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 Substance Misuse and Outcomes in Critically III Patients with Pneumonia.

Rationale: In patients with pneumonia requiring intensive care unit (ICU) admission, alcohol misuse is associated with increased mortality, but the relationship between other commonly misused substances and mortality is unknown. Objectives: We sought to establish whether alcohol misuse, cannabis misuse, opioid misuse, stimulant misuse, or misuse of more than one of these substances was associated with differences in mortality among ICU patients with pneumonia. Methods: This was a retrospective cohort study of hospitals participating in the Premier Healthcare Database between 2010 and 2017. Patients were included if they had a primary or secondary diagnosis of pneumonia and received antibiotics or antivirals within 1 day of admission. Substance misuse related to alcohol, cannabis, stimulants, and opioids, or more than one substance, were identified from the International Classification of Diseases (Ninth and Tenth Editions). The associations between substance misuse and in-hospital mortality were the primary outcomes of interest. Secondary outcomes included the measured associations between substance misuse disorders and mechanical ventilation, as well as vasopressor and continuous paralytic administration. Analyses were conducted with multivariable mixed-effects logistic regression modeling adjusting for age, comorbidities, and hospital characteristics. Results: A total of 167,095 ICU patients met inclusion criteria for pneumonia. Misuse of alcohol was present in 5.0%, cannabis misuse in 0.6%, opioid misuse in 1.5%, stimulant misuse in 0.6%, and misuse of more than one substance in 1.2%. No evidence of substance misuse was found in 91.1% of patients. In unadjusted analyses, alcohol misuse was associated with increased in-hospital mortality (odds ratio [OR], 1.12; 95% confidence interval [CI], 1.06-1.19), whereas opioid misuse was associated with decreased in-hospital mortality (OR, 0.46; 95% CI, 0.39-0.53) compared with no substance misuse. These findings persisted in adjusted analyses. Although cannabis, stimulant, and more than one substance misuse (a majority of which were alcohol in combination with another substance) were associated with lower odds for in-hospital mortality in unadjusted analyses, these relationships were not consistently present after adjustment. Conclusions: In this study of ICU patients hospitalized with severe pneumonia, substance misuse subtypes were associated with different effects on mortality. Although administrative data can provide epidemiologic insight regarding substance misuse and pneumonia outcomes, biases inherent to these data should be considered when interpreting results.

Extracorporeal Membrane Oxygenation for Refractory Asthma Exacerbations With Respiratory Failure.

BACKGROUND: Asthma exacerbations with respiratory failure (AERF) are associated with hospital mortality of 7% to 15%. Extracorporeal membrane oxygenation (ECMO) has been used as a salvage therapy for refractory AERF, but controlled studies showing its association with mortality have not been performed. RESEARCH QUESTION: Is treatment with ECMO associated with lower mortality in refractory AERF compared with standard care? STUDY DESIGN AND METHODS: This is a retrospective, epidemiologic, observational cohort study using a national, administrative data set from 2010 to 2020 that includes 25% of US hospitalizations. People were included if they were admitted to an ECMO-capable hospital with an asthma exacerbation, and were treated with short-acting bronchodilators, systemic corticosteroids, and invasive ventilation. People were excluded for age < 18 years, no ICU stay, nonasthma chronic lung disease, COVID-19, or multiple admissions. The main exposure was ECMO vs No ECMO. The primary outcome was hospital mortality. Key secondary outcomes were ICU length of stay (LOS), hospital LOS, time receiving invasive ventilation, and total hospital costs. RESULTS: The study analyzed 13,714 patients with AERF, including 127 with ECMO and 13,587 with No ECMO. ECMO was associated with reduced mortality in the covariate-adjusted (OR, 0.33; 95% CI, 0.17-0.64; P = .001), propensity score-adjusted (OR, 0.36; 95% CI, 0.16-0.81; P = .01), and propensity score-matched models (OR, 0.48; 95% CI, 0.24-0.98; P = .04) vs No ECMO. Sensitivity analyses showed that mortality reduction related to ECMO ranged from OR 0.34 to 0.61. ECMO was also associated with increased hospital costs in all three models (P < .0001 for all) vs No ECMO, but not with decreased ICU LOS, hospital LOS, or time receiving invasive ventilation. INTERPRETATION: ECMO was associated with lower mortality and higher hospital costs, suggesting that it may be an important salvage therapy for refractory AERF following confirmatory clinical trials.

Impact of Airline Secondhand Tobacco Smoke Exposure on Respiratory Health and Lung Function Decades After Exposure Cessation.

