Hepatopulmonary syndrome in patients with chronic liver disease: role of pulse oximetry

Hepatopulmonary Syndrome: A Comprehensive Review

Hepatopulmonary syndrome (HPS) is defined by abnormally dilated blood vessels and shunts within the lungs, leading to impaired oxygen exchange. This condition results from intricate interactions between the liver, the gastrointestinal system, and the lungs. This complex system primarily affects pulmonary endothelial, immunomodulatory, and respiratory epithelial cells. Consequently, this contributes to pathological pulmonary changes characteristic of HPS. A classification system based on the severity of oxygen deficiency has been proposed for grading the physiological dysfunction of HPS. Contrast-enhanced echocardiography is considered the primary radiological evaluation for identifying abnormal blood vessel dilations within the lungs, which, combined with an elevated alveolar-arterial gradient, is essential for making the diagnosis. Liver transplantation is the sole effective definitive treatment that can reverse the course of the condition. Despite often being symptomless, HPS carries a significant risk of mortality before transplantation, regardless of the severity of liver disease. Meanwhile, there is varying data regarding survival rates following liver transplantation. The adoption of the model for end-stage liver disease (MELD) standard exception policy has notably improved the results for individuals with HPS compared to the period before MELD was introduced. This review offers a summary of the present understanding, highlighting recent advancements in the diagnosis and treatment of HPS. Furthermore, it aims to augment comprehension of the condition's fundamental mechanisms through insights derived from experimental models and translational research.

Hepatopulmonary syndrome: An update

Hepatopulmonary syndrome (HPS) is characterized by defects in oxygenation caused by intra-pulmonary vasodilation occurring because of chronic liver disease, portal hypertension, or congenital portosystemic shunts. Clinical implications of portal hypertension are very well-known, however, awareness of its effect on multiple organs such as the lungs are less known. The presence of HPS in chronic liver disease is associated with increased mortality. Medical therapies available for HPS have not been proven effective and definitive treatment for HPS is mainly liver transplantation (LT). LT improves mortality for patients with HPS drastically. This article provides a review on the definition, clinical presentation, diagnosis, and management of HPS.

Comparison of Two Diagnostic Criteria for Hepatopulmonary Syndrome-High Prevalence in Biliary Atresia

OBJECTIVES

There is lack of clarity regarding the exact prevalence of hepatopulmonary syndrome (HPS) in pediatric liver diseases owing to lack of standardized diagnostic criteria. Thus, we aimed to do a comparative study of HPS with respect to its prevalence using the available diagnostic criteria.

METHODS

All consecutive children with biliary atresia (BA) and other chronic liver diseases (CLDs) were studied. Prevalence of HPS was compared using the 2 available criteria: demonstration of intrapulmonary vascular dilatation along with either alveolar-arterial oxygen difference (P [A-a] O2) on arterial blood gas analysis of more than 15 mmHg (criteria 1), or higher than age-appropriate calculated value for P (A-a) O2 (criteria 2).

RESULTS

A total of 42 children in BA group and 62 in the non-BA CLD group were included. Using the criteria 1, the prevalence of HPS was 42.3%: 57.1% in the BA group and 32.2% in the CLD group, whereas using criteria 2, the prevalence was 48.1%: 61.9% in the BA group and 38.7% in the CLD group. Criteria 2 diagnosed 6 additional patients with HPS compared to criteria 1 (P value 0.405). BA subjects had higher risk (2.9-3 folds) of developing HPS compared to other CLDs.

CONCLUSION

There is high prevalence of HPS in pediatric liver disease subjects. Age-appropriate formula for HPS diagnosis may be better applicable in pediatric population. BA subjects have a higher risk of developing HPS compared to other CLDs overall, irrespective of the severity of liver disease and/or portal hypertension.

