Prognostic significance of the hepatopulmonary syndrome in patients with cirrhosis

Retropharyngeal Hematoma Following Anterior Cervical Discectomy and Fusion: Identifying Risk to Prevent a Life-Threatening Complication

Study DesignRetrospective cohort.ObjectivesTo assess the incidence, time to presentation, and independent risk factors for retropharyngeal hematoma causing airway obstruction following anterior cervical discectomy and fusion (ACDF).MethodsThe PearlDiver national database was queried for patients who underwent one- to four-level ACDF. Patients who underwent concomitant posterior fusion or had surgical indications related to malignancy, trauma, or infection were excluded. Patients were stratified based on the development of a retropharyngeal hematoma causing airway obstruction within 7 days. Descriptive statistics assessed differences in patient demographics and comorbidities. Univariable and multivariable regression analyses identified independent predictors.ResultsAmong 430,542 patients, 140 (0.03%) developed postoperative retropharyngeal hematoma leading to acute airway obstruction. A significant proportion of patients presented within 1 day of surgery (45 patients, 32.14%), with 23 (16.43%) on day zero and 22 (15.71%) on day 1. Notably, 40.71% of cases occurred after discharge. Independent predictors included ossified posterior longitudinal ligament (OPLL) (aOR: 8.07, P < 0.001), male gender (aOR: 2.30, P < 0.001), hypertension (aOR: 1.67, P < 0.05), viral hepatitis (aOR: 1.57, P < 0.05), and comorbidity index (aOR: 1.14, P < 0.001).ConclusionThis study identified a 0.03% incidence of retropharyngeal hematoma leading to acute airway obstruction and several independent predictors, including comorbidity index, male gender, hypertension, viral hepatitis, and OPLL. Surgeons should consider overnight admission for observation in patients with these risk factors, as a significant proportion of hematomas present within 1 day of surgery.

Predictive models and clinical manifestations of intrapulmonary vascular dilatation and hepatopulmonary syndrome in patients with cirrhosis: Prospective comparative study

BACKGROUND

Patients with cirrhosis with hepatopulmonary syndrome (HPS) have a poorer prognosis. The disease has a subtle onset, symptoms are easily masked, clinical attention is insufficient, and misdiagnosis rates are high.

AIM

To compare the clinical characteristics of patients with cirrhosis, cirrhosis combined with intrapulmonary vascular dilatation (IPVD), and HPS, and to establish predictive models for IPVD and HPS.

METHODS

Patients with cirrhosis were prospectively screened at a liver-specialized university teaching hospital. Clinical information and blood samples were collected, and biomarker levels in blood samples were measured. Patients with cirrhosis were divided into three groups: Those with pure cirrhosis, those with combined IPVD, and those with HPS based on contrast-enhanced transthoracic echocardiography results and the pulmonary alveolar-arterial oxygen gradient values. Univariate logistic regression and Least Absolute Shrinkage and Selection Operator (LASSO) regression methods were utilized to identify risk factors for IPVD and HPS, and nomograms were constructed to predict IPVD and HPS.

RESULTS

A total of 320 patients were analyzed, with 101 diagnosed with IPVD, of whom 54 were diagnosed with HPS. There were statistically significant differences in clinical parameters among these three groups of patients. Among the tested biomarkers, sphingosine 1 phosphate, angiopoietin-2, and platelet-derived growth factor BB were significantly associated with IPVD and HPS in patients with cirrhosis. Following LASSO logistic regression screening, prediction models for IPVD and HPS were established. The area under the receiver operating characteristic curve for IPVD prediction was 0.792 (95% confidence interval [CI]: 0.737-0.847), and for HPS prediction was 0.891 (95%CI: 0.848-0.934).

CONCLUSION

This study systematically compared the clinical characteristics of patients with cirrhosis, IPVD, and HPS, and constructed predictive models for IPVD and HPS based on clinical parameters and laboratory indicators. These models showed good predictive value for IPVD and HPS in patients with cirrhosis. They can assist clinicians in the early prognosis assessment of patients with cirrhosis, ultimately benefiting the patients.

Placental growth factor modulates endothelial NO production and exacerbates experimental hepatopulmonary syndrome

Background & Aims

Hepatopulmonary syndrome (HPS) results from portal hypertension, with or without cirrhosis, and is marked by pulmonary vascular dilations leading to severe hypoxemia. Although placental growth factor (PlGF) is important for vascular growth and endothelial function, its role in HPS is unclear. This study investigated the involvement of PlGF in experimental models of HPS and in patients.

Methods

Circulating PlGF levels were measured in 64 controls and 137 patients with liver disease, with or without HPS. Two rat models, common bile duct ligation (CBDL) and long-term partial portal vein ligation (PPVL), were used. Plgf-knockout (Plgf -/-) rats were generated using CRISPR-Cas9. Lung RNA-sequencing analysis was performed in the CBDL model. The effects of PlGF on endothelial nitric oxide synthase (eNOS) activity in human pulmonary microvascular endothelial cells were also investigated.

Results

Circulating PlGF levels were significantly higher in patients with cirrhosis compared with healthy controls (29.4 ± 1.2 vs. 20.2 ± 0.8 pg/ml, p <0.0001), but no difference were found between patients with and without HPS. PlGF levels were not elevated in patients with extrahepatic portal hypertension. In Plgf -/- rats, there was a protective effect against CBDL-induced HPS, whereas PPVL-induced HPS severity remained unchanged. RNA sequencing coupled with ingenuity pathway analysis identified significant interactions between PlGF and pulmonary eNOS activity. Following CBDL, Plgf -/- rats showed decreased pulmonary eNOS activity and reduced circulating nitric oxide metabolites. In vitro, PlGF stimulation enhanced eNOS activity in human pulmonary microvascular endothelial cells, whereas PlGF knockdown led to a decrease.

Conclusions

These findings indicate that PlGF aggravates cirrhosis-induced HPS through modulation of pulmonary eNOS activity, and is not involved in HPS from extrahepatic portal hypertension.

