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

[The Role of the Anaesthesiologist in Liver Transplantation - Preoperative Evaluation]

Preoperative evaluation prior to listing for orthotopic liver transplantation (LT) requires a careful multidisciplinary approach with specialized teams including surgeons, hepatologists and anesthesiologists in order to improve short- and long-term clinical outcomes. Due to inadequate supply of donor organs and changing demographics, patients listed for LT have become older, sicker and share more comorbidities. As cardiovascular events are the leading cause for early mortality precise evaluation of risk factors is mandatory. This review focuses on the detection and management of coronary artery disease, cirrhotic cardiomyopathy, portopulmonary hypertension and hepatopulmonary syndrome in patients awaiting LT. Further insights are being given into scoring systems, patients with Acute-on-chronic-liver-failure (ACLF), frailty, NASH cirrhosis and into psychologic evaluation of patients with substance abuse.

Pulmonary Assessment of the Liver Transplant Recipient

Respiratory symptoms and hypoxemia can complicate chronic liver disease and portal hypertension. Various pulmonary disorders affecting the pleura, lung parenchyma, and pulmonary vasculature are seen in end-stage liver disease, complicating liver transplantation (LT). Approximately 8% of cirrhotic patients in an intensive care unit develop severe pulmonary problems. These disorders affect waiting list mortality and posttransplant outcomes. A thorough history, physical examination, and appropriate laboratory tests help diagnose and assess the severity to risk stratify pulmonary diseases before LT. Hepatopulmonary syndrome (HPS), portopulmonary hypertension (POPH), and hepatic hydrothorax (HH) are respiratory consequences specific to cirrhosis and portal hypertension. HPS is seen in 5-30% of cirrhosis cases and is characterized by impaired oxygenation due to intrapulmonary vascular dilatations and arteriovenous shunts. Severe HPS is an indication of LT. The majority of patients with HPS resolve their hypoxemia after LT. When pulmonary arterial hypertension occurs in patients with portal hypertension, it is called POPH. All other causes of pulmonary arterial hypertension should be ruled out before labeling as POPH. Since severe POPH (mean pulmonary artery pressure [mPAP] >50 mm Hg) is a relative contraindication for LT, it is crucial to screen for POPH before LT. Those with moderate POPH (mPAP >35 mm Hg), who improve with medical therapy, will benefit from LT. A transudative pleural effusion called hepatic hydrothorax (HH) is seen in 5-10% of people with cirrhosis. Refractory cases of HH benefit from LT. In recent years, increasing clinical expertise and advances in the medical field have resulted in better outcomes in patients with moderate to severe pulmonary disorders, who undergo LT.

Quercetin ameliorates acute lung injury in a rat model of hepatopulmonary syndrome

BACKGROUND

Common bile duct ligation (BDL) is a rat experimental model to induce biliary cirrhosis. Lung fibrosis and pulmonary vascular angiogenesis and congestion are the most common complications of biliary cirrhosis that is known as hepatopulmonary syndrome. The aim of the present work is to investigate the acute lung injury in a BDL model and to investigate the possible protective effect of quercetin on this injury.

METHODS

Twenty-four adult male albino rats of the Wister strain (weighing 150-250 g). Animals were divided into 3 groups, with 8 rats each: Group I: Sham-operated group (control). Group II: Bile duct ligation group (BDL) sacrificed after 28 days from the surgery. Group III: Quercetin-treated bile duct ligation group (Q-BDL) was given orally by gastric gavage in a dose of 50 mg/kg/day, starting from the 4th day of the operation until the 28th day. At the end of the experiment, at day 28, all rats were sacrificed. Lung specimens were processed to measure Endothelin B receptor gene expression by PCR, lung surfactant by ELISA, "eNO" s by immunohistochemistry. Histological assessment was done using; H&E, Masson's trichrome, PAS, toluidine blue-stained semi-thin sections, transmission electron microscope. Histomorphometric and statistical studies were done.

RESULTS

BDL group showed significant increase in lung index together with mononuclear cellular infiltration denoting lung inflammatory state. Also, the significant increase in pulmonary endothelial nitric oxide synthase ("eNO" s) area percent and endothelin B receptor (ET_B) gene expression indicates enhanced angiogenesis. Pulmonary surfactant concentration was significantly decreased together with thickening of interalveolar septa denoting lung injury and fibrosis. Quercetin led to significant decrease in lung index, pulmonary "eNO" s area percent, ET_B gene expression and significant increase in pulmonary surfactant concentration. Quercetin treatment improved histological changes and morphometric measurements, limited mononuclear cellular infiltration and decreased perivascular and perialveolar collagen deposition.