Pulmonary manifestations of chronic liver disease: a comprehensive review

Hepatopulmonary syndrome (HPS) and porto-pulmonary hypertension (PoPH) represent relatively common pulmonary vascular complications of advanced liver disease. Despite distinct differences in their pathogenetic background, both clinical states are characterized by impaired arterial oxygenation and limited functional status, and are associated with increased pre-transplantation mortality. Accumulation of ascitic fluid in the pleural cavity, known as hepatic hydrothorax (HH), is another frequent manifestation of decompensated cirrhosis, which may cause severe respiratory dysfunction, depending on the volume of the effusion, the rapidity of its development and its resistance to therapeutic measures. Orthotopic liver transplantation constitutes the only effective treatment able to resolve the pulmonary complications of liver disease. A prioritization policy for liver transplantation has evolved over the past years regarding advanced stages of HPS, yielding favorable outcomes regarding post-transplantation survival and HPS resolution. In contrast, severe PoPH is associated with poor post-transplantation survival. Hence, liver transplantation is recommended only for patients with PoPH and an acceptable reduction in pulmonary pressure values, after receiving PoPH-targeted vasodilating therapy. This review focuses on basic pathogenetic and diagnostic principles and discusses the current therapeutic approaches regarding HPS, PoPH, and HH.

Impact of liver damage on blood-borne variables and pulmonary hemodynamic responses to hypoxia and hyperoxia in anesthetized rats

BACKGROUND

Liver disorders may be associated with normal pulmonary hemodynamic, hepatopulmonary syndrome (HPS), or portopulmonary hypertension (POPH). In this study, we aimed to investigate the effect of the severity of liver dysfunctions on blood-borne variables, and pulmonary hemodynamic during repeated ventilation with hyperoxic and hypoxic gases.

METHODS

Female Sprague Dawley rats were assigned into four groups of Sham (n = 7), portal vein ligation (PPVL, n = 7), common bile duct ligation (CBDL, n = 7), and combination of them (CBDL+ PPVL, n = 7). Twenty-eight days later, right ventricular systolic pressure (RVSP) and systemic blood pressure were recorded in anesthetized animals subjected to repeated maneuvers of hyperoxia (O₂ 50%) and hypoxia (O₂ 10%). Besides, we assessed blood parameters and liver histology.

RESULTS

Liver histology score, liver enzymes, WBC and plasma malondialdehyde in the CBDL+PPVL group were higher than those in the CBDL group. Also, the plasma platelet level in the CBDL+PPVL group was lower than those in the other groups. On the other hand, the serum estradiol in the CBDL group was higher than that in the CBDL+PPVL group. All the above parameters in the PPVL group were similar to those in the Sham group. During ventilation with hyperoxia gas, RVSP in the CBDL+PPVL group was higher than the ones in the other groups, and in the CBDL group, it was more than those in the PPVL and Sham groups. Hypoxic pulmonary vasoconstriction (HPV) was not detected in both CBDL+PPVL and CBDL groups, whereas, it retained in the PPVL group.

CONCLUSION

Severe liver damage increases RVSP in the CBDL+PPVL group linked to the high level of ROS, low levels of serum estradiol and platelets or a combination of them. Furthermore, the high RVSP at the noted group could present a reliable animal model for POPH in female rats.

Review article: Update on current and emergent data on hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is a frequent pulmonary complication of end-stage liver disease, characterized by impaired arterial oxygenation induced by intrapulmonary vascular dilatation. Its prevalence ranges from 4% to 47% in patients with cirrhosis due to the different diagnostic criteria applied among different studies. Nitric oxide overproduction and angiogenesis seem to be the hallmarks of a complicated pathogenetic mechanism, leading to intrapulmonary shunting and ventilation-perfusion mismatch. A classification of HPS according to the severity of hypoxemia has been suggested. Contrast-enhanced echocardiography represents the gold standard method for the detection of intrapulmonary vascular dilatations which is required, in combination with an elevated alveolar arterial gradient to set the diagnosis. The only effective treatment which can modify the syndrome’s natural history is liver transplantation. Although it is usually asymptomatic, HPS imparts a high risk of pretransplantation mortality, independently of the severity of liver disease, while there is variable data concerning survival rates after liver transplantation. The potential of myocardial involvement in the setting of HPS has also gained increasing interest in recent research. The aim of this review is to critically approach the existing literature of HPS and emphasize unclear points that remain to be unraveled by future research.

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.

