Treatment of acute asthma

Lung deposition of inhaled once-daily long-acting muscarinic antagonists via standard jet nebulizer or dry powder inhaler, measured using functional respiratory imaging, in patients with chronic obstructive pulmonary disease

Background:

Data for bronchodilator deposition via nebulizers and dry powder inhalers (DPIs) in the respiratory tract of patients with chronic obstructive pulmonary disease (COPD) are limited. We used functional respiratory imaging (FRI) to determine deposition patterns for revefenacin solution via a PARI LC^® Sprint^® nebulizer and tiotropium powder via HandiHaler^® DPI.

Methods:

Ten patients with COPD, of whom 9 had severe airflow obstruction, were selected from FLUIDDA’s database. The study did not enroll patients. Drug deposition in the extrathoracic and intrathoracic regions, including the central and peripheral airways was simulated by FRI. The percentage of delivered dose and central-to-peripheral (C/P) deposition ratio for nebulizer and DPI were evaluated.

Results:

Mean ± standard deviation (SD) age was 64.7 ± 7.1 years, height was 168.8 ± 8.5 cm, and percent predicted forced expiratory volume in 1 s was 40.8 ± 12.3%; 50% of patients were men. At optimal inhalation flow, intrathoracic and peripheral deposition was three-fold higher for revefenacin via nebulizer than tiotropium via HandiHaler (mean ± SD 34.6 ± 8.53% versus 10.9 ± 5.67% and 18.2 ± 4.30% versus 5.8 ± 2.73% of delivered dose, respectively). Similar results were observed for suboptimal flow (mean ± SD percentage of revefenacin versus tiotropium: intrathoracic, 32.1 ± 8.3% versus 15.1 ± 5.9%; peripheral; 16.6 ± 4.1% versus 8.4 ± 2.9%). The C/P deposition ratio for nebulizer was similar to DPI (mean ± SD 0.915 ± 0.241 versus 0.812 ± 0.249 at optimal; 0.947 ± 0.253 versus 0.784 ± 0.219 at suboptimal flow), even though the mass median aerodynamic diameter of revefenacin was higher than tiotropium. C/P deposition ratio for revefenacin decreased after bronchodilation (0.915 ± 0.241 pre-bronchodilation versus 0.799 ± 0.192 post-bronchodilation), suggesting progressively better deposition in the peripheral region, assuming bronchodilation occurred during the nebulization process.

Conclusions:

These results demonstrate more efficient intrathoracic and peripheral deposition for revefenacin via standard jet nebulizer than tiotropium via HandiHaler, with similar C/P deposition ratio in patients with COPD. Nebulizers are an efficient alternative to DPIs for bronchodilator administration in patients with COPD.

The use of ipratropium bromide for treating moderate to severe asthma exacerbations in pediatric patients in an emergency setting: A cost-effectiveness analysis

OBJECTIVES

Although the efficacy of the addition of ipratropium bromide (IB) to short-acting β2-agonists (SABAs) for treating children with moderate to severe asthma exacerbations has been demonstrated, evidence of its cost-effectiveness is scarce. The aim of the present study was to evaluate the cost-effectiveness of treatment with a combination of SABAs and IB compared with SABAs alone for the treatment of children with moderate to severe asthma exacerbations.

METHODS

To achieve the objectives of the study, a decision-analysis model was adapted. Effectiveness parameters were obtained from a systematic review of the literature with meta-analysis. Cost data were obtained from hospital bills and from the national manual of drug prices in Colombia. The study was carried out from the perspective of the national healthcare system in Colombia. The main outcome of the model was avoidance of hospital admission.

RESULTS

In children with moderate to severe asthma exacerbations, the base-case analysis showed that compared to SABAs alone, treatment with a combination of SABAs and IB was associated with lower overall treatment costs (US$126.24 vs. US$170.69 mean cost per patient) and a higher probability of hospital admission avoided (0.7999 vs. 0.7100), thus leading to dominance. For children with severe asthma exacerbations, these values were US$132.99 versus US$170.69 and 0.7883 versus 0.7100, respectively.

CONCLUSIONS

In Colombia, when compared to therapy with SABAs alone, therapy with a combination of SABAs and IB for treating pediatric patients with moderate to severe asthma exacerbations involves a lower probability of hospital admission at lower treatment costs.

Addition of intravenous beta(2)-agonists to inhaled beta(2)-agonists for acute asthma

BACKGROUND

Inhaled beta-agonist therapy is central to the management of acute asthma. This review evaluates the benefit of an additional use of intravenous beta(2)-agonist agents.

OBJECTIVES

To determine the benefit of adding intravenous (IV) beta(2)-agonists to inhaled beta(2)-agonist therapy for acute asthma treated in the emergency department.

SEARCH METHODS

Randomised controlled trials (RCTs) were identified using the Cochrane Airways Group Register which is a compilation of systematic searches of MEDLINE, EMBASE, CINAHL, and CENTRAL as well as handsearching of 20 respiratory journals. Bibliographies from included studies and known reviews were also searched. Primary authors and content experts were contacted to identify eligible studies. The search was performed in September 2012.

SELECTION CRITERIA

Only RCTs were considered for inclusion. Studies were included if patients presented to the emergency department with acute asthma and were treated with IV beta(2)-agonists with inhaled beta(2)-agonist therapy and existing standard treatments versus inhaled beta(2)-agonists and existing standard treatments.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and confirmed their findings with corresponding authors of trials. We obtained missing data from authors or calculated from data present in the papers. We used fixed-effect model for odds ratios (OR) and for mean differences (MD) we used both fixed-effect and random-effects models and reported 95% confidence intervals (CI).