CONCLUSION

Quercetin ameliorates the hepatopulmonary syndrome-induced lung injury through its anti-inflammatory, antioxidative and antifibrotic effects.

The Edge of Unknown: Postoperative Critical Care in Liver Transplantation

Perioperative care of patients undergoing liver transplantation (LT) is very complex. Metabolic derangements, hypothermia, coagulopathy and thromboses, severe infections, and graft dysfunction can affect outcomes. In this manuscript, we discuss several perioperative problems that can be encountered in LT recipients. The authors present the most up-to-date information regarding predicting and treating hemodynamic instability, coagulation monitoring and management, postoperative ventilation strategies and early extubation, management of infections, and ESLD-related pulmonary complications. In addition, early post-transplant allograft dysfunction will be discussed.

Hepatopulmonary Syndrome and Portopulmonary Hypertension: Pulmonary Vascular Complications of Liver Disease

Pulmonary vascular disease is a frequent complication of chronic liver disease and portal hypertension, affecting up to 30% of patients. There are two distinct pulmonary vascular complications of liver disease: hepatopulmonary syndrome (HPS) and portopulmonary hypertension (POPH). HPS affects 25% of patients with chronic liver disease and is characterized by intrapulmonary vasodilatation and abnormal arterial oxygenation. HPS negatively impacts quality of life and is associated with a 2-fold increased risk of death compared to controls with liver disease without HPS. Angiogenesis, endothelin-1 mediated endothelial dysfunction, monocyte influx, and alveolar type 2 cell dysfunction seem to play important roles in disease pathogenesis but there are currently no effective medical therapies. Fortunately, HPS resolves following liver transplant (LT) with improvements in hypoxemia. POPH is a subtype of pulmonary arterial hypertension (PAH) characterized by an elevated mean pulmonary arterial pressure and pulmonary vascular resistance in the setting of normal left-sided filling pressures. POPH affects 5% to 6% of patients with chronic liver disease. Although the pathogenesis has not been fully elucidated, endothelial dysfunction, inflammation, and estrogen signaling have been identified as key pathways involved in disease pathogenesis. POPH is typically treated with PAH targeted therapy and may also improve with liver transplantation in selected patients. This article highlights what is currently known regarding the diagnosis, management, pathobiology, and outcomes of HPS and POPH. Ongoing research is needed to improve understanding of the pathophysiology and outcomes of these distinct and often misunderstood pulmonary vascular complications of liver disease. © 2021 American Physiological Society. Compr Physiol 11:1-22, 2021.

Excellent outcomes with liver transplantation in hepatopulmonary syndrome across pre-transplant PaO2 spectrum

Background & Aims

Significantly worse survival has been reported in patients with hepatopulmonary syndrome (HPS) and partial pressure of arterial oxygen (PaO₂) <45 mmHg undergoing liver transplantation. Long-term pre- and post-transplant outcomes based on degree of hypoxaemia were re-examined.

Methods

A retrospective analysis of 1,152 HPS candidates listed with an approved HPS model for end-stage liver disease (MELD) exception was performed. A Fine and Gray competing risks model was utilised to evaluate pre-transplant outcomes for PaO₂ thresholds of <45, 45 to <60, and ≥60 mmHg. Post-transplant survival was analysed using the Kaplan-Meier method.

Results

Patients with a PaO₂ <45 mmHg were significantly more likely to undergo transplantation (hazard ratio [HR] 1.51; 95% CI 1.12-2.03), whereas patients with higher MELD scores had lower hazard of transplant (HR 0.80, 95% CI 0.67-0.95, p = 0.011) and higher hazard of pre-transplant death (HR 2.29, 95% CI 1.55-3.37, p <0.001). Post-transplantation, patients with a PaO₂ <45 mmHg had lower survival (p = 0.04) compared with patients with a PaO₂ ≥45 to <50 mmHg, with survival curves significantly different at 2.6 years (75% survival compared with 86%) and median survival of 11.5 and 14.1 years, respectively. Cardiac arrest was a more likely (p = 0.025) cause of death for these patients. Cardiac arrest incidence in patients who died with a PaO₂ >50 mmHg was 6.2%.