Ventilatory support and hospital stay after liver transplant in cirrhotic patients with hepatopulmonary syndrome

Objective

To compare mechanical ventilation time, need for non-invasive ventilation, length of intensive care unit stay, and hospital stay after liver transplant in cirrhotic patients with and with no diagnosis of hepatopulmonary syndrome.

Methods

This was a prospective cohort study with a convenience sample of 178 patients (92 with hepatopulmonary syndrome) who were diagnosed as alcoholic or hepatitis C virus cirrhosis. The statistical analysis included Kolmogorov-Smirnov test and Students t test. Data were analyzed using SPSS version 16.0, and p values <0.05 were considered significant.

Results

Out of 178 patients, 90 underwent transplant (48 with no hepatopulmonary syndrome). The Group diagnosed with Hepatopulmonary Syndrome had longer mechanical ventilation time (19.5±4.3 hours versus 12.5±3.3 hours; p=0.02), an increased need for non-invasive ventilation (12 versus 2; p=0.01), longer intensive care unit stay (6.7±2.1 days versus 4.6±1.5 days; p=0.02) and longer hospital stay (24.1±4.3 days versus 20.2±3.9 days; p=0.01).

Conclusion

Cirrhotic patients Group diagnosed with Hepatopulmonary Syndrome had higher mechanical ventilation time, more need of non-invasive ventilation, as well as longer intensive care unit and hospital stay.

Hepatopulmonary Syndrome and Liver Transplantation: A Recent Review of the Literature

A severe and common pulmonary vascular complication of liver disease is hepatopulmonary syndrome (HPS). It is a triad of liver dysfunction and/or portal hypertension, intrapulmonary vascular dilatations, and increased alveolar-arterial oxygen gradient. Prevalence varies according to various study groups from 4%-47%. While the most common presenting symptom of HPS is dyspnea, it is usually asymptomatic, and thus all liver transplant candidates should be screened for its presence. Pulse oximetry is a useful screening method, but arterial blood gas examination is the gold standard. If there is an abnormal P (A-a)O2 gradient, microbubble transthoracic echocardiography should be done for diagnosis. Outcome is unpredictable, and there is currently no effective medical therapy. The only effective therapy is considered to be liver transplantation. Complete resolution of HPS after liver transplantation is seen within a year in most HPS patients.

Cirrhotic Multiorgan Syndrome

Patients with cirrhosis and portal hypertension are at an increased risk of the development of circulatory dysfunction that may potentially result in multiple organ failure. Apart from the liver, this may involve the heart, lungs, kidneys, the immune system, the adrenal glands, and other organ systems. As the disease progresses, the circulation becomes hyperdynamic, and signs of cardiac, pulmonary, and renal dysfunction are observed, in addition to reduced survival. Infections and an altered cardiac function known as cirrhotic cardiomyopathy may be precipitators for the development of other complications such as hepatorenal syndrome. In patients with chronic organ dysfunction, various precipitating events may induce an acute-on-chronic renal failure and acute-on-chronic liver failure that negatively affect the prognosis. Future research on the pathophysiologic mechanisms of the complications and the precipitating factors is essential to understand the basics of the treatment of these challenging conditions. The aim of the present review is to focus on the development and precipitating factors of various organ failures in patients with decompensated cirrhosis.

Hepatopulmonary Syndrome

Hepatopulmonary syndrome (HPS) is a pulmonary complication observed in patients with chronic liver disease and/or portal hypertension, attributable to an intrapulmonary vascular dilatation that may induce severe hypoxemia. Microvascular dilation and angiogenesis in the lung have been identified as pathologic features that drive gas exchange abnormalities in experimental HPS. Pulse oximetry is a useful screening test for HPS, which can guide subsequent use of arterial blood gases. Contrast-enhanced echocardiography, perfusion lung scanning, and pulmonary arteriography are three currently used diagnostic imaging modalities that identify the presence of intrapulmonary vascular abnormalities. The presence of HPS increases mortality and impairs quality of life, but is reversible with liver transplantation. No medical therapy is established as effective for HPS. At the present time, liver transplantation is the only available treatment for HPS.

