Analgesia and Sedation Use During Noninvasive Ventilation for Acute Respiratory Failure.

OBJECTIVES: To describe U.S. practice regarding administration of sedation and analgesia to patients on noninvasive ventilation (NIV) for acute respiratory failure (ARF) and to determine the association of this practice with odds of intubation or death. DESIGN: A retrospective multicenter cohort study. SETTING: A total of 1017 hospitals contributed data between January 2010 and September 2020 to the Premier Healthcare Database, a nationally representative healthcare database in the United States. PATIENTS: Adult (≥ 18 yr) patients admitted to U.S. hospitals requiring NIV for ARF. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: We identified 433,357 patients on NIV of whom (26.7% [95% CI] 26.3%-27.0%) received sedation or analgesia. A total of 50,589 patients (11.7%) received opioids only, 40,646 (9.4%) received benzodiazepines only, 20,146 (4.6%) received opioids and benzodiazepines, 1.573 (0.4%) received dexmedetomidine only, and 2,639 (0.6%) received dexmedetomidine in addition to opioid and/or benzodiazepine. Of 433,357 patients receiving NIV, 50,413 (11.6%; 95% CI, 11.5-11.7%) patients underwent invasive mechanical ventilation on hospital days 2-5 or died on hospital days 2-30. Intubation was used in 32,301 patients (7.4%; 95% CI, 7.3-7.6%). Further, death occurred in 24,140 (5.6%; 95% CI, 5.5-5.7%). In multivariable analysis adjusting for relevant covariates, receipt of any medication studied was associated with increased odds of intubation or death. In inverse probability weighting, receipt of any study medication was also associated with increased odds of intubation or death (average treatment effect odds ratio 1.38; 95% CI, 1.35-1.40). CONCLUSIONS: The use of sedation and analgesia during NIV is common. Medication exposure was associated with increased odds of intubation or death. Further investigation is needed to confirm this finding and determine whether any subpopulations are especially harmed by this practice.

Association Between Vasopressin Rebranding and Utilization in Patients With Septic Shock.

OBJECTIVES: Vasopressin is suggested as an adjunct to norepinephrine in patients with septic shock. However, after vasopressin was rebranded in November 2014, its cost exponentially increased. Utilization patterns of vasopressin after its rebranding are unclear. The objective of this study was to determine if there is an association between the rebranding of vasopressin in November 2014 and its utilization in vasopressor-dependent patients with severe sepsis or septic shock. DESIGN: Retrospective, multicenter, database study between January 2010 and March 2017. SETTING: Premier Healthcare Database hospitals. PATIENTS: Adult patients admitted to an ICU with severe sepsis or septic shock, who received at least one vasoactive agent for two or more calendar days were included. INTERVENTIONS: The proportion of patients who received vasopressin and vasopressin cost was assessed before and after rebranding, and evaluated with segmented regression. MEASUREMENTS AND MAIN RESULTS: Among 294,733 patients (mean age, 66 ± 15 yr), 27.8% received vasopressin, and ICU mortality was 26.5%. The proportion of patients receiving vasopressin was higher after rebranding (31.2% postrebranding vs 25.8% prerebranding). Before vasopressin rebranding, the quarterly proportion of patients who received vasopressin had an increasing slope (prerebranding slope 0.41% [95% CI, 0.35-0.46%]), with no difference in slope detected after vasopressin rebranding (postrebranding slope, 0.47% [95% CI, 0.29-0.64%]). After vasopressin rebranding, mean vasopressin cost per patient was higher ($527 ± 1,130 vs $77 ± 160), and the quarterly slope of vasopressin cost was higher (change in slope $77.18 [95% CI, $75.73-78.61]). Total vasopressin billed cost postrebranding continually increased by ~$294,276 per quarter from less than $500,000 in Q4 2014 to over $3,000,000 in Q1 2017. CONCLUSIONS: After vasopressin rebranding, utilization continued to increase quarterly despite a significant increase in vasopressin cost. Vasopressin appeared to have price inelastic demand in septic shock.

Upregulation of Chitinase 1 in Alveolar Macrophages of HIV-Infected Smokers.