MAIN RESULTS

From 109 potentially relevant studies only three (104 patients) met our inclusion criteria: Bogie 2007 (46 children), Browne 1997 (29 children) and Nowak 2010 (29 adults). Bogie 2007 investigated the addition of intravenous terbutaline to high dose nebulised albuterol in children with acute severe asthma, requiring intensive care unit (ICU) admission. Browne 1997 investigated the benefit of adding intravenous salbutamol to inhaled salbutamol in children with acute severe asthma in the emergency department. Nowak 2010 investigated addition of IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids) among adults, and was reported as a conference abstract only.There was no significant advantage (OR 0.29; 95%CI 0.06 to 1.38, one trial, 29 adults) for adding IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids) with regard to hospitalisation rates.Various outcome indicators for the length of stay were reported among the trials. Browne 1997 reported a significantly shorter recovery time (in terms of cessation of 30 minute salbutamol) for children in the IV salbutamol with inhaled salbutamol group (four hours) versus the 11.1 hours for the inhaled salbutamol group (P = 0.03). Time to cessation of hourly nebuliser was also significantly shorter (P = 0.02) for the IV plus inhaled salbutamol group (11.5 hours versus 21.2 hours), and they were ready for emergency patient discharge on average 9.7 hours earlier than the inhaled salbutamol group (P < 0.05). In a paediatric ICU study Bogie 2007 reported no significant advantage in length of paediatric ICU admission (hours) for adding IV terbutaline to nebulised albuterol (MD -12.95, 95% CI: -38.74, 12.84).Browne 1997 reported there were only six out of 14 children with a pulmonary index score above six in the IV plus inhaled salbutamol group at two hours compared with 14 of the 15 in the inhaled salbutamol group (P = 0.02)In Browne 1997 there was a higher proportion of tremor in the IV plus inhaled salbutamol group than in the inhaled salbutamol group (P < 0.02). Nowak 2010 did not report any statistically significant adverse effects associated with adding IV bedoradrine to standard care (nebulised albuterol, ipratropium and oral corticosteroids). Troponin levels were elevated in three children in the IV terbutaline + nebulised albuterol group at 12 and 24 hours in Bogie 2007

AUTHORS' CONCLUSIONS

There is very limited evidence from one study (Browne 1997) to support the use of IV beta(2)-agonists in children with severe acute asthma with respect to shorter recovery time, and similarly there is limited evidence (again from one study Browne 1997) suggesting benefit with regard to pulmonary index scores; however this advantage needs to be considered carefully in relation to the increased side effects associated with IV beta(2)-agonists. We identified no significant benefits for adults with severe acute asthma. Until more, adequately powered, high quality clinical trials in this area are conducted it is not possible to form a robust evaluation of the addition of IV beta(2)-agonists in children or adults with severe acute asthma.

Intravenous beta(2)-agonists versus intravenous aminophylline for acute asthma

BACKGROUND

Inhaled beta(2)-agonist therapy is central to the management of acute asthma. For rapid bronchodilation in severe cases, penetration of inhaled drug to the affected small conducting airway may be impeded, and the intravenous (IV) rather than inhaled administration of bronchodilators may provide an earlier response. IV beta(2)-agonist agents and IV aminophylline may also be considered as additional interventions in this setting and this review compares IV beta-agonist agents and IV aminophylline in the treatment of people with acute asthma.

OBJECTIVES

To compare the benefit of IV beta(2)-agonists versus IV aminophylline for acute asthma treated in the emergency department and in patients admitted to hospital with acute severe asthma.

SEARCH METHODS

Randomised controlled trials (RCTs) were identified using the Cochrane Airways Group Register, which is compiled from systematic searches of bibliographic databases as well as handsearching of respiratory journals and conference abstracts. The latest search was run in September 2012. We searched bibliographies from included studies and known reviews were also searched. Primary authors and content experts were contacted to identify eligible studies.

SELECTION CRITERIA

We included RCTs of patients who presented to the emergency department with acute asthma, and patients admitted to hospital with acute severe asthma, and were treated with IV beta(2)-agonists versus IV aminophylline. Two review authors independently selected potentially relevant articles and selected articles for inclusion. Methodological quality was independently assessed using two scoring systems and two review authors.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors. Missing data were obtained from authors or calculated from data present in the papers. Trials were combined using a random-effects model for odds ratios (OR) or mean differences (MD) and reported with 95% confidence intervals (95% CI).

MAIN RESULTS

Eleven studies met our inclusion criteria and in total they included 350 patients. However, opportunities to combine these studies in meta-analyses were limited by the variations in the range of outcomes reported in the trials.Length of stayTwo studies reported length of stay. They were both paediatric trials (with one in paediatric intensive care unit), and there was no significant difference between the two groups (MD 23.19 hours; 95% CI -2.40 to 48.77 hours; 2 studies; N = 73). Individual separate MD analyses for the two studies also indicated no significant difference between the aminophylline and beta(2)-agonist on this outcome. However, this finding should be interpreted with caution owing to the small number of trials and participants the analysis.Pulmonary functionThere were no significant differences in the sequential or summative pulmonary function demonstrated across the studies.Heart rateData for serial heart rates were reported in three studies at various points from 15 to 60 minutes and in each case there were no significant differences between people in the IV aminophylline or beta(2)-agonist groups. The difference between the two groups with respect to final heart rate was statistically significant (MD 10.00; 95% CI 0.99 to 19.01), although these data are from a single, small study and should be interpreted with caution.Adverse effectsThe analyses for giddiness (OR 59.22; 95% CI 2.80 to 1253.05; 1 study; N = 30), nausea/vomiting (where reported as a combined outcome) (OR 14.18; 95% CI 1.62 to 124.52; 2 studies; N = 96) and nausea (OR 6.53; 95% CI 1.60 to 26.72; 2 studies; N = 49) all significantly favoured beta(2)-agonists. In view of the very small number of studies and number of patients contributing to these analyses these results should be interpreted with caution. A closely related review considering the possible benefits of adding IV aminophylline to beta-agonists in adults with acute asthma also indicates a higher incidence of adverse effects associated with IV aminophylline.

AUTHORS' CONCLUSIONS

In the included RCTs there was no consistent evidence favouring either IV beta(2)-agonists or IV aminophylline for patients with acute asthma. The opportunity to draw clear conclusions is limited by the heterogeneity of outcomes evaluated and the small sample sizes in the included studies. It is recommended that these data should be viewed carefully alongside the conclusions from separate Cochrane reviews comparing IV beta(2)-agonists plus inhaled beta(2)-agonists versus inhaled beta(2)-agonists alone and IV aminophylline plus inhaled beta(2)-agonists versus inhaled beta(2)-agonists alone.

