Oral Albuterol Treatment in Three Pediatric Patients with Bradycardia: A Novel Therapy.

Clinically significant bradycardia is an uncommon problem in children, but one that can cause significant morbidity and sometimes necessitates implantation of a pacemaker. The most common causes of bradycardia are complete heart block (CHB), which can be congenital or acquired, and sinus node dysfunction, which is rare in children with structurally normal hearts. Pacemaker is indicated as therapy for the majority of children with CHB, and while early mortality is lower in postnatally diagnosed CHB than in fetal CHB, it is still up to 16%. In young children, less invasive transvenous pacemaker systems can be technically challenging to place and carry a high risk of complications, often necessitating surgical epicardial pacemaker placement, which usually entails a median sternotomy. We report three cases of pediatric patients referred for pacemaker implantation for different types of bradycardia, treated at our institution with oral albuterol with therapeutic results that avoided the need for surgical pacemaker implantation at that time.

Multi-omic approach associates blood methylome with bronchodilator drug response in pediatric asthma.

BACKGROUND: Albuterol is the drug most widely used as asthma treatment among African Americans despite having a lower bronchodilator drug response (BDR) than other populations. Although BDR is affected by gene and environmental factors, the influence of DNA methylation is unknown. OBJECTIVE: This study aimed to identify epigenetic markers in whole blood associated with BDR, study their functional consequences by multi-omic integration, and assess their clinical applicability in admixed populations with a high asthma burden. METHODS: We studied 414 children and young adults (8-21 years old) with asthma in a discovery and replication design. We performed an epigenome-wide association study on 221 African Americans and replicated the results on 193 Latinos. Functional consequences were assessed by integrating epigenomics with genomics, transcriptomics, and environmental exposure data. Machine learning was used to develop a panel of epigenetic markers to classify treatment response. RESULTS: We identified 5 differentially methylated regions and 2 CpGs genome-wide significantly associated with BDR in African Americans located in FGL2 (cg08241295, P = 6.8 × 10-9) and DNASE2 (cg15341340, P = 7.8 × 10-8), which were regulated by genetic variation and/or associated with gene expression of nearby genes (false discovery rate < 0.05). The CpG cg15341340 was replicated in Latinos (P = 3.5 × 10-3). Moreover, a panel of 70 CpGs showed good classification for those with response and nonresponse to albuterol therapy in African American and Latino children (area under the receiver operating characteristic curve for training, 0.99; for validation, 0.70-0.71). The DNA methylation model showed similar discrimination as clinical predictors (P > .05). CONCLUSIONS: We report novel associations of epigenetic markers with BDR in pediatric asthma and demonstrate for the first time the applicability of pharmacoepigenetics in precision medicine of respiratory diseases.

New Air-Jet Dry Powder Insufflator for High-Efficiency Aerosol Delivery to Rats.

Pulmonary deposition of lung-targeted therapeutic aerosols can achieve direct drug delivery to the site of action, thereby enhancing the efficacy and reducing systemic exposure. In this study, we investigated the in vitro and in vivo aerosol performance of the novel small animal air-jet dry powder insufflator (Rat AJ DPI) using spray-dried albuterol excipient-enhanced-growth (EEG) powder as a model formulation. The in vitro aerosolization performance of the optimized albuterol EEG powder was first assessed using the Rat AJ DPI. The performance of Rat AJ DPI to deliver albuterol EEG aerosol to rat lungs was then compared to that of the Penn-Century Insufflator. Albuterol EEG powders dispersed using the Rat AJ DPI demonstrated narrow unimodal aerosol size distribution profiles, which were independent of the loaded powder dose (1, 2, and 5 mg). In addition, the span value for Rat AJ DPI (5 mg powder mass) was 1.32, which was 4.2-fold lower than that for Penn-Century insufflator (5 mg powder mass). At a higher loaded mass of 5 mg, the Rat AJ DPI delivered significantly larger doses to rat lungs compared with the Penn-Century DPI. The Rat AJ DPI with hand actuation delivered approximately 85% of the total emitted dose (2 and 5 mg loadings), which was comparatively higher than that for Penn-Century DPI (approximately 75%). In addition, percentage deposition in each of the lung lobes for the Rat AJ DPI was observed to be independent of the administration dose (2 and 5 mg loadings) with coefficients of variation below 12%, except in the right middle lobe. Automatic actuation of a 5 mg powder mass using the Rat AJ DPI demonstrated a similar delivered dose compared to manual actuation of the same dose, with 82% of the total emitted dose reaching the lung lobes. High-efficiency delivery of the aerosol to the lobar lung region and low sensitivity of the interlobar delivery efficiency to the loaded dose highlight the suitability of the new air-jet DPI for administering therapeutic pharmaceutical aerosols to small test animals.

