The role of chronic alcohol abuse in the development of acute respiratory distress syndrome in adults

The association between alcohol consumption and pulmonary function: a scoping review

INTRODUCTION

The health effects of alcohol are well established but the influence on pulmonary function remains debated. Studies indicate that small amounts of alcohol are beneficial and heavy consumption is harmful, suggesting a U-shaped association. Our objective is to determine whether there is an association between alcohol intake and changes in pulmonary function parameters, exploring the potential protective effect of moderate alcohol consumption and the harm caused by heavy drinking.

METHODS

A comprehensive search from PubMed, Embase, Cochrane and CINAHL was carried out, and studies were evaluated using the JBI methodological framework for scoping reviews. Two independent reviewers conducted parallel screening and data extraction. A data extraction form was utilised to organise key themes, with qualitative analysis and visual representation of the results.

RESULTS

Among 4427 screened abstracts, 179 underwent full-text review, resulting in 30 eligible studies. Of these, 10 showed a negative effect, nine reported no impact, nine exhibited a positive effect and two indicated a nonlinear U-shaped association between alcohol consumption and pulmonary function parameters.

CONCLUSION

While the U-shaped curve hypothesis remains unconfirmed by the current literature, there are notable associations. Heavy alcohol consumption appears to negatively affect pulmonary function, while low to moderate intake shows a positive influence in included studies. However, the diversity in study quality, the nonstandardised alcohol intake quantification and the confounding role of smoking challenge definitive conclusions. The need for consistent, long-term international studies is evident to further explore this relationship while addressing the complex interplay between alcohol and smoking.

Alcohol and its metabolites dysregulate cellular bioenergetics and induce oxidative and endoplasmic reticulum stress in primary human bronchial epithelial cells

BACKGROUND

Chronic alcohol consumption/misuse is a significant risk factor for pneumonia and lung infection leading to the development of chronic pulmonary disorders such as chronic obstructive pulmonary disease (COPD) and lung fibrosis. In this study, we sought to delineate the mechanism of alcohol-associated lung disease. We did so by measuring in vitro mitochondrial, endoplasmic reticulum (ER) oxidative stress in human bronchial epithelial cells (hBECs) treated with ethanol and its oxidative (acetaldehyde) and nonoxidative (fatty acid ethyl esters or FAEEs) metabolites.

METHODS

Primary hBECs from a normal subject were treated with relevant concentrations of ethanol and its metabolites and incubated at 37°C for 24 h. Viability and cytotoxicity were determined using cell viability and lactate dehydrogenase (LDH) assay kits, respectively. Oxidized glutathione (GSSG) and reduced glutathione (GSH) were measured by colorimetric reaction, and 4-hydroxynenonal (4HNE) by immunohistochemistry. Endoplasmic reticulum stress and dysregulated cellular bioenergetics were determined by western blot analysis. Mitochondrial stress and real-time ATP production rates were determined using a Seahorse Extracellular Flux analyzer. Amelioration of ethanol-induced oxidative/ER stress and mitochondrial energetics was determined using an AMPKα agonist.

RESULTS

Human bronchial epithelial cells treated with ethanol, acetaldehyde, and FAEEs showed a concentration-dependent increase in the secretion of LDH, oxidative/ER stress, deactivation of AMPKα phosphorylation and mitochondrial stress (decreased spare respiratory capacity) with concomitant decreases in mitochondrial and glycolytic ATP production rates. FAEEs caused greater cytotoxicity, ER stress, and dysregulated cellular bioenergetics than those ethanol and its oxidative metabolite. AMPKα agonist-pretreated cells significantly ameliorated ethanol-induced oxidative/ER stress, deactivation of AMPKα, and dysregulated cellular bioenergetics.

CONCLUSIONS

Findings of this study suggest that ethanol and its metabolites contribute to cytotoxicity, oxidative/ER stress, and dysregulation of cellular bioenergetics in hBECs. The attenuation of ethanol-induced ER/oxidative stress and mitochondrial respiration by an AMPKα agonist may reflect a potential for it to be developed as a therapeutic agent for chronic alcohol-associated lung disease.

Prevalence of Alcohol Use Characterized by Phosphatidylethanol in Patients With Respiratory Failure Before and During the COVID-19 Pandemic

BACKGROUND

Alcohol misuse is overlooked frequently in hospitalized patients, but is common among patients with pneumonia and acute hypoxic respiratory failure. Investigations in hospitalized patients rely heavily on self-report surveys or chart abstraction, which lack sensitivity. Therefore, our understanding of the prevalence of alcohol misuse before and during the COVID-19 pandemic is limited.

RESEARCH QUESTION

In critically ill patients with respiratory failure, did the proportion of patients with alcohol misuse, defined by the direct biomarker phosphatidylethanol, vary over a period including the COVID-19 pandemic?

STUDY DESIGN AND METHODS

Patients with acute hypoxic respiratory failure receiving mechanical ventilation were enrolled prospectively from 2015 through 2019 (before the pandemic) and from 2020 through 2022 (during the pandemic). Alcohol use data, including Alcohol Use Disorders Identification Test (AUDIT)-C scores, were collected from electronic health records, and phosphatidylethanol presence was assessed at ICU admission. The relationship between clinical variables and phosphatidylethanol values was examined using multivariable ordinal regression. Dichotomized phosphatidylethanol values (≥ 25 ng/mL) defining alcohol misuse were compared with AUDIT-C scores signifying misuse before and during the pandemic, and correlations between log-transformed phosphatidylethanol levels and AUDIT-C scores were evaluated and compared by era. Multiple imputation by chained equations was used to handle missing phosphatidylethanol data.

RESULTS

Compared with patients enrolled before the pandemic (n = 144), patients in the pandemic cohort (n = 92) included a substantially higher proportion with phosphatidylethanol-defined alcohol misuse (38% vs 90%; P < .001). In adjusted models, absence of diabetes, positive results for COVID-19, and enrollment during the pandemic each were associated with higher phosphatidylethanol values. The correlation between health care worker-recorded AUDIT-C score and phosphatidylethanol level was significantly lower during the pandemic.

INTERPRETATION

The higher prevalence of phosphatidylethanol-defined alcohol misuse during the pandemic suggests that alcohol consumption increased during this period, identifying alcohol misuse as a potential risk factor for severe COVID-19-associated respiratory failure. Results also suggest that AUDIT-C score may be less useful in characterizing alcohol consumption during high clinical capacity.

The pan-liver network theory: From traditional chinese medicine to western medicine

In traditional Chinese medicine (TCM), the liver is the "general organ" that is responsible for governing/maintaining the free flow of qi over the entire body and storing blood. According to the classic five elements theory, zang-xiang theory, yin-yang theory, meridians and collaterals theory, and the five-viscera correlation theory, the liver has essential relationships with many extrahepatic organs or tissues, such as the mother-child relationships between the liver and the heart, and the yin-yang and exterior-interior relationships between the liver and the gallbladder. The influences of the liver to the extrahepatic organs or tissues have been well-established when treating the extrahepatic diseases from the perspective of modulating the liver by using the ancient classic prescriptions of TCM and the acupuncture and moxibustion. In modern medicine, as the largest solid organ in the human body, the liver has the typical functions of filtration and storage of blood; metabolism of carbohydrates, fats, proteins, hormones, and foreign chemicals; formation of bile; storage of vitamins and iron; and formation of coagulation factors. The liver also has essential endocrine function, and acts as an immunological organ due to containing the resident immune cells. In the perspective of modern human anatomy, physiology, and pathophysiology, the liver has the organ interactions with the extrahepatic organs or tissues, for example, the gut, pancreas, adipose, skeletal muscle, heart, lung, kidney, brain, spleen, eyes, skin, bone, and sexual organs, through the circulation (including hemodynamics, redox signals, hepatokines, metabolites, and the translocation of microbiota or its products, such as endotoxins), the neural signals, or other forms of pathogenic factors, under normal or diseases status. The organ interactions centered on the liver not only influence the homeostasis of these indicated organs or tissues, but also contribute to the pathogenesis of cardiometabolic diseases (including obesity, type 2 diabetes mellitus, metabolic [dysfunction]-associated fatty liver diseases, and cardio-cerebrovascular diseases), pulmonary diseases, hyperuricemia and gout, chronic kidney disease, and male and female sexual dysfunction. Therefore, based on TCM and modern medicine, the liver has the bidirectional interaction with the extrahepatic organ or tissue, and this established bidirectional interaction system may further interact with another one or more extrahepatic organs/tissues, thus depicting a complex "pan-hepatic network" model. The pan-hepatic network acts as one of the essential mechanisms of homeostasis and the pathogenesis of diseases.