Early use of inhaled corticosteroids in the emergency department treatment of acute asthma

BACKGROUND

Systemic corticosteroid therapy is central to the management of acute asthma. The use of inhaled corticosteroids (ICS) may also be beneficial in this setting.

OBJECTIVES

To determine the benefit of ICS for the treatment of patients with acute asthma managed in the emergency department (ED).

SEARCH METHODS

We identified controlled clinical trials from the Cochrane Airways Group specialised register of controlled trials. Bibliographies from included studies, known reviews, and texts also were searched. The latest search was September 2012.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) and quasi-RCTs. Studies were included if patients presented to the ED or its equivalent with acute asthma, and were treated with ICS or placebo, in addition to standard therapy. Two review authors independently selected potentially relevant articles, and then independently selected articles for inclusion. Methodological quality was independently assessed by two review authors. There were three different types of studies that were included in this review: 1) studies comparing ICS vs. placebo, with no systemic corticosteroids given to either treatment group, 2) studies comparing ICS vs. placebo, with systemic corticosteroids given to both treatment groups, and 3) studies comparing ICS alone versus systemic corticosteroids. For the analysis, the first two types of studies were included as separate subgroups in the primary analysis (ICS vs. placebo), while the third type of study was included in the secondary analysis (ICS vs. systemic corticosteroid).

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors if the authors were unable to verify the validity of extracted information. Missing data were obtained from the authors or calculated from other data presented in the paper. Where appropriate, individual and pooled dichotomous outcomes were reported as odds ratios (OR) with 95% confidence intervals (CIs). Where appropriate, individual and pooled continuous outcomes were reported as mean differences (MD) or standardized mean differences (SMD) with 95% CIs. The primary analysis employed a fixed-effect model and a random-effects model was used for sensitivity analysis. Heterogeneity is reported using I-squared (I(2)) statistics.

MAIN RESULTS

Twenty trials were selected for inclusion in the primary analysis (13 paediatric, seven adult), with a total number of 1403 patients. Patients treated with ICS were less likely to be admitted to hospital (OR 0.44; 95% CI 0.31 to 0.62; 12 studies; 960 patients) and heterogeneity (I(2) = 27%) was modest. This represents a reduction from 32 to 17 hospital admissions per 100 patients treated with ICS in comparison with placebo. Subgroup analysis of hospital admissions based on concomitant systemic corticosteroid use revealed that both subgroups indicated benefit from ICS in reducing hospital admissions (ICS and systemic corticosteroid versus systemic corticosteroid: OR 0.54; 95% CI 0.36 to 0.81; 5 studies; N = 433; ICS versus placebo: OR 0.27; 95% CI 0.14 to 0.52; 7 studies; N = 527). However, there was moderate heterogeneity in the subgroup using ICS in addition to systemic steroids (I(2) = 52%). Patients receiving ICS demonstrated small, significant improvements in peak expiratory flow (PEF: MD 7%; 95% CI 3% to 11%) and forced expiratory volume in one second (FEV(1): MD 6%; 95% CI 2% to 10%) at three to four hours post treatment). Only a small number of studies reported these outcomes such that they could be included in the meta-analysis and most of the studies in this comparison did not administer systemic corticosteroids to either treatment group. There was no evidence of significant adverse effects from ICS treatment with regard to tremor or nausea and vomiting. In the secondary analysis of studies comparing ICS alone versus systemic corticosteroid alone, heterogeneity among the studies complicated pooling of data or drawing reliable conclusions.

AUTHORS' CONCLUSIONS

ICS therapy reduces hospital admissions in patients with acute asthma who are not treated with oral or intravenous corticosteroids. They may also reduce admissions when they are used in addition to systemic corticosteroids; however, the most recent evidence is conflicting. There is insufficient evidence that ICS therapy results in clinically important changes in pulmonary function or clinical scores when used in acute asthma in addition to systemic corticosteroids. Also, there is insufficient evidence that ICS therapy can be used in place of systemic corticosteroid therapy when treating acute asthma. Further research is needed to clarify the most appropriate drug dosage and delivery device, and to define which patients are most likely to benefit from ICS therapy. Use of similar measures and reporting methods of lung function, and a common, validated, clinical score would be helpful in future versions of this meta-analysis.

Progress in the management of childhood asthma

Asthma has become the most common chronic disease in childhood. Significant advances in epidemiological research as well as in therapy of pediatric asthma have been made over the past 2 decades. In this review, we look at certain aspects therapy of childhood asthma, both in the past and present. Literature review on allergen avoidance (including mites, cockroach and cat), intensive therapy with β(2)-agonists in acute asthma (administering via continuous nebulization and intravenous routes), a revisit of theophylline use and its action, the use of inhaled corticosteroids in various phases of childhood asthma and sublingual immunotherapy in asthma are examined. Recent facts and dilemmas of these treatments are identified along with expression of our opinions, particularly on points of childhood asthma in the Asia-Pacific, are made in this review.

Review article: management of acute severe and near-fatal asthma

Despite a decline in the Australian overall asthma mortality, near-fatal/critical asthma continues to be a significant management issue for emergency physicians and intensivists. Near-fatal asthma is a unique subtype of asthma, with a variety of clinical presentations, requiring rapid and aggressive intervention. The pharmacological and non-pharmacological management of near-fatal asthma remains very complex. The present review discusses recent advances and evidence for current available strategies targeting this time critical emergency.

[Bronchodilators via metered-dose inhaler with spacer in the pediatric emergency department: what is the dosage?]

INTRODUCTION

Bronchodilators administrated through a metered-dose inhaler (MDI) with spacer are as effective as nebulizers in the treatment of acute asthma exacerbations in childhood. However, consensus is lacking on the most suitable dosage.

OBJECTIVE

To assess the effectiveness of distinct salbutamol and terbutaline doses delivered via an MDI with spacer for the treatment of acute asthma in the pediatric emergency department.

