Portopulmonary hypertension

Hepatopulmonary Syndrome and Liver Transplantation: Impact on Survival and Postoperative Complications

BACKGROUND Liver transplantation (LT) is the preferred treatment for patients with cirrhosis who have hepatopulmonary syndrome (HPS). However, the effect of HPS on LT remains controversial. We assessed the correlation between HPS severity and LT survival and compared the incidence of postoperative complications between patients with and without HPS undergoing LT. MATERIAL AND METHODS We retrospectively reviewed the recipients who received living-donor LT in our institute between January 2016 and July 2019. Patients with HPS (HPS group) and patients without HPS (non-HPS group) were included in our study. HPS is defined as a defect in arterial oxygenation caused by the presence of intrapulmonary vascular dilatations, which is found by transthoracic echocardiography with pre-existing liver cirrhosis. HPS severity was graded according to the value of partial pressure of arterial oxygen. The demographic characteristics and clinical outcomes between the HPS and non-HPS groups were compared. RESULTS A total of 181 patients were enrolled. Among them, 104 patients (57.5%) had HPS. The mean overall survival of HPS and non-HPS groups was 69.82±3.1 vs 63.36±3.8 months, with no significant difference (P=0.332). The overall survival between different degrees of HPS was also compared, and showed no significant difference (P=0.466). The HPS group had a higher incidence of delayed extubation (22.1% vs 10.4%, P=0.028) and chest pigtail catheter insertion (16.3% vs 10.4%, P=0.012). Nevertheless, it did not lead to a longer Intensive Care Unit/hospital stay or higher risk of short-term mortality. CONCLUSIONS Patients with HPS tend to have more post-LT pulmonary complications, but the overall survival is not adversely influenced, regardless of the severity of HPS.

Clinical and echocardiographic predictors of outcome in liver transplant patients

Liver transplant (LT) candidates undergo transthoracic echocardiography (TTE) before surgery to assess cardiac function and evaluate the echocardiographic probability of pulmonary hypertension (PHT). The improvement of pulmonary artery systolic pressure (PAPS) after transplant is associated with higher survival rates in patients with mild or moderate PHT. Although studies analyze the outcomes of LT in patients treated for PHT, the prognostic value of PAPS in patients without PHT in the follow-up is unknown. The aim of our study is to evaluate pre- and post-LT cardiac function, right ventricular function, pulmonary artery pressure, and their association with long-term mortality. 102 patients who underwent LT between 2011 and 2018 were compared for echocardiographic and hemodynamic parameters pre- and post-LT. After LT, systolic blood pressure, heart rate (HR), and PASP significantly increased, while tricuspid annular plane systolic excursion/PAPS decreased. Moreover, the higher difference in HR and PASP between pre- and post-LT was highlighted in those patients who died during the follow-up period after LT. Among all the parameters tested, in the multi-variable Cox regression for mortality, left ventricular ejection fraction and PASP difference were predictors of mortality. This study highlights the importance of TTE in LT screening as a tool to stratify patients at higher risk of death due to advanced cirrhotic cardiomyopathy and the importance of the change of echocardiographic parameters, in particular right and left ventricular hemodynamics, during the follow-up period. These parameters could be used to guide a more aggressive therapy.

Association of Cardiopulmonary Hemodynamics and Mortality in Veterans With Liver Cirrhosis: A Retrospective Cohort Study

BACKGROUND

Portopulmonary hypertension (PoPH), associated with increased mortality, can limit treatment options for liver diseases. Data on the continuum of clinical risk related to cardiopulmonary hemodynamics in PoPH are lacking.

METHODS AND RESULTS

As part of the United States national Veterans Affairs Clinical Assessment, Reporting, and Tracking database, we performed a retrospective cohort study of adults with cirrhosis undergoing right heart catheterization between October 1, 2017, and September 30, 2022. Pulmonary hypertension (mean pulmonary arterial pressure [mPAP] >20 mm Hg without PoPH) and PoPH (mPAP >20 mm Hg+pulmonary artery wedge pressure ≤15 mm Hg+pulmonary vascular resistance ≥3 WU) were defined by right heart catheterization hemodynamics. Multivariable Cox proportional hazards using natural splines for hemodynamic variables were used to evaluate the association between cardiopulmonary hemodynamics and mortality following right heart catheterization. A total of 4409 patients were included in the final analysis, predominantly men (96.3%), with a mean age of 68.5 years. Pulmonary hypertension and PoPH were observed in 71.6% and 10.2% of the cohort, respectively. Compared with a reference cardiac index of 2.5 L/min per m2, the hazard for mortality increased progressively with decreasing cardiac index, even after adjustment for mPAP and pulmonary vascular resistance. The minority of patients with PoPH (N=65, 14.5%) were prescribed pulmonary vasodilator therapy.