Chronic alcohol use primes bronchial cells for altered inflammatory response and barrier dysfunction during SARS-CoV-2 infection

Alcohol use disorder (AUD) is a significant public health concern and people with AUD are more likely to develop severe acute respiratory distress syndrome (ARDS) in response to respiratory infections. To examine whether AUD was a risk factor for more severe outcome in response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, we examined early responses to infection using cultured differentiated bronchial epithelial cells derived from brushings obtained from people with AUD or without AUD. RNA-seq analysis of uninfected cells determined that AUD cells were enriched for expression of epidermal genes as compared with non-AUD cells. Bronchial epithelial cells from patients with AUD showed a significant decrease in barrier function 72 h postinfection, as determined by transepithelial electrical resistance. In contrast, barrier function of non-AUD cells was enhanced 72 h after SARS-CoV-2 infection. AUD cells showed claudin-7 that did not colocalize with zonula occludens-1 (ZO-1), indicative of disorganized tight junctions. However, both AUD and non-AUD cells showed decreased β-catenin expression following SARS-CoV-2 infection. To determine the impact of AUD on the inflammatory response to SARS-CoV-2 infection, cytokine secretion was measured by multiplex analysis. SARS-CoV-2-infected AUD bronchial cells had enhanced secretion of multiple proinflammatory cytokines including TNFα, IL-1β, and IFNγ as opposed to non-AUD cells. In contrast, secretion of the barrier-protective cytokines epidermal growth factor (EGF) and granulocyte macrophage-colony stimulating factor (GM-CSF) was enhanced for non-AUD bronchial cells. Taken together, these data support the hypothesis that AUD is a risk factor for COVID-19, where alcohol primes airway epithelial cells for increased inflammation and increased barrier dysfunction and increased inflammation in response to infection by SARS-CoV-2.NEW & NOTEWORTHY Alcohol use disorder (AUD) is a significant risk factor for severe acute respiratory distress syndrome. We found that AUD causes a phenotypic shift in gene expression in human bronchial epithelial cells, enhancing expression of epidermal genes. AUD cells infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) had higher levels of proinflammatory cytokine secretion and barrier dysfunction not present in infected non-AUD cells, consistent with increased early COVID-19 severity due to AUD.

Impact of alcohol consumption on coronavirus disease 2019 severity: A systematic review and meta-analysis

Fear and misinformation lead to widespread myths in the coronavirus disease 2019 (COVID-19) pandemic, such as "consuming high-strength alcohol kills the virus in the inhaled air." However, whether alcohol consumption can affect COVID-19 has not been clarified yet. This study aims to investigate the impact of alcohol consumption on COVID-19 severity. PubMed, Embase, Cochrane Library, Central, CINAHL, ClinicalTrials.gov, and WHO-International Clinical Trials Registry Platform were searched until November 25, 2022. Forty studies (1,697,683 COVID-19 individuals) were analyzed. Brown (patients numbers: 1317, risk ratios [RR] = 1.58, 95% [confidence interval] CI = 1.31 to 1.90, I2  = 0.0%, p < 0.001), American (patients numbers: 3721, RR = 1.51, 95% CI = 1.30 to 1.75, I2  = 0.0%, p < 0.001), and European (patients numbers: 261,437, RR = 2.04, 95% CI = 1.96 to 2.13, I2  = 0.0%, p < 0.001) drinkers were at high risk of severe COVID-19, intensive care unit (ICU) admission, and invasive mechanical ventilation (IMV), respectively. Consistently, individuals with a drinking history were at high risk of severe COVID-19 (patients numbers: 5399, RR = 1.23, 95% CI = 1.02 to 1.48, I2  = 38.4%, p = 0.03) and ICU admission (patients numbers: 6995, RR = 1.32, 95% CI = 1.08 to 1.60, I2  = 46.6%, p = 0.01). In addition, current drinkers had an increased risk of symptomatic COVID-19. However, excessive drinkers were at high risk of COVID-19 hospitalization. Alcohol consumption intensifies COVID-19 severity and deteriorates its clinical outcomes. Here, we strongly propose that people do not drink alcohol during the COVID-19 pandemic.

Impact of Alcohol Misuse on Requirements for Critical Care Services and Development of Hospital Delirium in Patients With COVID-19 pneumonia

Alcohol misuse has been associated with increased morbidity in the setting of pulmonary infections, including the need for critical care resource utilization and development of delirium. How alcohol misuse impacts morbidity and outcomes among patients admitted with COVID-19 pneumonia is not well described. We sought to determine if alcohol misuse was associated with an increased need for critical care resources and development of delirium among patients hospitalized with COVID-19 pneumonia.

DESIGN

Retrospective cohort study.

SETTING

Twelve University of Colorado hospitals between March 2020 and April 2021.

PATIENTS

Adults with a COVID-19 diagnosis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was admission to the ICU. Secondary outcomes included need for mechanical ventilation, development of delirium, and in-hospital mortality. Alcohol misuse was defined by International Classification of Diseases, 10th Revision codes. Of 5,979 patients hospitalized with COVID-19, 26% required ICU admission and 15.4% required mechanical ventilation. Delirium developed in 4.5% and 10.5% died during hospitalization. Alcohol misuse was identified in 4%. In analyses adjusted for age, sex, body mass index, diabetes, and liver disease, alcohol misuse was associated with increased odds of ICU admission (adjusted odds ratio [aOR], 1.46; p < 0.01), mechanical ventilation (aOR, 1.43; p = 0.03), and delirium (aOR, 5.55; p < 0.01) compared with patients without misuse. Mortality rates were not associated with alcohol misuse alone, although the presence of both alcohol misuse and in-hospital delirium significantly increased odds of in-hospital death (aOR, 2.60; p = 0.04).

CONCLUSIONS

Among patients hospitalized with COVID-19, alcohol misuse was associated with increased utilization of critical care resources including ICU admission and mechanical ventilation. Delirium was an important modifiable risk factor associated with worse outcomes in hospitalized patients with alcohol misuse, including increased odds of death.

SARS-CoV-2 Infection and Liver Disease: A Review of Pathogenesis and Outcomes

The impact of the coronavirus disease 2019 (COVID-19) pandemic has been immense, and it continues to have lasting repercussions. While the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus primarily infects the respiratory system, other organ systems are affected, including the liver. Scientific knowledge on the role of SARS-CoV-2 infection and liver injury has evolved rapidly, with recent data suggesting specific hepatotropism of SARS-CoV-2. Moreover, additional concerns have been raised in regard to long-term liver damage, related to emerging cases of post-COVID-19 cholangiopathy and chronic cholestasis. Great effort has also been focused on studying how specific subpopulations with chronic medical conditions might be disproportionately impacted by COVID-19. One such population includes individuals with chronic liver disease (CLD) and cirrhosis, with an expanding body of research indicating these patients being particularly susceptible to adverse outcomes. In this review, we provide an updated summary on the current pathogenesis and mechanism of liver injury in the setting of SARS-CoV-2 infection, the association between health outcomes and SARS-CoV-2 infection in patients with CLD, and the unique consequences of the COVID-19 pandemic on the routine care of patients with CLD.

Alcohol impairs recognition and uptake of Mycobacterium tuberculosis by suppressing toll-like receptor 2 expression

BACKGROUND

Alcohol impairs pulmonary innate immune function and is associated with an increased risk of tuberculosis (TB). Toll-like receptor 2 (TLR2) is a pattern recognition receptor on alveolar macrophages that recognizes Mycobacterium tuberculosis (Mtb). The expression of TLR2 depends, in part, on granulocyte-macrophage colony-stimulating factor (GM-CSF) signaling. Given our prior work demonstrating the suppression of GM-CSF signaling following chronic alcohol ingestion, we hypothesized that alcohol impairs TLR2 expression via the suppression of GM-CSF and thereby reduces the ability of the macrophage to recognize and phagocytose Mtb.

METHODS

Primary alveolar macrophages were isolated from control-fed and alcohol-fed rats. Prior to cell isolation, some alcohol-fed rats were treated with intranasal GM-CSF and then endotracheally inoculated with an attenuated strain of Mtb. Primary macrophages were then isolated and immunofluorescence was used to determine phagocytic efficiency and TLR2 expression in the presence and absence of GM-CSF treatment and phagocytic efficiency in the presence and absence of TLR2 neutralization.

RESULTS

TLR2 expression and phagocytosis of Mtb were significantly lower in the alveolar macrophages of alcohol-fed rats than control-fed rats. In parallel, blocking TLR2 signaling recapitulated this decreased phagocytosis of Mtb. In contrast, intranasal GM-CSF treatment restored TLR2 expression and Mtb phagocytosis in the alveolar macrophages of alcohol-fed rats to levels comparable to those of control-fed rats.

CONCLUSIONS

Chronic alcohol ingestion reduces TLR2 protein expression and phagocytosis of Mtb, likely due to impaired GM-CSF signaling. GM-CSF restores membrane-bound TLR2 expression and phagocytic function.