Conclusions

Patients with a PaO₂ <45 mmHg had a significantly higher rate of transplantation, and higher calculated MELD scores were associated with significantly higher pre-transplant mortality. Although post-transplant survival was lower in patients with a PaO₂ <45 mmHg, the median survival was 11.5 years, and survival curves only became significantly different at 2.6 years. This suggests that patients with HPS do benefit from transplantation up to 2-3 years post-transplant regardless of the severity of pre-transplant hypoxaemia.

Lay summary

A total of 1,152 patients with hepatopulmonary syndrome listed for liver transplant were analysed. Patients with a low PaO₂ <45 mmHg had a high likelihood of transplantation. If associated with advanced liver disease, the mortality risk was higher for patients with hepatopulmonary syndrome on the wait list. After liver transplantation, patients with a PaO₂ <45 mmHg had a lower survival, but this only became significant after 2.6 years, and the median survival was 11.5 years. This suggests that patients with hepatopulmonary syndrome do benefit from transplantation.

Anesthetic Management Using Low Fraction of Inspiratory Oxygen for Living Donor Liver Transplantation in a Patient With Hepatopulmonary Syndrome Complicated by Interstitial Pneumonia: A Case Report

BACKGROUND

Hepatopulmonary syndrome frequently complicates end-stage liver disease. It causes hypoxemia and requires oxygen administration. Additionally, interstitial pneumonia causes hypoxemia; however, it is known to be aggravated by high-concentration oxygen administration.

CASE PRESENTATION

A 71-year-old woman with hepatopulmonary syndrome and interstitial pneumonia underwent living donor liver transplantation, requiring conflicting management in terms of the inspiratory oxygen concentration. We achieved a low intraoperative fraction of inspiratory oxygen by increasing the cardiac output with intravenous catecholamines. As a result, the transplanted liver functioned well postoperatively, and the patient was discharged without exacerbation of the interstitial pneumonia.

CONCLUSION

We suggest that patients with hepatopulmonary syndrome complicated with interstitial pneumonia can undergo successful living donor liver transplantation without the use of high inspiratory oxygen concentration by using catecholamines to maintain a high mixed venous oxygen saturation.

Pulmonary Abnormalities in Liver Disease: Relevance to Transplantation and Outcome

Pulmonary disease in liver cirrhosis and portal hypertension (PH) constitutes a challenging clinical scenario and may have important implications with regard to prognosis, liver transplantation (LT) candidacy, and post-LT outcome. Pre-LT evaluation should include adequate screening for pulmonary diseases that may occur concomitantly with liver disease as well as for those that may arise as a complication of end-stage liver disease and PH, given that either may jeopardize safe LT and successful outcome. It is key to discriminate those patients who would benefit from LT, especially pulmonary disorders that have been reported to resolve post-LT and are considered "pulmonary indications" for transplant, from those who are at increased mortality risk and in whom LT is contraindicated. In conclusion, in this article, we review the impact of several pulmonary disorders, including cystic fibrosis, alpha 1-antitrypsin deficiency, hereditary hemorrhagic telangiectasia, sarcoidosis, coronavirus disease 2019, asthma, chronic obstructive pulmonary disease, pulmonary nodules, interstitial lung disease, hepatic hydrothorax, hepatopulmonary syndrome, and portopulmonary hypertension, on post-LT survival, as well as the reciprocal impact of LT on the evolution of lung function.

Inhaled nitric oxide improves the hepatopulmonary syndrome: a physiologic analysis

The hepatopulmonary syndrome (HPS) is defined by liver dysfunction, intrapulmonary vasodilatation and abnormal oxygenation. Hypoxaemia is progressive and liver transplant is the only effective treatment. Severe hypoxaemia is a life-threatening HPS complication, particularly after transplant. We evaluated gas-exchange and haemodynamic effects of invasive therapies in a consecutive sample of 26 pre-transplant patients. Inhaled nitric oxide significantly improved partial pressure of oxygen (12.4 mm Hg; p=0.001) without deleterious effects on cardiac output. Trendelenburg positioning resulted in a small improvement, and methylene blue did not, though individual responses were variable. Future studies should prospectively evaluate these strategies in severe post-transplant hypoxaemia.