Recent studies suggest that HIV infection is an independent risk factor for the development of chronic obstructive pulmonary disease (COPD). We hypothesized that HIV infection and cigarette smoking synergize to alter the function of alveolar macrophages (AMs). To test this hypothesis, global transcriptome analysis was performed on purified AMs from 20 individuals split evenly between HIV-uninfected nonsmokers and smokers and untreated HIV-infected nonsmokers and smokers. Differential expression analysis identified 143 genes significantly altered by the combination of HIV infection and smoking. Of the differentially expressed genes, chitinase 1 (CHIT1) and cytochrome P450 family 1 subfamily B member 1 (CYP1B1), both previously associated with COPD, were among the most upregulated genes (5- and 26-fold, respectively) in the untreated HIV-infected smoker cohort compared with HIV-uninfected nonsmokers. Expression of CHIT1 and CYP1B1 correlated with the expression of genes involved in extracellular matrix organization, oxidative stress, immune response, and cell death. Using time-of-flight mass cytometry to characterize AMs, a significantly decreased expression of CD163, an M2 marker, was seen in HIV-infected subjects, and CD163 inversely correlated with CYP1B1 expression in AMs. CHIT1 protein levels were significantly upregulated in bronchoalveolar lavage fluid from HIV-infected smokers, and increased CHIT1 levels negatively correlated with lung function measurements. Overall, these findings raise the possibility that elevated CHIT1 and CYP1B1 are early indicators of COPD development in HIV-infected smokers that may serve as biomarkers for determining this risk.

Noninvasive Ventilation Use in Critically Ill Patients with Acute Asthma Exacerbations.

Rationale: Noninvasive ventilation decreases the need for invasive mechanical ventilation and mortality among patients with chronic obstructive pulmonary disease but has not been well studied in asthma.Objectives: To assess the association between noninvasive ventilation and subsequent need for invasive mechanical ventilation and in-hospital mortality among patients admitted with asthma exacerbation to the ICU.Methods: We performed a retrospective cohort study using administrative data collected during 2010-2017 from 682 hospitals in the United States. Outcomes included receipt of invasive mechanical ventilation and in-hospital mortality. Generalized estimating equations, propensity-matched models, and marginal structural models were used to assess the association between noninvasive ventilation and outcomes.Measurements and Main Results: The study population included 53,654 participants with asthma exacerbation. During the study period, 13,540 patients received noninvasive ventilation (25.2%; 95% confidence interval [CI], 24.9-25.6%), 14,498 underwent invasive mechanical ventilation (27.0%; 95% CI, 26.7-27.4%), and 1,291 died (2.4%; 95% CI, 2.3-2.5%). Among those receiving noninvasive ventilation, 3,013 patients (22.3%; 95% CI, 21.6-23.0%) required invasive mechanical ventilation after first receiving noninvasive ventilation, 136 of whom died (4.5%; 95% CI, 3.8-5.3%). Across all models, the use of noninvasive ventilation was associated with a lower odds of receiving invasive mechanical ventilation (adjusted generalized estimating equation odds ratio, 0.36; 95% CI, 0.32-0.40) and in-hospital mortality (odds ratio, 0.48; 95% CI 0.40-0.58). Those who received noninvasive ventilation before invasive mechanical ventilation were more likely to have comorbid pneumonia and severe sepsis.Conclusions: Noninvasive ventilation use during asthma exacerbation was associated with improved outcomes but should be used cautiously with acute comorbid conditions.

Patterns of utilization and effects of hospital-specific factors on physical, occupational, and speech therapy for critically ill patients with acute respiratory failure in the USA: results of a 5-year sample.