CONCLUSIONS

These data suggest that pulmonary hypertension and PoPH are prevalent in veterans with chronic liver disease, but low use of targeted PoPH therapy persists. Cardiac function discriminated mortality risk across a wide range of mPAP and pulmonary vascular resistance values and may diagnose and clarify prognosis in this patient population.

Anesthesia in patients with chronic liver disease: An updated review

Anesthesia in chronic liver disease patients can be challenging because of the medications given or interventions performed and their effects on liver physiology. Also, the effects of liver disease on coagulation and metabolism should be considered carefully. This review focuses on anesthesia in patients with different chronic liver disease stages. A literature search was performed for Scopus and PubMed databases for articles discussing different types of anesthesia in patients with chronic liver disease, their safety, usage, and risks. The choice of anesthesia is of crucial importance. Regional anesthesia, especially neuroaxial anesthesia, may benefit some patients with liver disease, but coagulopathy should be considered. Regional anesthesia provides optimum intraoperative relaxation and analgesia that extends to the postoperative period while avoiding the side effects of intravenous anesthetics and opioids. Pharmacodynamics and pharmacokinetics of anesthetic medications must guard against complications related to overdose or decreased metabolism. The choice of anesthesia in chronic liver disease patients is crucial and could be tailored according to the degree of liver compensation and the magnitude of the surgical procedure.

Struggling Between Liver Transplantation and Portopulmonary Hypertension

Portopulmonary hypertension (PoPH) is a progressive, ultimately fatal cardiopulmonary disease that occurs exclusively in patients with underlying portal hypertensive liver disease. PoPH outcomes are driven by both the severity of underlying liver disease and the degree of cardiac adaptation to elevated pulmonary pressures. The mainstay of treatment in PoPH is targeted pulmonary vascular therapy. Liver transplantation (LT) can be beneficial in some patients, but is associated with considerable risks in the PoPH population, and outcomes are variable. The optimal management strategy for PoPH, LT, or medical therapy alone, is unclear, and further research is needed to help guide clinical decision-making.

Shortness of breath due to portopulmonary hypertension and hepatopulmonary syndrome: diagnostic challenges and complex management approach in frail patients

A 60-year-old woman with a background of frailty, non-alcoholic fatty liver disease (NAFLD), cirrhosis and type 2 diabetes mellitus (T2DM), presented with worsening shortness of breath and a drop in oxygen saturation on sitting and standing up. Her chest X-ray demonstrated evidence of upper lobe venous diversion. Given the hypoxia, she had a computed tomography pulmonary angiography (CTPA) to rule out a pulmonary embolism. The only finding from the CTPA was pulmonary hypertension in the absence of any clots in the lungs. An ultrasound of the abdomen confirmed portal hypertension with splenomegaly and a cirrhotic liver, therefore, an initial diagnosis of portopulmonary hypertension and hepatopulmonary syndrome was made. The patient declined an agitated saline contrast echocardiography. Based on frailty she was not deemed to be a suitable candidate for a liver transplant and was discharged with a package of care alongside home oxygen therapy with periodic review in the gastroenterology clinic. She was assessed as stable with no new concerns while on home oxygen and diuretics. This case highlights challenges in diagnosing and managing patients with cirrhosis, portopulmonary hypertension and hepatopulmonary syndrome with a background of complex comorbidities and frailty.