METHODS

This was a prospective, double-blind randomized study. All consecutive children (n = 324) between 2 and 14 years of age with acute asthma exacerbations treated in the pediatric emergency department between October 1 and November 30, 2004, were included. Two treatment groups were established: one group received a number of puffs equivalent to half the child's weight (1 puff of salbutamol = 100 microg and 1 puff of terbutaline = 250 microg) and the other group received a number of puffs equivalent to one-third of the child's weight.

RESULTS

Three hundred twenty-four episodes were studied; there were 164 children in the first group and 160 in the second. There were no significant differences between the two groups in the mean (6 SD) age (58.34 +/- 34.72 vs 66.04 +/- 36.45 months), arterial oxygen saturation (95.49 +/- 1.93 vs 95.56 +/- 1.97) or pulmonary score (4.04 +/- 1.55 vs 3.97 +/- 1.51) at recruitment and after treatment in the emergency department (arterial oxygen saturation [96.34 +/- 1.60 vs 96.18 +/- 1.77], pulmonary score [1.87 +/- 1.33 vs 1.64 +/- 1.31]). The number of doses administered (2.17 +/- 0.91 vs 2.24 +/- 1.00) and the hospitalization rate (8.56 % vs 6.87 %) were also similar in both groups.

CONCLUSIONS

The distinct bronchodilator doses administered via an MDI with spacer showed similar effectiveness. These findings should contribute to a reevaluation of the use of high doses of bronchodilators, at least in most acute asthma exacerbations in children.

Monitoring bronchodilators with direct injection

A procedure was developed for the determination of caffeine and theophylline using a C18 column (5 microm, 250 mm x 4.6 mm) and micellar liquid chromatography using hybrid mobile phases containing sodium dodecyl sulfate (SDS) and propanol, butanol or pentanol as modifiers. Detection was performed with a variable wavelength UV-vis detector at 272 nm. After the application of an interpretative strategy for the selection of the optimimum mobile phase, caffeine and theophylline can be resolved and determined in serum samples by direct injection, using a mobile phase made up of 50 mM SDS-2.5% (v/v) propanol-10 mM KH2PO4, pH 7, with an analysis time below 5 min. Calibration was linear in the range 0.05 to 50 microg mL(-1) with r > 0.999. The statistical evaluation of the method was examined by performing intra-day (n = 6) and inter-day calibration (n = 7) and was found to be satisfactory, with highly accurate and precise results. The proposed method was suitably validated and applied to the determination of caffeine and theophylline in serum samples of patients treated with bronchodilators.

[Treatment of exacerbation of asthma: what are today's issues?]

During past decades, major progress has been accomplished in the management of acute asthma. Most recent recommendations include evidence-based rationale. The improved quality of clinical guidelines makes them efficient models for medical education. The pediatric pharmacopoeia provides a great variety of choices of drugs as well as for asthma medical devices. These innovations dramatically facilitated the medical management of asthmatic children, but they did not solve all problems. Physicians now use higher doses of salbutamol, but the early prescription of systemic glucocorticoids for moderate exacerbation of asthma is still underused, given the most recent clinical guidelines and meta-analysis. Furthermore, repeated emergency department visits to the wards and lack of primary care physician should systematically be appraised when evaluating severity, as they are both major risk factors for severe exacerbations, even though they are not considered in acute asthma severity scores. Finally, initiating (or reinforcing) patient education at the time of exacerbation also presents important challenges, as emergency visits are a favorable moment to commence the therapeutic education of the child and his family. Indeed, framing the controller medications and educating families about how to manage the disease and to improve their domestic environment are the genuine tools available for the prevention of asthma exacerbations, and particularly those most severe.

Salbutamol via metered-dose inhaler with spacer versus nebulization for acute treatment of pediatric asthma in the emergency department

OBJECTIVES

To assess the effectiveness of salbutamol delivered via a metered-dose inhaler with spacer versus a nebulizer for acute asthma treatment in the pediatric emergency department.

METHODS

All consecutive children younger than 14 years old who required treatment of acute asthma exacerbation in the emergency department during May 2002 (prospective cohort, n = 321) and May 2001(retrospective cohort, n = 259) were included. Inhaled salbutamol was administered by metered-dose inhaler with a spacer (and a face mask in children younger than 2 years old) in the prospective cohort and by nebulizer in the retrospective cohort.

RESULTS

There were no significant differences between the two cohorts in the mean (+/-SD) age (44.50 +/- 38.64 vs. 48.37 +/- 43.55 months) and asthma treatment, arterial oxygen saturation (96.34 +/- 2.12% vs. 96.19 +/- 6.32%), and heart rate (123.71 +/- 23.63 vs. 129.41 +/- 34.55 beats/min) before emergency department consultation. The number of doses of inhaled bronchodilators was also similar (1.42 +/- 1.01 vs. 1.45 +/- 0.98) as well as the number of children that required a stay in the observation unit, admission to the hospital, or returned for medical care. The overall mean length of stay in the emergency department was slightly shorter in the prospective cohort (82 +/- 48 vs. 89 +/- 52 minutes).

CONCLUSIONS

The administration of bronchodilators using a metered-dose inhaler with spacer is an effective alternative to nebulizers for the treatment of children with acute asthma exacerbations in the emergency department.

Treating exacerbations of asthma in children: the role of systemic corticosteroids

OBJECTIVE

To review the use of systemic corticosteroids to treat recurrent, acute asthma episodes in children, with a focus on the role of oral corticosteroids.

METHODS

A comprehensive review of the literature was performed using the Medline database (January 1966-October 2002) and the Embase database (January 1980-August 2002).

RESULTS

The significant findings of 17 selected, controlled clinical trials of oral corticosteroids (OCSs) for acute exacerbations of asthma in children, compared with placebo or with other formulations of corticosteroids, can be summarized as follows: 1) OCSs are effective for the outpatient treatment of acute asthma, 2) pulmonary function tests may not be the best means of assessing the efficacy of OCSs for acute asthma, 3) early administration of OCSs for acute asthma reduces hospitalizations, 4) the critical factor for a positive outcome is early administration of the corticosteroid, and 5) OCSs are preferred for the outpatient treatment of acute asthma.