BACKGROUND: Timely initiation of physical, occupational, and speech therapy in critically ill patients is crucial to reduce morbidity and improve outcomes. Over a 5-year time interval, we sought to determine the utilization of these rehabilitation therapies in the USA. METHODS: We performed a retrospective cohort study utilizing a large, national administrative database including ICU patients from 591 hospitals. Patients over 18 years of age with acute respiratory failure requiring invasive mechanical ventilation within the first 2 days of hospitalization and for a duration of at least 48 h were included. RESULTS: A total of 264,137 patients received invasive mechanical ventilation for a median of 4.0 [2.0-8.0] days. Overall, patients spent a median of 5.0 [3.0-10.0] days in the ICU and 10.0 [7.0-16.0] days in the hospital. During their hospitalization, 66.5%, 41.0%, and 33.2% (95% CI = 66.3-66.7%, 40.8-41.2%, 33.0-33.4%, respectively) received physical, occupational, and speech therapy. While on mechanical ventilation, 36.2%, 29.7%, and 29.9% (95% CI = 36.0-36.4%, 29.5-29.9%, 29.7-30.1%) received physical, occupational, and speech therapy. In patients receiving therapy, their first physical therapy session occurred on hospital day 5 [3.0-8.0] and hospital day 6 [4.0-10.0] for occupational and speech therapy. Of all patients, 28.6% (95% CI = 28.4-28.8%) did not receive physical, occupational, or speech therapy during their hospitalization. In a multivariate analysis, patients cared for in the Midwest and at teaching hospitals were more likely to receive physical, occupational, and speech therapy (all P < 0.05). Of patients with identical covariates receiving therapy, there was a median of 61%, 187%, and 70% greater odds of receiving physical, occupational, and speech therapy, respectively, at one randomly selected hospital compared with another (median odds ratio 1.61, 2.87, 1.70, respectively). CONCLUSIONS: Physical, occupational, and speech therapy are not routinely delivered to critically ill patients, particularly while on mechanical ventilation in the USA. The utilization of these therapies varies according to insurance coverage, geography, and hospital teaching status, and at a hospital level.

An Observational Study of the Efficacy of Cisatracurium Compared with Vecuronium in Patients with or at Risk for Acute Respiratory Distress Syndrome.

RATIONALE: The neuromuscular blocking agent cisatracurium may improve mortality for patients with moderate-to-severe acute respiratory distress syndrome (ARDS). Other neuromuscular blocking agents, such as vecuronium, are commonly used and have different mechanisms of action, side effects, cost, and availability in the setting of drug shortages. OBJECTIVES: To determine whether cisatracurium is associated with improved outcomes when compared with vecuronium in patients at risk for and with ARDS. METHODS: Using a nationally representative database, patients who were admitted to the ICU with a diagnosis of ARDS or an ARDS risk factor, received mechanical ventilation, and were treated with a continuous infusion of neuromuscular blocking agent for at least 2 days within 2 days of hospital admission were included. Patients were stratified into two groups: those who received cisatracurium or vecuronium. Propensity matching was used to balance both patient- and hospital-specific factors. Outcomes included hospital mortality, duration of mechanical ventilation, ICU and hospital duration, and discharge location. MEASUREMENTS AND MAIN RESULTS: Propensity matching successfully balanced all covariates for 3,802 patients (1,901 per group). There was no significant difference in mortality (odds ratio, 0.932; P = 0.40) or hospital days (-0.66 d; P = 0.411) between groups. However, patients treated with cisatracurium had fewer ventilator days (-1.01 d; P = 0.005) and ICU days (-0.98 d; P = 0.028) but were equally likely to be discharged home (odds ratio, 1.19; P = 0.056). CONCLUSIONS: When compared with vecuronium, cisatracurium was not associated with a difference in mortality but was associated with improvements in other clinically important outcomes. These data suggest that cisatracurium may be the preferred neuromuscular blocking agent for patients at risk for and with ARDS.

Exhaustion of Airway Basal Progenitor Cells in Early and Established Chronic Obstructive Pulmonary Disease.