Alcohol use disorder as a potential risk factor for COVID-19 severity: A narrative review

In Dec. 2019-January 2020, a pneumonia illness originating in Wuhan, China, designated as coronavirus disease 2019 (COVID-19) was shown to be caused by a novel RNA coronavirus designated as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). People with advanced age, male sex, and/or underlying health conditions (obesity, type 2 diabetes, cardiovascular disease, hypertension, chronic kidney disease, and chronic lung disease) are especially vulnerable to severe COVID-19 symptoms and death. These risk factors impact the immune system and are also associated with poor health, chronic illness, and shortened longevity. However, a large percent of patients without these known risk factors also develops severe COVID-19 disease that can result in death. Thus, there must exist risk factors that promote exaggerated inflammatory and immune response to the SARS-CoV-2 virus leading to death. One such risk factor may be alcohol misuse and alcohol use disorder because these can exacerbate viral lung infections like SARS, influenza, and pneumonia. Thus, it is highly plausible that alcohol misuse is a risk factor for either increased infection rate when individuals are exposed to SARS-CoV-2 virus and/or more severe COVID-19 in infected patients. Alcohol use is a well-known risk factor for lung diseases and ARDS in SARS patients. We propose that alcohol has three key pathogenic elements in common with other COVID-19 severity risk factors: namely, inflammatory microbiota dysbiosis, leaky gut, and systemic activation of the NLRP3 inflammasome. We also propose that these three elements represent targets for therapy for severe COVID-19.

Ethanol Consumption Induces Nonspecific Inflammation and Functional Defects in Alveolar Macrophages

Chronic alcohol drinking is associated with increased susceptibility to viral and bacterial respiratory pathogens. In this study, we use a rhesus macaque model of voluntary ethanol self-administration to study the effects of long-term alcohol drinking on the immunological landscape of the lung. We report a heightened inflammatory state in alveolar macrophages (AMs) obtained from ethanol (EtOH)-drinking animals that is accompanied by increased chromatin accessibility in intergenic regions that regulate inflammatory genes and contain binding motifs for transcription factors AP-1, IRF8, and NFKB p-65. In line with these transcriptional and epigenetic changes at the basal state, AMs from EtOH-drinking animals generate elevated inflammatory mediator responses to lipopolysaccharides and respiratory syncytial virus. However, the transcriptional analysis revealed an inefficient induction of interferon-stimulated genes with EtOH in response to the respiratory syncytial virus, suggesting disruption of antimicrobial defenses. Correspondingly, AMs from EtOH-drinking animals exhibited transcriptional shifts indicative of increased oxidative stress and oxidative phosphorylation, which was coupled with higher cytosolic reactive oxygen species and mitochondrial potential. This heightened oxidative stress state was accompanied by decreased ability to phagocytose bacteria. Bulk RNA and assay for transposase-accessible chromatin sequencing data further revealed reduced expression and chromatin accessibility of loci associated with tissue repair and maintenance with chronic EtOH drinking. Similarly, analysis of single-cell RNA sequencing data revealed shifts in cell states from tissue maintenance to inflammatory responses with EtOH. Collectively, these data provide novel insight into mechanisms by which chronic EtOH drinking increases susceptibility to infection in patients with alcohol use disorders.

Alcoholic liver disease: a new insight into the pathogenesis of liver disease

Excessive alcohol consumption contributes to a broad clinical spectrum of liver diseases, from simple steatosis to end-stage hepatocellular carcinoma. The liver is the primary organ that metabolizes ingested alcohol and is exquisitely sensitive to alcohol intake. Alcohol metabolism is classified into two pathways: oxidative and non-oxidative alcohol metabolism. Both oxidative and non-oxidative alcohol metabolisms and their metabolites have toxic consequences for multiple organs, including the liver, adipose tissue, intestine, and pancreas. Although many studies have focused on the effects of oxidative alcohol metabolites on liver damage, the importance of non-oxidative alcohol metabolites in cellular damage has also been discovered. Furthermore, extrahepatic alcohol effects are crucial for providing additional information necessary for the progression of alcoholic liver disease. Therefore, studying the effects of alcohol-producing metabolites and interorgan crosstalk between the liver and peripheral organs that express ethanol-metabolizing enzymes will facilitate a comprehensive understanding of the pathogenesis of alcoholic liver disease. This review focuses on alcohol-metabolite-associated hepatotoxicity due to oxidative and non-oxidative alcohol metabolites and the role of interorgan crosstalk in alcoholic liver disease pathogenesis.

Analysis of Patients with Alcohol Dependence Treated in Silesian Intensive Care Units

Analysis of patients with alcohol dependence (AD) treated in intensive care units has never been performed in Poland. Data from 25,416 adult patients identified in a Silesian Registry of Intensive Care Units were analysed. Patients with AD were identified, and their data were compared with the remaining population. Preadmission and admission variables that independently influenced ICU death in these patients were identified. Among 25,416 analysed patients, 2285 subjects (9.0%) were indicated to have AD among their comorbidities. Patients with AD were significantly younger (mean age: 53.3 ± 11.9 vs. 62.2 ± 15.5 years, p < 0.001) but had a higher mean APACHE II score at admission and were more frequently admitted to the ICU due to trauma, poisonings, acute pancreatitis, and severe metabolic abnormalities. ICU death and unfavourable outcomes were more frequent in these patients (47.8% vs. 43.0%, p < 0.001 and 54.1% vs. 47.0%, p < 0.001, respectively). Multiorgan failure as the primary cause of ICU admission was among the most prominent independent risk factors for ICU death in these patients (OR: 3.30, p < 0.001). Despite the younger age, ICU treatment of patients with AD was associated with higher mortality and a higher percentage of unfavourable outcomes.

Acute Respiratory Distress Syndrome and COVID-19: A Literature Review

Acute respiratory distress syndrome (ARDS) is an overwhelming inflammatory disorder of the lung due to direct and indirect insults to the lungs. ARDS is characterized by increased vascular permeability, protein-rich edema, diffuse alveolar infiltrate, and loss of aerated lung tissue, leading to decreased lung compliance, tachypnea, and severe hypoxemia. COVID-19 is generally associated with ARDS, and it has gained prime importance since it started. The mortality rate is alarmingly high in COVID-19-related ARDS patients regardless of advances in mechanical ventilation. Several pharmacological agents, including corticosteroids, nitric oxide, neuromuscular blocker, anti-TNF, statins, and exogenous surfactant, have been studied and some are under investigation, like ketoconazole, lisofylline, N-acetylcysteine, prostaglandins, prostacyclin, and fish oil. The purpose of this review is to appraise the understanding of the pathophysiology of ARDS, biomarkers, and clinical trials of pharmacological therapies of ARDS and COVID-19-related ARDS.

Combined and interactive effects of alcohol drinking and cigarette smoking on the risk of severe illness and poor clinical outcomes in patients with COVID-19: A multicentre retrospective cohort study

Objectives

Cigarette smoking is an established risk factor for illness severity and adverse outcomes in patients with COVID-19. Alcohol drinking may also be a potential risk factor for disease severity. However, the combined and interactive effects of drinking and smoking on COVID-19 have not yet been reported. This study aimed to examine the combined and interactive effects of alcohol drinking and cigarette smoking on the risk of severe illness and poor outcomes in patients with COVID-19.

Study design

This was a multicentre retrospective cohort study.

Methods

This study retrospectively reviewed the data of 1399 consecutive hospitalised COVID-19 patients from 43 designated hospitals. Patients were grouped according to different combinations of drinking and smoking status. Multivariate mixed-effects logistic regression models were used to estimate the combined and interactive effects of drinking and smoking on the risk of severe COVID-19 and poor clinical outcomes.

Results

In the study population, 7.3% were drinkers/smokers, 4.3% were drinkers/non-smokers and 4.9% were non-drinkers/smokers. After controlling for potential confounders, smokers or drinkers alone did not show a significant increase in the risk of severe COVID-19 or poor clinical outcomes compared with non-drinkers/non-smokers. Moreover, this study did not observe any interactive effects of drinking and smoking on COVID-19. Drinkers/smokers had a 62% increased risk (odds ratio = 1.62, 95% confidence interval: 1.01-2.60) of severe COVID-19 but did not have a significant increase in the risk for poor clinical outcomes compared with non-drinkers/non-smokers.

Conclusions

Combined exposure to drinking and smoking increases the risk of severe COVID-19, but no direct effects of drinking or smoking, or interaction effects of drinking and smoking, were detected.