Role of ethnicity/language in documented rates of pediatric asthma prescription refills.

OBJECTIVE: Medication maintenance is critical in the management of asthma. We investigated the differences in electronic health record (EHR) documentation of medication refills for Spanish- and English-speaking Latino children and non-Hispanic white children by examining rates of albuterol rescue inhaler refills from 2005 to 2017, and and inhaled corticosteroid refills from 2015 to 2017 in a multi-state network of community health centers (CHCs). METHODS: We used data from the ADVANCE network of CHCs. Our sample consisted of children aged 3-17, with a diagnosis of asthma and either albuterol or inhaled corticosteroid prescriptions (n = 39,162; n = 4,738 children, respectively). Negative binomial regression was used to calculate rates of refills per prescription adjusted for relevant patient-level covariates. Analyses stratified by asthma severity were also conducted. RESULTS: English-speaking Latino children had lower rates of albuterol refills compared with non-Hispanic white children (rate ratio [RR] = 0.88, 95% confidence interval [CI]: 0.80-0.98), a trend that persisted among children with moderate/severe persistent asthma severity (RR = 0.85, 95% CI: 0.76-0.95). Spanish-speaking Latino and non-Hispanic white children had similar albuterol refills. Inhaled corticosteroid refill rates were comparable between all groups. CONCLUSIONS: In a multi-state network, these findings suggest that CHCs deliver equitable asthma care related to prescription refills between their Latino and white patients, but there is still opportunity for providers to ensure that their English-speaking Latino patients have access to necessary emergency asthma medication.

Clinical and Pathologic Features of Congenital Myasthenic Syndromes Caused by 35 Genes-A Comprehensive Review.

Congenital myasthenic syndromes (CMS) are a heterogeneous group of disorders characterized by impaired neuromuscular signal transmission due to germline pathogenic variants in genes expressed at the neuromuscular junction (NMJ). A total of 35 genes have been reported in CMS (AGRN, ALG14, ALG2, CHAT, CHD8, CHRNA1, CHRNB1, CHRND, CHRNE, CHRNG, COL13A1, COLQ, DOK7, DPAGT1, GFPT1, GMPPB, LAMA5, LAMB2, LRP4, MUSK, MYO9A, PLEC, PREPL, PURA, RAPSN, RPH3A, SCN4A, SLC18A3, SLC25A1, SLC5A7, SNAP25, SYT2, TOR1AIP1, UNC13A, VAMP1). The 35 genes can be classified into 14 groups according to the pathomechanical, clinical, and therapeutic features of CMS patients. Measurement of compound muscle action potentials elicited by repetitive nerve stimulation is required to diagnose CMS. Clinical and electrophysiological features are not sufficient to identify a defective molecule, and genetic studies are always required for accurate diagnosis. From a pharmacological point of view, cholinesterase inhibitors are effective in most groups of CMS, but are contraindicated in some groups of CMS. Similarly, ephedrine, salbutamol (albuterol), amifampridine are effective in most but not all groups of CMS. This review extensively covers pathomechanical and clinical features of CMS by citing 442 relevant articles.

Evaluation of intratracheal salbutamol effects in addition to surfactant in the clinical course of premature neonates with respiratory distress syndrome.

Background: In addition to surfactant deficiency, secretion of fluid from blood to the lungs and increase in the fluid content of the lung play significant roles in the pathogenesis of respiratory distress syndrome (RDS). Thus, we aimed to evaluate the effect of salbutamol (a beta-agonist) on fluid clearance from the lungs in neonates with RDS. Materials and Methods: This randomized controlled clinical trial included 82 neonates with RDS admitted to the neonatal intensive care units of Alzahra and Shahid Beheshti Hospitals of Isfahan University of Medical Science from 2017 to 2018. Patients were recruited through convenience sampling. They were randomized into two groups, using simple randomization: 42 were only treated with intra-tracheal surfactant (control group) and 40 with intra-tracheal surfactant plus salbutamol (intervention group). The two groups were compared regarding intubation surfactant administration and extubation (INSURE) failure, duration of nasal continuous positive airway pressure, intubation, oxygen therapy, morbidity, and mortality. Results: INSURE failure leading to mechanical ventilation occurred in 3 neonates in the control group and 2 in the intervention group (P = 0.680). Mean hospital length of stay did not differ significantly between groups (P = 0.230). Comparison of controls with the intervention group regarding complications and the incidence of morbidities revealed no statistically significant difference (P > 0.05). Conclusion: Findings of this study were not in favor of the routine use of salbutamol in neonates with RDS as it did not improve the course of the disease among newborns.

