Dyspnea and respiratory muscle strength in end-stage liver disease

Pulmonary Dysfunction in Patients with Cirrhosis of the Liver: A Study of Pulmonary Function Tests and Arterial Blood Gases

Background and Aim

Respiratory complications in liver cirrhosis can occur due to various mechanisms, such as ascites causing restricted lung expansion and opening of intrapulmonary vascular shunts due to high portal pressures. We aimed to study the effects of the liver dysfunction on the lungs by evaluating arterial blood gas (ABG) and pulmonary function test (PFT) of all study subjects.

Subjects and Methods

A cross-sectional study was done between August 2020 and September 2022. Diagnosed cases of the liver cirrhosis were enrolled in the study after informed consent and were subjected to the following investigations: chest X-ray, oximetry, spirometry, diffusing capacity of the lung for carbon monoxide (DLCO), two-dimensional echocardiography, and ABG analysis (ABGA). The cases were divided into three groups based on their Child-Pugh staging, and statistical analysis was done on the collected data.

Results

A total of 64 (53 males and 11 females) patients with an average age of 49.82 ± 9.89 years were studied. Alcoholism was the most common cause of cirrhosis in males. Breathlessness (65.6%) and pleural effusion (26.6%) were the most common respiratory symptoms and signs, respectively. Seventeen patients had hepatic hydrothorax, eight patients had hepatopulmonary syndrome (HPS), and six patients had portopulmonary hypertension. Low pH (17.2%) and oxygen partial pressure (PaO2) (20.3%) were the most common ABGA findings. The pH, PaO2, forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC), and DLCO were significantly low in Child Pugh Stage C (P < 0.05). The pH, pO2, HCO3, FEV1, FVC, FEV1/FVC, and DLCO were significantly lower in patients with HPS (P < 0.05).

Conclusion

Metabolic acidosis and low FEV1/FVC and DLCO were the common findings in study subjects. Pulmonary dysfunction was common in advanced liver cirrhosis. Patients with HPS had worse ABG and PFT parameters than those without HPS.

Acid Base Disorders in Cirrhosis

Metabolic and respiratory acid-base disorders are common in individuals with liver disease and cirrhosis. The most common disorder is respiratory alkalosis, which may be related to dyspnea or respiratory stimulation. Primary metabolic disorders are less common. Although the liver plays a role in metabolism of amino acids and generation of acid from dietary sources, it does not play a role in the regulation of pH. Instead, metabolic disorders may arise from alterations in normal metabolism or from medications, particularly diuretics and osmotic laxatives, used in the treatment of these complex patients. Understanding the mechanistic underpinnings of these disorders can aid in the management of individuals with liver disease in the hospital and in outpatient settings.

Pulmonary function testing in patients with liver cirrhosis (Review)

Liver cirrhosis is a common long-term outcome of chronic hepatic inflammation. Patients with liver cirrhosis may also have pulmonary complications. There are several reasons for pulmonary dysfunction in liver cirrhosis, including intrinsic cardiopulmonary dysfunction unrelated to liver disease and specific disorders related to the presence of liver cirrhosis and/or portal hypertension. The most prevalent and clinically significant pulmonary complications are hepatic hydrothorax, hepatopulmonary syndrome, spontaneous pulmonary empyema and portopulmonary hypertension. Pulmonary function tests (PFTs) have traditionally been used to assess the lung function of patients with liver cirrhosis. To the best of our knowledge, the present review is the first to detail all types of PFTs performed in patients with liver cirrhosis and discuss their clinical significance. Patients with liver cirrhosis have reduced values of spirometric parameters, diffusion capacity for carbon monoxide (DLCO), lung volumes, maximal inspiratory pressure and maximal expiratory pressure. Furthermore, they have a higher closing volume, a greater airway occlusion pressure 0.1 sec after the onset of inspiratory flow and greater exhaled nitric oxide values. In order to improve pulmonary function, patients with ascites may require therapeutic paracentesis. Such findings should be considered when evaluating individuals with liver disease, particularly those who may require surgery. Poor lung function, particularly restrictive lung disease, can have an impact on post-transplant outcomes, such as ventilator time, length of hospital duration and post-operative pulmonary complications; thus, the transplant care team needs to be aware of its prevalence and relevance.