Impact and implications

This study identified PlGF as a significant contributor to the exacerbation of HPS associated with cirrhosis, through its regulation of pulmonary nitric oxide production. Our findings demonstrated that PlGF deficiency mitigates the severity of both cirrhosis and HPS in the CBDL model, highlighting its potential as a therapeutic target in cirrhosis-induced HPS. Notably, this protective effect was absent in the PPVL model, which induces HPS associated with portal hypertension without cirrhosis. These results open avenues for novel pharmacological interventions aiming to improve outcomes for patients with cirrhosis-induced HPS.

Cerebrovascular Accidents After Orthotopic Liver Transplantation in Patients with Hepatopulmonary Syndrome: A Case Series

Background: Hepatopulmonary syndrome (HPS), defined by the presence of pulmonary vascular dilatations that cause right-to-left transpulmonary shunting of venous blood with a consequential increase in the alveolar-arterial oxygen gradient, is a relatively frequent complication of chronic liver disease. While orthotopic liver transplantation (OLT) is indicated and often curative in HPS patients with end-stage liver disease (ESLD), little is known about the peri- and post-operative-period risks of CVA in OLT recipients with HPS. Case Presentation: We report a case series of five non-consecutive OLT recipients with HPS who developed ischemic and/or hemorrhagic CVAs during or shortly after OLT, raising concern that the risks of neurological complications remain increased even after OLT. Conclusions: Our case series hopes to highlight the importance of close vigilance in this subset of patients, at a time when there may be multiple issues to be addressed in facilitating post-operative recovery.

Disrupted BMP-9 Signaling Impairs Pulmonary Vascular Integrity in Hepatopulmonary Syndrome

Rationale: Hepatopulmonary syndrome (HPS) is a severe complication of liver diseases characterized by abnormal dilation of pulmonary vessels, resulting in impaired oxygenation. Recent research highlights the pivotal role of liver-produced BMP-9 (bone morphogenetic protein-9) in maintaining pulmonary vascular integrity. Objectives: This study aimed to investigate the involvement of BMP-9 in human and experimental HPS. Methods: Circulating BMP-9 levels were measured in 63 healthy control subjects and 203 patients with cirrhosis with or without HPS. Two animal models of portal hypertension were employed: common bile duct ligation with cirrhosis and long-term partial portal vein ligation without cirrhosis. Additionally, the therapeutic effect of low-dose BMP activator FK506 was investigated, and the pulmonary vascular phenotype of BMP-9-knockout rats was analyzed. Measurements and Main Results: Patients with HPS related to compensated cirrhosis exhibited lower levels of circulating BMP-9 compared with patients without HPS. Patients with severe cirrhosis exhibited consistently low levels of BMP-9. HPS characteristics were observed in animal models, including intrapulmonary vascular dilations and an increase in the alveolar-arterial gradient. HPS development in both rat models correlated with reduced intrahepatic BMP-9 expression, decreased circulating BMP-9 level and activity, and impaired pulmonary BMP-9 endothelial pathway. Daily treatment with FK506 for 2 weeks restored the BMP pathway in the lungs, alleviating intrapulmonary vascular dilations and improving gas exchange impairment. Furthermore, BMP-9-knockout rats displayed a pulmonary HPS phenotype, supporting its role in disease progression. Conclusions: The study findings suggest that portal hypertension-induced loss of BMP-9 signaling contributes to HPS development.

Systemic Complications Secondary to Chronic Liver Disease

The systemic sequelae of chronic liver disease (CLD) may be due to portal hypertension and shunting, malnutrition, and/or a low grade inflammatory state. This article will focus on the consequences of chronic liver disease affecting extrahepatic organs. Portal hypertension underlies many systemic complications of CLD. Aside from varices and ascites, portal hypertension may cause both hepatopulmonary syndrome and portopulmonary hypertension leading to respiratory compromise. Cardiomyopathy may also occur secondary to end stage liver disease. Hepatorenal syndrome is also well recognised and hepatic encephalopathy is a consequence of the effect of liver dysfunction on the brain. Compromise of the immune system is well described in end-stage liver disease leading to sepsis and its consequences. Bony disease including osteoporosis and hepatic arthropathy may both be seen in children with CLD. CLD may be asymptomatic initially but then complications may present as the disease progresses. Furthermore, systemic effects of end stage liver disease may complicate liver transplant. These complications often present insidiously or at the time of acute decompensation. Thus, it is important that healthcare providers are vigilant when caring for children with CLD. This article outlines the secondary complications of CLD with an overview of the definition and diagnosis, pathophysiology, management and prognosis of each.

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.

Fraction of exhaled nitric oxide is higher in liver transplant recipients than in controls from the general population: a cohort study

Background

Fraction of exhaled nitric oxide with an expiratory flow of 50 mL/s (FENO50) is a biomarker of eosinophilic airway inflammation. Liver transplant recipients have an increased risk of pulmonary infections, but little is known about the burden of chronic pulmonary diseases in this group. We aimed to assess the prevalence of elevated FENO50 in liver transplant recipients and compare it to controls from the general population.

Methods

FENO50 was measured in 271 liver transplant recipients from The Danish Comorbidity in Liver Transplant Recipients (DACOLT) study and 1,018 age- and sex-matched controls from The Copenhagen General Population Study (CGPS). Elevated FENO50 was defined as ≥25 or ≥50 parts per billion (ppb). The analyses were adjusted for known and suspected confounders.

Results

The median age of the liver transplant recipients was 55 years (interquartile range (IQR) 46-64), and 58% were men. The liver transplant recipients had a higher median FENO50 than the controls [16 ppb (IQR 10-26) vs. 13 ppb (IQR 8-18.), p < 0.001]. Furthermore, the liver transplant recipients had a higher prevalence of elevated FENO50 (for FENO50 ≥25 ppb 27% vs. 11%, p < 0.001 and ≥50 ppb 4% vs. 2%, p = 0.02). The results were similar after adjusting for age, sex, smoking status, use of airway medication, and blood eosinophil counts [the adjusted odds ratio (OR) for FENO50 ≥25 ppb was 3.58 (95% CI: 2.50-5.15, p < 0.0001) and the adjusted OR for FENO50 ≥50 ppb was 3.14 (95% CI: 1.37-7.20, p = 0.007)].

Conclusion

The liver transplant recipients had elevated FENO50, implying increased eosinophilic airway inflammation. The clinical impact of this finding needs further investigation.