Association between dispensing of low-value oral albuterol and removal from Medicaid preferred drug lists.

BACKGROUND: Oral albuterol has worse efficacy and side effects compared with inhaled albuterol, and thus its use has been discouraged for decades. Drug inclusion or exclusion on formularies have been associated with reductions in low-value care. This study examines dispensing of oral albuterol and inclusion of oral albuterol on state Medicaid drug formularies--Preferred Drug Lists (PDLs). It also evaluates the association between removal of oral albuterol from the PDL and dispensing levels. METHODS: This quasi-experimental study determined oral albuterol inclusion on PDLs and dispensing between 2011 and 2018, using Medicaid program websites and the State Drug Utilization Database. Using a difference-in-differences model, we examine the association between removal of oral albuterol from Arkansas' Medicaid PDL in 2014 and dispensing of this drug through Medicaid, with Iowa as a control state. The outcome measure was the percent of all albuterol prescriptions that were for oral albuterol. RESULTS: A total of 28 state Medicaid PDLs included at least one formulation of oral albuterol in 2018. In 2018, 179,446 oral albuterol prescriptions were dispensed to Medicaid beneficiaries nationally. Medicaid programs paid approximately $3.0 million for oral albuterol prescriptions in 2018. Removal of oral albuterol syrup from the Arkansas PDL in March 2014 was associated with a more rapid decline in dispensing compared with Iowa which maintained this medication on their PDL. CONCLUSIONS: Findings suggest that removal of low-value medications, such as oral albuterol, from PDLs may be one avenue by which state Medicaid programs can reduce wasteful spending while improving guideline-based care.

Impact of Enteral Albuterol on Bradycardic Events After Acute Cervical Spinal Cord Injury.

BACKGROUND: Acute cervical spinal cord injury (ACSCI) is commonly complicated by spinal shock, resulting in hemodynamic instability characterized by bradycardia and hypotension that can have fatal consequences. Current guidelines recommend the use of intravenous beta and dopamine agonists, such as norepinephrine and dopamine, respectively. We sought to determine whether enteral albuterol would be a safe and feasible treatment for bradycardia without an increase in the occurrence of known side effects of albuterol in patients with ACSCI. METHODS: A retrospective review of patients with ACSCI admitted to an intensive care unit at a level I trauma center and treated with enteral albuterol was conducted. Patients were excluded for the following reasons: pure beta blocker use prior to injury, concurrent use of pacemaker, age of less than 18 years, or age more than 75 years. As part of the standard of care, all patients underwent mean arterial pressure (MAP) augmentation to reach a goal of greater than 85 mm Hg during the first 7 days post injury. All eligible patient charts were reviewed for demographic characteristics, daily minimum and maximum heart rate and MAP, and concomitant vasoactive medication use. Bradycardia and tachycardia were defined as heart rate less than 60 beats per minute (bpm) and greater than 100 bpm, respectively. Factors found to be associated with bradycardia on univariate analysis were entered into a multivariable generalized estimating equation analysis to determine factors independently associated with bradycardia during the study period. RESULTS: There were 58 patients with cervical ASCI (age 45 ± 18 years, 76% men) admitted between January 1, 2016, and December 31, 2017, that met the study criteria. The mean time to initiation of albuterol was 1.5 ± 1.7 days post injury, with a duration of 9.3 ± 4.5 days and a mean daily dosage of 7.8 ± 4.5 mg. Bradycardia was observed in 136 of 766 patient days (17%). There were a few episodes of hyperglycemia (1%) and tachycardia (3%), but no episodes of hypokalemia. In a multivariable analysis, female sex (P = 0.006) and American Spinal Cord Injury Association grade A, B, or C (P < 0.001) were associated with a higher risk of developing bradycardia, whereas dosage of albuterol (P = 0.009) and norepinephrine use (P = 0.008) were associated with a lower risk of developing bradycardia. CONCLUSIONS: Albuterol administration in ASCI is a safe and feasible treatment for bradycardia, given that no significant side effects, such as hyperglycemia, hypokalemia, or tachycardia, were observed. The administration of enteral albuterol was well tolerated and, in a dose-dependent manner, associated with a lower occurrence of bradycardia. Further prospective trials for the use of enteral albuterol after SCI are warranted.