RATIONALE: Up to 40% of smokers develop chronic obstructive pulmonary disease (COPD) over a period that spans decades. Despite the importance of COPD, much remains to be learned about susceptibility and pathogenesis, especially during early, prediagnostic stages of disease. Airway basal progenitor cells are crucial for lung health and resilience because of their ability to repair injured airways. In COPD, the normal airway epithelium is replaced with increased basal and secretory (mucous) cells and decreased ciliated cells, suggesting that progenitors are impaired. OBJECTIVES: To examine airway basal progenitor cells and lung function in smokers with and without COPD. METHODS: Bronchial biopsies taken from smokers at risk for COPD and lung cancer were used to acquire airway basal progenitor cells. They were evaluated for count, self-renewal, and multipotentiality (ability to differentiate to basal, mucous, and ciliated cells), and progenitor count was examined for its relationship with lung function. MEASUREMENTS AND MAIN RESULTS: Basal progenitor count, self-renewal, and multipotentiality were all reduced in COPD versus non-COPD. COPD progenitors produced an epithelium with increased basal and mucous cells and decreased ciliated cells, replicating the COPD phenotype. Progenitor depletion correlated with lung function and identified a subset of subjects without COPD with lung function that was midway between non-COPD with high progenitor counts and those with COPD. CONCLUSIONS: Basal progenitor dysfunction relates to the histologic and physiologic manifestations of COPD and identifies a subset that may represent an early, prediagnostic stage of COPD, indicating that progenitor exhaustion is involved in COPD pathogenesis.

The respiratory tract microbial biogeography in alcohol use disorder.

Individuals with alcohol use disorders (AUDs) are at an increased risk of pneumonia and acute respiratory distress syndrome. Data of the lung microbiome in the setting of AUDs are lacking. The objective of this study was to determine the microbial biogeography of the upper and lower respiratory tract in individuals with AUDs compared with non-AUD subjects. Gargle, protected bronchial brush, and bronchoalveolar lavage specimens were collected during research bronchoscopies. Bacterial 16S gene sequencing and phylogenetic analysis was performed, and the alterations to the respiratory tract microbiota and changes in microbial biogeography were determined. The microbial structure of the upper and lower respiratory tract was significantly altered in subjects with AUDs compared with controls. Subjects with AUD have greater microbial diversity [ P < 0.0001, effect size = 16 ± 1.7 observed taxa] and changes in microbial species relative abundances. Furthermore, microbial communities in the upper and lower respiratory tract displayed greater similarity in subjects with AUDs. Alcohol use is associated with an altered composition of the respiratory tract microbiota. Subjects with AUDs demonstrate convergence of the microbial phylogeny and taxonomic communities between distinct biogeographical sites within the respiratory tract. These results support a mechanistic pathway potentially explaining the increased incidence of pneumonia and lung diseases in patients with AUDs.

Half-Dose Versus Full-Dose Alteplase for Treatment of Pulmonary Embolism.

OBJECTIVES: Recent evidence suggests that half-dose thrombolysis for pulmonary embolism may provide similar efficacy with reduced bleeding risk compared with full-dose therapy, but comparative studies are lacking. We aimed to evaluate the effectiveness and safety of half-dose versus full-dose alteplase for treatment of pulmonary embolism. DESIGN: A retrospective cohort study comparing outcomes in patients receiving half-dose (50 mg) versus full-dose (100 mg) alteplase for pulmonary embolism. We used propensity score matching and sensitivity analyses to address confounding and hospital-level clustering. SETTING: Data from 420 hospitals obtained from the Premier Healthcare Database between January 2010 and December 2014. SUBJECTS: Adult critically ill patients with acute pulmonary embolism treated with IV alteplase therapy. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: This study included 3,768 patients: 699 (18.6%) in the half-dose and 3,069 (81.4%) in the full-dose group. At baseline, patients receiving half-dose alteplase required vasopressor therapy (23.3% vs 39.4%; p < 0.01) and invasive ventilation (14.3% vs 28.5%; p < 0.01) less often, compared with full dose. After propensity matching (n = 548 per group), half-dose alteplase was associated with increased treatment escalation (53.8% vs 41.4%; p < 0.01), driven mostly by secondary thrombolysis (25.9% vs 7.3%; p < 0.01) and catheter thrombus fragmentation (14.2% vs 3.8%; p < 0.01). Hospital mortality was similar (13% vs 15%; p = 0.3). There was no difference in cerebral hemorrhage (0.5% vs 0.4%; p = 0.67), gastrointestinal bleeding (1.6% vs 1.6%; p = 0.99), acute blood loss anemia (6.9% vs 4.6%; p = 0.11), use of blood products (p > 0.05 for all), or documented fibrinolytic adverse events (2.6% vs 2.8%; p = 0.82). CONCLUSIONS: Compared with full-dose alteplase, half-dose was associated with similar mortality and rates of major bleeding. Treatment escalation occurred more often in half-dose-treated patients. These results question whether half-dose alteplase provides similar efficacy with improved safety, and highlights the need for further study before use of half-dose alteplase therapy can be routinely recommended in patients with pulmonary embolism.

