Hepatogenic pulmonary angiodysplasia treated with coil-spring embolization

Proposed management algorithm for severe hypoxemia after liver transplantation in the hepatopulmonary syndrome

The hepatopulmonary syndrome (HPS) is defined as the triad of liver disease, intrapulmonary vascular dilatation, and abnormal gas exchange, and is found in 10-32% of patients with liver disease. Liver transplantation is the only known cure for HPS, but patients can develop severe posttransplant hypoxemia, defined as a need for 100% inspired oxygen to maintain a saturation of ≥85%. This complication is seen in 6-21% of patients and carries a 45% mortality. Its management requires the application of specific strategies targeting the underlying physiologic abnormalities in HPS, but awareness of these strategies and knowledge on their optimal use is limited. We reviewed existing literature to identify strategies that can be used for this complication, and developed a clinical management algorithm based on best evidence and expert opinion. Evidence was limited to case reports and case series, and we determined which treatments to include in the algorithm and their recommended sequence based on their relative likelihood of success, invasiveness, and risk. Recommended therapies include: Trendelenburg positioning, inhaled epoprostenol or nitric oxide, methylene blue, embolization of abnormal pulmonary vessels, and extracorporeal life support. Availability and use of this pragmatic algorithm may improve management of this complication, and will benefit from prospective validation.

[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.

Effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome

AIM: To study the effect of oral garlic on arterial oxygen pressure in children with hepatopulmonary syndrome.

METHODS: Garlic powder in a capsule form was given to 15 children with hepatopulmonary syndrome (confirmed by contrast echocardiography) at the dosage of 1 g/1.73 m² per day. Patients were evaluated clinically and by arterial blood gas every four weeks.

RESULTS: The garlic capsule was administered to 15 patients with hepatopulmonary syndrome. There were 10 boys and 5 girls with a mean age of 9.4 ± 3.9 years. The underlying problems were biliary tract atresia (4 patients), autoimmune hepatitis (4 patients), cryptogenic cirrhosis (4 patients) and presinusoidal portal hypertension (3 patients). Eight patients (53.3%) showed an increase of 10 mmHg in their mean arterial oxygen pressure. The baseline PaO₂ was 65.6 ± 12.1 mmHg in the responder group and 47.1 ± 11.2 mmHg in non-responder group. At the end of treatment the mean PaO₂ in responders and non-responders was 92.2 ± 7.75 mmHg and 47.5 ± 11.87 mmHg, respectively (P < 0.01).

CONCLUSION: Garlic may increase oxygenation and improve dyspnea in children with hepatopulmonary syndrome.

Síndrome hepatopulmonar: patogenia, diagnóstico e tratamento

RACIONAL: A síndrome hepatopulmonar é caracterizada por tríade clínica que consiste em: 1) doença hepática e/ou hipertensão portal, 2) dilatações vasculares intra-pulmonares, e 3) anormalidades da oxigenação arterial (pressão parcial de oxigênio <70 mm Hg ou gradiente alvéolo-arterial de oxigênio >20 mm Hg). Sua freqüência varia de acordo com os métodos diagnósticos utilizados. OBJETIVOS: Fazer revisão da literatura sobre patogenia, diagnóstico e tratamento da síndrome hepatopulmonar. MÉTODOS: Levantamento no MEDLINE das publicações nacionais e internacionais mais relevantes sobre a síndrome hepatopulmonar. RESULTADOS: A prevalência da síndrome hepatopulmonar varia de 4% a 17,5%, a depender dos critérios diagnósticos utilizados. A doença hepática associada mais comum é a cirrose. O gradiente alvéolo-arterial de oxigênio parece ser o melhor parâmetro para avaliação das anormalidades da oxigenação arterial. Em relação à detecção das dilatações vasculares intra-pulmonares, a ecocardiografia com contraste é o método de escolha, pois é de fácil realização e pode diferenciar as comunicações intra-pulmonares das intra-cardíacas. No tratamento da síndrome hepatopulmonar, poucos relatos bem sucedidos puderam ser reproduzidos e confirmados utilizando terapia farmacológica e/ou radiologia intervencionista. Atualmente, o transplante de fígado é considerado a principal opção terapêutica desses pacientes, com resultados animadores. CONCLUSÕES: A síndrome hepatopulmonar é uma enfermidade freqüente. Exames gasométricos são necessários para o seu diagnóstico. O transplante de fígado é o tratamento de escolha para os portadores da síndrome.