Managing respiratory emergencies at school: A county-wide stock inhaler program.

BACKGROUND: A total of 15 states allow schools to manage respiratory emergencies among multiple students by using a single albuterol inhaler (stock inhaler) paired with a disposable holding chamber. OBJECTIVE: Our aim was to evaluate implementation barriers and facilitators, as well as satisfaction with a stock inhaler program across K through12 schools in Pima County, Arizona. METHODS: All public, charter, private, and parochial schools were offered supplies, web-based training, and technical assistance at no cost. The RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance) framework was used to evaluate program implementation. School documentation logs were reviewed, school health personnel were surveyed, and a convenience sample of health personnel were interviewed. Chi-square tests evaluated categoric outcomes and Poisson hurdle regression examined stock inhaler use by school organization type, grade levels served, and type of school health personnel employed. RESULTS: In all, 229 schools (68%) participated, reaching 82% of students in the county. A total of 152 schools (66%) used a stock inhaler, accounting for 1038 events. The mean number of puffs administered was 2.7 (SD = 1.2) per event, and most events (79%) involved students with asthma. Although most events (83.9%) resulted in the student returning to class, 15.6% resulted in students being sent home. Only 6 events resulted in 911 calls, and 5 of these led to an ambulance transport. School health personnel reported high levels of satisfaction, and all schools renewed participation for a second year. Program costs were $156 per school. CONCLUSION: With technical assistance, stock inhaler programs can be feasibly implemented by schools in a wide range of settings, thereby increasing their capacity to safely manage respiratory emergencies.

Emergency Medication Access and Administration in Schools: A Focus on Epinephrine, Albuterol Inhalers, and Glucagon.

Access to emergency medications is a growing concern, particularly regarding the availability, safety, and use of these medications in schools. The purpose of this article is to report results not previously published from a national survey, specifically regarding the emergency use of epinephrine, albuterol inhalers, and glucagon. A nonexperimental, cross-sectional design was utilized for this descriptive study. An online survey was distributed to school nurses in 2015, and data from 6,298 school nurse respondents are presented in the analysis. Findings related to stock and student-specific emergency medication use and storage, epinephrine usage data, and delegation of emergency medication administration to unlicensed assistive personnel are presented in this article. Further development of policies and procedures regarding emergency medication administration in schools is needed. School nurses are a valuable resource for obtaining knowledge in this area and keeping students safe at school.

The ß-Adrenergic Agonist Albuterol Improves Pulmonary Vascular Reserve in Heart Failure With Preserved Ejection Fraction.

RATIONALE: Pulmonary vascular resistance fails to decrease appropriately during exercise in patients with heart failure with preserved ejection fraction (HFpEF). Interventions that enhance pulmonary vasodilation might be beneficial in this cohort but could also worsen left atrial hypertension, exacerbating lung congestion. Intravenous ß-agonists reduce pulmonary vascular resistance but are not suitable for chronic use. OBJECTIVE: We hypothesized that the inhaled ß-adrenergic agonist albuterol would improve pulmonary vasodilation during exercise in patients with HFpEF, without increasing left heart filling pressures. METHODS AND RESULTS: We performed a randomized, double-blind, placebo-controlled trial testing the effects of inhaled albuterol on resting and exercise hemodynamics in subjects with HFpEF using high-fidelity micromanometer catheters and expired gas analysis. The primary end point was pulmonary vascular resistance during exercise. Subjects with HFpEF (n=30) underwent resting and exercise hemodynamic assessment and were then randomized 1:1 to inhaled, nebulized albuterol or placebo. Rest and exercise hemodynamic testing was then repeated. Albuterol improved the primary end point of exercise pulmonary vascular resistance as compared with placebo (-0.6±0.5 versus +0.1±0.7 WU; P=0.003). Albuterol enhanced cardiac output reserve and right ventricular pulmonary artery coupling, reduced right atrial and pulmonary artery pressures, improved pulmonary artery compliance, and enhanced left ventricular transmural distending pressure (all P <0.01), with no increase in pulmonary capillary hydrostatic pressures. CONCLUSIONS: Albuterol improves pulmonary vascular reserve in patients with HFpEF without worsening left heart congestion. Further study is warranted to evaluate the chronic efficacy of ß-agonists in HFpEF and other forms of pulmonary hypertension. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov . Unique identifier: NCT02885636.

