Corticosteroids in acute severe asthma: effectiveness of low doses

Different oral corticosteroid regimens for acute asthma

BACKGROUND

Asthma is a common long-term breathing condition that affects approximately 300 million people worldwide. People with asthma may experience short-term worsening of their asthma symptoms; these episodes are often known as 'exacerbations', 'flare-ups', 'attacks' or 'acute asthma'. Oral steroids, which have a potent anti-inflammatory effect, are recommended for all but the most mild asthma exacerbations; they should be initiated promptly. The most often prescribed oral steroids are prednisolone and dexamethasone, but current guidelines on dosing vary between countries, and often among different guideline producers within the same country. Despite their proven efficacy, use of steroids needs to be balanced against their potential to cause important adverse events. Evidence is somewhat limited regarding optimal dosing of oral steroids for asthma exacerbations to maximise recovery while minimising potential side effects, which is the topic of this review.

OBJECTIVES

To assess the efficacy and safety of any dose or duration of oral steroids versus any other dose or duration of oral steroids for adults and children with an asthma exacerbation.

SEARCH METHODS

We identified trials from the Cochrane Airways Group Specialised Register (CAGR), ClinicalTrials.gov (www.ClinicalTrials.gov), the World Health Organization (WHO) trials portal (www.who.int/ictrp/en/) and reference lists of all primary studies and review articles. This search was up to date as of April 2016.

SELECTION CRITERIA

We included parallel randomised controlled trials (RCTs), irrespective of blinding or duration, that evaluated one dose or duration of oral steroid versus any other dose or duration, for management of asthma exacerbations. We included studies involving both adults and children with asthma of any severity, in which investigators analysed adults and children separately. We allowed any other co-intervention in the management of an asthma exacerbation, provided it was not part of the randomised treatment. We included studies reported as full text, those published as abstract only and unpublished data.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the search results for included trials, extracted numerical data and assessed risk of bias; all data were cross-checked for accuracy. We resolved disagreements by discussion with the third review author or with an external advisor.We analysed dichotomous data as odds ratios (ORs) or risk differences (RDs) using study participants as the unit of analysis; we analysed continuous data as mean differences (MDs). We used a random-effects model, and we carried out a fixed-effect analysis if we detected statistical heterogeneity. We rated all outcomes using the GRADE (Grades of Recommendation, Assessment, Development and Evaluation) system and presented results in 'Summary of findings' tables.

MAIN RESULTS

We included 18 studies that randomised a total of 2438 participants - both adults and children - and performed comparisons of interest. Included studies assessed higher versus lower doses of prednisolone (n = 4); longer versus shorter courses of prednisolone (n = 3) or dexamethasone (n = 1); tapered versus non-tapered courses of prednisolone (n = 4); and prednisolone versus dexamethasone (n = 6). Follow-up duration ranged from seven days to six months. The smallest study randomised just 15 participants, and the largest 638 (median 93). The varied interventions and outcomes reported limited the number of meaningful meta-analyses that we could perform.For two of our primary outcomes - hospital admission and serious adverse events - events were too infrequent to permit conclusions about the superiority of one treatment over the other, or their equivalence. Researchers in the included studies reported asthma symptoms in different ways and rarely used validated scales, again limiting our conclusions. Secondary outcome meta-analysis was similarly hampered by heterogeneity among interventions and outcome measures used. Overall, we found no convincing evidence of differences in outcomes between a higher dose or longer course and a lower dose or shorter course of prednisolone or dexamethasone, or between prednisolone and dexamethasone.Included studies were generally of reasonable methodological quality. Review authors assessed most outcomes in the review as having low or very low quality, meaning we are not confident in the effect estimates. The predominant reason for downgrading was imprecision, but indirectness and risk of bias also reduced our confidence in some estimates.

AUTHORS' CONCLUSIONS

Evidence is not strong enough to reveal whether shorter or lower-dose regimens are generally less effective than longer or higher-dose regimens, or indeed that the latter are associated with more adverse events. Any changes recommended for current practice should be supported by data from larger, well-designed trials. Varied study design and outcome measures limited the number of meta-analyses that we could perform. Greater emphasis on palatability and on whether some regimens might be easier to adhere to than others could better inform clinical decisions for individual patients.

