversing the syndrome. POPH is found in 4% to 8% of patients undergoing liver transplantation evaluation, and the presence of moderate to severe disease significantly increases perioperative transplant mortality. Transthoracic echocardiography is recommended for screening and right-heart catheterization is required to establish the diagnosis. Medical therapies are increasingly effective in improving pulmonary vascular hemodynamics in POPH and may result in better perioperative outcomes.

Hepatopulmonary syndrome: prevalence and predictors in Egyptian cirrhotic patients

BACKGROUND

The reported prevalence of hepatopulmonary syndrome (HPS) in cirrhotic patients is heterogeneous. Although the prevalence of chronic liver diseases is high in Egypt, however, scanty data is available about HPS.

AIM

To assess the frequency of HPS and factors predictive of diagnosis of HPS in Egyptian patients with liver cirrhosis.

METHODS

Fifty cirrhotic patients were evaluated for the presence of HPS. Orthodeoxia was measured by arterial blood gas test. The patients positive for diagnostic criteria of HPS (the presence of A-a O2 > or = 15 mmHg and pulmonary vascular dilatation assessed by contrast enhanced echocardiography) were defined as clinical HPS cases and those manifesting with intrapulmonary arterial dilation but no other criteria were defined as subclinical HPS cases.

RESULTS

Subclinical HPS and clinical HPS was observed in 10 (20%) and 17 (34%) of the patients, respectively. The presence of HPS was significantly associated with severity of liver disease assessed by the Child-Pugh score (CP) or MELD score. Portal vein diameter (mm) (OR 3.3; 95% C.I 1.3-8.2; p=0.01) was the only independent predictor for HPS; the specificity of orthodeoxia for diagnosis of HPS was 100%.

CONCLUSIONS

HPS and intrapulmonary vein dilation are relatively frequent in patients with liver cirrhosis and occur in 34% and 20% of cirrhosis patients, respectively. They are associated with disease severity according to the MELD and CP score. Alveolar arterial oxygen gradient is the most valuable negative and positive diagnostic predictor for presence of HPS in cirrhotic patients.

[Pulmonary affection in advanced liver disease - hepatepulonary syndrome and portopulmonary hypertension]

Patients suffering from severe chronic liver disease, in particular cirrhosis, are at risk for pulmonary complications. The leading clinical symptom is shortness of breath, which can accompany the actual disease as indirect effect because of anemia, faint muscles or ascites. On the other hand, dyspnea can have multiple additive causes in case of accompanying cardial or pulmonary disease. The hepatopulmonary syndrome (HPS) and the portopulmonary hypertension (PoPH) belong to the most relevant pulmonary complications in liver cirrhosis. HPS appears to be more common than PoPH and the presence of either entity increases morbidity and mortality in patients with liver disease. The two diseases have to be strictly distinguished, as they have opposed histological and pathophysiological origin. While the HPS is a dilatative pulmonary- vascular disease, the PoPH is a constrictive or obliterative pulmonary-vascular disease in the context of a liver disease or a portal hypertension. Therefore, these diseases are separate entities also when it comes to diagnostics and therapy.

[Hepato-pulmonary syndrome]

The hepato-pulmonary syndrome (HPS) is a rare complication of liver cirrhosis, with poor outcome; the term includes liver disease, increased alveolo-arterial gradient and intrapulmonary vascular dilations, described by Fluckiger, Kennedy and Knudson. HPS impairs survival in cirrhotic patients and the posttransplant outcome is altered in correlation with severity of HPS. Combined determination of SaO2 in clino- and orthostatic position by a pulsoximeter is a simple test for HPS identification in patients with chronic liver disease or non-cirrhotic portal hypertension.

[Hepatopulmonary syndrome: case report and literature review]

Hepatopulmonary syndrome is an important complication of chronic liver disease occurring in 16 24% of patients. It is characterized by an increase in alveolar -capillary gradient, with or without hypoxemia, due to intrapulmonary vasodilatation. The course of the disease is progressive and associated with increased morbidity and mortality. There is no effective medical treatment and liver transplant is a priority. To exemplify the authors present the case of a 39 year -old male patient sent to the Pulmonology outpatient clinic and presenting with secondary polycythemia and progressive exertional dyspnoea. Clinical investigation identified a hepatopulmonary syndrome.