Outcomes of liver transplantation for hepatopulmonary syndrome in patients with concomitant respiratory disease

BACKGROUND & AIMS

Concomitant respiratory disease is a common finding in patients with hepatopulmonary syndrome (HPS). Among patients who underwent liver transplantation (LT) for HPS, we compared characteristics and outcome of patients with versus without concomitant respiratory disease.

METHODS

This single center retrospective observational study included patients with HPS who underwent LT between 1999 and 2020.

RESULTS

During the study period, 32 patients with HPS received a LT; nine (28%) with concomitant respiratory disease of whom one required a combined lung-liver transplantation. Patients with concomitant respiratory disease had higher PaCO2 (38 vs. 33 mm Hg, p = .031). The 30-day postoperative mortality was comparable, but the estimated cumulative probability of resolution of oxygen therapy after LT in HPS patients with versus those without concomitant respiratory disease was lower: 63% versus 91% at 12 months and 63% versus 100% at 18 months (HR 95% CI .140-.995, p = .040). In addition to the presence of concomitant respiratory disease (p = .040), history of smoking (p = .012), and high baseline 99mTcMAA shunt fraction (≥20%) (p = .050) were significantly associated with persistent need of oxygen therapy. The 5-year estimated cumulative probability of mortality in patients with concomitant respiratory disease was worse: 50% versus 23% (HR 95% CI .416-6.867, p = .463).

CONCLUSIONS

The presence of a concomitant respiratory disease did not increase the short-term postoperative mortality after LT in patients with HPS. However, it resulted in a longer need for oxygen therapy.

Role of Quantitation of Saline Bubble Studies in Patients with Liver Cirrhosis

OBJECTIVE

Microbubble contrast echocardiography with a late positive signal enables the detection of intrapulmonary vascular dilation, including hepatopulmonary syndrome, in patients with end-stage liver disease. We assessed the relationship between the severity of bubble study and clinical outcome.

METHODS

We retrospectively analyzed 163 consecutive patients with liver cirrhosis who underwent an echocardiogram with bubble study from 2018 to 2021. Patients who were diagnosed with a late positive signal were divided into three groups: grade 1 (1-9 bubbles), grade 2 (10-30 bubbles) and grade 3 (>30 bubbles).

RESULTS

Fifty-six percent of the patients had a late positive bubble study (grade 1: 31%, grade 2: 23%, grade 3: 46%). Patients with grade 3 had a significantly higher international normalized ratio, model for end-stage liver disease score and Child-Pugh score and a lower peripheral oxygen saturation compared with patients with a negative study. In patients undergoing liver transplant (LT), survival rates were similar among the groups (3-mo: >87%, 1-y: >87%, 2-y: >83%). However, survival rate was lower in grade 3 patients without LT (3-mo: 81%, 1-y: 64%, 2-y: 39%).

CONCLUSION

Patients with grade 3 had much worse mortality without LT compared with other groups. However, after LT, all grades had equal survival. Therefore, patients with grade 3 may be considered as higher priority for LT.

Vascular Extracellular Vesicles Indicate Severe Hepatopulmonary Syndrome in Cirrhosis

Background: Hepatopulmonary syndrome (HPS) is a pulmonary vasculature complication in the setting of liver disease that is characterized by pathological vasodilation resulting in arterial oxygenation defects. We investigated the role of extracellular vesicles (EV) in cirrhosis patients with HPS, as well as the functional effect of EV administration in a common bile duct ligation (CBDL) HPS mouse model. Methods: A total of 113 cirrhosis patients were studied: 42 (Gr. A) with HPS and 71 (Gr. B) without HPS, as well as 22 healthy controls. Plasma levels of EV associated with endothelial cells, epithelial cells, and hepatocytes were measured. The cytokine cargoes were estimated using ELISA. The effect of EV administered intranasally in the CBDL mouse model was investigated for its functional effect in vascular remodeling and inflammation. Results: We found endothelial cells (EC) associated EV (EC-EV) were elevated in cirrhosis patients with and without HPS (p < 0.001) than controls. EC-EV levels were higher in HPS patients (p = 0.004) than in those without HPS. The epithelial cell EVs were significantly high in cirrhosis patients than controls (p < 0.001) but no changes found in patients with HPS than without. There was a progressive increase in EC-EV levels from mild to severe intrapulmonary shunting in HPS patients (p = 0.02 mild vs. severe), and we were able to predict severe HPS with an AUROC of 0.85; p < 0.001. An inverse correlation of EC-EVs was found with hemoglobin (r = −0.24; p = 0.031) and PaO2 (r = 0.690; p = 0.01) and a direct correlation with MELD (r = 0.32; p = 0.014). Further, both TNF-α (p = 0.001) and IL-1β (p = 0.021) as cargo levels were significantly elevated inside the EVs of HPS patients than without HPS. Interestingly, upon administration of intranasal EVs, there was a significant decrease in Evans blue accumulation and lung wet–dry ratio (p = 0.042; 0.038). A significant reduction was also noticed in inflammation and cholestasis. Conclusion: High levels of plasma EC-EV levels were found in patients with HPS with elevated pro-inflammatory cytokine cargoes. EC-EVs were indicative of severe HPS condition. In the CBDL HPS model, we were able to prove the beneficial effects of improving vascular tone, inflammation, and liver pathogenesis.