[Adult asthma exacerbations in questions]

In this article a French working party critically review the international literature to revise the definition, pathophysiology, treatment and cost of exacerbations of adult asthma. The various guidelines do not always provide a consistent definition of exacerbations of asthma. An exacerbation can be defined as deterioration of clinical and/or functional parameters lasting more than 24 hours, without return to baseline, requiring a change of treatment. No single clinical or functional criterion can be used as an early marker of an exacerbation. Innate and acquired immune mechanisms, modified by contact with infectious, irritant or allergenic agents, participate in the pathogenesis of exacerbations, which are accompanied by bronchial inflammation. In 2010, mortality is related to progression of exacerbations, often occurring before the patient seeks medical attention. The objective of treatment is to control asthma and prevent exacerbations. However, many factors can trigger exacerbations and often cannot be controlled. The efficacy of inhaled corticosteroids has been demonstrated on reduction of the number of exacerbations and the number of asthma-related deaths. This treatment is cost-effective, especially in terms of reduction of exacerbations.

Comparing the efficacy and safety of two regimens of sequential systemic corticosteroids in the treatment of acute exacerbation of bronchial asthma

BACKGROUND

Corticosteroids are commonly used in the management of acute asthma. However, studies comparing various steroids in the management of acute asthma are lacking.

OBJECTIVE

To compare the efficacy and safety of two treatment regimens - intravenous (IV) methylprednisolone (MP) followed by oral MP and IV hydrocortisone (HC) followed by oral prednisolone in acute bronchial asthma patients.

MATERIALS AND METHODS

This was a randomized, prospective study performed in the emergency department (ED) of a tertiary care hospital in North India. A total of 94 patients with acute asthma were randomly allocated to either of the two treatment groups: Group A (n = 49) or Group B (n = 45). Patients in Group A were administered HC 200 mg IV 6-hourly until discharge from the ED, followed by oral prednisolone 0.75 mg/kg daily for 2 weeks. Patients in Group B were administered MP 125 mg IV bolus, followed by 40 mg MP IV 6-hourly until discharge, and then oral MP 0.6 mg/kg daily for 2 weeks. All clinical variables, peak expiratory flow (PEF) and forced expiratory volume in one second (FEV(1)) were assessed at baseline, at 1, 3 and 6 h and at every 6 h thereafter until discharge from the ED. The patients were followed-up after 2 weeks of discharge. The response to treatment was assessed by clinical and spirometric evaluation. Independent t-tests and chi-square tests were used to compare the two treatment regimens.

RESULTS

The baseline characteristics were comparable in the two groups. There was a significant improvement in PEF and FEV(1) within the groups at 2 weeks of treatment when compared to the baseline. At 2 weeks of follow-up, Group B showed significant improvement over Group A in PEF (P < 0.0001), FEV(1) (P < 0.0001) and asthma score (P = 0.034). There was a significant increase in the blood sugar value at 2 weeks in both the groups. However, the increase was greater in Group A as compared to Group B (P < 0.0001).

CONCLUSION

This study suggests that in acute asthma patients, IV MP followed by oral MP is a more efficacious and safer treatment regimen than IV HC followed by oral prednisolone.

An umbrella review: corticosteroid therapy for adults with acute asthma

The objective of this "umbrella" review is to synthesize the evidence and provide clinicians a single report that summarizes the state of knowledge regarding the use of corticosteroids in adults with acute asthma. Systematic reviews in the Cochrane Library and additional clinical trials published in English from 1966 to 2007 in MEDLINE, EMBASE, CINAHL, and Cochrane CENTRAL, and references from bibliographies of pertinent articles were reviewed. Results indicate that the evidence base is frequently limited to small, single-center studies. Findings suggest that therapy with systemic corticosteroids accelerates the resolution of acute asthma and reduces the risk of relapse. There is no evidence that corticosteroid doses greater than standard doses (prednisone 50-100 mg equivalent) are beneficial. Oral and intravenous corticosteroids, as well as intramuscular and oral corticosteroid regimens, seem to be similarly effective. A nontapered 5- to 10-day course of corticosteroid therapy seems to be sufficient for most discharged patients. Combinations of oral and inhaled corticosteroids on emergency department/hospital discharge might minimize the risk of relapse.