Hepatopulmonary syndrome and portopulmonary hypertension: recent knowledge in pathogenesis and overview of clinical assessment

Hepatopulmonary syndrome and portopulmonary hypertension are cardiopulmonary complications, which are not infrequently seen in patients with liver disease and/or portal hypertension. These entities are both clinically and pathophysiologically different: the hepatopulmonary syndrome is characterized by abnormal pulmonary vasodilation and right-to-left shunting resulting in gas exchange abnormalities, whereas portopulmonary hypertension is caused by pulmonary artery vasoconstriction leading to hemodynamic failure. As both hepatopulmonary syndrome and portopulmonary hypertension are associated with significantly increased morbidity and mortality, and as these patients are commonly asymptomatic, all liver transplantation candidates should be actively screened for the presence of these two complications. The aim of is this review is to provide an overview on the hepatopulmonary syndrome and portopulmonary hypertension with primary focus on diagnosis and recent knowledge regarding pathogenesis and therapeutic targets.

Role of angiogenic factors/cell adhesion markers in serum of cirrhotic patients with hepatopulmonary syndrome

BACKGROUND & AIMS

Hepatopulmonary syndrome is a complication of chronic liver disease resulting in increased morbidity and mortality. It is caused by intrapulmonary vascular dilations and arteriovenous connections with devastating influence on gas exchange. The pathogenesis is not completely understood but evidence mounts for angiogenesis. Aims of this study were to identify angiogenic factors in serum of patients with hepatopulmonary syndrome and to study the possibility to predict its presence by these factors.

METHODS

Multiplex assays were used to measure the concentration of angiogenic factors in patients with (n = 30) and without hepatopulmonary syndrome (n = 30). Diagnosis was based on the presence of gas exchange abnormality and intrapulmonary vasodilations according to published guidelines.

RESULTS

Patients with and without hepatopulmonary syndrome had similar MELD scores (median: 11.2 vs. 11.6; P = 0.7), Child-Pugh score (P = 0.7) and PaCO2 values (median: 35 vs. 37; P = 0.06). PaO2 and P(A-a) O2 gradient were significantly different (respectively median of 80 vs. 86, P = 0.02; and 24 vs. 16, P = 0.004). Based on area under the curve (AUC) data and P-values, the best predictors were vascular cell adhesion molecule 1 (VCAM1) (AUC = 0.932; P < 0.001) and intercellular adhesion molecule 3 (ICAM3) (AUC = 0.741; P = 0.003). Combining these factors results in an AUC of 0.99 (after cross-validation still 0.99).

CONCLUSIONS

VCAM1 and ICAM3 might be promising biomarkers for predicting hepatopulmonary syndrome. Combining these factors results in an AUC of 0.99 and a negative predictive value of 100%. Determining the concentration of these biomarkers might be a screening method to detect hepatopulmonary syndrome. The use of these biomarkers should be validated in larger groups of patients.

[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.

Serial pulse oximetry in hepatopulmonary syndrome

BACKGROUND/AIM

The natural history of hepatopulmonary syndrome (HPS) is poorly characterized and how hypoxemia develops and progresses over time is unclear. We evaluated oxygenation over time in advanced liver disease patients with and without HPS using serial pulse oximetry.

METHODS

Data from a prospective cohort of patients evaluated for liver transplantation were analyzed. All patients with significant cardiopulmonary disease were excluded and patients with and without HPS were compared. Arterial oxygen saturation measurements with pulse oximetry (SpO(2)) were recorded serially from initial evaluation until transplantation or last clinic visit on record. Patients with SpO(2) measurements at ≥ 2 visits were included.

RESULTS

A total of 22 HPS patients were compared to 32 non-HPS patients (18 with intrapulmonary vasodilation on contrast echocardiography, CE) over a mean duration of 20 months and 4 SpO(2) measurements. HPS patients had lower SpO(2) at baseline (96.8 vs. 98.4%, P = 0.02) and at end of follow-up (95.8 vs. 98.2%, P = 0.02), and were more likely to have a ≥ 2% reduction (P = 0.04) and faster decline in SpO(2) as compared to non-HPS patients (F = 2.2, P = 0.04). HPS patients with lower SpO(2) and/or PO(2) at baseline appeared more likely to worsen over time. There was no difference in SpO(2) over time between the 2 non-HPS subgroups (- or +CE).