Model for End-Stage Liver Disease/Pediatric End-Stage Liver Disease exception policy and outcomes in pediatric patients with hepatopulmonary syndrome requiring liver transplantation

Hepatopulmonary syndrome (HPS) is associated with increased waitlist mortality in liver transplantation (LT) candidates. Children with HPS are granted Model for End-Stage Liver Disease (MELD)/Pediatric End-Stage Liver Disease (PELD) exception points for waitlist prioritization in the United States based on criterion developed for adults. In this study, the impact of this MELD/PELD exception policy on post-LT survival in children was examined. A retrospective cohort of patients aged younger than 18 years with a MELD/PELD exception request who underwent LT between 2007 and 2018 were identified in the Scientific Registry of Transplant Recipients. Patients were stratified by waitlist partial pressure of arterial oxygen (PaO 2 ) to assess risk factors for waitlist mortality and post-LT survival. Among 3082 pediatric LT recipients included in the study, 124 patients (4%) received MELD/PELD exception points for HPS. Patients with HPS were a median age of 9 years (interquartile range: 6, 12 years), 54.8% were girls, and 54% were White. Most patients (87.9%) were listed with laboratory MELD/PELD scores <15. Waitlist mortality for patients with HPS exception points was rare and not different from patients without HPS. When stratified by pre-LT PaO 2 , hypoxemia severity was not associated with differences in 1-, 3-, or 5-year survival rates after LT ( p = 0.13). However, patients with HPS showed a slightly lower survival rate at 5 years compared with patients without HPS (88.7% vs. 93.4%; p = 0.04). MELD/PELD exceptions for children with HPS mitigated waitlist mortality, and recipients with HPS experienced excellent 5-year survival after LT, although slightly lower than in patients without HPS. Unlike adults with HPS, the severity of pre-LT hypoxemia in children does not impact post-LT survival. These data suggest that adult criteria for granting MELD/PELD exception points may not appropriately capture HPS severity in pediatric patients. Further prospective multicenter studies to examine the risk factors predicting negative survival outcomes in children with HPS are warranted.

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.

Impact of hepatopulmonary syndrome in liver transplantation candidates and the role of angiogenesis

BACKGROUND

Hepatopulmonary syndrome affects 10-30% of patients with cirrhosis and portal hypertension. We evaluated the serum angiogenic profile of hepatopulmonary syndrome and assessed the clinical impact of hepatopulmonary syndrome in patients evaluated for liver transplantation.

METHODS

The Pulmonary Vascular Complications of Liver Disease 2 study was a multicentre, prospective cohort study of adults undergoing their first liver transplantation evaluation. Hepatopulmonary syndrome was defined as an alveolar-arterial oxygen gradient ≥15 mmHg (≥20 mmHg if age >64 years), positive contrast-enhanced transthoracic echocardiography and absence of lung disease.

RESULTS

We included 85 patients with hepatopulmonary syndrome and 146 patients without hepatopulmonary syndrome. Patients with hepatopulmonary syndrome had more complications of portal hypertension and slightly higher Model for End-Stage Liver Disease-Na score compared to those without hepatopulmonary syndrome (median (interquartile range) 15 (12-19) versus 14 (10-17), p=0.006). Hepatopulmonary syndrome patients had significantly lower 6-min walk distance and worse functional class. Hepatopulmonary syndrome patients had higher circulating angiopoietin 2, Tie2, tenascin C, tyrosine protein kinase Kit (c-Kit), vascular cell adhesion molecule 1 and von Willebrand factor levels, and lower E-selectin levels. Patients with hepatopulmonary syndrome had an increased risk of death (hazard ratio 1.80, 95% CI 1.03-3.16, p=0.04), which persisted despite adjustment for covariates (hazard ratio 1.79, 95% CI 1.02-3.15, p=0.04). This association did not vary based on levels of oxygenation, reflecting the severity of hepatopulmonary syndrome.

CONCLUSION

Hepatopulmonary syndrome was associated with a profile of abnormal systemic angiogenesis, worse exercise and functional capacity, and an overall increased risk of death.

Hepatopulmonary syndrome

Hepatopulmonary syndrome (HPS) is a pulmonary vascular complication of liver disease, which adversely affects prognosis. The disease is characterised by intrapulmonary vascular dilatations and shunts, resulting in impaired gas exchange. A complex interaction between the liver, the gut and the lungs, predominately impacting pulmonary endothelial cells, immune cells and respiratory epithelial cells, is responsible for the development of typical pulmonary alterations seen in HPS. Liver transplantation is the only therapeutic option and generally reverses HPS. Since the implementation of the model for end-stage liver disease (MELD) standard exception policy, outcomes in patients with HPS have been significantly better than they were in the pre-MELD era. This review summarises current knowledge and highlights what’s new regarding the diagnosis and management of HPS, and our understanding of pathogenesis based on experimental models and translational studies.

The Impact of Cirrhosis on Outcomes of Patients Admitted With Diabetic Ketoacidosis: A Nationwide Study

Introduction Diabetic ketoacidosis (DKA) is the most common acute hyperglycemic emergency in people with diabetes mellitus (DM). Cirrhosis is a consequence of chronic inflammation that is followed by hepatic fibrosis. It has been noted that cirrhosis is associated with an increased risk of developing type II DM due to altered glucose homeostasis. The prognostic value of DM in cirrhotic patients has been studied before and was found to be associated with lower survival. However, the risk of mortality and adverse events in cirrhotic patients admitted with DKA needs further evaluation. The aim of this study is to compare outcomes in patients with cirrhosis admitted to the hospital with DKA compared to non-cirrhotic patients. Methods The data for this study were extracted from the National Inpatient Sample (NIS) 2016-2019. The NIS was queried for all patients who had a discharge diagnosis of DKA. Patients with cirrhosis were identified and subclassified into compensated and decompensated cirrhosis using the International Classification of Diseases 10th revision, Clinical Modification (ICD-10-CM) codes. Patients without cirrhosis were the control group. ICD-10-CM codes that have been validated for cirrhosis were utilized. The primary outcome was in-hospital mortality. Secondary outcomes were hospital charges, length of stay (LOS), and in-hospital complications, including shock, mechanical ventilation, and acute kidney injury (AKI) requiring dialysis. Results We included 1,098,875 hospitalizations with a discharge diagnosis of DKA. Overall, 9,190 patients had compensated cirrhosis and 4,355 had decompensated cirrhosis. Cirrhotic patients had overall worse outcomes compared to non-cirrhotics. Decompensated cirrhotics had the highest mortality (11.26%; 95% confidence interval [CI]: 9.36% to 13.49%) compared to compensated cirrhotics (3.54%; 95% CI: 2.79% to 4.48%) and non-cirrhotics (2.15%; 95% CI: 1.89% to 2.43%). Similarly, decompensated cirrhotics also had the highest LOS, total charges, and in-hospital complications among the groups. On multivariate analysis, decompensated cirrhosis, rather than compensated cirrhosis, was an independent predictor of higher mortality (adjusted odds ratio [AOR]: 2.30; 95% CI: 1.81 to 2.92), LOS (regression coefficient: +1.82 days; 95% CI: +1.19 to +2.44 days), hospital charges (regression coefficient: +$28,497; 95% CI: +$18,107 to +$38,887), shock (AOR: 2.31; 95% CI: 1.68 to 3.18), mechanical ventilation (AOR: 1.91; 95% CI: 1.58 to 2.29), and AKI requiring dialysis (AOR: 2.31; 95% CI: 1.68 to 3.18). Conclusion This study showed that patients with decompensated liver cirrhosis who were admitted with DKA had the worst in-hospital outcomes. Additionally, only decompensated cirrhosis was an independent predictor of worse outcomes. Decompensated cirrhotics who develop DKA should be approached with more caution with a probable lower threshold for intensive care unit admission for a higher level management.