Asthma exacerbations. 5: assessment and management of severe asthma in adults in hospital

It is difficult to understand why there is such a huge discrepancy between the management of severe asthma recommended by evidence-based guidelines and that observed in clinical practice. The recommendations are relatively straightforward and have been widely promoted both in guidelines and reviews. Specialist physicians need to be more proactive in their implementation of such guidelines through the use of locally derived protocols and assessment sheets, reinforced by audit. The common occurrence of severe asthma and its considerable burden to the community would support such an approach.

Doses of systemic corticosteroids in hospitalised children with acute asthma: A systematic review

AIM

To present the doses of systemic corticosteroids reported by clinical trials in hospitalised children with acute asthma and to assess the possible relationship between doses of corticosteroids and clinical responses.

METHODS

An electronic search of MEDLINE databases (January 1949-February 2005) and Cochrane Controlled Clinical Trials Register (February 2005) was undertaken using a combination of indexing terms related to systemic corticosteroids and acute asthma. Studies were selected if they met the following criteria: (i) randomized controlled trial; (ii) children aged 1-18 years and admitted to hospital for acute asthma; and (iii) treatment group consisting of systemic corticosteroids.

RESULTS

Nine trials were included for this review. There was considerable variation between the reported doses of systemic corticosteroids. Only two trials assessed clinical responses to different doses of systemic corticosteroids. Both trials failed to show any therapeutic advantage of higher doses over lower doses. The results of the two trials were not suitable for pooling.

CONCLUSIONS

Current data are not sufficient for establishing dose-response relationship of systemic corticosteroids in hospitalised children with acute asthma. Larger randomized trials are needed.

Pharmacokinetics and pharmacodynamics of systemically administered glucocorticoids

Glucocorticoids have pleiotropic effects that are used to treat diverse diseases such as asthma, rheumatoid arthritis, systemic lupus erythematosus and acute kidney transplant rejection. The most commonly used systemic glucocorticoids are hydrocortisone, prednisolone, methylprednisolone and dexamethasone. These glucocorticoids have good oral bioavailability and are eliminated mainly by hepatic metabolism and renal excretion of the metabolites. Plasma concentrations follow a biexponential pattern. Two-compartment models are used after intravenous administration, but one-compartment models are sufficient after oral administration.The effects of glucocorticoids are mediated by genomic and possibly nongenomic mechanisms. Genomic mechanisms include activation of the cytosolic glucocorticoid receptor that leads to activation or repression of protein synthesis, including cytokines, chemokines, inflammatory enzymes and adhesion molecules. Thus, inflammation and immune response mechanisms may be modified. Nongenomic mechanisms might play an additional role in glucocorticoid pulse therapy. Clinical efficacy depends on glucocorticoid pharmacokinetics and pharmacodynamics. Pharmacokinetic parameters such as the elimination half-life, and pharmacodynamic parameters such as the concentration producing the half-maximal effect, determine the duration and intensity of glucocorticoid effects. The special contribution of either of these can be distinguished with pharmacokinetic/pharmacodynamic analysis. We performed simulations with a pharmacokinetic/pharmacodynamic model using T helper cell counts and endogenous cortisol as biomarkers for the effects of methylprednisolone. These simulations suggest that the clinical efficacy of low-dose glucocorticoid regimens might be increased with twice-daily glucocorticoid administration.

Oral versus intravenous corticosteroids in adults hospitalised with acute asthma

BACKGROUND

Systemic corticosteroids are routinely used in the management of acute asthma, however the optimum route of administration for patients requiring hospitalisation is unclear. Intravenous (IV) corticosteroids are used in practice, but they may not offer any advantage over oral corticosteroids.

AIM

To compare the efficacy of oral and IV administration of corticosteroids in the treatment of adults hospitalised with acute asthma.