BACKGROUND: Twenty-five percent to 45% of COPD is caused by exposures other than active smoking. Secondhand tobacco smoke (SHS) has been suggested as an independent cause of COPD, based on its association with increased respiratory symptoms and a small decrease in lung function, but its impact on respiratory health and lung function after exposure cessation has not been explored. RESEARCH QUESTION: What are the consequences of airline SHS exposure on respiratory health and lung function decades after cessation? STUDY DESIGN AND METHODS: We performed a cohort study involving flight attendants because of their exposure to SHS that stopped > 20 years ago. We included subjects ≥ 50 years of age with > 1 year vs ≤ 1 year of airline SHS exposure (ie, exposed vs unexposed). Respiratory quality of life, as determined by the St. George's Respiratory Questionnaire (SGRQ), was the primary outcome for respiratory health. Key secondary outcomes included general quality of life (the Rand Corporation modification of the 36-item Short Form Health Survey Questionnaire; RAND-36), respiratory symptoms (COPD Assessment Test; CAT), and spirometry. RESULTS: The study enrolled 183 SHS-exposed and 59 unexposed subjects. Exposed subjects were 66.7 years of age, and 90.7% were female. They were hired at 23.8 years of age, were exposed to airline SHS for 16.1 years, and stopped exposure 27.5 years before enrollment. Prior SHS exposure was associated with worsened SGRQ (6.7 units; 95% CI, 2.7-10.7; P = .001), RAND-36 physical and social function, and CAT vs unexposed subjects. SHS exposure did not affect prebronchodilator spirometry or obstruction, but was associated with lower postbronchodilator FEV1 and FEV1/FVC, total lung capacity, and diffusing capacity of the lungs for carbon monoxide in a subset of subjects. Former smoking and SHS exposure synergistically worsened SGRQ (ß = 8.4; 95% CI, 0.4-16.4; P = .04). SHS exposure in people who never smoked replicated primary results and was associated with worsened SGRQ vs unexposed people (4.7 units; 95% CI, 0.7-7.0; P = .006). INTERPRETATION: Almost three decades after exposure ended, airline SHS exposure is strongly and dose-dependently associated with worsened respiratory health, but less robustly associated with airflow abnormalities used to diagnose COPD.

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.

Challenges Faced by Rural Primary Care Providers When Caring for COPD Patients in the Western United States.

RATIONALE: Rural chronic obstructive pulmonary disease (COPD) patients have worse outcomes and higher mortality compared with urban patients. Reasons for these disparities likely include challenges to delivery of care that have not been explored. OBJECTIVE: To determine challenges faced by rural primary care providers when caring for COPD patients. METHODS: Rural primary care providers in 7 primarily western states were asked about barriers they experienced when caring for COPD patients. RESULTS: A total of 71 rural primary care medical providers completed the survey, of which 51% were physicians and 49% were advanced practice providers (APPs). A total of 61% used Global Initiative for Chronic Obstructive Lung Disease or American Thoracic Society/European Respiratory Society guidelines as an assessment and treatment resource. The presence of multiple chronic conditions and patient failure to recognize and report symptoms were the greatest barriers to diagnose COPD. A total of 89% of providers used spirometry to diagnose COPD, but only 62% were satisfied with access to spirometry. Despite recommendations, 41% of providers never test for alpha-1 antitrypsin deficiency. A total of 87% were comfortable with their ability to assess symptoms, but only 11% used a guideline-recommended assessment tool. Although most providers were satisfied with their ability to treat symptoms and exacerbations, only 66% were content with their ability to prevent exacerbations. Fewer providers were happy with their access to pulmonologists (55%) or pulmonary rehabilitation (37%). Subgroup analyses revealed differences based on provider type (APP versus physician) and location (Colorado and Kansas versus other states), but not on population or practice size. CONCLUSIONS: Rural providers face significant challenges when caring for COPD patients that should be targeted in future interventions to improve COPD outcomes.

Impact of Proactive Integrated Care on Chronic Obstructive Pulmonary Disease.