High-flow nasal cannula oxygen therapy: Alternative respiratory therapy for severe post-transplant hypoxemia in children with hepatopulmonary syndrome

Severe post-transplant hypoxemia, which is defined as <50 mm Hg of the partial pressure of oxygen in arterial blood/fraction of inspired oxygen (P/F) ratio, is a major post-operative complication with high mortality rates in patients with hepatopulmonary syndrome (HPS). Non-invasive positive pressure ventilation therapy and mechanical ventilation are options for respiratory support of patients with severe post-transplant hypoxemia. However, these therapies are associated with several problems, such as compliance, ventilator-associated pneumonia, and lung injury. We here firstly described two children with HPS who developed severe post-transplant hypoxemia (lowest post-operative P/F ratio, 49.7 and 34.0 mm Hg, respectively) that was successfully managed with high-flow nasal cannula (HFNC) oxygen therapy and vasodilation drugs without adverse complications or necessity of reintubation. We consider that HFNC oxygen therapy could become a safe alternative respiratory therapy or be added to the other such as inhaled nitric oxide (iNO), methylene blue (MB), inhaled epoprostenol, embolization of abnormal pulmonary vessels, and combination of iNO and MB for severe post-transplant hypoxemia in children with HPS.

Hepatopulmonary Syndrome and Portopulmonary Hypertension: Current Status and Implications for Liver Transplantation

PURPOSE OF REVIEW

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH) are both pulmonary vascular complications of advanced liver disease; however, these syndromes have distinct pathophysiology, clinical implications, and management.

RECENT FINDINGS

While both conditions are associated with portal hypertension, HPS results from diffuse pulmonary capillary vasodilation and PoPH results from vasoconstriction and vascular remodeling of pulmonary arteries. In HPS, no medical therapies clearly improve outcomes; however, patients have excellent post-LT outcomes with near uniform reversal of hypoxemia. In PoPH, several medical therapies used in idiopathic pulmonary hypertension have been shown improve pulmonary hemodynamics, symptoms, and potentially LT outcomes; however, further study is needed to determine best treatment regimens, long-term outcomes on medical therapy, and role of LT.

SUMMARY

While HPS results in severe hypoxemia that is usually reversible by LT, PoPH patients develop progressive pulmonary hypertension that may improve with medical therapy.

Preoperative Evaluation and Anesthetic Management of Patients With Liver Cirrhosis Undergoing Cardiac Surgery

Preoperative evaluation and anesthetic management of patients with liver cirrhosis undergoing cardiac surgery remain a clinical challenge because of its high risk for perioperative complications. This narrative review article summarizes the pathophysiology and anesthetic implication of liver cirrhosis on each organ system. It will help physicians to evaluate surgical candidates, to optimize intraoperative management, and to anticipate complications in liver cirrhosis patients undergoing cardiac surgery. Morbidity typically results from bleeding, sepsis, multisystem organ failure, or hepatic insufficiency. These complications occur as a result of the presence of coagulopathy, poor nutritional status, immune dysfunction, cirrhotic cardiomyopathy, and renal and pulmonary dysfunction that occur with liver cirrhosis. Therefore, liver cirrhosis should not be seen as a single disease, but one that manifests with multiorgan dysfunction. Cardiac surgery in patients with liver cirrhosis increases the risk of perioperative complications, and it presents a particular challenge to the anesthesiologist in that nearly every aspect of normally functioning physiology may be jeopardized in a unique way. Accurately classifying the extent of liver disease, preoperative optimization, and surgical risk communication with the patient are crucial. In addition, all teams involved in the surgery should communicate openly and coordinate in order to ensure optimal care. To reduce perioperative complications, consider using off-pump cardiopulmonary bypass techniques and optimal perfusion modalities to mimic current physiologic conditions.

Utilization of Veno-Arterial Extracorporeal Life Support for Acute Respiratory Distress Syndrome After Liver Transplant

In this report, we present a case of successful long-term salvage of a patient with transfusion-related acute lung injury associated with acute respiratory distress syndrome immediately after a liver transplant. The patient was a 29-year-old man with end-stage liver disease due to sclerosing cholangitis who underwent liver transplant. After organ reperfusion, there was evidence of liver congestion, acidosis, coagulopathy, and acute kidney injury. He received 61 units of blood products. Continuous renal replacement therapy was initiated intraoperatively. On arrival to the intensive care unit, the patient was on high-dose pressors, and the patient developed respiratory failure and was immediately placed on veno-arterial extracorporeal membrane oxygenation via open femoral exposure. The patient presented with severe coagulopathy and early allograft dysfunction; therefore, no systemic heparin was administered and no thrombotic events occurred. He required extracorporeal membrane oxygenation support until posttransplant day 4, when resolution of the respiratory and cardiac dysfunction was noted. At 2 years after liver transplant, the patient has normal liver function, normal cognitive function, and stage V chronic kidney disease. We conclude that extracorporeal membrane oxygenation is a valuable therapeutic approach in patients with cardiorespiratory failure after liver transplant.