CONCLUSIONS

Early treatment of acute asthma symptoms with OCSs in children with a pattern of recurrent acute asthma may decrease the severity of acute asthma episodes and reduce the likelihood of subsequent relapses. Attention should be given to identifying these children and standardizing a treatment approach based on accepted, consistent definitions of what constitutes an asthma exacerbation and recurrence. A suggested protocol is described.

Early use of inhaled corticosteroids in the emergency department treatment of acute asthma

BACKGROUND

Systemic corticosteroid therapy is central to the management of acute asthma The use of inhaled corticosteroids may also be beneficial in this setting.

OBJECTIVES

To determine the benefit of inhaled corticosteroids for the treatment of patients with acute asthma managed in the emergency department (ED).

SEARCH STRATEGY

Randomised controlled trials (RCTs) were identified from the Cochrane Airways Review Group register. Bibliographies from included studies, known reviews, and texts also were searched. The search is considered updated to February of 2003.

SELECTION CRITERIA

Only RCTs or quasi-randomised trials were eligible for inclusion. Studies were included if patients presented with acute asthma to the ED or its equivalent, and were treated with inhaled corticosteroids or placebo, in addition to standard therapy. Two reviewers independently selected potentially relevant articles, and then independently selected articles for inclusion. Methodological quality was independently assessed by two reviewers.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers if the authors were unable to verify the validity of extracted information. Missing data were obtained from the authors or calculated from other data presented in the paper.

MAIN RESULTS

Eight trials were selected for inclusion, but data were not available for one of them. In the seven usable trials, (4 adult, 3 paediatric), a total of 376 patients were studied (191 with inhaled corticosteroids, 185 without). Patients treated with inhaled corticosteroids were less likely to be admitted to hospital (OR: 0.30; 95% CI: 0.16, 0.57). This benefit was evident in the subgroup of patients not receiving concomitant systemic steroids (OR 0.21; 95% CI: 0.08, 0.53). Patients receiving concomitant systemic steroids showed a similar, but non-significant, trend towards reduced admissions compared to placebo treatment (OR 0.45; 95% CI: 0.18, 1.12). Patients receiving inhaled corticosteroids also demonstrated small, significant improvements in peak expiratory flows (PEFR WMD: 8%; 95% CI: 3, 13 %) and forced expiratory volumes (FEV1 WMD: 5%; 95% CI: 0.4, 10 %). The treatment was well tolerated, with few reported adverse side effects. A secondary analysis compared inhaled corticosteroids alone vs systemic steroids alone; in the four trials included, there was significant heterogeneity between the study results for admission rates which precluded meaningful pooling of the study results.

REVIEWER'S CONCLUSIONS

Inhaled steroids reduced admission rates in patients with acute asthma, but it is unclear if there is a benefit of inhaled corticosteroids when used in addition to systemic corticosteroids. There is insufficient evidence that inhaled corticosteroids result in clinically important changes in pulmonary function or clinical scores when used in acute asthma. Similarly, there is insufficient evidence that inhaled corticosteroids alone are as effective as systemic steroids. Further research is needed to clarify if there is a benefit of inhaled corticosteroids when used in addition to systemic steroids.

A proposal for a practical treatment guideline designed for the initial two-hours of the management of patients with acute severe asthma and COPD using the principles of evidence-based medicine

We have proposed a clinical treatment guideline for the management of acute, severe asthma and chronic obstructive pulmonarydisease (COPD) using the principles of evidence-based medicine. The content is based upon practical clinical issues in need of consensus. A previous study has shown that this particular area is in serious need of quality control. Based on a strict 2 h time schedule with a unified treatment plan for both asthma and COPD, it is possible to secure for the patients a well-documented medical therapy promoting decision-making and clarification of the patient within this time limit. A summary of the statements is presented in a one-page, user-friendly format in order to cope with the clinician's need of having access to published evidence quickly and easily. A website (www.phanareth.dk or a website provided by Respiratory Medicine) has been established providing regular updates. A strategy for the implementation and the evaluation process has been planned after the publication of this paper. We believe this approach to be an important step towards an increase in the quality of guidelines and also a tool to make "guideline writers" aware of the responsibility of making their recommendations work.

The effectiveness of IV beta-agonists in treating patients with acute asthma in the emergency department: a meta-analysis

OBJECTIVES

To determine the benefit of IV beta(2)-agonists for severe acute asthma treated in the emergency department (ED).

METHODS

Randomized controlled trials were identified using EMBASE, MEDLINE, and CINAHL; the Cochrane Airways Review Group database; hand searching; bibliographies; pharmaceutical companies; and author contact. Studies where IV beta(2)-agonists were compared to placebo and/or existing standards of care were considered. Where appropriate, trials were combined using odds ratios (ORs) or weighted mean differences with 95% confidence intervals (CIs).

RESULTS

From 746 identified references, 55 potentially relevant articles were identified and 15 articles were included. All trials were performed outside North America and were published prior to 1997. Three main treatment strategies were reviewed: strategy 1 (three articles), IV beta(2)-agonists with inhaled beta(2)-agonists vs inhaled beta(2)-agonists; strategy 2 (six articles), IV beta(2)-agonists alone vs inhaled beta(2)-agonists; and strategy 3 (six articles), IV beta(2)-agonists vs IV methylxanthines. Compared to all treatments, IV beta(2)-agonist use did not lead to clinical or statistical significant differences in vital signs, pulmonary functions, laboratory measures, adverse effects, or clinical success. Although statistically nonsignificant, seven methodologically strong studies demonstrated that peak expiratory flows and heart rates were unchanged following beta(2)-agonist use compared to all other treatments at 60 min (8.3 L/min [95% CI, 17.6 to 34.2] and 3.65 beats/min [95% CI, 2.9 to 10.2], respectively), with an increased risk of adverse effects (OR, 1.98; 95% CI, 0.5 to 8.2).