Physiopathological, clinical and therapeutic aspects of hepatopulmonary syndrome

Patients with cirrhosis or portal hypertension may develop hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPHT). HPS occurs in 25% of the subjects with chronic hepatopathy waiting for a liver transplantation. HPS is characterized by chronic hepatopathy and/or portal hypertension, increased P(A-a)O2 gradient (more than 20 mmHg) with hypoxemia and intrapulmonary vascular dilatations without a primary cardiovascular disease. Hypoxiemia is due to intrapulmonary arteriovenous shunts and to dilatation of microvessels in basal parts of the lung and of pleural vessels. In patients with cirrhosis an impaired cardiovascular function is frequent, often in a subclinical phase of the disease. Left ventricular systolic and diastolic dysfunction may develop a chronic hepatopathy and the relation between right ventricular and liver failure has been studied. During cirrhosis characteristic alterations of systemic hemodynamic can cause the hyperdynamic circulatory syndrome. Contrast enhanced 2D ECHO cardiography is the preferred screening test for intrapulmonary arteriovenous shunts. The aim of HPS therapy is to contrast intrapulmonary vasodilatation, increased portal flux and hyperdynamic syndrome. New therapeutical agents are fosfodiesterase inhibitors, ET-1 receptor antagonists and selective NOS inhibitors. However, medical treatment is not much effective in HPS and liver transplantation is considered the only therapeutical chance.

Pulmonary vascular complications in asymptomatic children with portal hypertension

OBJECTIVES

: To determine the prevalence of portopulmonary hypertension, hepatopulmonary syndrome (HPS), and intrapulmonary vascular shunting (IPVS) in children with clinically stable portal hypertension and to assess the value of vasoactive peptide levels, biochemical tests and clinical signs or symptoms to predict these conditions.

PATIENTS AND METHODS

: A prospective, cross-sectional analysis was conducted on 33 children, ages 4 to 17 years, with stable cirrhosis (n = 28) or extrahepatic portal hypertension (n = 5). The children were screened for IPVS and hypoxia with contrast-enhanced echocardiography (cECHO) and pulse oximetry, and screened for pulmonary hypertension with Doppler echocardiography. Chemistries, radiographs, physical examinations, and levels of vasoactive peptides were compared between subjects with IPVS and those with normal cECHO.

RESULTS

: No subject had pulmonary hypertension. Six (19%) had IPVS, all of which had intrahepatic causes of portal hypertension, and 1 of whom had HPS. Compared with subjects with normal cECHO, those with IPVS had biochemical evidence of more advanced liver disease and higher b-type natriuretic peptide levels.

CONCLUSIONS

: Prevalence of portopulmonary hypertension and HPS appear to be rare in clinically stable children with portal hypertension. Intrapulmonary vascular shunting was present in 19% of these patients. A novel finding of this study is the elevation of b-type natriuretic peptide in children with IPVS.

Pulmonary complications of cirrhosis

Advanced liver disease and portal hypertension produce various intrathoracic complications that involve the pleural space, the lung parenchyma, and the pulmonary circulation. Dyspnea and arterial hypoxemia are the most common symptoms and signs in patients with such complications. This article focuses on the diagnosis and management of hepatopulmonary syndrome, portopulmonary hypertension, and hepatic hydrothorax. All are pulmonary processes associated with end-stage liver disease that lead to significant morbidity and affect the quality of life of patients who are suffering from liver cirrhosis.

Hepatopulmonary syndrome: an update

Hepatopulmonary syndrome (HPS) is a clinical threesome composed of liver disease, intrapulmonary vascular dilatation (IPVD) and arterial gas abnormalities. Its occurrence has been described in up to 32% of cirrhotic candidates for liver transplantation. It also affects non-cirrhotic patients with portal hypertension. Its pathogenesis is not well defined, but an association of factors such as imbalance in the endothelin receptor response, pulmonary microvascular remodeling and genetic predisposition is thought to lead to IPVD. Diagnosis is based on imaging methods that identify these dilatations, such as contrast echocardiography or perfusion scintigraphy with 99mTc, as well as analysis of arterial gases to identify elevated alveolar-arterial differences in O2 or hypoxemia. There is no effective pharmacological treatment and complete resolution only occurs through liver transplantation. The importance of diagnosing HPS lies in prioritizing transplant candidates, since presence of HPS is associated with worse prognosis. The aim of this paper was to review the pathogenetic theories and current diagnostic criteria regarding HPS, and to critically analyze the prioritization of patients with HPS on the liver transplant waiting list. Searches were carried out in the Medline (Medical Literature Analysis and Retrieval System Online) via PubMed, Cochrane Library and Lilacs (Literatura Latino-Americana e do Caribe em Ciências da Saúde) databases for articles published between January 2002 and December 2007 involving adults and written either in English or in Portuguese, using the term hepatopulmonary syndrome. The studies of greatest relevance were included in the review, along with text books and articles cited in references that were obtained through the review.