Hepatopulmonary syndrome: angiography and therapeutic embolization

We report a case where an embolization therapy was successfully performed for diffusely dilated pulmonary vessels in a patient with hepatopulmonary syndrome (HPS) as a palliative treatment before liver transplantation. To our knowledge, this therapeutic approach has been tried only for arteriovenous malformation type HPS, and not for diffuse dilatation [Chest 91 (1987) 920].

Retrospective analysis of the results of liver transplantation for adults with severe hepatopulmonary syndrome

The hepatopulmonary syndrome (HPS), consisting of elevated alveolar-arterial oxygen gradient and intrapulmonary vascular abnormalities in the presence of advanced liver disease, is associated with high mortality. Liver transplantation (LT) has been used for the treatment of HPS; however, the success of LT for the treatment of HPS is not uniformly documented. We reviewed our experience over a 5-year period and identified eight adult patients with incapacitating respiratory symptoms compatible with HPS. Inclusion criteria included hypoxemia, normal lung volumes, reduced oxygen diffusing capacity (D(L)CO), and the presence of intrapulmonary shunting. Underlying liver disease was caused by hepatitis C (2 patients), primary biliary cirrhosis (1 patient), cryptogenic cirrhosis (1 patient), alcohol (2 patients), and hepatitis C with alcohol (2 patients). Six out of eight patients required preoperative oxygen support. Severe hypoxemia was present in seven patients (Pa(O2) 51.5 +/- 8.2 mm Hg). Three patients had complicating pulmonary hypertension. All patients exhibited a severely reduced D(L)CO (44.6 +/- 12.2% of predicted value). Six patients were transplanted, with five requiring oxygen support at the time of discharge. Resolution of oxygen dependency occurred in all patients but was delayed in the two patients exhibiting complicating pulmonary hypertension (288.5 +/- 37.4 v 53.5 +/- 35.7 days). All patients exhibited O2 saturations greater than 98% on room air. Currently, three patients are alive and off oxygen. The current report documents successful resolution of hypoxemia after LT in this pilot cohort. This supports the newly implemented United Network for Organ Sharing (UNOS) criteria, that LT for HPS may be extended to include patients with Pa(O2) < 60 mm Hg.

The hepatopulmonary syndrome

The hepatopulmonary syndrome is a triad of liver disease, increased alveolar-arterial oxygen gradient and intrapulmonary vascular dilatations. Manifestations include orthodeoxia, platypnoea and hyperdynamic circulation. Intrapulmonary vascular abnormalities, perhaps mediated by nitric oxide, cause hypoxaemia by shunting, a perfusion-diffusion defect, and ventilation-perfusion mismatching. Contrast-enhanced echocardiography is the method of choice for demonstrating pulmonary vascular abnormalities, although perfusion lung scanning is a more specific and sensitive test. Angiography is best reserved for patients with poor response to 100% oxygen and defines whether vascular dilatations are of the diffuse 'spongy' type or, less commonly, discrete arteriovenous communications amenable to embolization. About 80% of patients with the hepatopulmonary syndrome eventually have improved oxygenation after liver transplantation, thereby making worsening hypoxaemia the primary indication for transplantation in many instances. Nevertheless, severe hypoxaemia carries a peri-operative mortality of 30% and reliable predictors of successful outcome after transplantation remain to be determined.

The hepatopulmonary syndrome

The hepatopulmonary syndrome is a disease entity seen in association with liver failure and other disease entities. It is a devastating consequence of liver failure that results in a significant morbidity for affected patients. Currently, there are no identified medications that ameliorate the symptoms of hypoxemia in this disease state. Recent research, however, has begun to unravel the pathobiology of the vascular dilations that arise in the lungs of patients with liver failure. In this article, a compendium of current knowledge is presented, as well as the contemporary methods for identifying and treating patients.