METHOD

Adults admitted to hospital for treatment of acute asthma were randomised to receive oral prednisolone 100 mg once daily or hydrocortisone 100 mg IV 6 hourly for 72 h following admission. All patients concurrently received inhaled corticosteroids and bronchodilators. Improvements in peak expiratory flow rate (PEF) from baseline were compared for 72 h.

RESULTS

Forty-seven patients were randomized, 30 females, 17 males. Twenty-four received oral prednisolone and 23 received IV hydrocortisone. At baseline the oral and IV groups were similar (mean, SD) in age (38.3, 12.8 vs 37.3, 12.9, P=0.80) and initial percent predicted (PP) PEF (61, 16.7 vs 69, 13.0, P=0.11). After 72 h both groups had similar improvements in PEF (27%, 26 vs 27%, 19, P=0.96).

CONCLUSION

Corticosteroids administered orally and IV had similar efficacy in the treatment of adults hospitalised with acute asthma.

Severe exacerbations of asthma

All asthmatics regardless of their perceived severity, are at risk of exacerbation, particularly if they are suboptimally treated in the outpatient arena. Fortunately most patients recover after administration of bronchodilators and anti-inflammatory medications, but preventable deaths continue to occur and refractory cases result in hospitalization and need for mechanical ventilation. We begin this article by reviewing the pathophysiology of acute exacerbations to build a foundation for the assessment of clinical status and to provide the rationale for a carefully contemplated and evidence-based therapeutic approach. We end this article with an in-depth examination of the particular problems that are encountered during mechanical ventilation and offer a strategy that helps minimize complications. In the final analysis, however, the greatest gains in the field of acute asthma will come not from its treatment but from its prevention by enhanced educational and environmental efforts and by the delivery of optimal medications at home.

Randomised pragmatic comparison of UK and US treatment of acute asthma presenting to hospital

BACKGROUND

Systemic corticosteroids and inhaled beta(2) agonists are accepted first line treatments for acute severe asthma, but there is no consensus on their optimum dosage and frequency of administration. American regimens include higher initial dosages of beta(2) agonists and corticosteroids than UK regimens.

METHODS

In a prospective, pragmatic, randomised, parallel group study, 170 patients of mean (SD) age 37 (12) years with acute asthma (peak expiratory flow (PEF) 212 (80) l/min) presenting to hospital received treatment with either high dose prednisolone and continuous nebulised salbutamol as recommended in the US or lower dose prednisolone and bolus nebulised salbutamol as recommended in the UK by the BTS.

RESULTS

Outcome measures were: deltaPEF at 1 hour (BTS 89 l/min, US 106 l/min, p=0.2, CI -8 to 41) and at 2 hours (BTS 49 l/min, US 101 l/min, p<0.0001, CI 28 to 77); time to discharge if admitted (BTS 4 days, US 4 days); rates of achieving discharge PEF (>60%) at 2 hours (BTS 64%, US 78%, p=0.04); time to regain control of asthma as measured by PEF >/=80% best with </=20% variability (BTS 3 days, US 4 days, p=0.6); PEF at 24 hours in patients admitted (BTS 293 l/min, US 288 l/min, p=0.8); and control of asthma in the subsequent month (no significant differences).

CONCLUSIONS

Treatment with higher doses of continuous nebulised salbutamol leads to a greater immediate improvement in PEF but the degree of recovery at 24 hours and speed of recovery thereafter is achieved as effectively with lower corticosteroid doses as recommended in the British guidelines.

The management of acute severe asthma

Asthma is a common cause of morbidity and mortality in the United States, with over two million Emergency Department (ED) visits each year. Airway inflammation is recognized as a major component in the pathophysiology of asthma. The classic presentation of asthma is that of wheezing, cough, and dyspnea, however, the severity of airflow limitation correlates poorly with clinical signs. Forced exhaled volume in 1 s (FEV(1)) and the peak expiratory flow rate (PEFR) are direct reflections of the severity of airflow obstruction and are the standard measures used in the ED to assess the severity of airflow obstruction and the response to therapy. Beta2-adrenergic bronchodilators, ipratropium bromide, and corticosteroids form the cornerstone of therapy. Inhaled corticosteroids, leukotriene modifying drugs, and noninvasive positive pressure ventilation should be considered in patients with severe disease and in those who have responded poorly to standard therapy. Mechanical ventilation is usually well tolerated and may be lifesaving in patients with refractory asthma. Precautions are required to prevent dynamic hyperinflation during assisted ventilation.