Diagnosis of Hepatopulmonary Syndrome in a Large Integrated Health System

BACKGROUND & AIMS

Data on the accuracy of the diagnosis of hepatopulmonary syndrome (HPS) in cirrhosis is limited. We evaluated the clinical characteristics of patients with International Classification of Diseases (ICD) codes for hepatopulmonary syndrome (HPS) in a large integrated health system.

METHODS

A retrospective review of encounters was performed of all patients with ICD-9-CM and/or ICD-10-CM diagnosis of cirrhosis and HPS from 2014-2019 in a multi-state health system. Demographics and cardiopulmonary testing closest to the time of HPS diagnosis were recorded. HPS was defined using standard criteria.

RESULTS

A total of 42,749 unique individuals with cirrhosis were identified. An ICD diagnosis of HPS was found in 194 patients (0.45%), of which 182 had clinically confirmed cirrhosis. 143 (78.5%) underwent contrast-enhanced transthoracic echocardiography, and 98 (54%) had delayed shunting. Among them, 61 patients had a documented arterial blood gas, with 53 showing abnormal oxygenation (A-a gradient of >15 mm Hg). 12 were excluded due to significant pulmonary function test abnormalities and abnormal oxygenation from other cardiopulmonary diseases. Ultimately, 41 (22.5%) fulfilled the criteria for HPS. When stratifying those with an ICD code diagnosis of HPS into HPS, no HPS and indeterminate HPS groups, based on standard diagnostic criteria for HPS, we found that the confirmed HPS patients had similar complications except for less portopulmonary hypertension, worse gas exchange, less cardiopulmonary disease and were more often diagnosed in transplant centers.

CONCLUSIONS

The diagnosis of HPS by ICD code is made in an extremely small subset of a sizeable cirrhotic cohort. When made, only a minority of these patients meet diagnostic criteria. Our findings highlight the need for improved education and more effective screening algorithms.

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.

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.

Hepatopulmonary Syndrome: A Nationwide Analysis of Epidemiological Trends and Outcomes From 2012 to 2018

Background

This study was designed to determine the epidemiological trends and adverse outcomes of hepatopulmonary syndrome (HPS).

Methods

This retrospective interrupted trend study analyzed data from the Nationwide Inpatient Sample (NIS) for the years 2012, 2014, 2016 and 2018 to identify adult (≥ 18 years) hospitalizations with a diagnosis of HPS. We highlighted epidemiological trends for HPS. Inpatient mortality, mean length of stay (LOS) and mean total hospital charge (THC) were estimated using multivariate regression trend analysis.

Results

We observed an increase in the total number of HPS hospitalizations from 1,565 in 2012 to 2,495 in 2018, with mean age ranging from 55.8 to 58.1 years. There was a trend towards increasing hospitalizations (P-trend < 0.001) with increasing mean age (P-trend = 0.003) for HPS. Whites made up most of the study population. The inpatient mortality for HPS ranged from 12.4% to 12.6%, but there was no statistically significant trend for mortality (P-trend = 0.534) between 2012 and 2018. Additionally, there was no change in both mean LOS (P-trend = 0.545) and mean THC (P-trend = 0.534) for HPS for these years.

Conclusions

Hospitalizations and mean age for HPS were on the rise. Inpatient mortality ranged from 12.4% to 12.6%; however, a statistically significant trend for mortality was absent.

Outcomes of liver transplantation in patients with hepatopulmonary syndrome in the pre and post-MELD eras: A systematic review

BACKGROUND

The lack of large hepatopulmonary syndrome cohorts undergoing liver transplantation (LT) has resulted in limited information about post-LT outcomes and expectations.

METHODS

The long and short-term outcomes of LT in patients with hepatopulmonary syndrome (HPS) were evaluated before and after the implementation of Model for Endstage Liver Disease (MELD) score in 2002, granting exception points for patients with HPS. PubMed/Medline, Embase, Web of Science and Scopus databases were searched for published and unpublished studies from 01/1990 to 04/2019. Studies that included HPS patients who underwent LT and reported post-LT outcomes and HPS severity were reviewed. After reviewing the full text of 1421 articles, 30 were included in the pre-MELD era (before 2002) and 60 in the post-MELD era.

RESULTS

A total of 598 patients (210 children and 388 adults) with HPS who underwent LT were included in this systematic review. In children, 5-year survival probability was similar in the pre and post-MELD groups (85.7% vs. 97.4; p = 0.09). Median post-transplant PaO2 in room air was higher in the post-MELD group (71 [53-87] vs. 97 [80-108] mmHg: p = 0.008). In adults, 5-year survival probability was higher in the post-MELD era (73 vs. 87.3%; p = 0.008). Median post-transplant PaO2 in room air was higher in post-MELD group (75 [63-85] vs. 87 [75-95] mmHg; p = 0.001)..

CONCLUSIONS

After MELD exception implementation, survival rates and post-transplant oxygenation improved in adult patients with HPS who underwent liver transplantation, whereas only post-transplant oxygenation improved in children.

Hepatopulmonary syndrome is related to the development of acute-on-chronic liver failure and poor prognosis in cirrhotic patients

BACKGROUND AND AIMS

Long-term prospective data on hepatopulmonary syndrome (HPS) from a large number of patients, especially in Asian patients, are lacking. We evaluated the long-term prognosis of HPS and the development of acute-on-chronic liver failure (ACLF), and related factors.