Approach to the liver transplant early postoperative period: an institutional standpoint

The liver transplant program in our center started in 1992, and post-liver transplant patients are still admitted to the intensive care unit. For the intensive care physician, a learning curve started then, skills were acquired, and a specific practice was established. Throughout this time, several concepts changed, improving the care of these patients. The practical approach varies between liver transplant centers, according to local specificities. Hence, we wanted to present our routine practice to stimulate the debate between dedicated teams, which can allow the introduction of new ideas and potentially improve each local standard of care.

Diosmin enhances the anti-angiogenic activity of sildenafil and pentoxifylline against hepatopulmonary syndrome via regulation of TNF-α/VEGF, IGF-1/PI3K/AKT, and FGF-1/ANG-2 signaling pathways

Hepatopulmonary syndrome (HPS) is a severe complication of hepatic cirrhosis, which is characterized by hypoxia, intrapulmonary vasodilation, inflammation, and angiogenesis. In this study, we aimed to investigate the regulatory effects of diosmin (DS) on selected phosphodiesterase inhibitors against chronic bile duct ligation (CBDL)-induced HPS. Experimentally, Wistar Albino rats were used and HPS was induced by CBDL for 28 days. DS (100 mg/kg, daily, P.O.), sildenafil (Sild; 10 mg/kg, twice daily, P.O.), and pentoxifylline (PTX; 50 mg/kg, daily, P.O.) were evaluated either alone or in combinations for their anti-angiogenic activity. CBDL significantly altered oxidative stress biomarkers and up-regulated pulmonary mRNA expressions of VEGF, IGF-1, ET-1, iNOS, eNOS, and ANG-2 as well as the protein expressions of vWF, FGF-1, PI3K, AKT, p-AKT, TGF-β, HYP, MPO activity and circulating TNF-α. Treatment with DS, Sild, PTX, and their combinations significantly attenuated molecular and cellular changes due to CBDL. Improvement of histopathological changes was also observed after drug treatment which further supported our results. Furthermore, DS combination with Sild or PTX exhibited an improvement in HPS in comparison to each drug alone. Collectively, DS can augment the anti-angiogenic activity of Sild and PTX during HPS through regulation of TNF-α/VEGF, IGF-1/PI3K/AKT, and FGF-1/ANG-2 signaling pathways.

Outcomes of 50 Cases of Pediatric Liver Transplantation for Intrapulmonary Shunt While Considering the Deteriorated Prognosis of Severe Intrapulmonary Shunt Patients

BACKGROUND

Intrapulmonary shunt (IPS) is recognized in 10% of chronic liver disease patients. Liver transplantation (LT) is associated with a high risk of morbidity and mortality in patients with IPS.

PATIENTS AND METHODS

Of 519 pediatric LT cases between November 2005 and October 2018, 50 patients with IPS were enrolled in this study. The patients were divided into 3 groups, according to the shunt ratio, calculated by scintigraphy: mild (15%-20%, n = 26), moderate (20%-40%, n = 19), and severe (> 40%, n = 5). We compared the patients' characteristics before LT and the outcomes of LT between these groups.

RESULTS

The major original disease resulting in LT in the mild and moderate groups was biliary atresia (73.1% and 52.6%, respectively), while that in the severe group was congenital portosystemic shunt (60%). The median ages at LT were 7.5, 6.1, and 8.3 years in the mild, moderate, and severe groups, respectively. All of the mild and moderate IPS patients lived; however, 3 patients with severe IPS (60.0%) died within 3 months. The shunt ratios of the mild and moderate IPS patients normalized within 2 years after LT, while the 2 surviving severe IPS patients showed a slight improvement. The autopsy findings of the lung in 1 deceased severe IPS patient showed medial hypertrophy and proliferation of intimal cells of the pulmonary arteries, suggesting a diagnosis of portopulmonary hypertension.

CONCLUSIONS

LT can be safely performed for mild and moderate IPS patients; however, LT for severe IPS patients should be carefully indicated because concomitant portopulmonary hypertension may be masked by IPS.