The Management of Acute Severe Asthma

Acute severe asthma exacerbations resulting in emergency department visits and hospitalization usually constitute a failure of long-term control therapy. However, even patients with relatively mild asthma can have severe life-threatening episodes. In both children and adults, viral respiratory infections are the major triggering event, although outbreaks of severe asthma have been associated with high concentrations of aeroallergens. Patients should be provided with written action plans on what to do for acute deterioration, and more severe patients may keep prednisone at home to begin after consultation with their physician. The primary therapy of acute asthma exacerbations remains frequent administration of aerosol β2-agonists and systemic corticosteroids for those patients not fully responding to the β2-agonists. Mild exacerbations may be treated with an increased dosage of inhaled corticosteroids. Patients at risk for acute exacerbations may benefit from peak flow measurement, particularly those who have difficulty perceiving airway obstruction. It is recommended that patients remain on full dose of prednisone until they achieve 70-80 percent of predicted normal or personal best peak flow. In the emergency department, the use of β2-agonists by metered-dose inhaler and holding chamber is as effective as nebulizer if given in a sufficient dose 6-10 puffs equivalent to 5 mg via nebulizer. In those patients not responding completely, the addition of ipratropium bromide has shown to produce additive bronchodilation and reduce hospitalizations. Other therapies such as magnesium sulfate, intravenous β2-agonists, heliox and ketamine have been used, but data demonstrating efficacy are insufficient to warrant recommending their general use.

Corticosteroids for acute severe asthma in hospitalised patients

BACKGROUND

Corticosteroids are currently used routinely in the management of acute severe asthma. The optimal dose and route of administration continues to be debated. Some investigators have reported a greater benefit of higher doses of corticosteroids in the management of severe asthma, while others have not.

OBJECTIVES

To determine whether higher doses of systemic corticosteroids (oral, intravenous or intramuscular) are more effective than lower doses in the management of patients with acute severe asthma requiring hospital admission.

SEARCH STRATEGY

Randomised controlled trials were identified from the Cochrane Airways Group Asthma Register. In addition, primary authors and content experts were contacted to identify eligible studies. Bibliographies from included studies, known reviews and texts were also searched.

SELECTION CRITERIA

Studies were selected for inclusion in the review if they met the following broad inclusion criteria: described as randomised controlled trials, included patients with acute severe asthma, compared different doses of corticosteroids (any route) in 2 or more treatment arms, and had a minimum period of follow up of 24 hours. Two reviewers independently assessed the studies for inclusion and disagreement was resolved by third party adjudication.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two reviewers if the authors were unable to verify the validity of information. Missing data were obtained from authors or calculated from other data presented in the paper. The data were analysed as weighted mean differences (WMD) for primary pulmonary function outcomes using a fixed effects model. For the purposes of the review, three broad categories of corticosteroid dose (equivalent dose of methylprednisolone in 24 hours) were defined in advance: low dose (< or = 80 mg), medium dose (> 80 mg and < or = 360 mg) and high dose (> 360 mg). There were thus 3 main comparison groups: low versus medium dose, medium versus high dose and low versus high dose.

MAIN RESULTS

Nine trials were included; a total of 344 adult patients have been studied (96 with low dose, 85 with medium dose and 163 with high dose corticosteroids). Only 6 trials provided sufficient data for the meta-analysis. There were no clinically or statistically significant differences detected in % predicted FEV1 among comparison groups after 24, 48 or 72 hours. At 48 hours, the weighted mean difference was -3.3% predicted (95% confidence interval -12.4 to + 5.8) for the low vs medium dose comparison, -1. 9% predicted (95% CI -8.1 to + 4.3) for the medium vs high dose comparison and + 0.5% predicted (95% CI - 7.8 to + 8.8) for the low vs high dose comparison. There appeared to be no significant differences in side effects or rates of respiratory failure among the varying doses of corticosteroids.

