肝肺综合征诊治的研究进展

肝肺综合征(hepatopulmonary syndrome,HPS)是指以肝脏疾病为基础病因,以肺内血管扩张和肺内动静脉分流导致呼吸困难和低氧血症的疾病。近年来,尽管对HPS的病理生理和发病机制进行了大量研究,但目前仍无特效药物治疗,而肝移植仍然是唯一有效的治疗方法。本文重点介绍肝肺综合征的发病机理、临床表现、诊断、治疗以及最新的研究进展。     

肝肺综合征的研究现状

肝肺综合征（hepatopulmonmy syndrome,HPS）是在慢性肝病和（或）门静脉高压基础上出现肺血管扩张、动脉血氧合功能异常,临床上以肝功能不全、肺血管扩张、进行性呼吸困难、低氧血症为主要表现,并具有慢性肝病、肺泡动脉血氧分压差[P（A-a）2]增大或动脉血氧分压（PaO2）降低和肺内血管扩张的临床三联症[1].HPS起病隐匿,临床症状不典型,且发病机制复杂,检查诊断困难,无有效治疗手段,导致其临床预后不良,本文就HPS的病因、发病机制、临床表现及诊断与治疗的研究进展作一综述,供临床诊疗参考.     

气体信号分子与急性肺损伤

急性肺损伤(acute lung injury,ALI)由多种炎性介质及效应细胞共同参与,并呈级联放大的瀑布样炎症继发性损伤与弥漫性肺实质损伤,且可进一步发展为急性呼吸窘迫综合征(ARDS).ALI/ARDS发病机制复杂[1],病死率高,已成为临床危重病学研究的热点和难点,故探寻新的治疗方法显得尤为重要.内源性气体信号分子一氧化氮(NO)、一氧化碳(CO)和硫化氢(H2S)的发现为肺损伤等疾病的研究提供了一个全新的思路.研究发现它们均参与了ALI的发病且对ALI具有调节作用.二氧化硫(SO2)是最近提出的一种新型气体信号分子,在心血管系统中发挥广泛的生物学活性[2].     

肝肺综合征研究进展

肝肺综合征(hepato-pulmonary syndrome,HPS)是在慢性肝病和(或)门脉高压的基础上出现肺内血管异常扩张、气体交换障碍、动脉血氧合作用异常,导致低氧血症及一系列的病理生理变化和临床表现,是终末期肝脏病的严重肺部并发症。动物实验表明肺微血管扩张、血管新生和血管内单核巨噬细胞聚集是导致气体交换异常的主要原因,但具体机制仍不明确。目前HPS尚缺乏有效的治疗药物,肝移植仍是最有效的治疗方法。本研究将重点讨论HPS的发病机制和临床诊治相关的新进展。     

肝肺综合征肝移植术后早期并发症的护理

肝肺综合征(hepatopulmonary syndrome,HPS)是指肝功能不全引起肺血管扩张、肺气体交换障碍导致低氧血症及其一系列病理生理变化和临床表现,多见于肝硬化病人.     

肝肺综合征的诊治

肝肺综合征(hepatopulmonary syndrome,HPS)是一种与肝病有关的肺血管扩张致动脉氧合功能降低的一种综合征,其发生主要与肺循环异常有关,定义为在肝病和(或)门静脉高压症进展的基础上出现肺血管扩张、低氧血症.     

肝硬化患者肝肺综合征的观察及护理

肝硬化患者肝肺综合征的观察及护理第三军医大学大坪医院野战外科研究所消化科（重庆４０００４２）李霞肝肺综合征（Ｈｅｐａｔｏｐｕｌｍｏｎａｒｙｓｙｎｄｒｏｍｅ，ＨＰＳ）是指由肝脏疾病导致肺血管扩张，肺部气体交换障碍，引起不同程度的动脉血氧分压下降，并出现...     

肝肺综合征肝移植术后早期并发症的护理

肝肺综合征（hepatopulmonary syndrome，HPS）是指肝功能不全引起肺血管扩张、肺气体交换障碍导致低氧血症及其一系列病理生理变化和临床表现。多见于肝硬化病人。HPS在肝硬化中的发病率为5％～29％，如不进行肝移植，病死率高达41％。有研究表明，HPS病人肺内血管扩张，肺内广泛右向左分流在移植术后数周内可持续存在，     

对基层医院肝肺综合征诊断的探讨

肝肺综合征( hepatopulmonary syndrome, HPS)为肝功能不全、肺血管扩张和低氧血症综合征,至少有三分之一的慢性肝病患者易出现此综合征 [1].作者总结自 2000年 1月～ 2001年 12月在本科住院的、资料完整的肝肺综合征患者 10例,对基层医院诊断肝肺综合征的方法做一探讨,供同道参考.     