Targets and study design for symptom-focused trials aimed at patients with cirrhosis: An expert consensus

BACKGROUND

Symptom-focused trials are critically needed for patients with cirrhosis. However, this work would benefit from standard processes and validated measures.

METHODS

A writing group was formed among hepatologists, nurses, palliative care providers, pharmacists, and clinical trial experts focused on symptom management in patients with cirrhosis to define the key (1) components of trial design, (2) symptom targets, (3) measurement, and (4) outcomes for each target. From July 2022 to January 2023, panelists participated in an iterative process of developing and arriving at a consensus for each component. The goal was to provide consensus definitions that can be operationalized in future clinical trials, including for patients with cirrhosis.

RESULTS

The panel reached a consensus on key reporting features for clinical trials, along with considerations for study design. Nine key symptom targets (muscle cramps, pruritus, pain, fatigue, sexual dysfunction, sleep disorders, depression and anxiety, nausea/vomiting, and dyspnea/breathlessness) were identified. The panel selected instruments that can be considered for clinical trials based on psychometric validation and previous experience. The panel identified ongoing needs, including instrument validation, safety data, evidence about non-pharmacologic interventions, and comparative effectiveness studies.

CONCLUSION

This expert panel identified key design, reporting, and measurement elements to standardize processes and measures in future symptom-focused clinical trials in the context of cirrhosis.

Acid-base abnormalities and liver dysfunction

In addition to the kidneys and lungs, the liver also plays an important role in the regulation of the Acid-Base Equilibrium (ABE). The involvement of the liver in the regulation of ABE is crucial because of its role in lactic acid metabolism, urea production and in protein homeostasis. The main acid-base imbalance that occurs in patients with liver cirrhosis is Respiratory Alkalosis (RAlk). Due to the fact that in these patients additional pathophysiological mechanisms that affect the ABE are present, other disorders may appear which compensate or enhance the primary disorder. Conventional ABE reading models fail to identify and assess the underlying disorders in patients with liver cirrhosis. This weakness of the classical models led to the creation of new physicochemical mathematical models that take into account all the known parameters that develop and affect the ABE. In addition to the RAlk, in patients with liver cirrhosis, metabolic alkalosis (due to hypoalbuminemia), hyponatremic metabolic acidosis, hyperchloremic metabolic acidosis, lactic acidosis and metabolic alkalosis due to urea metabolism are some of the pathophysiological mechanisms that affect the ABE.

Urinary BA Indices as Prognostic Biomarkers for Complications Associated with Liver Diseases

Hepatobiliary diseases and their complications cause the accumulation of toxic bile acids (BA) in the liver, blood, and other tissues, which may exacerbate the underlying condition and lead to unfavorable prognosis. To develop and validate prognostic biomarkers for the prediction of complications of cholestatic liver disease based on urinary BA indices, liquid chromatography-tandem mass spectrometry was used to analyze urine samples from 257 patients with cholestatic liver diseases during a 7-year follow-up period. The urinary BA profile and non-BA parameters were monitored, and logistic regression models were used to predict the prognosis of hepatobiliary disease-related complications. Urinary BA indices were applied to quantify the composition, metabolism, hydrophilicity, and toxicity of the BA profile. We have developed and validated the bile-acid liver disease complication (BALDC) model based on BA indices using logistic regression model, to predict the prognosis of cholestatic liver disease complications including ascites. The mixed BA and non-BA model was the most accurate and provided higher area under the receiver operating characteristic (ROC) and smaller akaike information criterion (AIC) values compared to both non-BA and MELD (models for end stage liver disease) models. Therefore, the mixed BA and non-BA model could be used to predict the development of ascites in patients diagnosed with liver disease at early stages of intervention. This will help physicians to make a better decision when treating hepatobiliary disease-related ascites.