CONCLUSIONS

Evidence is lacking to support the use of IV beta(2)-agonists in ED patients with severe acute asthma. Moreover, the clinical benefit appears questionable, while the potential clinical risks are obvious. The only recommendations for IV beta-(2)agonist use should be in those patients in whom inhaled therapy is not feasible, or in the context of a controlled clinical trial comparing IV beta(2)-agonists with standard care vs standard care alone.

Intravenous beta2-agonists for acute asthma in the emergency department

BACKGROUND

Inhaled beta-agonist therapy is central to the management of acute asthma. The use of intravenous beta-agonist agents may also be beneficial in this setting.

OBJECTIVES

To determine the benefit of intravenous (IV) beta2-agonists for severe acute asthma treated in the emergency department.

SEARCH STRATEGY

Randomised controlled trials (RCT) were identified using the Cochrane Airways Group Register which is a compilation of systematic searches of MEDLINE, EMBASE, CINAHL, and CENTRAL as well as hand searching of 20 respiratory journals. Bibliographies from included studies and known reviews were also searched. Primary authors and content experts were contacted to identify eligible studies.

SELECTION CRITERIA

Only RCTs were considered for inclusion. Studies were included if patients presented to the emergency department with acute asthma and were treated with IV selective or nonselective beta2-agonists versus placebo, inhaled beta2-agonists, or other standard of care. Pulmonary function, vital signs, arterial gasses, adverse effects, and/or clinical success could be reported as outcome measures. Two reviewers independently selected potentially relevant articles and selected articles for inclusion. Methodological quality was independently assessed using two scoring systems and two reviewers.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers, and confirmed with corresponding authors. Missing data were obtained from authors or calculated from data present in the papers. Trials were combined using a random effects model for odds ratios (OR) or weighted mean differences (WMD) and reported with 95% confidence intervals (95% CI).

MAIN RESULTS

From 746 identified references, 55 potentially relevant articles were identified and 15 were included. The trials included 584 patients. Overall, selective IV beta2-agonist use conferred no advantage over the comparator regimes. For example, it was associated with a lower PEFR after 60 mins compared to inhaled beta2-agonist, although the difference was not statistically significant (-24.7 l/min; 95%CI 2.9, -52.3). There was no difference in heart rate (4.5 bpm; 95% CI -4.9, 14.0). In the well performed blinded studies there was no difference in autonomic side effects between treatments (Odds Ratio 2.2 (95%CI 0.9, 5.7).

REVIEWER'S CONCLUSIONS

There is no evidence to support the use of IV beta2-agonists in patients with severe acute asthma. These drugs should be given by inhalation. No subgroups were identified in which the IV route should be considered.

Body weight characteristics of subjects on asthma medication

OBJECTIVE

Weight gain is a frequently documented side effect after long-term anti-inflammatory treatment with systemic corticosteroid drugs in patients with asthma. In recent years new types of inhaled corticosteroids have been introduced, which act locally and are more rapidly bio-transformed. Even such corticosteroids may have a detectable, clinically relevant systemic side effect on weight. The aim of this study is to investigate if there is any relationship between body weight and asthma medication.

DESIGN

The relationship between asthma medication and body weight was analysed in two combined randomized samples of the adult Swedish population 16-60 y of age (n = 17,912). Multivariate logistic regression analyses were carried out to obtain estimates for (1) body mass index (BMI) indicating 'obesity' (BMI > 29.9 kg/m2) in men and women controlling for self-reported asthma medication, and (2) self-reported asthma medication controlling for BMI. In both cases we furthermore controlled for interview period, age, Swedish region, smoking habits, physical activities and level of education.

RESULTS

We found no significantly higher odds for obesity in men (OR = 1.21 (0.55-2.64) or women (OR = 1.97 (0.89-4.38) on asthma medication compared to men and women with pharmacologically untreated asthma even after adjustment for smoking habits, physical activities, level of education and other related co-variables. However, we found significant positive associations between obesity and interview period, age and former smoking and inverse significant relationships with the degree of physical activity. We also found significantly higher adjusted odds for asthma, indicated by self-reported asthma medication, in women (OR = 2.74 (1.91-3.91)) but not in men (OR = 1.57 (0.96-2.56)) with BMI indicating 'obesity'.

CONCLUSION

There is no strong evidence to suggest that modern pharmacological asthma treatment may contribute much to the development of obesity in either men or women on asthma medication. Adjustment for smoking habits, physical activities, level of education and other related co-variables have minor effects on these relationships. Obesity may still be an independent risk factor for asthma since we observed significantly higher odds for self-reported asthma medication in women and an almost significant relationship in men even after control for BMI and other related co-variables.

High-dose albuterol by metered-dose inhaler plus a spacer device versus nebulization in preschool children with recurrent wheezing: A double-blind, randomized equivalence trial

Inhaled albuterol is the most frequently used bronchodilator for acute wheezing, and nebulization is the standard mode of delivery in hospital setting. However, recent guidelines consider spacer devices as an easier to use, and cost-saving alternative and recommend the high-dose metered-dose inhaler bronchodilator.

OBJECTIVE

To demonstrate clinical equivalence between a spacer device and a nebulizer for albuterol administration.

DESIGN

Randomized, double-blind, parallel group equivalence trial.

SETTING

Pediatric emergency wards at 2 tertiary teaching hospitals.

PATIENTS

Sixty-four 12- to 60-month-old children with acute recurrent wheezing (32 per group).

INTERVENTIONS

Albuterol was administered through the spacer device (50 microg/kg) or through the nebulizer (150 microg/kg) and repeated 3 times at 20-minute intervals. Parents completed a questionnaire.

OUTCOME MEASURES

Pulmonary index, hospitalization, ease of use, acceptability, and pulse oximetry saturation.

RESULTS

The 90% confidence interval of the difference between treatment groups for the median absolute changes in pulmonary index values between T0 and T60 was [-1; +1] and was included in the equivalence interval [-1.5; +1.5]. Clinical improvement increased with time. Less than 10% of the children (3 in each group) required hospitalization (2 in each group attributable to treatment failure). Parents considered administration of albuterol using the spacer device easier (94%) and better accepted by their children (62%).