肝肺综合征63例临床回顾性分析

肝肺综合征 (Hepatopulmonarysyndrome ,HPS)是指肝病终末期发生的肺血管异常引起的血氧合功能障碍 ,为肝功能不全、肺血管扩张和低氧血症综合征[1 ] 。本文根据我院近几年来收集的 63例肝肺综合征的临床资料进行回顾性分析 ,以探讨肝肺综合征的临床特点和预后 ,为临床诊治提供     

Pulmonary infarction after liver transplant and previous hepatopulmonary syndrome

We describe the case of a 36-year-old woman with previous hepatopulmonary syndrome in which a focal pulmonary lesion developed after liver transplantation. Thoracoscopic resection showed a pulmonary infarction of the superior segment of the right lower lobe. The patient recovered and had no further thrombotic events after 2 years of follow-up. The pulmonary vascular changes observed during hepatopulmonary syndrome may predispose patients to the development of pulmonary infarction.     

Hepatopulmonary syndrome-attributed extreme hypoxemia and polycythemia revealing liver cirrhosis

We report an unusual case of severe hepatopulmonary syndrome with previously unrecognized cirrhosis, presenting with acute on chronic dyspnoea, extreme hypoxemia, secondary polycythemia as well as direct identification of arteriovenous communications on computed tomography angiography. Hepatopulmonary syndrome, defined as the combination of hepatopathy, arterial deoxygenation and pulmonary vascular dilatation, is increasingly recognized as a life-threatening complication in advanced liver disease and transplant candidacy. It is usually diagnosed in chronic liver disease patients following pre-transplant evaluation or mild dyspnea investigation. Diagnosis relies on the indirect evidence of pulmonary arteriovenous communications suggested by echocardiography with a bubble study. Clinicians need to be aware of this rare but potential acute presentation at the emergency room.     

Hepatopulmonary syndrome.

The hepatopulmonary syndrome (HPS) is a rare complication of liver cirrhosis and is characterised by the typical triad of liver cirrhosis, arterial hypoxemia, and intrapulmonary vascular dilatation. Except for pleural effusions associated with liver cirrhosis no other disease of the lungs or the heart is detectable. The structural hallmark of HPS is dilatation of pulmonary precapillary vessels which impairs diffusion-perfusion and causes unequal ventilation-perfusion. The diagnosis of HPS is based on PaO2 measurements when breathing room air and 100% oxygen. The increased intrapulmonary vascular diameter allows microbubbles to traverse the lung capillaries when agitated saline is administered intravenously. Only on rare occasions is a patient limited by his pulmonary impairment, the leading morbidity is that of liver disease and its classical complications. Drug therapy is of no proven benefit, oxygen supplementation might improve dyspnea. Vascular embolisation of discrete arteriovenous shunts, if present, or liver transplantation may dramatically improve pulmonary function in selected patients.     

Respiratory dysfunction and pulmonary disease in cirrhosis and other hepatic disorders

End-stage liver disease and its complications are a leading cause of death among adults in the United States, and thousands of patients await liver transplantation. The liver plays a central role in health and homeostasis and thus the diseased liver leads to many deleterious effects on multiple organ systems, including the pulmonary system. We review the general effects of cirrhosis on the respiratory system, including mild hypoxemia, atelectasis, and hepatic hydrothorax. Cirrhosis is associated with 2 unique entities that affect the pulmonary vasculature: hepatopulmonary syndrome and portopulmonary hypertension. Hepatopulmonary syndrome, which is found in approximately 20% of patients awaiting liver transplantation, refers to the triad of hepatic dysfunction, hypoxemia, and intrapulmonary vascular dilations, and responds well to liver transplantation. In portopulmonary hypertension, cirrhosis and portal hypertension lead to pulmonary arterial hypertension, and portopulmonary hypertension has been considered a contraindication for transplantation. Currently, patients must have mild to moderate pulmonary hypertension to be considered for transplantation, and may still require long-term therapy with vasodilators to prevent right-ventricular failure and, consequently, failure of the newly transplanted liver allograft.     

Extracorporeal membrane oxygenation as a bridge to liver transplantation for acute respiratory distress syndrome-induced life-threatening hypoxaemia aggravated by hepatopulmonary syndrome

Introduction

Combined with massive lung aeration loss resulting from acute respiratory distress syndrome, hepatopulmonary syndrome, a liver-induced vascular lung disorder characterized by diffuse or localized dilated pulmonary capillaries, may induce hypoxaemia and death in patients with end-stage liver disease.

Methods

The case of such a patient presenting with both disorders and in whom an extracorporeal membrane oxygenation was used is described.