A meta-analysis of the influence of ADRB2 genetic polymorphisms on albuterol (salbutamol) therapy in patients with asthma.

AIMS: The associations of 2 nonsynonymous single nucleotide polymorphisms (Arg16Gly and Gln27Glu) in the adrenoceptor ß2 (ADRB2) gene with response after albuterol use are conflicting. We conducted a meta-analysis to examine the cumulative evidence of the effects of these 2 variants on percent forced expiratory volume in 1 second (FEV1.0%) after albuterol use in asthma patients. METHODS: We conducted a comprehensive literature search using MEDLINE, EMBASE, and Cochrane Central Register of Controlled Trials to identify studies examining the association between ADRB2 Arg16Gly and Gln27Glu and FEV1.0% shortly after albuterol administration. The individual study results were combined with weights based on the inverse variance method. This systematic review was registered in the PROSPERO (registration number: CRD42019074554). RESULTS: Among 273 initial studies identified, 7 studies met the inclusion criteria for quantitative evaluation. Results of the overall meta-analysis indicated no statistically significant mean difference of FEV1.0% between genotypes of Arg16Gly and Gln27Glu. In subgroup analyses, significant associations were found for Arg16Gly GG (vs AA) among studies where no methacholine bronchoconstriction was conducted (mean difference, -3.92; 95% confidence interval, -7.29 to -0.54; I2 = 0%), and for Arg16Gly GG (vs GA) among studies that included patients with no comorbidities (mean difference, -1.93; 95% confidence interval, -3.77 to -0.10; I2 = 0%). CONCLUSION: Synthesis of the studies to date shows weak evidence for an association between ADRB2 Arg16Gly and Gln27Glu and FEV1.0% after albuterol use, results of which underscore significant heterogeneity across studies and the need for careful design and sample size considerations.

Inhaled Albuterol Use and Impaired Lactate Clearance in Patients With Sepsis: A Retrospective Cohort Study.

BACKGROUND: Lactate clearance has become important in the management of sepsis. However, factors unrelated to sepsis-induced hyperlactatemia, including ß-2 adrenergic agonists, can interfere with lactate clearance. OBJECTIVES: To investigate the association of inhaled albuterol with lactate clearance in patients with sepsis. METHODS: This was a single-center retrospective cohort study. Adult patients with sepsis diagnosed in the emergency department from May 2015 to May 2016 with initial lactate levels >2 mmol/L and serial lactate measurements 2 to 6 hours apart were included. Patients were divided into 2 groups based on whether they received inhaled albuterol between lactate measurements. The primary end point was lactate clearance of 10%. Secondary end points included intensive care unit (ICU) consultation and in-hospital mortality. A multivariate logistic regression analysis was performed to assess the effect of inhaled albuterol on lactate clearance. RESULTS: Of 269 patients included, 58 (22%) received inhaled albuterol between lactate measurements. This group had a significantly higher prevalence of pulmonary disease and a lower initial lactate compared to those who did not receive inhaled albuterol. They had a significantly lower rate of lactate clearance (45% vs 77%, P < .001); however, ICU consultation (71% vs 57%, P = .066) and in-hospital mortality (19% vs 22%, P = .64) were not significantly different. A multivariate logistic regression analysis adjusting for age, sex, chronic kidney disease, cirrhosis, cancer, septic shock or severe sepsis, and the amount of intravenous fluids received showed that inhaled albuterol was independently associated with impaired lactate clearance (adjusted odds ratio: 0.26, 95% confidence interval: 0.14-0.50, P < .001). CONCLUSIONS: Inhaled albuterol in patients with sepsis was associated with impaired lactate clearance without an increase in ICU consultation or in-hospital mortality. Impaired lactate clearance in patients with sepsis who receive inhaled albuterol should be interpreted with caution.

Predictors for the prescription of albuterol in infants hospitalized for viral bronchiolitis.