Sleep disorder in patients with chronic liver disease: a narrative review

Sleep disturbance is a common feature of chronic liver disease (CLD) with impact on health-related quality of life; 60-80% of patients with CLD report subjective poor sleep; frequent presentations of sleep disturbance include insomnia, reduced sleep efficiency, increased sleep latency, reduced time in rapid eye movement (REM) sleep, restless leg syndrome and excessive daytime sleepiness (EDS). Key contributors to sleep disturbance include hepatic encephalopathy (HE) and circadian rhythm imbalance due to altered melatonin metabolism. Specific conditions causing CLD, such as non-alcoholic fatty liver disease (NAFLD), chronic viral hepatitis and primary biliary cholangitis (PBC) result in different types of sleep disturbance, and the treatment of these conditions can often also lead to sleep disturbance. There are currently limited management options for sleep disturbance in CLD. Obstructive sleep apnoea (OSA) is a common condition that causes chronic intermittent hypoxia due to airway collapse during sleep. This chronic intermittent hypoxia appears to contribute to the development of NAFLD. The presence of reactive oxygen species and the overexpression of hypoxia inducible factor 1-alpha secondary to hypoxia may be responsible for the second 'hit' of the 'two-hit' hypothesis of NAFLD. Treatment of the intermittent hypoxia with continuous positive airway pressure therapy has limited efficacy against liver dysfunction. There remain many outstanding areas of investigation in the management of sleep disturbance in CLD, and of liver dysfunction in OSA.

Applications of a novel radiotelemetry method for the measurement of intrathoracic pressures and physiological rhythms in freely behaving mice

Techniques to comprehensively evaluate pulmonary function carry a variety of limitations, including the ability to continuously record intrathoracic pressures (ITP), acutely and chronically, in a natural state of freely behaving animals. Measurement of ITP can be used to derive other respiratory parameters, which provide insight to lung health. Our aim was to develop a surgical approach for the placement of a telemetry pressure sensor to measure ITP, providing the ability to chronically measure peak pressure, breath frequency, and timing of the respiratory cycle to facilitate circadian analyses related to breathing patterns. Applications of this technique are shown using a moderate hypoxic challenge. Male C57Bl/6 mice were implanted with radiotelemetry devices to record heart rate, temperature, activity, and ITP during 24-h normoxia, 24-h hypoxia ([Formula: see text] = 0.15), and return to 48-h normoxia. Radiotelemetry of ITP permitted the detection of hypoxia-induced increases in "the ITP equivalent" of ventilation, which were driven by increases in breathing frequency and ITP on a short-term time scale. Respiratory frequency, derived from pressure waveforms, was increased by a decrease in expiratory time without changes in inspiratory time. Chronically, telemetric recording allowed for circadian analyses of respiratory drive, as assessed by inspiratory pressure divided by inspiratory time, which was increased by hypoxia and remained elevated for 48 h of recovery. Furthermore, respiratory frequency demonstrated a circadian rhythm, which was disrupted through the recovery period. In conclusion, radiotelemetry of ITP is a viable, long-term, chronic methodology that extends traditional methods to evaluate respiratory function in mice.NEW & NOTEWORTHY We have demonstrated for the first time in mice that radiotelemetry is an effective tool for the continuous and chronic recording of intrathoracic pressure (ITP) to facilitate circadian rhythm analyses. We show that continuous 24-h hypoxic stress alters the circadian rhythms of heart rate, body temperature, activity, and respiratory parameters, acutely and perpetually, through normoxic recovery. Radiotelemetry of ITP can complement traditional methods for evaluating respiratory function and better our understanding of respiratory pathophysiology.