Transcriptional and Epigenetic Regulation of Monocyte and Macrophage Dysfunction by Chronic Alcohol Consumption

Drinking alcohol, even in moderation, can affect the immune system. Studies have shown disproportionate effects of alcohol on circulating and tissue-resident myeloid cells (granulocytes, monocytes, macrophages, dendritic cells). These cells orchestrate the body's first line of defense against microbial challenges as well as maintain tissue homeostasis and repair. Alcohol's effects on these cells are dependent on exposure pattern, with acute drinking dampening but chronic drinking enhancing production of inflammatory mediators. Although chronic drinking is associated with heightened systemic inflammation, studies on tissue resident macrophage populations in several organs including the spleen, liver, brain, and lung have also shown compromised functional and metabolic capacities of these cells. Many of these effects are thought to be mediated by oxidative stress caused by alcohol and its metabolites which can directly impact the cellular epigenetic landscapes. In addition, since myeloid cells are relatively short-lived in circulation and are under constant repopulation from the bone marrow compartment, alcohol's effects on bone marrow progenitors and hematopoiesis are important for understanding the impact of alcohol systemically on these myeloid populations. Alcohol-induced disruption of progenitor, circulating, and tissue resident myeloid populations contribute to the increased susceptibility of patients with alcohol use disorders to viral and bacterial infections. In this review, we provide an overview of the impact of chronic alcohol consumption on the function of monocytes and macrophages in host defense, tissue repair and inflammation. We then summarize our current understanding of the mechanisms underlying alcohol-induced disruption and examine changes in transcriptome and epigenome of monocytes and mcrophages. Overall, chronic alcohol consumption leads to hyper-inflammation concomitant with decreased microbial and wound healing responses by monocytes/macrophages due to a rewiring of the epigentic and transcriptional landscape. However, in advanced alcoholic liver disease, myeloid cells become immunosuppressed as a response to the surrounding hyper-inflammatory milieu. Therefore, the effect of chronic alcohol on the inflammatory response depends on disease state and the immune cell population.

Donor factors and risk of primary graft dysfunction and mortality post lung transplantation: A proposed conceptual framework

Lung transplantation remains a therapeutic option in end-stage lung disease. However, despite advances in the field, early allograft function can be compromised by the development of primary graft dysfunction (PGD); this being the leading cause of morbidity and mortality immediately following the lung transplant procedure. Several recipient factors have been associated with increased risk of PGD, but less is known about donor factors. Aging, tobacco, and chronic alcohol use are donor factors implicated, but how these factors promote PGD remains unclear. Herein, we discuss the available clinical data that link these donor factors with outcomes after lung transplantation, and how they might render the recipient susceptible to PGD through a two-hit process.

Current View on the Mechanisms of Alcohol-Mediated Toxicity

Alcohol is a psychoactive substance that is widely used and, unfortunately, often abused. In addition to acute effects such as intoxication, it may cause many chronic pathological conditions. Some of the effects are very well described and explained, but there are still gaps in the explanation of empirically co-founded dysfunction in many alcohol-related conditions. This work focuses on reviewing actual knowledge about the toxic effects of ethanol and its degradation products.

Alcohol-Associated Liver Disease Before and After COVID-19-An Overview and Call for Ongoing Investigation

The Coronavirus Disease 2019 (COVID-19) pandemic has exacted a heavy toll on patients with alcohol-associated liver disease (ALD) and alcohol use disorder (AUD). The collective burden of ALD and AUD was large and growing, even before the COVID-19 pandemic. There is accumulating evidence that this pandemic has had a large direct effect on these patients and is likely to produce indirect effects through delays in care, psychological strain, and increased alcohol use. Now a year into the pandemic, it is important that clinicians fully understand the effects of the COVID-19 pandemic on patients with ALD and AUD. To fill existing gaps in knowledge, the scientific community must set research priorities for patients with ALD regarding their risk of COVID-19, prevention/treatment of COVID-19, changes in alcohol use during the pandemic, best use of AUD treatments in the COVID-19 era, and downstream effects of this pandemic on ALD. Conclusion: The COVID-19 pandemic has already inflicted disproportionate harms on patients with ALD, and ongoing, focused research efforts will be critical to better understand the direct and collateral effects of this pandemic on ALD.

Pretransplant Risk Factors Can Predict Development of Acute Respiratory Distress Syndrome after Hematopoietic Stem Cell Transplantation

Rationale: Acute respiratory distress syndrome (ARDS) is a common complication after hematopoietic stem cell transplantation (HCT) and is a major contributor to nonrelapse mortality. Objectives: To better understand pretransplant risk factors for developing ARDS after HCT. Methods: This is a single-center observational study comparing risk factors for ARDS development in 164 patients who went on to develop post-HCT ARDS compared with 492 patients who did not. The patients were matched 1 to 3 on age, sex, type of transplant (allogeneic vs. autologous), and underlying disease. Pertinent risk factors were analyzed separately in multivariable conditional logistic regression after adjustment for a priori variables known to be associated with ARDS development. Results: Patients with ARDS were more likely to have a lower pretransplant pulmonary function as measured by forced vital capacity (FVC) (odds ratio [OR], 0.54 [0.42-0.70] per liter increase in FVC; P < 0.001), forced expiratory volume in one second (FEV₁) (OR, 0.52 [0.38-0.71] per liter increase in FEV₁; P < 0.001) and diffusing capacity (OR, 0.92 [0.88-0.96] per ml/min/mm Hg increase in diffusing capacity; P < 0.001). Several laboratory indices were predictive of subsequent ARDS development including elevated AST (aspartate aminotransferase) (OR, 1.01 [1.00-1.01]; P < 0.008), lower serum albumin (OR, 0.44 [0.30-0.66]; P < 0.001), lower pretransplant hemoglobin (OR, 0.82 [0.73-0.92]; P = 0.001), and lower leukocyte count (OR, 0.88 [0.79-0.99]; P < 0.03). Patients who went on to develop ARDS were more likely to have been hospitalized in the year before the transplant (OR, 1.11 [1.04-1.20]; P = 0.003), and required invasive or noninvasive ventilation during that hospitalization. Lastly, patients with ARDS were significantly more likely to have received carboplatin, thalidomide, methotrexate, and cisplatin than the non-ARDS control subjects. Conclusions: Several risk factors for developing ARDS after HCT are identifiable at the time of transplantation, well before the development of critical illness and ARDS. The identification of risk factors long before ARDS develops is relatively unique to the HCT population. Further work is needed to develop usable risk prediction tools in this setting.

Asymmetric distribution of dynamin-2 and β-catenin relative to tight junction spikes in alveolar epithelial cells

Tight junctions between lung alveolar epithelial cells maintain an air-liquid barrier necessary for healthy lung function. Previously, we found that rearrangement of tight junctions from a linear, cortical orientation into perpendicular protrusions (tight junction spikes) is associated with a decrease in alveolar barrier function, especially in alcoholic lung syndrome. Using quantitative super-resolution microscopy, we found that spikes in control cells were enriched for claudin-18 as compared with alcohol-exposed cells. Moreover, using an in situ method to measure barrier function, tight junction spikes were not associated with localized increases in permeability. This suggests that tight junction spikes have a regulatory role as opposed to causing a physical weakening of the epithelial barrier. We found that tight junction spikes form at cell-cell junctions oriented away from pools of β-catenin associated with actin filaments, suggesting that adherens junctions determine the directionality of tight junction spikes. Dynamin-2 was associated with junctional claudin-18 and ZO-1, but showed little localization with β-catenin and tight junction spikes. Treatment with Dynasore decreased the number of tight junction spikes/cell, increased tight junction spike length, and stimulated actin to redistribute to cortical tight junctions. By contrast, Dynole 34-2 and MiTMAB altered β-catenin localization, and reduced tight junction spike length. These data suggest a novel role for dynamin-2 in tight junction spike formation by reorienting junction-associated actin. Moreover, the greater spatial separation of adherens and tight junctions in squamous alveolar epithelial cells as compared with columnar epithelial cells facilitates analysis of molecular regulation of the apical junctional complex.