INTRODUCTION AND OBJECTIVES: Despite the recommendation against routine use of inhaled bronchodilators in infants with viral bronchiolitis given in the main clinical practice guidelines (CPGs) on viral bronchiolitis, albuterol is widely prescribed to patients with this disease. The aim of this study was to identify predictors of prescription of albuterol in a population of infants hospitalized for viral bronchiolitis. MATERIAL AND METHODS: An analytical cross-sectional study performed during the period from March 2014 to August 2015, in a random sample of patients <2 years old hospitalized in the Fundacion Hospital La Misericordia, a hospital located in Bogota, Colombia. After reviewing the electronic medical records, we collected demographic, clinical, and disease-related information, including prescription of albuterol at any time during the course of hospitalization as the outcome variable. RESULTS: For a total of 1365 study participants, 1042 (76.3%) were prescribed with albuterol therapy. After controlling for potential confounders, it was found that age (OR 1.11; CI 95% 1.08-1.15; p<0.001), and a prolonged length of stay (LOS) (OR 1.93; CI 95% 1.44-2.60; p<0.001) were independent predictors of prescription of albuterol in our sample of patients. By contrast, albuterol prescription was less likely in the post-guideline assessment period (OR 0.41; CI 95% 0.31-0.54; p<0.001), and in infants with RSV isolation (OR 0.71; CI 95% 0.52-0.97; p=0.035). CONCLUSIONS: Albuterol was highly prescribed in our population of inpatients with the disease. The independent predictors of prescription of albuterol in our sample of patients were age, implementation of a CPG on viral bronchiolitis, RSV isolation, and LOS.

Improving efficiency of pediatric emergency asthma treatment by using metered dose inhaler.

Objective: Evidence suggests using metered dose inhaler (MDI) to treat acute asthma in the Emergency Department reduces length of stay, though methods of implementation are lacking. We modified a treatment pathway to recommend use of MDI for mild-moderate asthma in a pediatric ED. Methods: A baseline review assessed discharged patients >2 years with an asthma diagnosis and non-emergent Emergency Severity Index triage assessment (3/4). Our multi-disciplinary team developed an intervention to increase MDI use instead of continuous albuterol (CA) using the following: (1) Redesign the asthma pathway and order set recommending MDI for ESI 3/4 patients. (2) Adding a conditional order for Respiratory Therapists to reassess and repeat MDI until patient reached mild assessment. The primary outcome was the percentage discharged within 3 hours, with a goal of a 10% increase compared to pre-intervention. Balancing measures included admission and revisit rates. Results: 7635 patients met eligibility before pathway change; 12,673 were seen in the subsequent 18 months. For target patients, the percentage discharged in <3 hours increased from 39% to 49%; reduction in median length of stay was 33 minutes. We identified special cause variation for reduction in CA use from 43% to 25%; Revisit rate and length of stay for higher-acuity patients did not change; overall asthma admissions decreased by 8%. Changes were sustained for 18 months. Conclusion: A change to an ED asthma pathway recommending MDI for mild-moderate asthma led to a rapid and sustained decrease in continuous albuterol use, length of stay, and admission rate.

Whole-Genome Sequencing of Pharmacogenetic Drug Response in Racially Diverse Children with Asthma.

RATIONALE: Albuterol, a bronchodilator medication, is the first-line therapy for asthma worldwide. There are significant racial/ethnic differences in albuterol drug response. OBJECTIVES: To identify genetic variants important for bronchodilator drug response (BDR) in racially diverse children. METHODS: We performed the first whole-genome sequencing pharmacogenetics study from 1,441 children with asthma from the tails of the BDR distribution to identify genetic association with BDR. MEASUREMENTS AND MAIN RESULTS: We identified population-specific and shared genetic variants associated with BDR, including genome-wide significant (P < 3.53 × 10-7) and suggestive (P < 7.06 × 10-6) loci near genes previously associated with lung capacity (DNAH5), immunity (NFKB1 and PLCB1), and ß-adrenergic signaling (ADAMTS3 and COX18). Functional analyses of the BDR-associated SNP in NFKB1 revealed potential regulatory function in bronchial smooth muscle cells. The SNP is also an expression quantitative trait locus for a neighboring gene, SLC39A8. The lack of other asthma study populations with BDR and whole-genome sequencing data on minority children makes it impossible to perform replication of our rare variant associations. Minority underrepresentation also poses significant challenges to identify age-matched and population-matched cohorts of sufficient sample size for replication of our common variant findings. CONCLUSIONS: The lack of minority data, despite a collaboration of eight universities and 13 individual laboratories, highlights the urgent need for a dedicated national effort to prioritize diversity in research. Our study expands the understanding of pharmacogenetic analyses in racially/ethnically diverse populations and advances the foundation for precision medicine in at-risk and understudied minority populations.