An Overview of Circulating Pulmonary Arterial Hypertension Biomarkers

Pulmonary arterial hypertension (PAH), also known as Group 1 Pulmonary Hypertension (PH), is a PH subset characterized by pulmonary vascular remodeling and pulmonary arterial obstruction. PAH has an estimated incidence of 15-50 people per million in the United States and Europe, and is associated with high mortality and morbidity, with patients' survival time after diagnosis being only 2.8 years. According to current guidelines, right heart catheterization is the gold standard for diagnostic and prognostic evaluation of PAH patients. However, this technique is highly invasive, so it is not used in routine clinical practice or patient follow-up. Thereby, it is essential to find new non-invasive strategies for evaluating disease progression. Biomarkers can be an effective solution for determining PAH patient prognosis and response to therapy, and aiding in diagnostic efforts, so long as their detection is non-invasive, easy, and objective. This review aims to clarify and describe some of the potential new candidates as circulating biomarkers of PAH.

Insights on the Gut-Mesentery-Lung Axis in Pulmonary Arterial Hypertension: A Poorly Investigated Crossroad

Pulmonary arterial hypertension (PAH) is a life-threatening disease characterized by the hyperproliferation of vascular cells, including smooth muscle and endothelial cells. Hyperproliferative cells eventually obstruct the lung vasculature, leading to irreversible lesions that collectively drive pulmonary pressure to life-threatening levels. Although the primary cause of PAH is not fully understood, several studies have indicated it results from chronic pulmonary inflammation, such as observed in response to pathogens' infection. Curiously, infection by the intravascular parasite Schistosoma mansoni recapitulates several aspects of the widespread pulmonary inflammation that leads to development of chronic PAH. Globally, >200 million people are currently infected by Schistosoma spp., with about 5% developing PAH (Sch-PAH) in response to the parasite egg-induced obliteration and remodeling of the lung vasculature. Before their settling into the lungs, Schistosoma eggs are released inside the mesenteric veins, where they either cross the intestinal wall and disturb the gut microbiome or migrate to other organs, including the lungs and liver, increasing pressure. Spontaneous or surgical liver bypass via collateral circulation alleviates the pressure in the portal system; however, it also allows the translocation of pathogens, toxins, and antigens into the lungs, ultimately causing PAH. This brief review provides an overview of the gut-mesentery-lung axis during PAH, with a particular focus on Sch-PAH, and attempts to delineate the mechanism by which pathogen translocation might contribute to the onset of chronic pulmonary vascular diseases.

Multiple congenital visceral abnormalities as a rare cause of pulmonary arterial hypertension

Background

Pulmonary arterial hypertension (PAH) is a rare, progressive disorder. PAH is caused by a wide spectrum of pathologies but the cause remains undetermined on many occasions and patients are classified in the idiopathic group.

Case presentation

Here we report a young woman with rare congenital visceral abnormalities presenting with severe pulmonary hypertension.

Conclusions

Pulmonary hypertension is a complex disorder. Search for uncommon conditions that lead to pulmonary hypertension is necessary to determine the best management options.

Supplementary Information

The online version contains supplementary material available at 10.1186/s43044-022-00273-x.

Portopulmonary hypertension: a patient with shortness of breath

Portopulmonary hypertension (PoPH) is a poorly understood complication of liver disease which affects about 10% of patients with pulmonary hypertension. This case report outlines the difficulties in diagnosing and managing a patient with advanced disease, and the impact of these delays on the patient.PoPH has a significant risk of mortality with a 2-year survival rate of 67%. There are also few treatment options available and those which do exist are associated with multiple contraindications and risks. Patients with PoPH commonly present with dyspnoea, pulmonary hypertension and portal hypertension. The presence of coexisting chronic liver disease is also sometimes present. Traditional management for heart failure can temporarily alleviate symptoms but there is no proven long-term benefit. As a result, an understanding of the pathophysiology, diagnostics and management is crucial to ensure the best possible patient outcomes.

Progressive dyspnoea in a patient with idiopathic non-cirrhotic portal hypertension

This case of progressive dyspnoea in a 43-year-old with idiopathic non-cirrhotic portal hypertension highlights important pulmonary vascular complications of chronic liver diseasehttps://bit.ly/3rwEkhP

A case of sigmoidectomy for sigmoid colon cancer with severe pulmonary arterial hypertension associated with mixed tissue connected disease: A case report

Introduction

Patients with mixed connective tissue disease (MCTD) have higher rates of pulmonary arterial hypertension (PAH) than the general population. PAH is a risk for perioperative respiratory and heart failure, and marked edema of colonic stoma after sigmoidectomy. We report a case of sigmoidectomy for sigmoid colon cancer in a patient with PAH associated with MCTD for whom perioperative treatment was planned to control pulmonary arterial pressure (PAP), and a surgical strategy to avoid complications attributable to PAH and MCTD was employed.