METHODS

A total of 142 patients with cirrhosis who underwent saline-agitated contrast echocardiography for the diagnosis of HPS were enrolled and observed prospectively from 2014 to 2019.

RESULTS

A total of 59 patients (41%) were diagnosed with HPS (24 grade 1, 23 grade 2, 12 grade 3). Thirty-eight and 37 patients died in the HPS and non-HPS groups, respectively (p < 0.01). The 5-year survival rate was 47% in the HPS group and 62% in the non-HPS group. In the Cox proportional hazards model, HPS and Model for End-stage Liver Disease (MELD) score ≥ 18, and Child-Turcotte-Pugh (CTP) class B/C were significant risk factors for mortality after adjusting for other risk factors (HPS hazard ratio [HR] = 1.9, p = 0.01; MELD score ≥ 18 HR = 2.3, p < 0.01; CTP class B/C HR = 2.9, p < 0.01). Compared to that in non-HPS group, the HPS group had a significantly higher incidence of ACLF during follow-up (p < 0.01) and more frequently presented with lung involvement of ACLF (p = 0.03).

CONCLUSIONS

In the long-term follow-up cohort, patients with HPS showed poorer prognosis than that of patients without HPS. HPS was a risk factor for ACLF development independent of hepatic dysfunction, and lung involvement was significantly common than without ACLF.

New clinical and pathophysiological perspectives defining the trajectory of cirrhosis

Traditionally, the complications of cirrhosis, namely variceal bleeding, ascites and hepatic encephalopathy, were thought to result predominantly from circulatory dysfunction and altered organ perfusion arising as a result of portal hypertension. Over the past 20 years, large, international prospective studies have indicated the importance of systemic inflammation and organ immunopathology as additional determinants of organ dysfunction in cirrhosis, which not only manifests in the liver, brain, circulation and the kidneys, but also the immune system, gut, muscles, adrenal glands, reproductive organs, heart and lungs. This review provides an overview of the traditional and emerging concepts around the initiation and maintenance of organ dysfunction in cirrhosis and proposes a new paradigm based upon a better understanding of acute decompensation of cirrhosis. The interaction between the traditional concepts and the emerging perspectives remains a matter of great interest and the basis for future research.

Hospice care for end stage liver disease in the United States

INTRODUCTION

Patients with end-stage liver disease (ESLD) have impaired physical, psychological, and social functions, which can diminish patient quality of life, burden family caregivers, and increase health-care utilization. For those with a life expectancy of less than six months, these impairments and their downstream effects can be addressed effectively through high-quality hospice care, delivered by multidisciplinary teams and focused on the physical, emotional, social, and spiritual wellbeing of patients and caregivers, with a goal of improving quality of life.

AREAS COVERED

In this review, we examine the evidence supporting hospice for ESLD, we compare this evidence to that supporting hospice more broadly, and we identify potential criteria that may be useful in determining hospice appropriateness.

EXPERT OPINION

Despite the potential for hospice to improve care for those at the end of life, it is underutilized for patients with ESLD. Increasing the appropriate utilization of hospice for ESLD requires a better understanding of patient eligibility, which can be based on predictors of high short-term mortality and liver transplant ineligibility. Such hospice criteria should be data-driven and should accommodate the uncertainty faced by patients and physicians.

Clinical outcomes and risk factors of hepatopulmonary syndrome in children

Hepatopulmonary syndrome (HPS) is defined as three distinct features: liver disease, hypoxemia, and intrapulmonary vasodilation. The purpose of this study was to investigate the clinical outcomes of pediatric HPS and to identify the risk factors for HPS in children with biliary atresia (BA). We performed a retrospective cohort study of all children who were diagnosed with HPS between 2000 and 2018 at Seoul National University Hospital. The clinical features and outcomes of the 10 patients diagnosed with HPS were reviewed. To clarify the risk factors of HPS in patients with BA, we reviewed 120 patients diagnosed with BA. Underlying liver disease was BA in 8 patients, portal vein agenesis in 1 patient, and portal vein thrombosis in 1 patient. A total of 7 patients underwent liver transplantation (LT). Currently, all seven patients, including 3 patients with severe HPS, survived after LT. The prevalence of HPS in children with BA was 7%. Polysplenia/interrupted inferior vena was the only risk factor for HPS in BA patients in multivariate analysis. The Pediatric End-Stage Liver Disease score was not associated with the development of HPS. Children with severe HPS undergoing LT had excellent outcomes. Screening for HPS in children with BA is required regardless of the severity of liver diseases.

Keeping Patients with End-Stage Liver Disease Alive While Awaiting Transplant: Management of Complications of Portal Hypertension

Complications of portal hypertension such as gastroesophageal variceal hemorrhage, ascites, and spontaneous bacterial peritonitis, as well as pulmonary complications, are often responsible for diminished quality of life, excess morbidity and mortality, increased health care resource use and expenditure, and dropout from the liver transplant (LT) waiting list. Therefore, the care of LT candidates on the waiting list must be centered on anticipation and prompt intervention for these complications.

Pulmonary Complications in Candidates for Liver Transplantation

The liver plays a pivotal role in maintaining the homeostasis of various organ systems. Also, end-stage liver disease and its complications are major causes of morbidity and mortality among adults. Individuals who develop a chronic liver disease are at increased risk of progression to multi-organ dysfunction, including the pulmonary system. The clinical complications of pulmonary problems related to the presence of liver disease range from mild (such as hypoxemia) to life-threatening diseases (such as portopulmonary hypertension and hepatopulmonary syndrome). Herein, the major pulmonary complications related to liver cirrhosis and considerations for performing liver transplantation are reviewed.

Pulmonary Complications in Patients with Liver Cirrhosis

Patients with advanced chronic liver diseases, particularly with decompensated liver cirrhosis, can develop specific pulmonary complications independently of any pre-existing lung disease. Especially when dyspnea occurs in combination with liver cirrhosis, patients should be evaluated for hepato-pulmonary syndrome (HPS), porto-pulmonary hypertension (PPHT), hepatic hydrothorax and spontaneous bacterial empyema, which represent the clinically most relevant pulmonary complications of liver cirrhosis. Importantly, the pathophysiology, clinical features, diagnosis and the corresponding therapeutic options differ between these entities, highlighting the role of specific diagnostics in patients with liver cirrhosis who present with dyspnea. Liver transplantation may offer a curative therapy, including selected cases of HPS and PPHT. In this review article, we summarize the pathogenesis, clinical features, diagnostic algorithms and treatment options of the 4 specific pulmonary complications in patients with liver cirrhosis.