REVIEWER'S CONCLUSIONS

No differences were identified among the different doses of corticosteroids in acute asthma requiring hospital admission. Low dose corticosteroids (< or = 80 mg/day of methylprednisolone or < or = 400 mg/day of hydrocortisone) appear to be adequate in the initial management of these adult patients. Higher doses do not appear to offer a therapeutic advantage.

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.

Myopathy following mechanical ventilation for acute severe asthma: the role of muscle relaxants and corticosteroids

BACKGROUND

Acute myopathy following mechanical ventilation for near-fatal asthma (NFA) has been described recently, and some researchers have suggested that this complication is related to the use of neuromuscular blocking agents (NMBAs) and corticosteroids (CSs).

OBJECTIVES

To determine the incidence of acute myopathy in a group of patients and to examine the most important predictors of its development.

DESIGN AND METHODS

A retrospective cohort study over a 10-year period (1985 to 1995) of all asthma patients who received mechanical ventilation at two centers in Vancouver (designated center 1 and center 2).

RESULTS

In center 1, there were 58 patients who had 64 episodes of NFA, and in center 2, there were 28 patients who had 30 episodes. NMBAs were used in 30 of 86 admissions for acute severe asthma (35%). The mean (+/- SD) duration of muscle paralysis was 3.1+/-2.3 days. A total of 9 patients (10.4%) developed significant myopathy. The incidence of myopathy was 9 of 30 (30%) among patients who received NMBAs. In a multiple logistic regression model, the development of myopathy was only significantly associated with the duration of muscle relaxation. The odds ratio for the development of myopathy increased by 2.1 (95% confidence interval, 1.4 to 3.2) with each additional day of muscle relaxation. The dose and the type of the CS were not significantly associated with the myopathy in the multiple logistic regression analysis.

CONCLUSION

Our study showed that there is a high incidence of acute myopathy when NMBAs are used for NFA. The incidence of myopathy increases with each additional day of muscle relaxation.

Status asthmaticus

Despite improved understanding of the pathophysiology and treatment of asthma, significant morbidity and mortality exist for both the pediatric and adult patient. The critical care practitioner must understand the chronic as well as the acute nature of the condition in order to provide effective intervention. This article reviews the epidemiology and pathophysiology of asthma, clinical assessment, management principles, therapeutic modalities, and future approaches to the management of asthma.

Results of a program to improve the process of inpatient care of adult asthmatics

OBJECTIVE

To assess the effectiveness of a program to improve care of adult patients hospitalized for asthma.

DESIGN

Retrospective analysis of patient and house staff education, patterns of medication use, spacer use, peak flowmeter use, and length of stay before and after team intervention.

SETTING

A 960-bed teaching hospital in New York City.

PATIENTS

All patients admitted to the hospital with a primary diagnosis of acute asthma exacerbation for 2 separate similar calendar periods, 1 year apart, before and after program intervention. We excluded patients who were hospitalized for less than 24 h or greater than 10 days. The preintervention group comprised 61 patients and the postintervention group 65 patients, well matched in their demographic characteristics and severity of disease.

INTERVENTIONS

Using a team approach, we analyzed the process of inpatient treatment of asthma exacerbation, identified root causes for quality deficiency, and implemented specific improvements in the process. These included dedicated nurses who focused on the education of care providers and patients, a personalized attending-intern educational approach, and improvement in the supply and delivery of spacers, peak flowmeters, and medications to the patients.

RESULTS

There was a significant increase in use of spacers, peak flowmeters, and inhaled corticosteroids. Systemic corticosteroid and methylxanthine use declined. Length of stay was reduced without increasing early hospital readmission rates.

CONCLUSIONS

This program improved the treatment process of adults hospitalized for asthma.

Guidelines for the emergency management of asthma in adults. CAEP/CTS Asthma Advisory Committee. Canadian Association of Emergency Physicians and the Canadian Thoracic Society

OBJECTIVE

To develop a set of comprehensive, standardized evidence-based guidelines for the assessment and treatment of acute asthma in adults in the emergency setting.