COVID-19-Related Neuropsychiatric Symptoms in Patients With Alcohol Abuse Conditions During the SARS-CoV-2 Pandemic: A Retrospective Cohort Study Using Real World Data From Electronic Health Records of a Tertiary Hospital

Patients with an alcohol abuse disorder exhibit several medical characteristics and social determinants, which suggest a greater vulnerability to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and a worse course of the coronavirus disease 2019 (COVID-19) once infected. During the first wave of the COVID-19, most of the countries have register an increase in alcohol consumption. However, studies on the impact of alcohol addiction on the risk of COVID-19 infection are very scarce and inconclusive. This research offers a descriptive observational retrospective cohort study using real world data obtained from the Electronic Health Records. We found that patients with a personal history of alcohol abuse were 8% more likely to extend their hospitalization length of stay for 1 day (95% CI = 1.04–1.12) and 15% more likely to extend their Intensive Care Unit (ICU) length of stay (95% CI = 1.01–1.30). They were also 5.47 times more at risk of needing an ICU admission (95% CI = 1.61–18.57) and 3.54 times (95% CI = 1.51–8.30) more at risk of needing a respirator. Regarding COVID-19 symptoms, patients with a personal history of alcohol abuse were 91% more likely of exhibiting dyspnea (95% CI = 1.03–3.55) and 3.15 times more at risk of showing at least one neuropsychiatric symptom (95% CI = 1.61–6.17). In addition, they showed statistically significant differences in the number of neuropsychiatric symptoms developed during the COVID-19 infection. Therefore, we strongly recommend to warn of the negative consequences of alcohol abuse over COVID-19 complications. For this purpose. Clinicians should systematically assess history of alcohol issues and drinking habits in all patients, especially for those who seek medical advice regarding COVID-19 infection, in order to predict its severity of symptoms and potential complications. Moreover, this information should be included, in a structured field, into the Electronic Health Record to facilitate the automatic extraction of data, in real time, useful to evaluate the decision-making process in a dynamic context.

The important role of immunization in alcoholic and non-alcoholic chronic liver disease: A population-based study

OBJECTIVE

To determine differences in frequencies of vaccine-preventable diseases between alcoholic liver disease (ALD) and non-alcoholic liver disease (NALD) patients.

METHODS

This population-based cohort study used USA national inpatient sample ICD-9 codes from January 2012 to September 2015. Frequencies of admissions for ALD and NALD in patients with pneumococcal pneumonia, influenza, herpes zoster virus, varicella zoster virus, hepatitis A, hepatitis B, human papilloma virus, meningococcal meningitis, diphtheria, pertussis and tetanus were measured. Frequencies and patients' characteristics were compared for ALD and NALD using χ² test and multivariate logistic regression analysis.

RESULTS

There was no difference in admissions for hepatitis A and pneumococcal pneumonia between the ALD and NALD groups. There were fewer admissions for hepatitis B (1.17% vs 1.80%, odds ratio [OR] 0.64, P < 0.01), herpes zoster (0.12% vs 0.17%, OR 0.69, P < 0.01), influenza (0.16% vs 0.26%, OR 0.59, P < 0.01) and all others (0.005% vs 0.015%, OR 0.36, P = 0.01) in the ALD group than the NALD group. The extreme all patient refined-diagnosis related groups mortality risk was 15.24% in ALD and 7.77% in NALD admissions (P < 0.0001).

CONCLUSIONS

The most frequent vaccine-preventable disease in both groups was hepatitis B. Patients with NALD had higher odds of admissions for hepatitis B, herpes zoster virus, influenza and other vaccine-preventable disease than ALD patients. However, the ALD group had a higher risk of mortality when admitted to hospital with a vaccine-preventable disease than the NALD group.

Liver-lung axes in alcohol-related liver disease

Alcohol-related liver disease (ALD) and alcohol-related susceptibility to acute lung injury are the leading causes of morbidity and mortality due to chronic alcohol abuse. Most commonly, alcohol-induced injury to both organs are evaluated independently, although they share many parallel mechanisms of injury. Moreover, recent studies indicate that there is a potential liver lung axis that may contribute to organ pathology. This mini-review explores established and potential mechanisms of organ-organ crosstalk in ALD and alcohol-related lung injury.

[Acute respiratory distress syndrome]

Das „acute respiratory distress syndrome“ (ARDS) ist ein intensivmedizinisches Syndrom, das bei gleichbleibend erhöhter Prävalenz weiterhin eine hohe Mortalität und Morbidität bedingt. Seit der initialen Beschreibung im Jahr 1968 sind inzwischen die Pathophysiologie mit Inflammation nach potenziellen Triggern, die Diagnostik zugrunde liegender Krankheitsentitäten, die Wertigkeit von differenzierter invasiver Beatmung und intensivmedizinischen Prozeduren und die Prognose deutlich besser erforscht und verstanden. Die Berliner ARDS-Definition aus dem Jahr 2012 mit dem Ziel der bettseitigen Identifikation von Patienten mit ARDS trägt diesen Tatsachen Rechnung. Vermeidung von invasiver Beatmung, wenn möglich, lungenprotektive Beatmung, wenn invasive Beatmung notwendig ist mit adäquatem PEEP (positiver endexspiratorischer Druck), und Reduktion von Baro- und Atelektrauma sowie Volumenmanagement und Lagerungstherapie bleiben die wichtigsten apparativen Therapien. Kausale Therapien sind weiterhin, abgesehen von der Behandlung zugrunde liegender Infektionen, nicht vorhanden. Für die Überlebenden eines ARDS ergeben sich sehr häufig relevante Langzeitfolgen.

Heavy Drinking Habits Are Associated with Worse In-Hospital Outcomes in Patients with Acute Coronary Syndrome: An Insight from the AMIS Plus Registry

BACKGROUND

The association between alcohol consumption and the occurrence of coronary heart disease is well described in the literature, while data regarding the impact of regular alcohol consumption on in-hospital outcomes in the setting of acute coronary syndrome (ACS) are lacking. We aimed to evaluate the impact of self-reported alcohol consumption on in-hospital outcomes in patients with ACS.

METHODS

Data derived from patients enrolled between 2007 and 2019 in the Acute Myocardial Infarction in Switzerland (AMIS) Plus registry were retrospectively analyzed. Patients were stratified based on alcohol drinking pattern. Primary outcome was all-cause in-hospital mortality, while secondary outcomes were set as incidence of major adverse cardiac and cerebrovascular events (MACCEs). Outcome comparisons according to quantity of daily alcohol intake were also performed.

RESULTS

Records concerning alcohol consumption were available in 25,707 patients; 5,298 of them (21%) fulfilled the criteria of regular alcohol consumption. Regular drinkers were predominantly male, younger, smokers, more comorbid and with a worse clinical presentation as compared with abstainers/occasional drinkers. Daily alcohol intake was reported in 4,059 (77%) of these patients (regular drinkers). Among them, 2,640 were light drinkers (≤2 drinks/day) and 1,419 heavy drinkers (>2 drinks/day). In-hospital mortality and MACCEs of heavy drinkers were significantly higher compared with those of light drinkers (5.4 vs. 3.3% and 7.0 vs. 4.4%, both p = 0.001). When tested together with Global Registry of Acute Coronary Events risk score parameters, heavy alcohol consumption was independently associated with in-hospital mortality (p = 0.004).

CONCLUSIONS

Our results support that heavy alcohol consumption is an independent predictor of in-hospital mortality in patients presenting with ACS.

The acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS) is a prevalent cause of acute respiratory failure with high rates of mortality, as well as short- and long-term complications, such as physical and cognitive impairment. Therefore, early recognition of this syndrome and application of well-demonstrated therapeutic interventions are essential to change the natural course of this entity and bring about positive clinical outcomes. In this article, we review updated concepts in ARDS. Specifically, we discuss the current definition of ARDS, its risk factors, and the evidence supporting ventilation management, adjunctive therapies, and interventions required in refractory hypoxemia.

Challenges to improving patient outcome following massive transfusion in severe trauma

Introduction: Uncontrolled hemorrhage with trauma-induced coagulopathy (TIC) still represents the most common cause of preventable death after trauma. Timely diagnosis and treatment including bleeding control and hemostatic resuscitation to correct TIC are important, as death from exsanguination occurs rapidly. Recognizing who requires an early massive transfusion together with the initiation of corresponding massive transfusion protocols (MTPs) is key to outcome.Areas covered: This expert review summarizes the current state of MT including the activation and termination of MTPs, complications of MT, and strategies for refinement in the administration of blood products in order to avoid harmful over-transfusion.Expert opinion: MTPs should be initiated and continued until normal physiologic parameters are reached and definitive control of bleeding is achieved. Hospitals should develop their own MTPs, guided by evidence, and according to local infrastructure, logistics, needs and patient populations. Massive transfusion, defined as > 10 units of packed red blood cell concentrates (pRBCs) within the first 24 hours of hospital admission, can be life-saving, but is not without complications. MTPs are currently being refined through targeted and early goal-directed approaches which include functional coagulation testing assays to better guide the administration of blood products and hemostatic agents once the patient is stabilized.

RNAi therapeutic strategies for acute respiratory distress syndrome

Acute respiratory distress syndrome (ARDS), replacing the clinical term acute lung injury, involves serious pathophysiological lung changes that arise from a variety of pulmonary and nonpulmonary injuries and currently has no pharmacological therapeutics. RNA interference (RNAi) has the potential to generate therapeutic effects that would increase patient survival rates from this condition. It is the purpose of this review to discuss potential targets in treating ARDS with RNAi strategies, as well as to outline the challenges of oligonucleotide delivery to the lung and tactics to circumvent these delivery barriers.