Outcomes of ICU Patients With a Discharge Diagnosis of Critical Illness Polyneuromyopathy: A Propensity-Matched Analysis.

OBJECTIVES: To assess the impact of a discharge diagnosis of critical illness polyneuromyopathy on health-related outcomes in a large cohort of patients requiring ICU admission. DESIGN: Retrospective cohort with propensity score-matched analysis. SETTING: Analysis of a large multihospital database. PATIENTS: Adult ICU patients without preexisting neuromuscular abnormalities and a discharge diagnosis of critical illness polyneuropathy and/or myopathy along with adult ICU propensity-matched control patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 3,567 ICU patients with a discharge diagnosis of critical illness polyneuropathy and/or myopathy, we matched 3,436 of these patients to 3,436 ICU patients who did not have a discharge diagnosis of critical illness polyneuropathy and/or myopathy. After propensity matching and adjusting for unbalanced covariates, we used conditional logistic regression and a repeated measures model to compare patient outcomes. Compared to patients without a discharge diagnosis of critical illness polyneuropathy and/or myopathy, patients with a discharge diagnosis of critical illness polyneuropathy and/or myopathy had fewer 28-day hospital-free days (6 [0.1] vs 7.4 [0.1] d; p < 0.0001), had fewer 28-day ventilator-free days (15.7 [0.2] vs 17.5 [0.2] d; p < 0.0001), had higher hospitalization charges (313,508 [4,853] vs 256,288 [4,470] dollars; p < 0.0001), and were less likely to be discharged home (15.3% vs 32.8%; p < 0.0001) but had lower in-hospital mortality (13.7% vs 18.3%; p < 0.0001). CONCLUSIONS: In a propensity-matched analysis of a large national database, a discharge diagnosis of critical illness polyneuropathy and/or myopathy is strongly associated with deleterious outcomes including fewer hospital-free days, fewer ventilator-free days, higher hospital charges, and reduced discharge home but also an unexpectedly lower in-hospital mortality. This study demonstrates the clinical importance of a discharge diagnosis of critical illness polyneuropathy and/or myopathy and the need for effective preventive interventions.

Alcohol abuse and smoking alter inflammatory mediator production by pulmonary and systemic immune cells.

Alcohol use disorders (AUDs) and tobacco smoking are associated with an increased predisposition for community-acquired pneumonia and the acute respiratory distress syndrome. Mechanisms are incompletely established but may include alterations in response to pathogens by immune cells, including alveolar macrophages (AMs) and peripheral blood mononuclear cells (PBMCs). We sought to determine the relationship of AUDs and smoking to expression of IFNγ, IL-1ß, IL-6, and TNFα by AMs and PBMCs from human subjects after stimulation with lipopolysaccharide (LPS) or lipoteichoic acid (LTA). AMs and PBMCs from healthy subjects with AUDs and controls, matched on smoking, were cultured with LPS (1 µg/ml) or LTA (5 µg/ml) in the presence and absence of the antioxidant precursor N-acetylcysteine (10 mM). Cytokines were measured in cell culture supernatants. Expression of IFNγ, IL-1ß, IL-6, and TNFα in AMs and PBMCs was significantly increased in response to stimulation with LPS and LTA. AUDs were associated with augmented production of proinflammatory cytokines, particularly IFNγ and IL-1ß, by AMs and PBMCs in response to LPS. Smoking diminished the impact of AUDs on AM cytokine expression. Expression of basal AM and PBMC Toll-like receptors-2 and -4 was not clearly related to differences in cytokine expression; however, addition of N-acetylcysteine with LPS or LTA led to diminished AM and PBMC cytokine secretion, especially among current smokers. Our findings suggest that AM and PBMC immune cell responses to LPS and LTA are influenced by AUDs and smoking through mechanisms that may include alterations in cellular oxidative stress.