OPTIONS

The use of medications was evaluated by class, dose, route, onset of action and optimal mode of delivery. The use of objective measurements and clinical features to assess response to therapy were evaluated in relation to the decision to admit or discharge the patient or arrange for follow-up care.

OUTCOMES

Control of symptoms and disease reflected in hospital admission rates, frequency of treatment failures following discharge, resolution of symptoms and improvement of spirometric test results.

EVIDENCE

Previous guidelines, articles retrieved through a search of MEDLINE, emergency medical abstracts and information from members of the expert panel were reviewed by members of the Canadian Association of Emergency Physicians (CAEP) and the Canadian Thoracic Society. Where evidence was not available, consensus was reached by the expert panel. The resulting guidelines were reviewed by members of the parent organizations.

VALUES

The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used.

BENEFITS, HARMS AND COSTS

As many as 80% of the approximate 400 deaths from asthma each year in Canada are felt to be preventable. The use of guidelines, aggressive emergency management and consistent use of available options at discharge are expected to decrease the rates of unnecessary hospital admissions and return visits to emergency departments because of treatment failures. Substantial decreases in costs are expected from the use of less expensive drugs, or drug delivery systems, fewer hospital admissions and earlier return to full activity after discharge.

RECOMMENDATIONS

Beta2-agonists are the first-line therapy for the management of acute asthma in the emergency department (grade A recommendation). Bronchodilators should be administered by the inhaled route and titrated using objective and clinical measures of airflow limitation (grade A). Metered-dose inhalers are preferred to wet nebulizers, and a chamber (spacer device) is recommended for severe asthma (grade A). Anticholinergic therapy should be added to beta 2 agonist therapy in severe and life-threatening cases and may be considered in cases of mild to moderate asthma (grade A). Aminophylline is not recommended for use in the first 4 hours of therapy (grade A). Ketamine and succinylcholine are recommended for rapid sequence intubation in life-threatening cases (grade B). Adrenaline (administered subcutaneously or intravenously), salbutamol (administered intravenously) and anesthetics (inhaled) are recommended as alternatives to conventional therapy in unresponsive life-threatening cases (grade B). Severity of airflow limitation should be determined according to the forced expiratory volume at 1 second or the peak expiratory flow rate, or both, before and after treatment and at discharge (grade A). Consideration for discharge should be based on both spirometric test results and assessment of clinical risk factors for relapse (grade A). All patients should be considered candidates for systemic corticosteroid therapy at discharge (grade A). Those requiring corticosteroid therapy should be given 30 to 60 mg of prednisone orally (or equivalent) per day for 7 to 14 days; no tapering is required (grade A). Inhaled corticosteroids are an integral component of therapy and should be prescribed for all patients receiving oral corticosteroid therapy at discharge (grade A). Patients should be given a discharge treatment plan and clear instructions for follow-up care (grade C).

VALIDATION

The guidelines share the same principles of those from the British Thoracic Society and the National Institutes of Health. Two specific validation initiatives have been undertaken: (a) several Canadian centres have been involved in the collection of comprehensive administrative data to assess compliance and outcome measures and (b) a survey of Canadian emergency physicians conducted to gather baseline informaton of treatment patterns, was conducted before development of the guidelines and will be repeated to re-evaluate emergency management of asthma.

Emergent management of acute asthma

In almost no other field is the gap between diagnostic and therapeutic knowledge and its general application so great as it is in asthma. As previously mentioned, most asthma deaths are preventable. Identification of high-risk patients, intensive education about asthma (purpose of each medication; necessity of compliance, particularly with inhaled corticosteroids; proper use of inhalers and spacer devices; home use of PEFR meter), self-treatment of mild or moderate attacks with oral corticosteroids, and written crisis plan for severe attacks explicitly telling the patient what to do and whom to call are necessary. In addition, all potential exacerating factors should be eliminated (external triggers, medication, gastroesophageal reflux, allergic rhinitis, and sinusitis). High doses of inhaled corticosteroids should be provided to all those patients, and referral to a specialist is highly recommended for such high-risk patients.