A scoping review to identify and map the multidimensional domains of pain in adults with advanced liver disease

Background: Pain is a significant problem in adults living with advanced liver disease, having limited guidance available for its clinical management. While pain is considered a multidimensional experience, there have been limited reviews of the pain literature in advanced liver disease conducted with a multidimensional framework. Aims: The goal of this scoping review was to identify and map the multidimensional domains of pain in adults with advanced liver disease using the biopsychosocial model. Methods: We used Arksey and O'Malley's scoping framework. A search was conducted in MEDLINE, Embase, AMED, and CINAHL databases and the gray literature using specific eligibility criteria (1990-2019). Citation selection and data extraction were performed by two independent reviewers and in duplicate. Results: Of the 43 studies that met inclusion criteria, 51% were from North America and 93% utilized quantitative methods. The combined studies reported on 168,110 participants with ages ranging between 23 to 87 years. Only 9% reported an objective scoring system for liver disease severity. Few studies reported pain classification (9%) and intensity (16%). Pain prevalence ranged between 18% and 100%, with pain locations including joint, abdomen, back, head/neck, and upper/lower extremities. We identified and mapped 115 pain factors to the biopsychosocial model: physical (81%), psychological (65%), and sociocultural (5%). Only 9% measured pain using validated multidimensional tools. Pharmacological intervention (92%) prevailed among pain treatments. Conclusions: Pain is not well understood in patients with advanced liver disease, having limited multidimensional pain assessment and treatment approaches. There is a need to systematically examine the multidimensional nature of pain in this population.

The Relationship Between Airway Occlusion Pressure and Severity of liver Cirrhosis in Candidates for Liver Transplantation

BACKGROUND End-stage cirrhosis is an irreversible condition, and liver transplantation is the only treatment option in for the affected patients. Respiratory problems and abnormal breathing are common findings among these patients. In this study, for the first time, we examined the relationship between the severity of liver cirrhosis and respiratory drive measured by mouth occlusion pressure (P_0.1). METHODS This was a cross-sectional study conducted on 50 candidates for liver transplantation who were referred to the pulmonary clinic of Imam Khomeini Hospital for pre-operative pulmonary evaluations. Arterial blood gas analysis (ABG), pulmonary function tests, and measurement of P0.1 were performed for all patients. The severity of liver disease was assessed using the Model for End-Stage Liver Disease (MELD) score. RESULTS The median P_0.1 was 5 cm H₂ O. P_0.1 was negatively associated with PaCO₂ (r = -0.466, p = 0.001) and HCO3 - (r = -0.384, p = 0.007), and was positively correlated with forced expiratory volume at 1s (FEV1 )/ forced vital capacity (FVC) (r = 0.282, p = 0.047). There was a strong correlation between P_0.1 and MELD score (r = 0.750, p < 0.001). Backward multivariate linear regression revealed that a higher MELD score and lower PaCO₂ were associated with increased P_0.1. CONCLUSION High levels of P_0.1 and strong direct correlation between P_0.1 and MELD score observed in the present study are suggestive of the presence of abnormal increased respiratory drive in candidates for liver transplantation, which is closely related to their disease severity.

ASSOCIATION BETWEEN FATIGUE AND EXERCISE CAPACITY IN PATIENTS WITH CHRONIC LIVER DISEASE AWAITING LIVER TRANSPLANTATION

BACKGROUND

Fatigue is highly prevalent in end stage liver disease, the studies about its association with exercise capacity in cirrhotic patients before liver are scarse.

OBJECTIVE

In this study, we evaluated fatigue in 95 in end stage liver disease patients awaiting transplantation, compared to healthy volunteers, and tested the association between exercise capacity and fatigue.

METHODS

Cross-sectional study of patients with chronic liver disease treated at a referral center in Fortaleza, Brazil. Fatigue was quantified with the Fatigue Severity Scale. The patients were submitted to the 6-min walk test, the 6-min step test, the Hospital Anxiety and Depression Scale, C-reative protein measurement and hematocrit count, measurement of dyspnea among other tests. Fatigue data were obtained from healthy individuals for comparison with patients.