Cigarette smokers have exaggerated alveolar barrier disruption in response to lipopolysaccharide inhalation.

RATIONALE: Cigarette smoke exposure is associated with an increased risk of the acute respiratory distress syndrome (ARDS); however, the mechanisms underlying this relationship remain largely unknown. OBJECTIVE: To assess pathways of lung injury and inflammation in smokers and non-smokers with and without lipopolysaccharide (LPS) inhalation using established biomarkers. METHODS: We measured plasma and bronchoalveolar lavage (BAL) biomarkers of inflammation and lung injury in smokers and non-smokers in two distinct cohorts of healthy volunteers, one unstimulated (n=20) and one undergoing 50 µg LPS inhalation (n=30). MEASUREMENTS AND MAIN RESULTS: After LPS inhalation, cigarette smokers had increased alveolar-capillary membrane permeability as measured by BAL total protein, compared with non-smokers (median 274 vs 208 µg/mL, p=0.04). Smokers had exaggerated inflammation compared with non-smokers, with increased BAL interleukin-1ß (p=0.002), neutrophils (p=0.02), plasma interleukin-8 (p=0.003), and plasma matrix metalloproteinase-8 (p=0.006). Alveolar epithelial injury after LPS was more severe in smokers than non-smokers, with increased plasma (p=0.04) and decreased BAL (p=0.02) surfactant protein D. Finally, smokers had decreased BAL vascular endothelial growth factor (VEGF) (p<0.0001) with increased soluble VEGF receptor-1 (p=0.0001). CONCLUSIONS: Cigarette smoke exposure may predispose to ARDS through an abnormal response to a 'second hit,' with increased alveolar-capillary membrane permeability, exaggerated inflammation, increased epithelial injury and endothelial dysfunction. LPS inhalation may serve as a useful experimental model for evaluation of the acute pulmonary effects of existing and new tobacco products.

Speckle Tracking Echocardiography to Evaluate for Pulmonary Hypertension in Chronic Obstructive Pulmonary Disease.

Pulmonary hypertension (PH) is a common complication of chronic obstructive pulmonary disease (COPD), increasing morbidity and mortality. Current echocardiographic measures have poor predictive value for the diagnosis of PH in COPD. Right ventricular (RV) strain obtained by speckle tracking echocardiography (STE) is a measure of myocardial deformation which correlates with RV function and survival in subjects with pulmonary arterial hypertension. We hypothesized that RV strain measurements would be feasible and correlate with invasive hemodynamic measurements in patients with COPD. Retrospective analysis of RV strain values from subjects with severe COPD with echocardiogram within 48 hours of right heart catheterization was performed. First, 54 subjects were included in the analysis. Right ventricular systolic pressure (RVSP) and RV strain could be estimated in 31% and 57%, respectively. Then, 61% had RV-focused apical views, and of those, RV strain could be obtained for 94%. RV free wall strain correlated with PVR (r = 0.41, p = 0.02). Subjects with pulmonary vascular resistance (PVR) > 3 Wood units (WU) had less negative (worse) RV free wall strain values than those with PVR ≤ 3 WU, with a median strain of -20 (-23, -12) versus -23 (-29, -15), p < 0.05. A receiver operating characteristic curve demonstrated an RV free wall strain of > -23 to be 92% sensitive and 44% specific for identifying PVR > 3 WU (AUC 0.71). RV strain estimates are feasible in the majority of subjects with severe COPD. RV strain correlates with PVR and may improve screening for PH in subjects with COPD.

Neuroendocrine signaling via the serotonin transporter regulates clearance of apoptotic cells.