CONCLUSIONS

The efficacy of albuterol administered using the spacer device was equivalent to that of the nebulizer. Given its high tolerance, repeated 50-microg/kg doses of albuterol administered through the spacer device should be considered in hospital emergency departments as first-line therapy for wheezing.

Bronchial asthma: information on phytotherapy with essential fatty acids. Interactions between essential fatty acids and steroid hormones

The pharmacological treatment of bronchial asthma is based on the inhalation of bronchodilative beta2 agonists and steroid hormones. In view of the therapeutic successes obtained with evening primrose oil in the treatment of neurodermatitis in children, the question arises whether this phytotherapeutic substitution therapy could at least partly replace symptomatic pharmacotherapy in bronchial asthma. It is shown that this will only be successful if one dispenses with the anti-inflammatory effect of the treatment with steroid hormones.

Magnesium sulfate for treating exacerbations of acute asthma in the emergency department

BACKGROUND

Treatment of acute asthma is based on rapid reversal of bronchospasm and arresting airway inflammation. There is some evidence that intravenous magnesium can provide additional bronchodilation when given in conjunction with standard bronchodilating agents and corticosteroids. No systematic review of this literature has been completed on this topic.

OBJECTIVES

To examine the effect of additional intravenous magnesium sulfate in patients with acute asthma managed in the emergency department.

SEARCH STRATEGY

Randomised controlled trials were identified from the Cochrane Airways Review Group register. Bibliographies from included studies, known reviews and texts were searched. Primary authors and content experts were contacted.

SELECTION CRITERIA

Randomised controlled trials or quasi-randomised trials were eligible for inclusion. Studies were included if patients presented with acute asthma and were treated with IV magnesium sulfate vs placebo.

DATA COLLECTION AND ANALYSIS

Data were extracted and methodological quality was assessed independently by two reviewers. Missing data were obtained from authors.

MAIN RESULTS

Seven trials were included (5 adult, 2 pediatric). A total of 665 patients were involved. Patients receiving magnesium sulfate demonstrated non-significant improvements in peak expiratory flow rates when all studies were pooled (weighted mean difference: 29.4 L/min; 95% confidence interval: -3.4 to 62). In studies of people with severe acute asthma, peak expiratory flow rate improved by 52.3 L/min (95% confidence interval: 27 to 77.5). The forced expiratory volume in one second also improved by 9.8 % predicted (95% confidence interval: 3.8 to 15.8). Overall, admission to hospital was not reduced, odds ratio: 0.31 (95% confidence interval: 0.09 to 1.02). In the severe subgroup, admissions were reduced in those receiving magnesium sulfate (odds ratio: 0.10, 95% confidence interval: 0.04 to 0.27). No clinically important changes in vital signs or adverse side effects were reported.

REVIEWER'S CONCLUSIONS

Current evidence does not support routine use of intravenous magnesium sulfate in all patients with acute asthma presenting to the emergency department. Magnesium sulfate appears to be safe and beneficial in patients who present with severe acute asthma.

A meta-analysis of the effects of ipratropium bromide in adults with acute asthma

PURPOSE

To review the literature to determine whether inhaled ipratropium bromide provides additive benefits to adults with acute asthma who are being treated with beta-agonists in an emergency department.

SUBJECTS AND METHODS

English-language studies, both published (1978 to 1999) and unpublished, were retrieved using Medline, Science Citation Index, Current Contents, bibliographic reviews of primary research, review articles, consultation with experts, and the register of Medical Editors' Trial Amnesty. Only randomized, double-blind, controlled trials that enrolled patients having an exacerbation of asthma were included. The main outcome measure was pulmonary function; hospital admission rate was also evaluated.

RESULTS

Ten studies including 1,483 adults with acute asthma were selected (mean age 32 +/- 13 years, 36% men). The overall effect size in SD units of pulmonary function showed a significant benefit from ipratropium (effect size 0.14, 95% confidence interval [CI]: 0.04 to 0.24, P = 0.008). Study-specific effect sizes ranged from 0.03 to 0.63. This pooled effect size was equivalent to a 10% (95% CI: 2% to 18%) increase in forced expiratory volume in 1 second (FEV1) or peak expiratory flow in the ipratropium group compared with the control group. Analysis of the four studies that included patients with extreme obstruction (FEV1 or peak flow <35% of predicted at presentation) showed substantial improvement with ipratropium therapy (effect size 0.38, 95% CI: 0.09 to 0.67). In the five trials (1,186 patients) that studied the effect of ipratropium administration on hospital admissions, pooled results revealed that ipratropium reduced admission rates significantly (odds ratio 0.62, 95% CI: 0.44 to 0.88, P = 0.007).

CONCLUSIONS

The addition of ipratropium to beta-agonist therapy offers a statistically significant, albeit modest, improvement in pulmonary function, as well as a reduction in the rate of hospital admissions.

Corticosteroids in the emergency department therapy of acute adult asthma: an evidence-based evaluation

OBJECTIVE

To review the literature to determine the benefits of corticosteroids (CCSs) (oral, IM, IV, or inhaled) in the treatment of adult patients with acute asthma presenting at an acute-care setting.

SEARCH STRATEGY

A MEDLINE search was conducted using the following terms: (1) Asthma OR Wheez, AND (2) Glucocorticoids OR Steroids, AND (3) Acute OR Emerg. Other sources were the CURRENT CONTENTS database, review articles, reference sections of located studies, and a manual search of the top 15 journals for respiratory and emergency medicine.

SELECTION CRITERIA

Patients were selected for the study by the following criteria: (1) English language; (2) adult patients with asthma whose acute exacerbations were the primary reason for assessment; (3) involvement in randomized, controlled trials conducted in an emergency care setting; (4) patients had participated in a study investigating a primary research question involving treatment with CCSs; and (5) outcomes based on results of pulmonary function tests and on hospital admission rates.