BACKGROUND: Up to 50% of chronic obstructive pulmonary disease (COPD) patients do not receive recommended care for COPD. To address this issue, we developed Proactive Integrated Care (Proactive iCare), a health care delivery model that couples integrated care with remote monitoring. METHODS: We conducted a prospective, quasi-randomized clinical trial in 511 patients with advanced COPD or a recent COPD exacerbation, to test whether Proactive iCare impacts patient-centered outcomes and health care utilization. Patients were allocated to Proactive iCare (n=352) or Usual Care ( =159) and were examined for changes in quality of life using the St George's Respiratory Questionnaire (SGRQ), symptoms, guideline-based care, and health care utilization. FINDINGS: Proactive iCare improved total SGRQ by 7-9 units (p < 0.0001), symptom SGRQ by 9 units (p<0.0001), activity SGRQ by 6-7 units (p<0.001) and impact SGRQ by 7-11 units (p<0.0001) at 3, 6 and 9 months compared with Usual Care. Proactive iCare increased the 6-minute walk distance by 40 m (p<0.001), reduced annual COPD-related urgent office visits by 76 visits per 100 participants (p<0.0001), identified unreported exacerbations, and decreased smoking (p=0.01). Proactive iCare also improved symptoms, the body mass index-airway obstruction-dyspnea-exercise tolerance (BODE) index and oxygen titration (p<0.05). Mortality in the Proactive iCare group (1.1%) was not significantly different than mortality in the Usual Care group (3.8%; p=0.08). INTERPRETATION: Linking integrated care with remote monitoring improves the lives of people with advanced COPD, findings that may have been made more relevant by the coronavirus 2019 (COVID-19) pandemic.

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.

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.

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.

African Americans Are Less Likely to Receive Care by a Cardiologist During an Intensive Care Unit Admission for Heart Failure.

OBJECTIVES: This study sought to determine whether the likelihood of receiving primary intensive care unit (ICU) care by a cardiologist versus a noncardiologist was greater for Caucasians than for African Americans admitted to an ICU for heart failure (HF). The authors further evaluated whether primary ICU care by a cardiologist is associated with higher in-hospital survival, irrespective of race. BACKGROUND: Increasing data demonstrate an association between better HF outcomes and care by a cardiologist. It is unclear if previously noted racial differences in cardiology care persist in an ICU setting. METHODS: Using the Premier database, adult patients admitted to an ICU with a primary discharge diagnosis of HF from 2010 to 2014 were included. Hierarchical logistic regression models were used to determine the association between race and primary ICU care by a cardiologist, adjusting for patient and hospital variables. Cox regression with inverse probability weighting was used to assess the association between cardiology care and in-hospital mortality. RESULTS: Among 104,835 patients (80.3% Caucasians, 19.7% African Americans), Caucasians had higher odds of care by a cardiologist than African Americans (adjusted odds ratio: 1.42; 95% confidence interval: 1.34 to 1.51). Compared with a noncardiologist, primary ICU care by a cardiologist was associated with higher in-hospital survival (adjusted hazard ratio: 1.20, 95% confidence interval: 1.11 to 1.28). The higher likelihood of survival did not differ by patient race (interaction p = 0.32). CONCLUSIONS: Among patients admitted to an ICU for HF, African Americans were less likely than Caucasians to receive primary care by a cardiologist. Primary care by a cardiologist was associated with higher survival for both Caucasians and African Americans.

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.

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.

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.

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.

A Survey of Corticosteroid Dosing for Exacerbations of Chronic Obstructive Pulmonary Disease Requiring Assisted Ventilation.

Background: For over 40 years, systemic corticosteroids have been a mainstay of treatment for patients with exacerbations of chronic obstructive pulmonary disease (COPD). Surprisingly, the optimal dosage of corticosteroids is unknown in critically ill patients requiring assisted ventilation, a group with high morbidity and mortality. Methods: We surveyed 39 academic physicians within the United States Critical Illness and Injury Trials Group (USCIITG) and the Prevention and Early Treatment of Acute Lung Injury Trials Network (PETAL) to determine the range of corticosteroid dosages used to treat patients with COPD exacerbations requiring assisted ventilation. We also asked if these physicians believe that a clinical trial is needed to determine the optimal dosage of corticosteroids in this population. Results: Thirty-two physicians (82%) responded to the survey. Usual practice was to start intravenous methylprednisolone at a median dose of 120 mg/day (range 40-500 mg/day). In the context of a clinical trial, 78% of physicians were comfortable initiating methylprednisolone at a dose as low as 40 mg/day. In contrast, physicians were split on the highest acceptable methylprednisolone dose, with 44% comfortable initiating doses as high as 500 mg/day, 44% at 240 mg/day, and 12% at doses less than 240 mg/day. Ninety-four percent of respondents believed that a randomized controlled trial is needed to determine the optimal corticosteroid dose to treat patients with COPD exacerbations requiring assisted ventilation. Conclusions: These results demonstrate sufficient clinical equipoise to support the conduct of a clinical trial to identify the optimal dose of systemic corticosteroids for patients with COPD exacerbations requiring assisted ventilation.