Transjugular intrahepatic portosystemic shunt: a successful treatment for hepatopulmonary syndrome

Hepatopulmonary syndrome is a well described complication of chronic liver disease. Though uncommon, it carries a high morbidity and mortality. The pathogenesis of the syndrome has not been clearly defined. Portal hypertension seems to play a crucial role in the pathogenesis of the syndrome, probably by enhancing nitric oxide production. As yet, no pharmacological therapy has been proven effective. Many reports of successful reversal of the syndrome after liver transplantation have been published. We report a patient with hepatopulmonary syndrome who showed a significant and durable (4 months') improvement in his symptoms, arterial oxygenation, and intrapulmonary shunts, as calculated by radionuclide studies after transjugular intrahepatic portosystemic shunt placement. Transjugular intrahepatic portosystemic shunt may represent a durable treatment option for patients with hepatopulmonary syndrome.

Hepatopulmonary syndrome. A pulmonary vascular complication of liver disease

Hepatopulmonary syndrome is part of the spectrum of pulmonary vascular disorders seen in advanced liver disease. The pathophysiology of these entities likely is dependent on the degree of pulmonary vasoconstriction or vasodilation that occurs. Our understanding of hepatopulmonary syndrome has helped further our knowledge of the interaction of the liver and the lung. Advances in the management of this disorder, especially liver transplantation, finally have allowed us to offer some hope to patients with this disease.

Mechanisms of gas exchange impairment in patients with liver cirrhosis

This article reviews the basic pathophysiologic mechanisms underlying the abnormal pulmonary gas exchange often seen in patients with cirrhosis. To summarize, the following keypoints seem appropriate: (1) Patients with cirrhosis have a low pulmonary vascular tone characterized by a poor or absent hypoxic pressor response. This results in a marked dilation of the pulmonary vasculature. (2) This abnormal pulmonary vascular tone, independently of airway disease, causes VA/Q mismatch and mild to moderate hypoxemia. Yet, as liver disease progresses and hepatocellular function deteriorates, more severe degrees of intrapulmonary shunt emerge and, probably, O2 diffusion limitation ensues, causing severe respiratory failure (see Table 1). (3) At rest, the high cardiac output and minute ventilation of cirrhosis minimize the degree of arterial hypoxemia that otherwise would be expected from the observed degree of both VA/Q inequality and intrapulmonary shunt. During exercise, the relative "normalization' (with respect to metabolic demands) of the hemodynamic and ventilatory status of the patient explains the fall in PaO2. (4) A clear pathogenic mechanism of these pathophysiologic abnormalities is still lacking, although available evidence suggests that both the liver and the endothelial cells may play a pivotal role in the regulation of the pulmonary vascular tone in these patients. (5) To date, no pharmacologic intervention has been effective in treating hypoxemia in these patients. Yet liver transplantation helps in most of them. This observation reinforces the functional nature of the gas exchange abnormalities of cirrhosis.

Hepatopulmonary syndrome: what are we learning from interventional radiology, liver transplantation, and other disorders?

Interventional radiology (pulmonary angiography, coil embolotherapy, and TIPS) in patients with HPS seems to provide both diagnostic data and therapeutic results of clinical importance. The case report by Riegler et al. is instructive and emphasizes the need for further prospective study to analyze the successes and failures in terms of measurable clinical variable in a procedure such as TIPS. The resolution of hypoxemia following liver transplantation and careful patient selection offers hope to patients with severe, debilitating oxygenation abnormalities caused by HPS.

Transjugular intrahepatic portosystemic shunt improves oxygenation in hepatopulmonary syndrome

Hepatopulmonary syndrome is a complication of chronic liver disease in which arterial hypoxemia results from abnormalities in pulmonary blood flow. Severe hypoxemia can lead to clinical deterioration and death. Although the etiology is unknown, portal hypertension seems to be an important factor in the development of hepatopulmonary syndrome. No effective pharmacological therapy has been identified, but liver transplantation may be curative. Arterial hypoxemia may complicate transplant surgery, however, and resolution of the syndrome after liver transplantation is performed may be delayed. In addition, it seems that complete reversal of oxygenation abnormalities after liver transplantation is performed is unpredictable. We described a patient with hepatopulmonary syndrome who noted improvement in symptoms of dyspnea after the placement of a transjugular intrahepatic portosystemic shunt. Arterial oxygenation and calculated shunt fraction improved significantly during the follow-up period, and liver transplantation was subsequently performed without difficulty. Portal decompression using transjugular intrahepatic portosystemic shunt may represent a palliative therapy for hepatopulmonary syndrome in patients awaiting liver transplantation.