RESULTS

At the 3-h assessment, only high doses of inhaled CCSs significantly improved pulmonary function compared with placebo (effect size [ES], 0.56; 95% confidence interval [CI], 0.15 to 0.97). On the other hand, after receiving IV CCSs, patients required at least 6 to 24 h to show moderate but nonsignificant improvements of pulmonary function (6-h ES, 0.44 [95% CI, -0.01 to 0.89]; 12-h ES, 0.54 [95% CI, -0.08 to 1.17]; and 24-h ES, 0.53 [95% CI, -0.39 to 1.45]). The data from the six studies that we used to pool information on admission rate outcome showed a 32% reduction in favor of the use of IV CCSs (relative risk [RR], 0.68 [95% CI, 0.47 to 0.99]; number needed to treat, 12.5 [95% CI, 7.1 to 50]). However, the pooled effect of the three high-quality studies showed no difference between groups (RR, 1.21; 95% CI, 0.67 to 2.18). Oral CCSs provided a similarly beneficial effect on pulmonary function when compared with parenteral administration (ES, -0.14; 95% CI, -0.82 to 0.31. Finally, the results showed a nonsignificant favorable trend toward improved outcome with medium or high doses of CCSs.

CONCLUSIONS

This evidence-based evaluation suggests that the administration of parenteral CCSs to the patient on arrival at the emergency department (ED) neither improves airflow obstruction nor reduces the need for hospitalization. Parenteral CCSs probably require >6 to 24 h to begin to act. Comprehensible conclusions about admission rates in the ED setting are difficult to make. At the 3-h assessment, only high doses of inhaled CCSs (in one study) significantly improved pulmonary function compared with placebo. IV and oral CCSs appear to have equivalent effects, and there is a tendency toward improvement in pulmonary function with medium or high doses.

A high dose of albuterol does not overcome bronchoprotective subsensitivity in asthmatic subjects receiving regular salmeterol or formoterol

BACKGROUND

Regular treatment with inhaled, long-acting beta2 -agonists is associated with subsensitivity for bronchoprotective effects. It is not known whether a high dose of short-acting beta2 -agonist could overcome this subsensitivity.

OBJECTIVES

The objective of this study was to investigate the acute effects of a high dose of inhaled albuterol on methacholine-induced bronchoconstriction in patients receiving regular treatment with salmeterol or formoterol.

METHODS

Ten stable asthmatic subjects (mean age, 34 years; FEV1, 77% of predicted value), all taking inhaled corticosteroids (methacholine PD20 < 500 microg), were recruited into a randomized, single-blind, crossover study. After an initial 1-week run-in period, subjects underwent 3 separate treatment periods each of 9 days (separated by a washout of at least 5 days) comprising inhaled placebo twice daily, inhaled salmeterol dry powder 50 microg twice daily, or inhaled formoterol dry powder 12 microg twice daily. Methacholine challenge was performed 1 hour after the first dose and after 7 days of treatment. After 9 days of treatment, a third methacholine challenge was performed 1 hour after inhalation of a single 1600 microg dose of albuterol dry powder.

RESULTS

There was significant (P <.001) improvement in geometric mean PD20 after the first dose of active treatment as compared with placebo (78 microg) versus salmeterol (266 microg, a 3.4-fold difference [95% CI 1.9 to 6.1]) and versus formoterol (318 microg, a 4.1-fold difference [95% CI 2.3 to 7.3]). This bronchoprotection diminished with regular treatment, although it remained significant (P <.01) compared with placebo (68 microg) versus salmeterol (144 microg, a 2.1-fold difference [95% CI 1.2 to 3.8]) and versus formoterol (230 microg, 3.4-fold difference [95% CI 1.9 to 6.2]). After 9 days, the protection afforded by a single dose of albuterol after placebo pretreatment (889 microg) was significantly (P =.005) higher in comparison with albuterol protection after salmeterol pretreatment (338 microg, a 2.7-fold difference [95% CI 1.1 to 6.8]) and after formoterol pretreatment (247 microg, a 3.6-fold difference [95% 1.4 to 9.1]).

CONCLUSIONS

Thus in stable asthmatic subjects receiving regular salmeterol or formoterol, bronchoprotective subsensitivity was not overcome by administering a high dose of albuterol. Further studies are required to evaluate the clinical relevance of this pharmacologic phenomenon when albuterol is used in acute asthma.

Treatment of childhood asthma. Options and rationale for inhaled therapy

Epidemiological studies suggest the prevalence of asthma is increasing, though some remain sceptical as to the magnitude or indeed the presence of an increase. However, despite improved diagnosis and the availability of the potent drugs now available there remains considerable respiratory morbidity associated with asthma. It is clear from a number of studies that failure to deliver drugs to the lungs when using inhaler devices is a factor contributing to this high level of morbidity. Failure of drug delivery may result from the prescribing of inappropriate devices, failure to use devices appropriately or failure to comply with a treatment regimen. For most of the currently available forms of asthma therapy there are significant advantages to be gained from administering them in aerosol form. The benefits to be derived from administering these drugs as an aerosol include a rapid onset of action for drugs such as beta-agonists and a low incidence of systemic effects from drugs such as beta-agonists and corticosteroids. Over the past 25 years our understanding of the nature of asthma has changed. Though this has been reflected in the emphasis on inhaled corticosteroid therapy in recent guidelines, it has not been reflected in the range of inhaler devices available. Manufacturers continue to place drugs such as corticosteroids in the same devices as short acting beta-agonists even though the requirements for these different drug classes are very different. It is likely that this contributes to suboptimal therapeutic responses with inhaled corticosteroids. However, the variability associated with current delivery systems is relatively small compared with the variability introduced by poor compliance. There is no work currently available to indicate how the use of cheap disposable devises which do not incorporate any form of positive feedback influence compliance with inhaled steroids. Optimising aerosolised drug delivery in childhood involves consideration of the class of drugs, the particular drug within a class but more importantly, the age and abilities of the child. Devices must be selected to suit a particular child's needs and abilities. Devices utilising tidal breathing are generally used such as spacing chambers or, less commonly these days, nebulisers. A screaming or struggling child, or failure to use a closely fitting mask, reduces drug delivery to the lungs enormously. Failure to respond to inhaled therapy in early childhood may be attributable to failure of drug delivery. Drug delivery in early childhood using current devices remains more an art than a science.