Management of severe exacerbations of asthma

Asthma is a common disease that afflicts as many as 5% of Americans. Severe exacerbations of asthma can be life-threatening if not treated aggressively. Despite publication of therapeutic guidelines developed by experts in this field, the clinical management of severe exacerbations of asthma varies widely among institutions and practitioners. This article briefly reviews the pathophysiology of asthma and outlines a systematic, mechanistic approach to treating patients with severe asthma that integrates many clinical advancements made during the past 5 to 10 years.

A randomized comparison of 100-mg vs 500-mg dose of methylprednisolone in the treatment of acute asthma

There have been conflicting reports comparing the effects of various doses of corticosteroids in the treatment of acute asthma. The purpose of this study was to compare 100 mg with 500 mg of methylprednisolone in the emergency department treatment of acute asthma. We studied 150 patients presenting to the emergency department with acute asthma. After baseline pulmonary function testing, patients were treated with oxygen and hourly administration of aerosolized albuterol. Patients were randomized to receive either 100 or 500 mg of methylprednisolone intravenously. Spirometry was repeated at 3 h, and again at 5 h for those patients whose dyspnea had not resolved after 3 h. There was no difference in the FEV1 between the 500-mg and 100-mg dose groups either before treatment (38.0% vs 32.6% of predicted normal) or after treatment (55.3% vs 51.9% of predicted normal). There was no difference in the percentage improvement in FEV1 with treatment between the 500-mg and 100-mg dose groups (65.0% vs 71.2%). Twenty-five percent of the patients in the 500-mg dose group were admitted to the hospital compared with 28% of patients in the 100-mg dose group (not significant). We conclude that the administration of a 500-mg dose of methylprednisolone offers no advantages over a 100-mg dose in the emergency department treatment of acute asthma.

Early administration of hydrocortisone in the emergency room treatment of acute asthma: a controlled clinical trial

STUDY OBJECTIVE

To determine whether early administration of a single dose of intravenous hydrocortisone (500 mg) modified the need for hospitalization and duration of treatment, and improve pulmonary function assessed by subjective and objective criteria of acute asthma patients.

DESIGN

Randomized, double-blind, placebo-controlled trial.

SETTING

The emergency room (ER) of a large, urban hospital with primary and referral care responsibilities.

PATIENTS

Ninety-eight patients from 18 to 50 years of age with acute bronchial asthma, with a PEFR and FEV1 in the first second below 50% of predicted value (FEV1 mean % of predicted = 27.8 +/- 10.0) and without history of chronic cough or other medical disease.

INTERVENTIONS

The corticosteroid group received 500 mg of intravenous hydrocortisone whereas the control group received intravenous normal saline immediately after arrival to the ER. Additional treatment included salbutamol delivered with metered-dose inhaler into a spacer device (Volumatic), in four puffs actuated in rapid succession (100 micrograms per actuation), at 10-min intervals. The final mean dose was 5.7 mg for the steroid group and 5.6 mg for the control one (P = 0.86). Hospitalization was mandatory if total treatment time was greater than 6 h.

MEASUREMENTS AND RESULTS

Age, sex, PEFR, FEV1, FVC, symptom index, and corticosteroids use were similar in both groups. FEV1 expressed as mean % of predicted was 54.6 +/- 17.3% in the control group and 54.6 +/- 17.4% in the steroid group (P = 0.75). Duration of ER treatment was 2.22 +/- 1.75 h in the corticosteroid group and 2.24 +/- 1.70 h in the control group (P = 0.81). The hospital admission rate was 10.2% for the corticosteroid group and 8.16% for the control group. There were no differences between the groups when patients admitted or discharged were examined separately.

CONCLUSIONS

Early administration of corticosteroids does not modify outcome of ER treatment of asthma, and does not improve pulmonary function in the first 6 h of treatment. In accord with this, administration of corticosteroids to these patients could be delayed by several hours without modifying clinical outcome. When an aggressive beta-agonist bronchodilator regimen is used, it obviates the need for steroids in this early stage of treatment.