Alcohol-dependent pulmonary inflammation: A role for HMGB-1

Previous studies have demonstrated that acute alcohol intoxication significantly impairs lung immune responses, which can lead to the tissue being undefended from microbial infection and resulting disease. Data suggest that acute intoxication presents an axis where simultaneously suppressing early pro-inflammatory cytokines while inducing anti-inflammatory signals contributes to alcohol-dependent immune suppression in the lung, and thus undeterred microbial replication. Interestingly, alcoholics and those with alcohol use disorder present with increased pneumonia and acute respiratory diseases (ARDs), suggesting a more active priming of inflammatory responses in the lungs. There is current research evaluating the acute effects of binge ethanol consumption on adolescents, which is of grave concern, though long-term effects of adolescent ethanol binge exposure are less studied. We hypothesize that adolescent binge drinking may prime the individual to severe pulmonary distress, when later challenged by a microbial pathogen. Herein, we evaluate a model of adolescent intermittent ethanol (AIE) exposure to investigate pulmonary pathology after microbial challenge. Ethanol was administered to adolescent mice using a binge exposure schedule, and mice were then rested to early adulthood. These mice were then challenged with a sub-lethal intranasal inoculation of Klebsiella pneumoniae and evaluated for severity of disease. We find that AIE exposure initially activates inflammatory mediators within the lung, which resolves over time. However, when challenged with a microbial pathogen after this resolution period, these animals present with more severity of inflammation, pulmonary tissue damage, and mortality when challenged with a pulmonary microbial infection. Interestingly, our data suggest a role for alcohol-dependent release of the protein HMGB-1 from host cells, for both morbidity and mortality in our model of microbial-dependent pulmonary inflammation.

Chronic + binge alcohol exposure promotes inflammation and alters airway mechanics in the lung

INTRODUCTION

Alcohol use disorders are major risk factors for the development of and susceptibility to acute respiratory distress syndrome. Although these risks of alcohol consumption on the lung are well described, mechanisms by which alcohol abuse promotes acute lung injury are poorly understood. These gaps in our understanding are due, at least in part, to limitations of animal models to recapitulate human alcohol consumption. Recently, a new model of chronic plus binge alcohol exposure was developed that is hypothesized to better model drinking patterns of individuals with alcohol use disorders. Specifically, this paradigm models chronic consumption coupled with periodic bouts of heavy drinking. The impacts of this alcohol-exposure regimen on the lung are uncharacterized. Therefore, the goal of this study was to examine lung injury and inflammation in a well-characterized experimental model of chronic + binge alcohol exposure.

METHODS

10-week-old male C57Bl6/J mice were administered ethanol-containing (or isocaloric control) liquid diet for 10 days, followed by a single ethanol gavage (5 g/kg). Lung inflammation and pulmonary function were assessed.

RESULTS

Ten days of ethanol-containing liquid diet alone (chronic) did not detectably affect any variables measured. However, ethanol diet plus gavage (chronic + binge) caused neutrophils to accumulate in the lung tissue and in the bronchoalveolar lavage fluid 24 h post-binge. This inflammatory cell recruitment was associated with airway hyper-responsiveness to inhaled methacholine, as indicated by elevated resistance, Newtonian resistance, and respiratory resistance.

CONCLUSIONS

Taken together, the novel findings reveal that ethanol alone, absent of any secondary inflammatory insult, is sufficient to produce inflammation in the lung. Although these changes were relatively mild, they were associated with functional changes in the central airways. This animal model may be useful in the future for identifying mechanisms by which alcohol abuse sensitizes at-risk individuals to lung injury.

Self-reported alcohol use in the cystic fibrosis community

INTRODUCTION

Excessive alcohol use (EAU), a harmful pattern of drinking that includes binge drinking and heavy use, occurs in 25% (binge) and 6% (heavy use) of the US population, respectively. Little is known about alcohol use in individuals with cystic fibrosis (CF). The objective of this investigation is to examine alcohol consumption patterns in individuals with CF using a health survey administered from a social media platform.

METHODS

Individuals with CF, 18 years of age or older, were recruited for participation through social media and internet-based platforms.

RESULTS

1135 individuals initially participated in the survey and 84% (n = 952) were eligible and completed the survey. Of the respondents, 77% (n = 729) currently consume alcohol, 18% (n = 171) formerly consumed alcohol, and 5% (n = 52) never consumed alcohol. Amongst the people with CF who currently consume alcohol, 54% (N = 391) met criteria for EAU. Thirty percent of current drinkers experienced symptoms of harmful alcohol use. Of those who met criteria for EAU, 7% wore oxygen, 6% had a lung transplant, 10% had liver disease and 32% had diabetes. Those with EAU reported more hospitalizations than those without EAU [244 (62%) vs 182 (54%), p = .034]. Characteristics associated with EAU after multivariable adjustment included younger age, unmarried status, male gender and younger age at initiation of drinking.

CONCLUSION

EAU is occurring at a much higher proportion in individuals with CF. A substantial percentage of CF individuals with EAU also have medical co-morbidities. Screening, brief intervention, and referral to treatment for EAU in CF clinics is warranted.

Effects of drug abuse, smoking and alcohol on donor hearts and lungs

Potential heart and lung donors with a history of illicit drugs and/or smoking and alcohol are frequently offered, though there is no clear guidance on when it is safe to use these organs. A review of the literature on effects of drugs, alcohol and smoking on donor outcomes, and the effects of these on the intact heart and lung was undertaken. There has been a marked increase in deaths from opioid abuse in many developed countries, though recent evidence suggests that outcomes after cardiothoracic transplantation are equivalent to nonopioid donor causes of death. For donor smoking, there is an increased risk with lung transplantation; however, that risk is less when compared to further waiting on the transplant list for a nonsmoking alternative. Heavy alcohol consumption does not adversely affect heart transplantation, and there is no clear evidence of adverse outcomes after lung transplantation. There are no overall effects of cannabis or cocaine on survival after heart or lung transplantation. In all these cases, careful donor assessment can establish if a particular organ can be used. In most cases, use of drugs requires careful assessment, but is not in of itself a contraindication to cardiothoracic transplantation.

Nonpulmonary risk factors of acute respiratory distress syndrome in patients with septic bacteraemia

BACKGROUND/AIMS

The relationship between nonpulmonary organ failure and the development of acute respiratory distress syndrome (ARDS) in patients with sepsis has not been well studied.

METHODS

We retrospectively reviewed the medical records of patients with septic bacteremia admitted to the medical intensive care unit (ICU) of a tertiary academic hospital between January 2013 and December 2016.

RESULTS

The study enrolled 125 patients of median age 73.0 years. Urinary (n = 47), hepatobiliary (n = 30), and pulmonary infections (n = 28) were the most common causes of sepsis; the incidence of ARDS was 17.6%. The total number of nonpulmonary organ failures at the time of ICU admission was higher in patients with ARDS than in those without (p = 0.011), and the cardiovascular, central nervous system (CNS), and coagulation scores were significantly higher in ARDS patients. On multivariate analysis, apart from pneumonia sepsis, the CNS (odds ratio [OR], 1.917; 95% confidence interval [CI], 1.097 to 3.348) and coagulation scores (OR, 2.669; 95% CI, 1.438 to 4.954) were significantly associated with ARDS development. The 28-day and in-hospital mortality rates were higher in those with ARDS than in those without (63.6 vs. 8.7%, p < 0.001; 72.7% vs. 11.7%, p < 0.001), and ARDS development was found to be an independent risk factor for 28-day mortality.

CONCLUSION

Apart from pneumonia, CNS dysfunction and coagulopathy were significantly associated with ARDS development, which was an independent risk factor for 28-day mortality.

Acute respiratory distress syndrome

The acute respiratory distress syndrome (ARDS) is a common cause of respiratory failure in critically ill patients and is defined by the acute onset of noncardiogenic pulmonary oedema, hypoxaemia and the need for mechanical ventilation. ARDS occurs most often in the setting of pneumonia, sepsis, aspiration of gastric contents or severe trauma and is present in ~10% of all patients in intensive care units worldwide. Despite some improvements, mortality remains high at 30-40% in most studies. Pathological specimens from patients with ARDS frequently reveal diffuse alveolar damage, and laboratory studies have demonstrated both alveolar epithelial and lung endothelial injury, resulting in accumulation of protein-rich inflammatory oedematous fluid in the alveolar space. Diagnosis is based on consensus syndromic criteria, with modifications for under-resourced settings and in paediatric patients. Treatment focuses on lung-protective ventilation; no specific pharmacotherapies have been identified. Long-term outcomes of patients with ARDS are increasingly recognized as important research targets, as many patients survive ARDS only to have ongoing functional and/or psychological sequelae. Future directions include efforts to facilitate earlier recognition of ARDS, identifying responsive subsets of patients and ongoing efforts to understand fundamental mechanisms of lung injury to design specific treatments.