An occupational exposure limit (OEL) approach to protect home healthcare workers exposed to common nebulized drugs.

Home healthcare is a growing area of employment. Assessment of occupational health risks to home health care workers (HHCWs) is important because in many cases the unique characteristics of the home environment do not facilitate the level of exposure control afforded to caregivers in hospitals and other fixed patient care sites. This assessment is focused on health risks to HHCWs from exposure to pharmaceutical drugs used to treat asthma and other respiratory diseases, which are commonly administered to patients in aerosolized form via nebulizers. We developed risk-based exposure limits for workers in the form of occupational exposure limits (OEL) values for exposure to nebulized forms of the three most common drugs administered by this method: albuterol, ipratropium, and budesonide. The derived OEL for albuterol was 2 µg/day, for ipratropium was 30 µg/day, and for budesonide was 11 µg/day. These OELs were derived based on human effect data and adjusted for pharmacokinetic variability and areas of uncertainty relevant to the underlying data (human and non-human) available for each drug. The resulting OEL values provide an input to the occupational risk assessment process to allow for comparisons to HHCW exposure that will guide risk management and exposure control decisions.

Beta2 -adrenoceptor agonist salbutamol increases protein turnover rates and alters signalling in skeletal muscle after resistance exercise in young men.

KEY POINTS: Animal models have shown that beta2 -adrenoceptor stimulation increases protein synthesis and attenuates breakdown processes in skeletal muscle. Thus, the beta2 -adrenoceptor is a potential target in the treatment of disuse-, disease- and age-related muscle atrophy. In the present study, we show that a few days of oral treatment with the commonly prescribed beta2 -adrenoceptor agonist, salbutamol, increased skeletal muscle protein synthesis and breakdown during the first 5 h after resistance exercise in young men. Salbutamol also counteracted a negative net protein balance in skeletal muscle after resistance exercise. Changes in protein turnover rates induced by salbutamol were associated with protein kinase A-signalling, activation of Akt2 and modulation of mRNA levels of growth-regulating proteins in skeletal muscle. These findings indicate that protein turnover rates can be augmented by beta2 -adrenoceptor agonist treatment during recovery from resistance exercise in humans. ABSTRACT: The effect of beta2 -adrenoceptor stimulation on skeletal muscle protein turnover and intracellular signalling is insufficiently explored in humans, particularly in association with exercise. In a randomized, placebo-controlled, cross-over study investigating 12 trained men, the effects of beta2 -agonist (6 × 4 mg oral salbutamol) on protein turnover rates, intracellular signalling and mRNA response in skeletal muscle were investigated 0.5-5 h after quadriceps resistance exercise. Each trial was preceded by a 4-day lead-in treatment period. Leg protein turnover rates were assessed by infusion of [13 C6 ]-phenylalanine and sampling of arterial and venous blood, as well as vastus lateralis muscle biopsies 0.5 and 5 h after exercise. Furthermore, myofibrillar fractional synthesis rate, intracellular signalling and mRNA response were measured in muscle biopsies. The mean (95% confidence interval) myofibrillar fractional synthesis rate was higher for salbutamol than placebo [0.079 (95% CI, 0.064 to 0.093) vs. 0.066 (95% CI, 0.056 to 0.075%) × h-1 ] (P < 0.05). Mean net leg phenylalanine balance 0.5-5 h after exercise was higher for salbutamol than placebo [3.6 (95% CI, 1.0 to 6.2 nmol) × min-1  × 100 gLeg Lean Mass-1 ] (P < 0.01). Phosphorylation of Akt2, cAMP response element binding protein and PKA substrate 0.5 and 5 h after exercise, as well as phosphorylation of eEF2 5 h after exercise, was higher (P < 0.05) for salbutamol than placebo. Calpain-1, Forkhead box protein O1, myostatin and Smad3 mRNA content was higher (P < 0.01) for salbutamol than placebo 0.5 h after exercise, as well as Forkhead box protein O1 and myostatin mRNA content 5 h after exercise, whereas ActivinRIIB mRNA content was lower (P < 0.01) for salbutamol 5 h after exercise. These observations suggest that beta2 -agonist increases protein turnover rates in skeletal muscle after resistance exercise in humans, with concomitant cAMP/PKA and Akt2 signalling, as well as modulation of mRNA response of growth-regulating proteins.