RESULTS

The mean age of patients was 45.9±12.3 years, and 53.7% were male. Fatigue, anxiety and depression levels were higher among end stage liver disease patients than among controls. A negative correlation was observed between 6 min step test and Fatigue Severity Scale score (r= -0.2; P=0.02) and between hematocrit count and Fatigue Severity Scale score (r= -0.24; P=0.002). Dyspnea on the Borg scale and fatigue were positively correlated (r=31; P=0.002). In the multivariate analysis, low 6-min step test values and high levels of dyspnea were associated with fatigue.

CONCLUSION

Fatigue was more prevalent and severe in end stage liver disease patients than in healthy controls. Low 6MST values and high levels of dyspnea were associated with fatigue in this scenario.

Symptom prevalence and quality of life of patients with end-stage liver disease: A systematic review and meta-analysis

BACKGROUND:

End-stage liver disease is a common cause of morbidity and mortality worldwide, yet little is known about its symptomatology and impact on health-related quality of life.

AIM:

To describe symptom prevalence and health-related quality of life of patients with end-stage liver disease to improve care.

DESIGN:

Systematic review.

DATA SOURCES:

We searched eight electronic databases from January 1980 to June 2018 for studies investigating symptom prevalence or health-related quality of life of adult patients with end-stage liver disease. No language restrictions were applied. Meta-analyses were performed where appropriate.

RESULTS:

We included 80 studies: 35 assessing symptom prevalence, 41 assessing health-related quality of life, and 4 both. The instruments assessing symptoms varied across studies. The most frequently reported symptoms were as follows: pain (prevalence range 30%–79%), breathlessness (20%–88%), muscle cramps (56%–68%), sleep disturbance (insomnia 26%–77%, daytime sleepiness 29.5%–71%), and psychological symptoms (depression 4.5%–64%, anxiety 14%–45%). Erectile dysfunction was prevalent (53%–93%) in men. The health-related quality of life of patients with end-stage liver disease was significantly impaired when compared to healthy controls or patients with chronic liver disease. Compared with compensated cirrhosis, decompensation led to significant worsening of both components of the 36-Item Short Form Survey although to a larger degree for the Physical Component Summary score (decrease from average 6.4 (95% confidence interval: 4.0–8.8); p < 0.001) than for the Mental Component Summary score (4.5 (95% confidence interval: 2.4–6.6); p < 0.001).

CONCLUSION:

The symptom prevalence of patients with end-stage liver disease resembled that of patients with other advanced conditions. Given the diversity of symptoms and significantly impaired health-related quality of life, multidisciplinary approach and timely intervention are crucial.

Psychiatric Comorbidity, Health-Related Quality of Life, and Mental Health Service Utilization Among Patients Awaiting Liver Transplant

CONTEXT

The prevalence of psychiatric disorders and mental health service utilization among patients with end-stage liver disease awaiting transplant remains understudied.

OBJECTIVES

This study assessed the prevalence of psychological disorders and symptoms with the use of a structured diagnostic interview and self-report measures, and examined patient-reported mental health service utilization and barriers to care.

METHODS

Waitlisted liver transplant candidates (N = 120) completed assessments during routine clinic appointments at a single time point.

RESULTS

Participants endorsed moderate-to-severe levels of depression (19.2%), anxiety (26.7%), and Post Traumatic Stress Disorder (PTSD) (23.3%). Forty-three percent had received some form of mental health treatment in the recent past, and a range of barriers to accessing mental health services were endorsed. In a subset of 39 participants who received a structure diagnostic assessment, there was a high prevalence of current (51.3%) and past (82.1%) psychiatric disorders. Elevated scores on depression, anxiety, and PTSD measures were associated with significant decrements in health-related quality of life, but were not differentially associated with mental health service utilization.

CONCLUSION

There are a significant number of end-stage liver disease patients who could benefit from intervention who are not currently connected to treatment. Many patients do not see the need for accessing services, perhaps because of a lack of insight or knowledge about the benefits of mental health treatment. Future research should determine optimal treatment and service delivery methods for this vulnerable population.