Case presentation

A 52-year-old woman with sigmoid cancer and severe PAH associated with MCTD underwent surgery. We controlled PAH by using intravenous epoprostenol. We selected open surgery without laparoscopy and Hartmann's operation. After surgery, severe perioperative complications were not detected, and the patient discharged from hospital 17 days after the operation.

Discussion

During surgery under general anesthesia, the mortality rate of PAH is high because of heart and respiratory failure. We planned to switch the PAH treatment from an oral agent to intravenous epoprostenol only in the preoperative period, and selected open surgery. We ligated the inferior mesenteric artery (IMA) and inferior mesenteric vein (IMV) below the branch of LCA to avoid marked edema of stoma. Consequently, we could avoid severe intraoperative and postoperative complications.

Conclusions

Controlling PAP using epoprostenol, open surgery, stoma and the ligation level for the IMA and IMV preventing are important to avoid perioperative complications of sigmoid colon cancer complicated by severe PAH.

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The patient with PAH complicated by MCTD underwent Hartman’s operation for sigmoid colon cancer.

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Control of PAH by epoprostenol preoperatively is important to prevent perioperative cardiac complications.

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The level of ligation of the IMA and the LCA is important to avoid severe edema of stoma.

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.

Sildenafil Monotherapy to Treat Portopulmonary Hypertension Before Liver Transplant

Portopulmonary hypertension (PPHTN) is a rare complication of liver cirrhosis. Patients with severe PPHTN are contraindicated for liver transplant because of the associated risk of intraoperative acute right heart failure during reperfusion phase or massive volume infusion. Therefore, it has been recommended that patients with moderate to severe PPHTN undergo medical treatment to lower the pulmonary artery pressure before undergoing transplant. Herein, we report 3 patients with severe PPHTN who underwent sildenafil monotherapy before living donor liver transplant. None of the patients experienced associated adverse effects during sildenafil treatment, and the pulmonary artery pressure was effectively reduced before transplant. The first patient was diagnosed during anesthesia prior to transplant, and the mean pulmonary artery pressure was reduced by 34% after treatment. The second and third patients were followed-up with echography, and the estimated pulmonary artery systolic pressure were reduced by 34% and 47%, respectively. Pretransplant right heart catheterization also confirmed the reduction of the mean pulmonary artery pressure. Intraoperative hemodynamic parameters were stable, and the 3 patients were discharged uneventfully. After transplant, sildenafil was discontinued, and all patients remained in a stable clinical and functional status during follow-up.

Bone Morphogenetic Protein 9 Is a Mechanistic Biomarker of Portopulmonary Hypertension

RATIONALE

BMP9 (bone morphogenetic protein 9) is a circulating endothelial quiescence factor with protective effects in pulmonary arterial hypertension (PAH). Loss-of-function mutations in BMP9, its receptors, and downstream effectors have been reported in heritable PAH.

OBJECTIVES

To determine how an acquired deficiency of BMP9 signaling might contribute to PAH.

METHODS

Plasma levels of BMP9 and antagonist soluble endoglin were measured in group 1 PAH, group 2 and 3 pulmonary hypertension (PH), and in patients with severe liver disease without PAH.

MEASUREMENTS AND MAIN RESULTS

BMP9 levels were markedly lower in portopulmonary hypertension (PoPH) versus healthy control subjects, or other etiologies of PAH or PH; distinguished PoPH from patients with liver disease without PAH; and were an independent predictor of transplant-free survival. BMP9 levels were decreased in mice with PH associated with CCl₄-induced portal hypertension and liver cirrhosis, but were normal in other rodent models of PH. Administration of ALK1-Fc, a BMP9 ligand trap consisting of the activin receptor-like kinase-1 extracellular domain, exacerbated PH and pulmonary vascular remodeling in mice treated with hypoxia versus hypoxia alone.

CONCLUSIONS

BMP9 is a sensitive and specific biomarker of PoPH, predicting transplant-free survival and the presence of PAH in liver disease. In rodent models, acquired deficiency of BMP9 signaling can predispose to or exacerbate PH, providing a possible mechanistic link between PoPH and heritable PAH. These findings describe a novel experimental model of severe PH that provides insight into the synergy between pulmonary vascular injury and diminished BMP9 signaling in the pathogenesis of PAH.