Development of a novel digital breath-activated inhaler: Initial particle size characterization and clinical testing.

BACKGROUND: Delivery of inhaled respiratory medications have been associated with variable delivery of drug due to errors in device operations and have not been designed to monitor true delivery of medication. A fully digital breath-activated inhaled (DBAI) delivery platform has been developed with integrated firmware and software to address these limitations. METHODS: the device was designed to produce similar aerosol particle output to a marketed albuterol MDI and to the albuterol/ipratropium combination in a soft mist inhaler (SMI). Cascade impactor studies were conducted to demonstrate comparable aerodynamic particle size distribution (APSD) metrics. Efficacy was evaluated by pharmacodynamic studies involving spirometry in two separate protocols with adult subjects having COPD (albuterol DBAI vs. albuterol MDI - Study A, albuterol/ipratropium DBAI single arm - Study B). RESULTS: The total emitted doses (TED) were 81.9 ±â€¯10.3, 109.3 ±â€¯15.0 and 121.9 ±â€¯7.0 µg/actuation for the DBAI, SMI and MDI respectively, and the fine (respirable) particle doses (FPD) were 56.2 ±â€¯6.0, 61.7 ±â€¯5.5 and 79.4 ±â€¯2.7 µg/actuation. MMADs for albuterol sulfate were 1.93 ±â€¯0.11, 1.75 ±â€¯0.19, and 2.65 ±â€¯0.05 µm for the DBAI, Respimat soft mist inhaler (SMI) and MDI respectively. The corresponding GSDs were 1.96 ±â€¯0.16, 2.79 ±â€¯0.25, and 1.48 ±â€¯0.02 µm. The corresponding respirable fractions were 68.7 ±â€¯3.2%, 57.3 ±â€¯10.5%, and 65.2 ±â€¯2.4%. Spirometric study A enrolled 23 subjects (age 64 ±â€¯7.3 years, 39% male, FEV1 45 ±â€¯14% predicted). Study B enrolled 23 subjects (age 65 ±â€¯8.6 years, 43% male, FEV1 47 ±â€¯10% predicted). For Study A, FEV1 at 20 min post-dose improved by 120 (167) mL (p = 0.002) for the DBAI device and 109 (183) mL (p = 0.008) for the MDI device (p = 0.86 for between group differences). For Study B, FEV1 (20 min post-dose) improved by 216 (126) mL (p < 0.001). CONCLUSION: The DBAI generated highly respirable aerosols containing albuterol sulfate that were similar to the MDI and SMI in respirable fraction but lower in dose. Subsequent pharmacodynamic studies delivering albuterol sulfate alone and in combination with ipratropium bromide confirmed similar responses for the DBAI compared with the other inhalers, which could possibly be related to a response ceiling. The DBAI breath-activated capability combined with the ability to monitor actual delivery of medication may improve effectiveness by overcoming patient miscoordination.

Comparison of a rapid albuterol pathway with a standard pathway for the treatment of children with a moderate to severe asthma exacerbation in the emergency department.

OBJECTIVE: The objective of this study was to determine if a rapid albuterol delivery pathway with a breath-enhanced nebulizer can reduce emergency department (ED) length of stay (LOS), while maintaining admission rates and side effects, when compared to a traditional asthma pathway with a standard jet nebulizer. METHODS: Children aged 3-18 presenting to a large urban pediatric ED for asthma were enrolled if they were determined by pediatric asthma score to have a moderate to severe exacerbation. Subjects were randomized to either a standard treatment arm where they received up to 2 continuous albuterol nebulizations, or a rapid albuterol arm where they received up to 4 rapid albuterol treatments with a breath-enhanced nebulizer, depending on severity scoring. The primary endpoint was ED LOS from enrollment until disposition decision. Asthma scores, albuterol dose, side effects, and return visits were also recorded. RESULTS: A total of 50 subjects were enrolled (25 in each arm). The study LOS was shorter in the rapid albuterol group (118 vs. 163 minutes, p = 0.0002). When total ED LOS was analyzed, the difference was no longer statistically significant (192 vs. 203 minutes, p = 0.65). There were no statistically significant differences with respect to admission rates, asthma score changes, side effects, or return visits. CONCLUSION: A rapid albuterol treatment pathway that utilizes a breath-enhanced nebulizer is an effective alternative to traditional pathways that utilize continuous nebulizations for children with moderate to severe asthma exacerbations in the ED.