Serotonin (5-hydroxytryptamine; 5-HT) is a CNS neurotransmitter increasingly recognized to exert immunomodulatory effects outside the CNS that contribute to the pathogenesis of autoimmune and chronic inflammatory diseases. 5-HT signals to activate the RhoA/Rho kinase (ROCK) pathway, a pathway known for its ability to regulate phagocytosis. The clearance of apoptotic cells (i.e. efferocytosis) is a key modulator of the immune response that is inhibited by the RhoA/ROCK pathway. Because efferocytosis is defective in many of the same illnesses where 5-HT has been implicated in disease pathogenesis, we hypothesized that 5-HT would suppress efferocytosis via activation of RhoA/ROCK. The effect of 5-HT on efferocytosis was examined in murine peritoneal and human alveolar macrophages, and its mechanisms were investigated using pharmacologic blockade and genetic deletion. 5-HT impaired efferocytosis by murine peritoneal macrophages and human alveolar macrophages. 5-HT increased phosphorylation of myosin phosphatase subunit 1 (Mypt-1), a known ROCK target, and inhibitors of RhoA and ROCK reversed the suppressive effect of 5-HT on efferocytosis. Peritoneal macrophages expressed the 5-HT transporter and 5-HT receptors (R) 2a, 2b, but not 2c. Inhibition of 5-HTR2a and 5-HTR2b had no effect on efferocytosis, but blockade of the 5-HT transporter prevented 5-HT-impaired efferocytosis. Genetic deletion of the 5-HT transporter inhibited 5-HT uptake into peritoneal macrophages, prevented 5-HT-induced phosphorylation of Mypt-1, reversed the inhibitory effect of 5-HT on efferocytosis, and decreased cellular peritoneal inflammation. These results suggest a novel mechanism by which 5-HT might disrupt efferocytosis and contribute to the pathogenesis of autoimmune and chronic inflammatory diseases.

Severe acute exacerbations of chronic obstructive pulmonary disease: does the dosage of corticosteroids and type of antibiotic matter?

PURPOSE OF REVIEW: Severe acute exacerbations of chronic obstructive pulmonary disease (AECOPD) are significant events that result in substantial morbidity and mortality. Antibiotic therapy and systemic corticosteroids are important treatments for patients with severe AECOPD. The objective of this review is to summarize the most recent evidence concerning antibiotic and corticosteroid therapy, with a focused evaluation on the contribution of antibiotic type and corticosteroid dosage on patient outcomes. RECENT FINDINGS: Macrolides should be considered the antibiotic of choice for prevention of AECOPD in patients who qualify for therapy. Macrolides, fluoroquinolones, and beta-lactams are all reasonable treatment options for severe AECOPD and the decision to use one over the other should be based upon patient characteristics and institutional or regional antimicrobial susceptibility patterns. The best available evidence now suggests that higher-dose corticosteroids are not superior to treatment with lower-dose corticosteroids in patients with severe AECOPD. Additionally, longer durations of systemic corticosteroid therapy do not improve clinical outcomes. SUMMARY: Several antibiotic options are efficacious in the management of severe AECOPD and drug selection should be patient-specific. Recent studies suggest that lower dosages and shorter durations of corticosteroid treatment may be prudent.

Outcomes associated with corticosteroid dosage in critically ill patients with acute exacerbations of chronic obstructive pulmonary disease.

RATIONALE: Studies evaluating corticosteroid (CS) dosing for patients hospitalized with an acute exacerbation of chronic obstructive pulmonary disease (AECOPD) have largely excluded patients admitted directly to the intensive care unit (ICU), and none have evaluated the effect of CS dosing regimens on mortality. OBJECTIVES: To examine the effectiveness and safety of lower- versus high-dose CS in patients admitted to the ICU with an AECOPD. METHODS: This pharmacoepidemiologic cohort study evaluated ICU patients with AECOPD admitted to one of 473 hospitals and treated with CS within the first 2 days between January 1, 2003 and December 31, 2008. Patients were grouped into lower-dose (methylprednisolone, ≤240 mg/d) or high-dose (methylprednisolone, >240 mg/d) groups based on CS dosage on hospital Day 1 or 2. The primary outcome was hospital mortality. MEASUREMENTS AND MAIN RESULTS: A total of 17,239 patients were included; 6,156 (36%) were in the lower-dose and 11,083 (64%) in the high-dose CS group. After propensity score matching and adjustment for unbalanced covariates, lower-dose CS was not associated with a significant reduction in mortality (odds ratio, 0.85; 95% confidence interval [CI], 0.71-1.01; P = 0.06), but it was associated with reduced hospital (-0.44 d; 95% CI, -0.67 to -0.21; P < 0.01) and ICU (-0.31 d; 95% CI, -0.46 to -0.16; P < 0.01) length-of-stay, hospital costs (-$2,559; 95% CI, -$4,508 to -$609; P = 0.01), length of invasive ventilation (-0.29 d; 95% CI, -0.52 to -0.06; P = 0.01), need for insulin therapy (22.7% vs. 25.1%; P < 0.01), and fungal infections (3.3% vs. 4.4%; P < 0.01). CONCLUSIONS: Two-thirds of patients admitted to the ICU with an AECOPD are treated with high doses of CS that are associated with worse outcomes and more frequent adverse effects. Lower dosage strategies should be encouraged for patients admitted to the ICU and the optimum dose should be determined through clinical trials.