Marked edema of colonic stoma after colectomy and severe pulmonary hypertension: Report of two cases

INTRODUCTION

Pulmonary hypertension (PH) is a disease with a poor prognosis and is a risk for perioperative heart and respiratory failure. Few reports exist regarding a colectomy performed in patients with PH. Herein, we report two cases of colectomy performed in patients with severe PH, accompanied with marked edema of the colonic stoma after surgery.

CASE PRESENTATION

In case 1, a 54-year-old patient with sigmoid cancer and severe primary PH underwent Hartmann's operation. After the operation, his stoma became markedly edematous and ulcerated. Swelling of the stoma became gradually reduced, and the patient was discharged from hospital 36 days after the operation. In case 2, a 62-year-old patient with upper rectal cancer and severe PH also underwent Hartmann's operation; his stoma became markedly edematous without ulceration.

CONCLUSION

Marked edema of the colonic stoma was observed in two cases with severe PH, with ulceration of the mucosa observed in one case. It was considered reasonable to avoid anastomosis in cases with severe PH.

Late complications of biliary atresia: hepatopulmonary syndrome and portopulmonary hypertension

Children with biliary atresia (BA) following Kasai portoenterostomy have a high risk for portal hypertension, however, while variceal and hemorrhagic complications have been more commonly studied, less frequent but no less possibly devastating complications of hepatopulmonary syndrome (HPS) and portopulmonary hypertension (PPH) remain less well understood. HPS and PPH both occur in a setting of portal hypertension, however, paradoxically patients with HPS develop pulmonic vasculature dilation leading to shunting and hypoxia, while those with PPH develop an opposite progression of pulmonary vasoconstriction eventually leading to cor pulmonale and decompensation. Given the near diametric evolution of diseases, HPS and PPH differ widely in therapy, though liver transplantation can have a role for treatment in either disease state. We reviewed our series of 320 pediatric patients with biliary atresia treated at our institution over 44 years, highlighting two cases that developed HPS and PPH, respectively, using these cases in further discussion of hepatopulmonary syndrome and portopulmonary hypertension regarding disease etiology, diagnosis, management, and prognosis. The complicated nature of these processes demand a careful multidisciplinary approach to optimize patient outcomes, including mindful evaluation for when transplantation may offer benefit.

Mutational screening in genes related with porto-pulmonary hypertension: An analysis of 6 cases

INTRODUCTION

Portopulmonary hypertension (PPH) is a rare disease with a low incidence and without a clearly-identified genetic component. The aim of this work was to check genes and genetic modifiers related to pulmonary arterial hypertension in patients with PPH in order to clarify the molecular basis of the pathology.

PATIENTS

We selected a total of 6 patients with PPH and amplified the exonic regions and intronic flanking regions of the relevant genes and regions of interest of the genetic modifiers.

RESULTS

Six patients diagnosed with PPH were analyzed and compared to 55 healthy individuals. Potentially-pathogenic mutations were identified in the analyzed genes of 5 patients. None of these mutations, which are highly conserved throughout evolution, were detected in the control patients nor different databases analyzed (1000 Genomes, ExAC and DECIPHER). After analyzing for genetic modifiers, we found different variations that could favor the onset of the disease.

CONCLUSIONS

The genetic analysis carried out in this small cohort of patients with PPH revealed a large number of mutations, with the ENG gene showing the greatest mutational frequency.

[Portopulmonary hypertension: Updated review]

Portopulmonary hypertension (PPH) is a rare condition worldwide, although epidemiological data are unknown in Mexico. However, chronic liver diseases are very prevalent in Mexico. PPH is the 4th subtype in frequency in the group of pulmonary arterial hypertension. Its diagnosis is made within 2 scenarios: patients with suspected pulmonary hypertension and candidates for orthotopic liver transplantation (OLT). Both echocardiogram and a right cardiac catheterisation are crucial for diagnosis in both cases. PPH is a challenge for OLT, since it can significantly increase perioperative mortality. The use of specific therapy is the cornerstone of this disease, as a measure to improve the outcome of those who become candidates for OLT with moderate to severe PPH. It is important to recognise that PPH can be a contraindication to OLT. The role of lung-liver transplantation or heart-lung-liver transplantation as a measure to heal pulmonary vascular disease in patients with PPH is still uncertain.