Hepatopulmonary Syndrome: Oxidative Stress and Physical Exercise

Hepatopulmonary syndrome (HPS) may be defined by hepatic disease, gas exchange abnormalities that may lead to hypoxaemia, and the presence of pulmonary vascular dilations. The balance between the many substances involved in vasodilation and vasoconstriction is regulated by the liver; thus, liver damage may generate systemic changes throughout the body. The pulmonary tissue may be damaged by reactive oxygen species or nitric oxide. Dyspnoea is the most frequent pulmonary symptom, caused by tissue damage, and may become worse when an individual exercises. In experimental research the surgical model of bile duct ligation is the optimal model to simulate the typical lung alterations present in HPS, which results in an increase in oxidative stress in hepatic and pulmonary tissues. In liver injury, the muscular system may also be damaged, for example sarcopenia may seriously aggravate cirrhosis and is associated with cirrhotic patient mortality. Muscular changes can be explained by the actions of myostatin and insulin-like growth factor and the increase in body levels of ammonia. As a result of impaired cardiopulmonary and muscular conditions, HPS patients may exhibit a low exercise tolerance, low muscle strength, and low functionality. Liver disease can contribute to HPS oxidative stress and is one of the main factors responsible for the reduction of gas exchange. Physical exercise can be performed as a way of modifying this pathophysiological state. Studies that have investigated physical exercise as a therapy for cirrhosis suggest that this approach may be beneficial for cirrhotic patients, primarily with regard to muscular and cardiorespiratory injuries.

Acid-base disorders in liver disease

Alongside the kidneys and lungs, the liver has been recognised as an important regulator of acid-base homeostasis. While respiratory alkalosis is the most common acid-base disorder in chronic liver disease, various complex metabolic acid-base disorders may occur with liver dysfunction. While the standard variables of acid-base equilibrium, such as pH and overall base excess, often fail to unmask the underlying cause of acid-base disorders, the physical-chemical acid-base model provides a more in-depth pathophysiological assessment for clinical judgement of acid-base disorders, in patients with liver diseases. Patients with stable chronic liver disease have several offsetting acidifying and alkalinising metabolic acid-base disorders. Hypoalbuminaemic alkalosis is counteracted by hyperchloraemic and dilutional acidosis, resulting in a normal overall base excess. When patients with liver cirrhosis become critically ill (e.g., because of sepsis or bleeding), this fragile equilibrium often tilts towards metabolic acidosis, which is attributed to lactic acidosis and acidosis due to a rise in unmeasured anions. Interestingly, even though patients with acute liver failure show significantly elevated lactate levels, often, no overt acid-base disorder can be found because of the offsetting hypoalbuminaemic alkalosis. In conclusion, patients with liver diseases may have multiple co-existing metabolic acid-base abnormalities. Thus, knowledge of the pathophysiological and diagnostic concepts of acid-base disturbances in patients with liver disease is critical for therapeutic decision making.

Clinical Impact of Intrapulmonary Vascular Dilatation in Candidates for Liver Transplant

BACKGROUND

Intrapulmonary vascular dilatations (IPVD) frequently are detected in patients with liver disease by the delayed appearance of microbubbles at contrast-enhanced echocardiography. IPVD with an elevated alveolar-arterial (A-a) gradient define hepatopulmonary syndrome (HPS); however, the importance of IPVD in the absence of abnormal gas exchange is unknown. We aimed to determine the clinical impact of IPVD in patients with liver disease.

METHODS

We performed a cross-sectional study within the Pulmonary Vascular Complications of Liver Disease 2 Study, a multicenter, prospective cohort study of patients being evaluated for liver transplant. We excluded patients with obstructive or restrictive lung disease, HPS, or intracardiac shunting. We compared patients with and those without IPVD.