Transforming growth factor-ß signaling promotes pulmonary hypertension caused by Schistosoma mansoni.

BACKGROUND: The pathogenic mechanisms underlying pulmonary arterial hypertension resulting from schistosomiasis, one of the most common causes of pulmonary hypertension worldwide, remain unknown. We hypothesized that transforming growth factor-ß (TGF-ß) signaling as a consequence of Th2 inflammation is critical for the pathogenesis of this disease. METHODS AND RESULTS: Mice sensitized and subsequently challenged with Schistosoma mansoni eggs developed pulmonary hypertension associated with an increase in right ventricular systolic pressure, thickening of the pulmonary artery media, and right ventricular hypertrophy. Rho-kinase-dependent vasoconstriction accounted for ≈60% of the increase in right ventricular systolic pressure. The pulmonary vascular remodeling and pulmonary hypertension were dependent on increased TGF-ß signaling, as pharmacological blockade of the TGF-ß ligand and receptor, and mice lacking Smad3 were significantly protected from Schistosoma-induced pulmonary hypertension. Blockade of TGF-ß signaling also led to a decrease in interleukin-4 and interleukin-13 concentrations, which drive the Th2 responses characteristic of schistosomiasis lung pathology. Lungs of patients with schistosomiasis-associated pulmonary arterial hypertension have evidence of TGF-ß signaling in their remodeled pulmonary arteries. CONCLUSION: Experimental S mansoni-induced pulmonary vascular disease relies on canonical TGF-ß signaling.

Early administration of infliximab for severe ipilimumab-related diarrhea in a critically ill patient.

OBJECTIVE: To report a case of ipilimumab-associated life-threatening diarrhea responding quickly to a single dose of infliximab. CASE SUMMARY: A 67-year-old man presented 3 weeks after his second dose of ipilimumab with severe diarrhea, acute kidney injury, and hypotension. After 2 days of high-dose corticosteroids and supportive care, he continued to have 2.8 L of stool output per day (grade 4 National Cancer Institute Common Terminology Criteria for Adverse Events). The patient was transferred to the medical intensive care unit requiring endotracheal intubation because of concerns of worsening mental status, metabolic acidosis, and increased work of breathing, with a serum bicarbonate concentration of <5 mmol/L. Despite aggressive fluid resuscitation and a sodium bicarbonate infusion, he remained hypotensive and hyponatremic with persistent premature ventricular contractions. On the evening of day 3, infliximab (5 mg/kg) was given, resulting in a rapid decrease in diarrhea. After 48 hours, the acidosis was corrected and electrolytes, renal function, and fluid status were improving. At discharge, diarrhea, acute kidney injury, and acidosis had resolved, and he was discharged on a slow steroid taper. DISCUSSION: Autoimmune colitis is a described immune-related adverse event of ipilimumab. Prompt recognition, initiation of steroids, and supportive therapy are key to the management of diarrhea. Infliximab should be considered early in steroid-nonresponsive or life-threatening diarrhea. CONCLUSION: Infliximab is a life-saving intervention in patients with ipilimumab-induced diarrhea.