CONCLUSIONS

HPS patients have a significant decline in SpO(2) over time compared to non-HPS patients, and therefore, pulse oximetry may be useful for monitoring cirrhotics for development or worsening of HPS. Presence of intrapulmonary vasodilation in the absence of hypoxemia does not appear to affect SpO(2) over time.

(99m)Technetium-macroaggregated albumin perfusion lung scan versus contrast enhanced echocardiography in the diagnosis of the hepatopulmonary syndrome in children with chronic liver disease

BACKGROUND AND AIMS

The hepatopulmonary syndrome (HPS) is a triad of advanced chronic liver disease (CLD), arterial hypoxemia and intrapulmonary arteriovenous shunting in the absence of a primary cardiopulmonary disease. HPS has been more frequently reported in adults than in children with no data on its prevalence in children with CLD. The aim of this study was to detect the prevalence of the HPS in a cohort of children with CLD because of chronic hepatitis B and/or C virus infection, schistosomiasis as well as inborn metabolic errors. We also aimed to evaluate the role of Technetium labeled macroaggregated albumin (Tc--MAA) perfusion lung scan versus contrast enhanced echocardiography (CEE) with intravenous injection of agitated saline in the diagnosis and quantification of intrapulmonary shunts and their relationship to important clinical and laboratory findings.

METHODS

Forty Egyptian children (22 males) were investigated. Their ages ranged from 5 to 12 years (with a mean of 9.5 years). Twenty individuals proved to have cirrhosis.

RESULTS

Blood gas determination revealed more significant arterial hypoxemia in cirrhotics than noncirrhotics both under room air and after breathing 100% oxygen for 15 mins. CEE showed comparable cardiac measurements in cirrhotic and noncirrhotic patients, and diagnosed intrapulmonary shunts in three hypoxemic cirrhotic patients; whereas Tc--MAAperfusion lung scan diagnosed shunts in seven patients (five of them cirrhotic). The presence of shunts was significantly correlated with the duration of CLD, clinical findings, presence of cirrhosis and porto-systemic collaterals. We calculated for each patient a shunt index (SI) by the formula: (activity outside thorax/activity outside plus inside thorax) 100; and an SI value of 0.278 was found to be a cutoff value for shunt detection. All patients with SI above this value had shunting associated with hypoxemia and all patients with SI below this value had no hypoxemia (specificity 100%).

CONCLUSION

Arterial hypoxemia and intrapulmonary shunts were diagnosed in 17.5% of this cohort of children with cirrhotic or noncirrhotic CLD representing the classic HPS. Tc--MAA perfusion lung scan was more sensitive than CEE in detection of intrapulmonary shunts. SI cutoff value of 0.278 was found to be highly specific for shunt detection and we recommend its validation in further studies.

Pulmonary dysfunction and hepatopulmonary syndrome in cirrhosis and portal hypertension

BACKGROUND

Pulmonary dysfunction including the hepatopulmonary syndrome (HPS) is an important complication to cirrhosis and portal hypertension. However, the precise relation to liver dysfunction and the prevalence of HPS are unclear.

AIMS

We therefore aimed to assess (i) the prevalence of HPS in consecutive alcoholic cirrhotic patients, (ii) the degree of pulmonary dysfunction in relation to liver function and (iii) the response of a 100% oxygen test on cardiopulmonary and peripheral oxygenation.

METHODS

Fifty patients with cirrhosis and 12 matched healthy controls were entered in this study. All underwent haemodynamic and pulmonary investigations [lung diffusing capacity for carbon monoxide (DLCO), contrast-enhanced echocardiography and detection of extrapulmonary shunt fraction]. A 100% oxygen test was performed with the assessment of arterial oxygen tension (PaO(2)), the alveolar-arterial oxygen gradient (AaPO(2)) and peripheral transcutaneous oxygen tension (tcPO(2)).