Potential Clinical Targets in Hepatopulmonary Syndrome: Lessons From Experimental Models

Hepatopulmonary syndrome (HPS) is a relatively common and potentially severe pulmonary complication of cirrhosis with increased risk of mortality. In experimental models, a complex interaction between pulmonary endothelial cells, monocytes, and the respiratory epithelium, which produces chemokines, cytokines, and angiogenic growth factors, causes alterations in the alveolar microvasculature, resulting in impaired oxygenation. Model systems are critical for evaluating mechanisms and for preclinical testing in HPS, due to the challenges of evaluating the lung in the setting of advanced liver disease in humans. This review provides an overview of current knowledge and recent findings in the rodent common bile duct ligation model of HPS, which recapitulates many features of human disease. We focus on the concepts of endothelial derangement, monocyte infiltration, angiogenesis, and alveolar type II cell dysfunction as main contributors and potential targets for therapy.

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.

Extracorporeal membrane oxygenation for post-transplant hypoxaemia following very severe hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) associated with end-stage liver disease has a high morbidity when room air PaO₂ is less than 50 mm Hg. Safe levels of oxygenation to facilitate transplantation have not been defined despite advancement in care. Postoperatively, hypoxaemia worsens due to ventilation perfusion mismatch contributed by postoperative pulmonary vasoconstriction and due to decrease in endogenous nitric oxide. A 16-year-old boy with cirrhosis presented with HPS and a PaO₂ of 37 mm Hg on room air and underwent living donor liver transplant. Although stable intraoperatively, he desaturated on the second postoperative day. Despite a number of interventions, oxygenation remained critically low on 100% inspired oxygen. Extracorporeal membrane oxygenator (ECMO) was established with instant improvement in oxygenation (PaO₂68 mm Hg), and the patient was eventually salvaged. We suggest that ECMO could be a means of managing refractory post-transplant hypoxaemia in patients with HPS.

Hepatopulmonary Syndrome and Portopulmonary Hypertension: Implications for Liver Transplantation

Hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PoPH) represent serious pulmonary complications of advanced liver diseases. Orthotopic liver transplantation (OLT) is capable of completely resolving the underlying abnormalities associated with HPS. On the other hand, post-OLT response in patients with PoPH is less predictable, although heavily influenced by pre-OLT mean pulmonary arterial pressure. It remains the case that the opportunity to reverse 2 potentially fatal organ dysfunctions in the liver and the lung make HPS and PoPH more than worthy for further clinical investigations.

International Liver Transplant Society Practice Guidelines: Diagnosis and Management of Hepatopulmonary Syndrome and Portopulmonary Hypertension

Two distinct pulmonary vascular disorders, hepatopulmonary syndrome (HPS) and portopulmonary hypertension (POPH) may occur as a consequence of hepatic parenchymal or vascular abnormalities. HPS and POPH have major clinical implications for liver transplantation. A European Respiratory Society Task Force on Pulmonary-Hepatic Disorders convened in 2002 to standardize the diagnosis and guide management of these disorders. These International Liver Transplant Society diagnostic and management guidelines are based on that task force consensus and should continue to evolve as clinical experience dictates. Based on a review of over 1000 published HPS and POPH articles identified via a MEDLINE search (1985-2015), clinical guidelines were based on, selected single care reports, small series, registries, databases, and expert opinion. The paucity of randomized, controlled trials in either of these disorders was noted. Guidelines are presented in 5 parts; I. Definitions/Diagnostic criteria; II. Hepatopulmonary syndrome; III. Portopulmonary hypertension; IV. Implications for liver transplantation; and V. Suggestions for future clinical research.

Change of hepatic arterial systolic/diastolic ratio predicts ischemic type biliary lesion after orthotropic liver transplantation

BACKGROUND

We conducted this prospective nested case-control study for the hepatic artery and portal vein hemodynamic changes after orthotopic liver transplantation.

METHODS

A total 128 cases of orthotropic liver transplantation were analyzed, including 25 cases of ischemic type biliary lesions (ITBL). The portal vein and hepatic artery flow velocities were detected by ultrasound on days 28, 42, and 84 after liver transplantation. In the GLM analysis of Lg(S/D), the P values of Group Effect, Time Effect, and Time×Group were 0.014, 0.376, and 0.008, respectively.

CONCLUSION

Our results show a relatively reduced hepatic artery S/D in ITBL, especially in extrahepatic ITBL.