The Effect of Alcohol Consumption on the Risk of ARDS: A Systematic Review and Meta-Analysis

BACKGROUND

To conduct a systematic review and meta-analysis evaluating the association between alcohol consumption and the risk of ARDS in adults.

METHODS

Medline, EMBASE and Web of Science were searched to identify observational studies evaluating the association between prior alcohol intake and the occurrence of ARDS among adults, published between 1985 and 2015 and with no language restriction. Reference lists were also screened. Demographic baseline data were extracted independently by two reviewers and random-effects meta-analyses were used to estimate pooled effect sizes with 95% confidence intervals. Subgroup analyses were used to explore heterogeneity.

RESULTS

Seventeen observational studies (177,674 people) met the inclusion criteria. Meta-analysis of 13 studies showed that any measure of high relative to low alcohol consumption was associated with a significantly increased risk of ARDS (OR, 1.89; 95% CI, 1.45-2.48; I2 = 48%; 13 studies); no evidence of publication bias was seen (P = .150). Sensitivity analyses indicated that this association was attributable primarily to an effect of a history of alcohol abuse (OR, 1.90; 95% CI, 1.40-2.60; 10 studies). Also, subgroup analyses identified that heterogeneity was explained by predisposing condition (trauma, sepsis/septic shock, pneumonia; P = .003).

CONCLUSIONS

Chronic high alcohol consumption significantly increases the risk of ARDS. This finding suggests that patients admitted to hospital should be screened for chronic alcohol use.

Implementation of an ICU-Specific Alcohol Withdrawal Syndrome Management Protocol Reduces the Need for Mechanical Ventilation

STUDY OBJECTIVE

Alcohol use disorders are prevalent and put patients at risk for developing alcohol withdrawal syndrome (AWS). Treatment of AWS with a symptom-triggered protocol standardizes management and may avoid AWS-related complications. The objective of this study was to evaluate whether implementation of a specific intensive care unit (ICU) symptom-triggered protocol for the management of AWS was associated with improved clinical outcomes and, in particular, would reduce the risk of patients with AWS requiring mechanical ventilation.

DESIGN

Retrospective pre- and postprotocol implementation study.

SETTING

A 36-bed closed medical ICU (MICU) at a large tertiary care teaching hospital in an urban setting.

PATIENTS

A total of 233 adults admitted to the MICU with any diagnosis of alcohol use disorders based on International Classification of Diseases, Ninth Revision codes and who received at least one dose of any benzodiazepine; of these patients, 139 were in the preprotocol era (August 2009-January 2010 and August 2010-January 2011), and 94 were in the postprotocol era (August 2012-January 2013) after implementation of the Yale Alcohol Withdrawal Protocol (YAWP) in April 2012.

MEASUREMENTS AND MAIN RESULTS

The YAWP pairs a modified Minnesota Detoxification Scale with an order set that includes benzodiazepine dosing regimens and suggests adjuvant therapies. AWS was the primary reason for ICU admission (107/233 patients [45.9%]) and did not significantly vary between study eras (p=0.2). Of the 233 patients included, 81.1% were male and 67.0% were white, which did not significantly differ by study era. Severity of illness at MICU admission did not significantly differ between patients in the preprotocol and postprotocol eras (Acute Physiology and Chronic Health Evaluation [APACHE] II median scores of 12 [interquartile range (IQR) 9-17] and 12.5 [IQR 7-16], respectively, p=0.4). Median lorazepam-equivalent dose per MICU day, duration of benzodiazepine infusion, and use of adjuvant therapy were not significantly different between eras. MICU intubation was less common in the postprotocol era (36/139 patients [25.9%] preprotocol vs 8/94 patients [8.5%] postprotocol, p=0.0009). ICU-related pneumonia was also decreased in the postprotocol era (30/139 patients [21.6%] preprotocol vs 10/94 patients [10.6%] postprotocol, p=0.03). After adjusting for demographics, adjuvant therapies, and APACHE II scores, protocol implementation was associated with a decreased odds of MICU intubation (odds ratio 0.13, 95% confidence interval 0.04-0.39).

CONCLUSION

Implementation of YAWP was associated with a decreased risk of MICU intubation in patients at risk for AWS.

Endothelial biomarkers in human sepsis: pathogenesis and prognosis for ARDS

Experimental models of sepsis in small and large animals and a variety of in vitro preparations have established several basic mechanisms that drive endothelial injury. This review is focused on what can be learned from the results of clinical studies of plasma biomarkers of endothelial injury and inflammation in patients with sepsis. There is excellent evidence that elevated plasma levels of several biomarkers of endothelial injury, including von Willebrand factor antigen (VWF), angiopoietin-2 (Ang-2), and soluble fms-like tyrosine kinase 1 (sFLT-1), and biomarkers of inflammation, especially interleukin-8 (IL-8) and soluble tumor necrosis factor receptor (sTNFr), identify sepsis patients with a higher mortality. There are also some data that elevated levels of endothelial biomarkers can identify which patients with non-pulmonary sepsis will develop acute respiratory distress syndrome (ARDS). If ARDS patients are divided among those with indirect versus direct lung injury, then there is an association of elevated levels of endothelial biomarkers in indirect injury and markers of inflammation and alveolar epithelial injury in patients with direct lung injury. New research suggests that the combination of biologic and clinical markers may make it possible to segregate patients with ARDS into hypo- versus hyper-inflammatory phenotypes that may have implications for therapeutic responses to fluid therapy. Taken together, the studies reviewed here support a primary role of the microcirculation in the pathogenesis and prognosis of ARDS after sepsis. Biological differences identified by molecular patterns could explain heterogeneity of treatment effects that are not explained by clinical factors alone.

Alcohol abuse is associated with enhanced pulmonary and systemic xanthine oxidoreductase activity

Acute respiratory distress syndrome (ARDS) is a common and devastating disorder. Alcohol use disorders (AUDs) increase ARDS risk and worsen outcomes through mechanisms that may include enhancement of pulmonary oxidative stress. Alcohol consumption increases activity of the enzyme xanthine oxidoreductase (XOR) that contributes to production of both reactive oxygen species (ROS) and uric acid, a damage-associated molecular pattern. These by-products have the potential to modulate proinflammatory pathways, such as those involving cyclooxygenase (COX)-2, and to activate the nucleotide-binding domain, leucine-rich-containing family, pyrin-domain containing-3 (NLRP3) inflammasome. We sought to determine if pulmonary and systemic XOR activity was altered by AUDs. Bronchoscopy with bronchoalveolar lavage (BAL) and blood sampling was performed in otherwise healthy human subjects with AUDs and controls. Uric acid in epithelial-lining fluid, derived from BAL, was substantially higher among individuals with AUDs and did not normalize after 7 days of abstinence; serum uric acid did not differ across groups. XOR enzyme activity in fresh BAL cells and serum was significantly increased in subjects with AUDs. XOR protein in BAL cells from AUD subjects was increased in parallel with COX-2 expression, and furthermore, mRNA expression of NLRP3 inflammasome components was sustained in LPS-stimulated BAL cells from AUD subjects in conjunction with increased IL-1β. Our data suggest that AUDs augment pulmonary and systemic XOR activity that may contribute to ROS and uric acid generation, promoting inflammation. Further investigations will be necessary to determine if XOR inhibition can mitigate alcohol-associated pulmonary oxidative stress, diminish inflammation, and improve ARDS outcomes.

Malondialdehyde-Acetaldehyde (MAA) Protein Adducts Are Found Exclusively in the Lungs of Smokers with Alcohol Use Disorders and Are Associated with Systemic Anti-MAA Antibodies

BACKGROUND

Malondialdehyde (MDA) and acetaldehyde (AA) exist following ethanol metabolism and tobacco pyrolysis. As such, lungs of individuals with alcohol use disorders (AUDs) are a target for the effects of combined alcohol and cigarette smoke metabolites. MDA and AA form a stable protein adduct, malondialdehyde-acetaldehyde (MAA) adduct, known to be immunogenic, profibrotic, and proinflammatory. MAA adduct is the dominant epitope in anti-MAA antibody formation. We hypothesized that MAA-adducted protein forms in lungs of those who both abuse alcohol and smoke cigarettes, and that this would be associated with systemically elevated anti-MAA antibodies.

METHODS

Four groups were established: AUD subjects who smoked cigarettes (+AUD/+smoke), smokers without AUD (-AUD/+smoke), AUD without smoke (+AUD/-smoke), and non-AUD/nonsmokers (-AUD/-smoke).