RESULTS

The prevalence of HPS was 10%. PaO(2) and DLCO were reduced in 32 and 72% and AaPO(2), was increased in 60% of the patients respectively. DLCO correlated with indicators of liver dysfunction (galactose elimination capacity, P<0.01, indocyanine green clearance, P<0.001), portal hypertension (post-sinusoidal resistance, P<0.01) and central hypovolaemia (central and arterial blood volume, P<0.01). After 100% oxygen inhalation, the changes in PaO(2), AaPO(2), tcPO(2) and heart rate were abnormal in the patients compared with controls (P<0.02).

CONCLUSIONS

Pulmonary dysfunction in alcoholic cirrhosis is common and relates to different aspects of liver dysfunction, whereas the prevalence of HPS is low. The haemodynamic response to oxygen inhalation is clearly impaired and HPS and pulmonary dysfunction seem to be caused by different pathophysiological mechanisms.

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.

[Hepatopulmonary syndrome in patients with advanced hepatic disease: study of a series of 24 cases]

BACKGROUND AND OBJECTIVE

To describe the characteristics observed in patients diagnosed of hepatopulmonary syndrome (HPS) waiting for orthotopic liver transplantation and those who underwent liver trasplantation.

PATIENTS AND METHOD

An observational prospective descriptive study was carried out of patients waiting for liver transplantation in whom data of liver illness and lung function tests were analyzed.

RESULTS

107 patients of 53.69 years average age were studied (7.7 standard deviation). 24 of them (22.4%) had criteria of HPS. Ortodeoxia was present in the 34% of cases. The lung function tests were normal. In the comparative study between patients with HPS and no HPS, differences in diffusion were found (7.1 vs. 8.6 mmol/min/kPa; p = 0.04), as well as in the shunt (8% vs. 5.3%; p = 0.05) and the forced expiratory volume in one second (2,390 vs. 2,743 ml; p = 0.03). Seven patients were transplanted with correction of oxygenation and vascular dilatations in all of them.

CONCLUSIONS

HPS is a frequent illness in patients waiting for orthotopic liver transplantation. The main alteration in the blood oxygenation seems owe to shunt, and the diffusion tests is the analysis that could best differentiate patients with HPS. Orthotopic liver transplantation corrects the syndrome in all cases.

Pretransplant risk factors and optimal timing for living-related liver transplantation in biliary atresia: experience of one Japanese children's hospital and transplantation center

BACKGROUND/PURPOSE

Although living-related liver transplantation (LRLT) is effective for patients with biliary atresia (BA) after a failed Kasai operation, the pretransplant factors affecting post-LRLT mortality and the optimal timing of the procedure remain unclear.

METHOD

A retrospective review of 27 patients with BA after a failed Kasai operation (median age, 22 months; range, 6-237 months) who received LRLT from 1994 to 2005 was done. The clinical characteristics at the time of the pre-LRLT assessment of those who did and did not survive were compared. A simple regression analysis and receiver operating characteristic analysis were done to correlate the clinical data.

RESULTS

Among the 27 patients, 4 patients died within 1 year post-LRLT. The significant factors affecting posttransplant death were hepatopulmonary syndrome (HPS), age at LRLT, and graft-to-recipient weight ratio. The arterial blood gas analysis of HPS patients showed that there was a significant negative correlation between the SaO(2) value on room air and the intrapulmonary shunt ratio. The receiver operating characteristic analysis of age at LRLT showed that the optimal cutoff point was 103 months of age.

CONCLUSION

Older children with HPS or a lower graft-to-recipient weight ratio are not ideal candidates for LRLT. The correlation between the shunt ratio and SaO(2) suggests that HPS could be detected early using pulse oximetry.

Preoperative evaluation of patients with liver disease

Patients with end-stage liver disease often undergo surgery for indications other than liver transplantation. These patients have an increased risk of morbidity and mortality that is related to their underlying liver disease. Assessments of surgical risk provide a basis for discussion of risks and benefits, treatment decision making, and for optimal management of patients for whom surgery is planned. The most useful indicators of surgical risk are indices that predict advanced disease, such as the Child-Turcotte-Pugh score, or those that predict prognosis, such as the Model for End-stage Liver Disease score. Careful preoperative risk assessment, patient selection, and management of various manifestations of advanced disease might decrease morbidity and mortality from nontransplant surgery in patients with liver disease.