Role of oxidized lipids in pulmonary arterial hypertension

Pulmonary arterial hypertension (PAH) is a multifactorial disease characterized by interplay of many cellular, molecular, and genetic events that lead to excessive proliferation of pulmonary cells, including smooth muscle and endothelial cells; inflammation; and extracellular matrix remodeling. Abnormal vascular changes and structural remodeling associated with PAH culminate in vasoconstriction and obstruction of pulmonary arteries, contributing to increased pulmonary vascular resistance, pulmonary hypertension, and right ventricular failure. The complex molecular mechanisms involved in the pathobiology of PAH are the limiting factors in the development of potential therapeutic interventions for PAH. Over the years, our group and others have demonstrated the critical implication of lipids in the pathogenesis of PAH. This review specifically focuses on the current understanding of the role of oxidized lipids, lipid metabolism, peroxidation, and oxidative stress in the progression of PAH. This review also discusses the relevance of apolipoprotein A-I mimetic peptides and microRNA-193, which are known to regulate the levels of oxidized lipids, as potential therapeutics in PAH.

Successful Liver Transplant Complicated by Severe Portopulmonary Hypertension After an Initial Aborted Attempt: Case Report and Review of Treatment Options

Good right ventricular function and responsiveness to vasodilator therapy are the most important prerequisites for successful liver transplant in patients with portopulmonary hypertension. A patient with portopulmonary hypertension and good right ventricular function presented for deceased-donor liver transplant. Pulmonary arterial pressure was controlled with epoprostenol and sildenafil preoperatively. After anesthesia induction, pulmonary arterial pressure increased significantly and the procedure was aborted. Additional medical treatment included aggressive vasodilator therapy and the transplant was successfully performed 1 month later. During the procedure, elevations in pulmonary arterial pressure responded to a combination of inhaled nitric oxide, intravenous milrinone and nitroglycerin, and optimization of mechanical ventilation.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Portopulmonary hypertension

Portopulmonary hypertension (POPH) is defined as pulmonary arterial hypertension (PAH) complicated by portal hypertension, with or without advanced hepatic disease. Significant percentage of patients with cirrhotic liver disease has high cardiac output and subsequently elevated pulmonary arterial pressures (PAP). However, patients with POPH develop a progressive increase in pulmonary vascular resistance (PVR), which is generally lower than that observed in other forms of PAH.

The prognosis of untreated patients with POPH is very poor and the outcome of liver transplant (LT) in those patients is determined by the degree of severity of the associated pulmonary hemodynamics.

In this narrative review, we describe the clinical presentation of POPH, the pathobiology, and the clinical implication of pulmonary hemodynamics. We also provide evidence-based recommendations for the diagnosic and management approaches of POPH.

Pharmacokinetics and tissue distribution of spray-dried carboplatin microspheres: lung targeting via intravenous route

For cancer therapy, microspheres can be used to increase effectiveness while decreasing side effects of treatments. We prepared gelatin microspheres containing carboplatin (GCPtM) for treating lung cancer. We prepared gelatin microspheres of carboplatin (GCPtM) for use in treating lung cancer. Microspheres were prepared using a Buchi B-90 nano spray-drier. Surface morphology was found to be shriveled to nearly spherical, with an average size of 14.7 μm. Drug loading and percentage yield were found to be 72 ± 0.4 and 88 ± 0.2 %, respectively. In vitro release studies indicated that diffusion followed the Peppas model, with 99.3 % of total carboplatin released from GCPtM after 12 h, while for the pure drug this value was 92.4 % in 0.5 h. Liquification was observed during stability studies at 37 °C with an relative humidity of 75 %. Plasma concentration profile was described using a two-compartment model after intravenous injection of GCPtM. Carboplatin containing microspheres distributed in the lung, spleen, liver, and blood were found to be primarily distributed in the lungs. We used a powder technology (spray-dryer) method in this study to significantly reduce the overall production time and desired particle size, without using organic solvents; additionally, this method is economically feasible. Thus, microsphere may be an effective method for successfully delivering carboplatin to the lungs.