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.

Reduced circulating BMP10 and BMP9 and elevated endoglin are associated with disease severity, decompensation and pulmonary vascular syndromes in patients with cirrhosis

Background

BMP9, originating from the liver, and BMP10 are circulating BMPs that preserve vascular endothelial integrity. We assessed BMP9, BMP10 and soluble endoglin (sEng) levels and their relationships to liver disease severity and associated pulmonary vascular syndromes in a cohort of well-characterised liver disease patients.

Methods

Plasma samples from patients with liver disease (n = 83) and non-disease controls (n = 21) were assayed for BMP9, BMP10 and sEng. Levels were also assessed in a separate cohort of controls (n = 27) and PoPH patients (n = 8). Expression of mRNA and immunohistochemical staining was undertaken in liver biopsy specimens. Plasma BMP activity was assessed using an endothelial cell bioassay.

Findings

Plasma BMP9 and BMP10 levels were normal in patients with compensated cirrhosis or fibrosis without cirrhosis, but markedly reduced in patients with decompensated cirrhosis, including those with hepatopulmonary syndrome (HPS) or portopulmonary hypertension (PoPH). Liver biopsy specimens revealed reduced mRNA expression and immunostaining for these ligands. Patient plasma samples with reduced BMP9 and BMP10 levels exhibited low BMP activity that was restored with exogenous BMP9. Endoglin mRNA expression was increased in cirrhotic livers and elevated circulating sEng levels in PoPH and HPS patients suggested increased endothelial sEng shedding in these syndromes.

Interpretation

Plasma BMP9 and BMP10 levels are reduced in decompensated cirrhosis, leading to reduced circulating BMP activity on the vascular endothelium. The pulmonary complications of cirrhosis, PoPH and HPS, are associated with markedly reduced BMP9 and BMP10 and increased sEng levels, suggesting that supplementation with exogenous ligands might be a therapeutic approach for PoPH and HPS.

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.

A Role for Alveolar Exhaled Nitric Oxide Measurement in the Diagnosis of Hepatopulmonary Syndrome

GOALS

The authors sought to characterize predominantly alveolar exhaled nitric oxide (eNO) in hepatopulmonary syndrome (HPS) compared with non-HPS, changes after liver transplantation, and diagnostic properties.

BACKGROUND

HPS is defined by liver disease, intrapulmonary vascular dilatations (IPVDs), and hypoxemia. Rat models and small human studies suggest that NO overproduction may cause IPVDs.

STUDY

A retrospective review of the Canadian HPS Database (2007 to 2017) and prospective eNO measurement (main outcome) in healthy controls (measurement expiratory flow, 200 mL/s). HPS was defined as: (1) liver disease; (2) contrast echocardiography consistent with IPVDs; and (3) partial pressure of arterial oxygen <70 mm Hg with alveolar-arterial gradient >20 mm Hg; subclinical HPS as criteria (1) and (2) only; and no HPS as criterion (1) only. Current smokers and subjects with asthma or pulmonary hypertension were excluded. A linear mixed effects model was used to compare eNO between groups and before and after transplantation.

RESULTS

eNO was 10.4±0.7 ppb in HPS (n=26); 8.3±0.6 ppb in subclinical HPS (n=38); 7.1±1.0 ppb in no HPS (n=15); and 5.6±0.7 ppb in controls (n=30) (P<0.001). eNO decreased from 10.9±0.8 ppb preliver to 6.3±0.8 ppb postliver transplant (n=6 HPS, 6 subclinical HPS) (P<0.001). eNO <6 ppb was 84.4% (73.1% to 92.2%) sensitive and ≥12 ppb was 78.1% (69.4% to 85.3%) specific for HPS (vs. subclinical HPS).

CONCLUSIONS

HPS subjects have higher alveolar eNO than non-HPS subjects, levels normalize with liver transplantation. Applying eNO cutoff values may aid in HPS diagnosis.

Hepatopulmonary syndrome has low prevalence of pulmonary vascular abnormalities on chest computed tomography

Purpose

Hepatopulmonary syndrome (HPS) is defined as an arterial oxygenation defect induced by intrapulmonary vascular dilatations associated with hepatic disease. This study aimed to assess the prevalence of type 1 and 2 pulmonary vascular abnormalities on chest computed tomography (CT) in patients with cirrhosis and HPS and to characterize intra- and interobserver reliability.

Materials and methods

Two thoracic radiologists retrospectively evaluated chest CT scans from 38 cirrhosis patients with HPS. They classified the pulmonary vascular abnormalities as type 1 (multiple dilated distal pulmonary arteries), type 2(nodular dilatation or individual pulmonary arterial malformation), or absence of abnormality. Furthermore, they measured the diameters of the central pulmonary arteries and subsegmental pulmonary arteries and bronchi. We analyzed the prevalence, intraobserver reliability, and interobserver reliability of abnormal CT findings related to HPS, and the correlation of these findings with partial arterial oxygen pressure (PaO₂).

Results

The overall prevalence of pulmonary vascular abnormalities was 28.9% (95% confidence intervals: 15.4%, 45.9%). Moreover, 26.3% of patients had type 1 abnormality (13.4%, 43.1%) and 2.6% of patients had type 2 abnormality (0.0%, 13.8%). The intraobserver reliability kappa value was 0.666 (0.40, 0.91) and the interobserver kappa value was 0.443 (0.12, 0.77). There was no correlation between pulmonary vascular abnormalities on CT and PaO₂ values.

Conclusions

The prevalence of pulmonary vascular abnormalities on chest CT of patients with cirrhosis and HPS is low and not correlated with PaO₂. These findings question the usefulness of chest CT for the evaluation of patients with cirrhosis and HPS.

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.

Liver disease is an independent predictor of poor 30-day outcomes following surgery for degenerative disease of the cervical spine

BACKGROUND AND CONTEXT

The impact of underlying liver disease on surgical outcomes has been recognized in a wide variety of surgical disciplines. However, less empiric data are available about the importance of liver disease in spinal surgery.