RESULTS

Forty-six patients with IPVD and 81 patients without IPVD were included. Patients with IPVD were more likely to have autoimmune hepatitis and less likely to have cryptogenic cirrhosis and hepatocellular carcinoma. Patients with IPVD had higher Child-Pugh scores (6 [interquartile range (IQR), 5-7] vs 5 [IQR, 4-7]; P = .04), possibly higher Model for End-Stage Liver Disease scores (14.5 [IQR, 11.6-15.8] vs 12.2 [IQR, 9.4-15.5]; P = .06), higher PaO₂ levels (97.9 [IQR, 92.0-103.0] vs 89.0 [IQR, 82.0-96.9] mm Hg; P < .001), and lower A-a gradients (9.9 [IQR, 6.2-13.5] vs 14.9 [IQR, 9.0-21.8] mm Hg; P < .001). Symptoms and quality of life were similar between the groups.

CONCLUSIONS

Autoimmune hepatitis and increased liver disease severity were associated with the presence of IPVD, which was characterized by higher PaO₂ levels. Future studies to better characterize IPVD pathogenesis and the relationship of IPVD to HPS are warranted.

Electrolyte and Acid-Base Disturbances in End-Stage Liver Disease: A Physiopathological Approach

Electrolyte and acid-base disturbances are frequent in patients with end-stage liver disease; the underlying physiopathological mechanisms are often complex and represent a diagnostic and therapeutic challenge to the physician. Usually, these disorders do not develop in compensated cirrhotic patients, but with the onset of the classic complications of cirrhosis such as ascites, renal failure, spontaneous bacterial peritonitis and variceal bleeding, multiple electrolyte, and acid-base disturbances emerge. Hyponatremia parallels ascites formation and is a well-known trigger of hepatic encephalopathy; its management in this particular population poses a risky challenge due to the high susceptibility of cirrhotic patients to osmotic demyelination. Hypokalemia is common in the setting of cirrhosis: multiple potassium wasting mechanisms both inherent to the disease and resulting from its management make these patients particularly susceptible to potassium depletion even in the setting of normokalemia. Acid-base disturbances range from classical respiratory alkalosis to high anion gap metabolic acidosis, almost comprising the full acid-base spectrum. Because most electrolyte and acid-base disturbances are managed in terms of their underlying trigger factors, a systematic physiopathological approach to their diagnosis and treatment is required.

Association Between Dyspnea and Severity of Liver Disease in Patients in the Pre-transplantation Period-A Pilot Study

BACKGROUND

Liver transplantation is indicated at the end stage of chronic liver failure, and severity of disease will determine the precocity of this happening. At this stage, the presence of chronic dyspnea is one of several manifestations of progression of the disease, which leads the patient to inactivity. A rehabilitation program can positively influence the evolution of liver transplant recipients. The objective of this study was to establish an association between the perception of dyspnea and the severity of liver disease in patients at a single center of a Brazilian liver pre-transplantation clinic.

METHODS

Measurements were performed at a liver pre-transplantation clinic. The severity of liver disease was assessed with the use of the Model for End-Stage Liver Disease (MELD) score, and dyspnea was assessed with the use of a modified Medical Research Council scale of dyspnea (mMRC).

RESULTS

Men had a higher prevalence of viral hepatitis. Dyspnea was reported only during intense exercise. Duration of disease and MELD score showed medians of 49 months and 20, respectively.

CONCLUSIONS

We found no correlation between mMRC and the MELD score. In addition, no correlation was found between duration of disease and MELD score or mMRC.

Thoracic perspective revisited in chronic liver disease

A variety of chest manifestations are seen in patients with chronic liver diseases, namely hepatopulmonary syndrome, portopulmonary hypertension, intrathoracic portosystemic collaterals, hepatic hydrothorax, infections, drug-induced changes, manifestations of hepatocellular carcinoma, gynecomastia, acute respiratory distress syndrome, autoimmune changes, aspiration pneumonitis and changes due to α₁-antitrypsin deficiency. Gastroenterologists and radiologists should be aware of these entities; knowledge of the imaging findings specific to each condition is of prime importance for managing such patients.