Results

A 51-year-old man with a five-year history of alcoholic cirrhosis was admitted for acute respiratory failure, platypnoea and severe hypoxaemia requiring emergency tracheal intubation. Following mechanical ventilation, hypoxaemia remained refractory to positive end-expiratory pressure, 100% of inspired oxygen and inhaled nitric oxide. Two-dimensional contrast-enhanced (agitated saline) transthoracic echocardiography disclosed a massive right-to-left extracardiac shunt, without patent foramen ovale. Contrast computed tomography (CT) of the thorax using quantitative analysis and colour encoding system established the diagnosis of acute respiratory distress syndrome aggravated by hepatopulmonary syndrome. According to the severity of the respiratory condition, a veno-venous extracorporeal membrane oxygenation was implemented and the patient was listed for emergency liver transplantation. Orthotopic liver transplantation was performed at Day 13. At the end of the surgical procedure, the improvement in oxygenation allowed removal of extracorporeal membrane oxygenation (Day 5). The patient was discharged from hospital at Day 48. Three months after hospital discharge, the patient recovered a correct physical autonomy status without supplemental O₂.

Conclusions

In a cirrhotic patient, acute respiratory distress syndrome was aggravated by hepatopulmonary syndrome causing life-threatening hypoxaemia not controlled by standard supportive measures. The use of extracorporeal membrane oxygenation, by controlling gas exchange, allowed the performing of a successful liver transplantation and final recovery.     

Type Ⅰ congenital extrahepatic portosystemic shunt treated by orthotopic liver transplantation: A case report

BACKGROUND Congenital extrahepatic portosystemic shunt, also known as Abernethy deformation, is a rare malformation caused by dysplasia in the portal vein system. There are few reports of liver transplantation as a treatment for Abernethy deformation, and our report is the first case in China. This is the second reported case with congenital extrahepatic portosystemic shunt combined with focal nodular hyperplasia and hepatopulmonary treated with liver transplantation.CASE SUMMARY The patient was a 14-year-old girl, diagnosed preoperatively as type Ib Abernethy deformation, intrahepatic multiple space-occupying lesion, and hepatopulmonary syndrome. The patient recovered well after undergoing classic orthotopic liver transplantation. Liver function, pulmonary function, and portal vein computed tomography angiography imaging were reexamined 20 mo postoperatively, and no abnormality was observed.CONCLUSION Liver transplantation is an effective treatment for type I Abernethy deformation combined with focal nodular hyperplasia and hepatopulmonary syndrome.     

Carbon monoxide: a new pharmaceutical agent?

Small amounts of carbon monoxide (CO) are continuously produced in mammals. The intracellular levels of this gaseous molecule can markedly increase under stressful conditions following the induction of heme oxygenases (HO), ubiquitous enzymes responsible for the catabolism of heme. The development of a technology concerning the CO-releasing molecules (CO-RMs) that control the delivery and action of CO under different pathological conditions represents a major step forward in the development of CO-based pharmaceuticals with therapeutic applications. CO is important for the homeostatic control of cardiovascular functions. Abnormal metabolism and function of CO contribute to the pathogenesis and development of hypertension. Another vascular disease in which the role of CO has been evaluated is pulmonary arterial hypertension. Important results have been reported in which CO prevents intimal hyperplasia by arresting hyperproliferative vascular smooth muscle cells as well as increased mobilization and recruitment of bone-marrow-derived progenitor cells. Transplantation has been a field of research, in which most studies have investigated the beneficial properties of CO-RMs. CO gas and CO-RMs have produced promising results in the preservation of organs for transplantation. The anti-inflammatory properties of CO and CO-RMs have been demonstrated in a multitude of animal models of inflammation, suggesting a possible therapeutic application for inflammatory diseases. Despite therapeutic benefit in animal model studies, the efficacy of CO in humans remains unclear. Further studies are expected to better understand the pharmacokinetics as well as long- and short-term effects of CO-RMs.     

Pulmonary arterial hypertension

Pulmonary arterial hypertension is a disease of the small pulmonary arteries characterized by vascular narrowing and increased pulmonary vascular resistance, which eventually leads to right ventricular failure. Vasoconstriction, vascular proliferation, remodeling of the pulmonary vessels, and thrombosis are all contributing factors to the increased vascular resistance seen in this disease. Pulmonary arterial hypertension develops as a sporadic disease (idiopathic), as an inherited disorder (familial), or in association with certain conditions (collagen vascular diseases, portal hypertension, human immunodeficiency virus infection, congenital systemic‐to‐pulmonary shunts, ingestion of drugs or dietary products, or persistent fetal circulation). The pathogenesis of pulmonary arterial hypertension is a complicated, multifactorial process. It seems doubtful that any one factor alone is sufficient to activate the necessary pathways leading to the development of this disease. Rather, clinically apparent pulmonary arterial hypertension most likely develops after a second insult occurs in an individual who is already susceptible owing to genetic factors, environmental exposures, or acquired disorders. Currently, there is no cure for pulmonary arterial hypertension but several novel therapeutic options are now available that can improve symptoms and increase survival.