PURPOSE

To measure the independent impact of underlying liver disease on 30-day outcomes following surgery for the degenerative cervical spine.

STUDY DESIGN

Retrospective comparative study.

PATIENT SAMPLE

A cohort of 21,207 patients undergoing elective surgery for degenerative disease of the cervical spine from the American College of Surgeons National Surgical Quality Improvement Program.

OUTCOME MEASURES

Outcome measures included mortality, hospital length of stay, and postoperative complications within 30 days of surgery.

METHODS

The NSQIP dataset was queried for patients undergoing surgery for degenerative disease of the cervical spine from 2006 to 2015. Assessment of underlying liver disease was based on aspartate aminotransferase-to-platelet ratio index and Model of End-Stage Liver Disease-Sodium scores, computed from preoperative laboratory data. The effect of liver disease on outcomes was assessed by bivariate and multivariate analyses, in comparison with 16 other preoperative and operative factors.

RESULTS

Liver disease could be assessed in 21,207 patients based on preoperative laboratory values. Mild liver disease was identified in 2.2% of patients, and advanced liver disease was identified in 1.6% of patients. The 30-day mortality rates were 1.7% and 5.1% in mild and advanced liver diseases, respectively, compared with 0.6% in patients with healthy livers. The 30-day complication rates were 11.8% and 31.5% in these patients, respectively, compared with 8.8% in patients with healthy livers. In multivariate analysis, the presence of any liver disease (mild or advanced) was independently associated with an increased risk of mortality (OR=2.00, 95% CI=1.12-3.55, p=.019), morbidity (OR=1.35, 95% CI=1.07-1.70, p=.012), and length of hospital stay longer than 7 days (OR=1.73, 95% CI=1.40-2.13, p<.001), when compared with 18 other preoperative and operative factors. Liver disease was also independently associated with perioperative respiratory failure (OR=1.80, 95% CI=1.21-2.68, p=.004), bleeding requiring transfusion (OR=1.43, 95% CI=1.01-2.02, p=.044), wound disruption (OR=2.82, 95% CI=1.04-7.66, p=.042), and unplanned reoperation (OR=1.49, 95% CI=1.05-2.11, p=.025).

CONCLUSIONS

Liver disease independently predicts poor perioperative outcome following surgery for degenerative disease of the cervical spine. Based on these findings, careful consideration of a patient's underlying liver function before surgery may prove valuable in surgical decision-making, preoperative patient counseling, and postoperative patient care.

Pulse Oximetry Is Insensitive for Detection of Hepatopulmonary Syndrome in Patients Evaluated for Liver Transplantation

Screening for hepatopulmonary syndrome (HPS) using pulse oximetry is recommended in liver transplant (LT) candidates because mortality is increased, independently of the severity of the oxygenation defect. LT exception points may be afforded to those with HPS and severe hypoxemia. We assessed the screening characteristics of pulse oximetry for HPS. The Pulmonary Vascular Complications of Liver Disease 2 study is a multicenter, prospective cohort study of adults undergoing their first LT evaluation. Patients underwent protocolized assessment of oxygen saturation by pulse oximetry (SpO2 ), arterial blood gas, spirometry, and contrast-enhanced echocardiography (CE). HPS was defined as an alveolar-arterial gradient ≥15 mm Hg (≥20 mm Hg if age >64 years), intrapulmonary vascular dilatation on CE, and absence of lung disease. The study sample included 363 patients. Of these, 75 (20.7%; 95% confidence interval [CI], 16.6%-25.2%) met the criteria for HPS. The area under the receiver operating characteristic curve (or c-statistic) for SpO2 in discriminating HPS was 0.59 (95% CI, 0.51-0.66). An SpO2 <96%, recommended by practice guidelines as a threshold to require further testing, had low sensitivity (28%; 95% CI, 18%-28%). The c-statistic of SpO2 in discriminating HPS with a partial pressure of oxygen (PaO2 ) <60 mm Hg (eligible for LT exception points) was 0.76 (95% CI, 0.46-1.00). An SpO2 cutoff of <96% had higher sensitivity for detecting HPS with PaO2 <60 mm Hg (71%; 95% CI, 38%-100%) but was still inadequate. Conclusion: Pulse oximetry is not sufficiently sensitive to screen for HPS in LT candidates. Arterial blood gas and CE are required in LT candidates for diagnosis of HPS.

Screening for Hepatopulmonary Syndrome in Cirrhotic Patients Using Technetium 99m-macroaggregated Albumin Perfusion Lung Scan (Tc-MAA): Diagnostic Approach and Clinical Correlations

BACKGROUND AND AIMS

The aims of this study were to prospectively screen cirrhotic patients with arterial blood gas test and albumin perfusion scan, identify those fulfilling the classic hepatopulmonary syndrome (HPS) criteria, correlate with clinical parameters, and evaluate the survival of patients with HPS compared with those without HPS in a genetically homogenous Cretan cirrhotic population.

MATERIALS AND METHODS

Data on consecutive 102 patients within 1 year were collected and analyzed. All patients underwent a technetium 99m-macroaggregated albumin perfusion lung scan (Tc-MAA). Diagnosis of HPS was based on the presence of the quantitative index Tc-MAA≥6% and a [P(A-a)O2]≥15 mm Hg (≥20 mm Hg for patients over >64 y).

RESULTS

In 94/102 patients, complete scintigraphic data were available. In total, 24 (26%) patients fulfilled the diagnostic criteria of HPS; 95.8% of them had mild-to-moderate HPS. In 8 patients the Tc-MAA scintigraphy could not be interpreted. There was no difference in HPS between decompensated (24.6%) and compensated cirrhosis (27.3%). In the multivariate analysis only the quantitative index was significant for the diagnosis of HPS (P=0.001, odds ratio; 95% confidence interval, 7.05; 2.27-21.87). Kaplan- Meier survival curves indicated a similar overall prognosis for patients diagnosed with HPS (P=0.105).

CONCLUSIONS

HPS is a frequent complication of cirrhosis. Mild-to-moderate HPS has no significant effect on survival of cirrhotic patients. The quantitative Tc-MAA test is a reliable tool for diagnosis.