RESULTS

We observed a significant increase in MAA adducts in lung cells of +AUD/+smoke versus -AUD/-smoke. No significant increase in MAA adducts was observed in -AUD/+smoke or in +AUD/-smoke compared to -AUD/-smoke. Serum from +AUD/+smoke had significantly increased levels of circulating anti-MAA IgA antibodies. After 1 week of alcohol that MAA-adducted protein is formed in the lungs of those who smoke cigarettes and abuse alcohol, leading to a subsequent increase in serum IgA antibodies.

CONCLUSIONS

MAA-adducted proteins could play a role in pneumonia and other diseases of the lung in the setting of AUD and smoking.

Plasminogen Activator Inhibitor-1 Is Critical in Alcohol-Enhanced Acute Lung Injury in Mice

Chronic alcohol exposure is a clinically important risk factor for the development of acute respiratory distress syndrome, the most severe form of acute lung injury (ALI). However, the mechanisms by which alcohol sensitizes the lung to development of this disease are poorly understood. We determined the role of the antifibrinolytic protein plasminogen activator inhibitor-1 (PAI-1) in alcohol enhancement of experimental endotoxin-induced ALI. Wild-type, PAI-1-/-, and integrin β3-/- mice were fed ethanol-containing Lieber-DeCarli liquid or a control diet for 6 weeks, followed by systemic LPS challenge. LPS administration triggered coagulation cascade activation as evidenced by increased plasma thrombin-antithrombin levels and pulmonary fibrin deposition. Ethanol-exposed animals showed enhanced PAI-1 expression and pulmonary fibrin deposition with coincident exaggeration of pulmonary inflammatory edematous injury. PAI-1 deficiency markedly reduced pulmonary fibrin deposition and greatly reduced inflammation and injury without impacting upstream coagulation. Interestingly, pulmonary platelet accumulation was effectively abolished by PAI-1 deficiency in ethanol/LPS-challenged mice. Moreover, mice lacking integrin αIIBβ3, the primary platelet receptor for fibrinogen, displayed a dramatic reduction in early inflammatory changes after ethanol/LPS challenge. These results indicate that the mechanism whereby alcohol exaggerates LPS-induced lung injury requires PAI-1-mediated pulmonary fibrin accumulation, and suggest a novel mechanism whereby alcohol contributes to inflammatory ALI by enhancing fibrinogen-platelet engagement.

Organ-Organ Crosstalk and Alcoholic Liver Disease

Alcohol consumption is a common custom worldwide, and the toxic effects of alcohol on several target organs are well-understood. Given the poor prognosis of treating clinically-relevant alcoholic liver disease (ALD) (i.e., alcoholic hepatitis (AH) and cirrhosis), additional research is required to develop more effective therapies. While the stages of ALD have been well-characterized, targeted therapies to prevent or reverse this process in humans are still needed. Better understanding of risk factors and mechanisms underlying disease progression can lead to the development of rational therapies to prevent or reverse ALD in the clinic. A potential area of targeted therapy for ALD may be organ–organ communication in the early stages of the disease. In contrast to AH and end-stage liver diseases, the involvement of multiple organs in the development of ALD is less understood. The impact of these changes on pathology to the liver and other organs may not only influence disease progression during the development of the disease, but also outcomes of end stages diseases. The purpose of this review is to summarize the established and proposed communication between the liver and other organ systems that may contribute to the development and progression of liver disease, as well as to other organs. Potential mechanisms of this organ–organ communication are also discussed.

Acute respiratory distress syndrome

Since its first description, the acute respiratory distress syndrome (ARDS) has been acknowledged to be a major clinical problem in respiratory medicine. From July 2015 to July 2016 almost 300 indexed articles were published on ARDS. This review summarises only eight of them as an arbitrary overview of clinical relevance: definition and epidemiology, risk factors, prevention and treatment. A strict application of definition criteria is crucial, but the diverse resource-setting scenarios foster geographic variability and contrasting outcome data. A large international multicentre prospective cohort study including 50 countries across five continents reported that ARDS is underdiagnosed, and there is potential for improvement in its management. Furthermore, epidemiological data from low-income countries suggest that a revision of the current definition of ARDS is needed in order to improve its recognition and global clinical outcome. In addition to the well-known risk-factors for ARDS, exposure to high ozone levels and low vitamin D plasma concentrations were found to be predisposing circumstances. Drug-based preventive strategies remain a major challenge, since two recent trials on aspirin and statins failed to reduce the incidence in at-risk patients. A new disease-modifying therapy is awaited: some recent studies promised to improve the prognosis of ARDS, but mortality and disabling complications are still high in survivors in intensive care.

Massive transfusion: An update for the anesthesiologist

Exsanguination from trauma, gastrointestinal bleeding, and obstetric hemorrhage remains a major source of mortality across the planet. Continued research into resuscitation strategies and evolving technology and blood product storage has allowed for patient to undergo very large volume transfusions, even to the point of replacing a patient’s blood volume several times over. As massive transfusions have become more common, more studies have been performed delineating the exact patient population that would benefit, start- and stop-points of transfusions, complications and avoidance of the same. We discuss these points and provide information and strategies for massive transfusion.

Clinical Predictors of Hospital Mortality Differ Between Direct and Indirect ARDS

BACKGROUND

Direct (pulmonary) and indirect (extrapulmonary) ARDS are distinct syndromes with important pathophysiologic differences. The goal of this study was to determine whether clinical characteristics and predictors of mortality differ between direct or indirect ARDS.

METHODS

This retrospective observational cohort study included 417 patients with ARDS. Each patient was classified as having direct (pneumonia or aspiration, n = 250) or indirect (nonpulmonary sepsis or pancreatitis, n = 167) ARDS.

RESULTS

Patients with direct ARDS had higher lung injury scores (3.0 vs 2.8; P < .001), lower Simplified Acute Physiology Score II scores (51 vs 62; P < .001), lower Acute Physiology and Chronic Health Evaluation II scores (27 vs 30; P < .001), and fewer nonpulmonary organ failures (1 vs 2; P < .001) compared with patients with indirect ARDS. Hospital mortality was similar (28% vs 31%). In patients with direct ARDS, age (OR, 1.29 per 10 years; P = .01; test for interaction, P = .03), lung injury scores (OR, 2.29 per point; P = .001; test for interaction, P = .058), and number of nonpulmonary organ failures (OR, 1.67; P = .01) were independent risk factors for increased hospital mortality. Preexisting diabetes mellitus was an independent risk factor for reduced hospital mortality (OR, 0.47; P = .04; test for interaction, P = .02). In indirect ARDS, only the number of organ failures was an independent predictor of mortality (OR, 2.08; P < .001).

CONCLUSIONS

Despite lower severity of illness and fewer organ failures, patients with direct ARDS had mortality rates similar to patients with indirect ARDS. Factors previously associated with mortality during ARDS were only associated with mortality in direct ARDS. These findings suggest that direct and indirect ARDS have distinct features that may differentially affect risk prediction and clinical outcomes.

The Relationship Between Airway Antioxidant Levels, Alcohol Use Disorders, and Cigarette Smoking

BACKGROUND

Alcohol use disorders (AUDs) and cigarette smoking are associated with pulmonary oxidative stress, likely related to antioxidant depletion. Pulmonary oxidative stress may adversely affect innate immunity, leading to increased pneumonia susceptibility and severity, including development of the acute respiratory distress syndrome. In people with AUDs, most of whom smoke, antioxidant therapy can potentially restore immune cell function and attenuate pneumonia development. Challenges to human investigations of antioxidant therapies include an inability to identify pulmonary oxidative stress noninvasively and the optimal route to deliver pulmonary antioxidants. We sought to determine whether bronchoalveolar lavage (BAL) measures of thiol antioxidants from a 50-ml upper airway aliquot approximated those in the alveolar space and to determine whether AUDs and/or smoking affected these relationships.

METHODS

Healthy human subjects with and without AUDs, including smokers and nonsmokers, underwent BAL. Samples obtained after the first 50-ml normal saline aliquot were analyzed as representing bronchial airways; subsequent 50-ml aliquots were analyzed as representative of the alveolar space. Reduced and oxidized (GSSG) glutathione, cysteine (Cys), and its oxidized species, cystine, along with mixed disulfides (MDs) were quantified using high-performance liquid chromatography. The percent of total thiols present in their oxidized forms, and thiol redox potentials, were calculated.

RESULTS

Positive correlations between upper and lower BAL fluid thiol species were observed that were most robust for GSSG (ρ = 0.85), Cys (ρ = 0.83), and MDs (ρ = 0.69), but poor for thiol redox potential measures. In contrast to nonsmokers (either with or without AUDs), in subjects with AUDs who smoked, upper BAL fluid %GSSG, Cys, and MD measures were relatively increased compared to lower.

CONCLUSIONS

A small volume BAL procedure may be suitable to assess intrapulmonary oxidative stress related to thiol depletion. Factors including AUDs and smoking may disproportionately increase upper airways oxidative stress that could be relevant for therapeutic interventions.