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

Intravenous or nebulised magnesium sulphate versus standard therapy for severe acute asthma (3Mg trial): a double-blind, randomised controlled trial

BACKGROUND

Previous studies suggested intravenous or nebulised magnesium sulphate (MgSO(4)) might improve respiratory function in patients with acute asthma. We aimed to determine whether intravenous or nebulised MgSO(4) improve symptoms of breathlessness and reduce the need for hospital admission in adults with severe acute asthma.

METHODS

In our double-blind, placebo-controlled trial, we enrolled adults (aged ≥16 years) with severe acute asthma at emergency departments of 34 hospitals in the UK. We excluded patients with life-threatening features or contraindication to study drugs. We used a central randomisation system to allocate participants to intravenous MgSO(4) (2 g in 20 min) or nebulised MgSO(4) (three 500 mg doses in 1 h) alongside standard therapy including salbutamol, or placebo control plus standard therapy alone. We assessed two primary outcome measures in all eligible participants who started treatment, according to assigned treatment group: the proportion of patients admitted to hospital within 7 days and breathlessness measured on a 100 mm visual analogue scale (VAS) in the 2 h after initiation of treatment. We adjusted for multiple testing using Simes's method. The trial stopped before recruitment was completed because funding expired. This study is registered, number ISRCTN04417063.

FINDINGS

Between July 30, 2008, and June 30, 2012, we recruited 1109 (92%) of 1200 patients proposed by the power calculation. 261 (79%) of 332 patients allocated nebulised MgSO(4) were admitted to hospital before 7 days, as were 285 (72%) of 394 patients allocated intravenous MgSO(4) and 281 (78%) of 358 controls. Breathlessness was assessed in 296 (89%) patients allocated nebulised MgSO(4), 357 (91%) patients allocated intravenous MgSO(4), and 323 (90%) controls. Rates of hospital admission did not differ between patients treated with either form of MgSO(4) compared with controls or between those treated with nebulised MgSO(4) and intravenous MgSO(4). Change in VAS breathlessness did not differ between active treatments and control, but change in VAS was greater for patients in the intravenous MgSO(4) group than it was in the nebulised MgSO(4) group (5·1 mm, 0·8 to 9·4; p=0·019). Intravenous or nebulised MgSO(4) did not significantly decrease rates of hospital admission and breathlessness compared with placebo: intravenous MgSO(4) was associated with an odds ratio of 0·73 (95% CI 0·51 to 1·04; p=0·083) for hospital admission and a change in VAS breathlessness of 2·6 mm (-1·6 to 6·8; p=0·231) compared with placebo; nebulised MgSO(4) was associated with an odds ratio of 0·96 (0·65 to 1·40; p=0·819) for hospital admission and a change in VAS breathlessness of -2·6 mm (-7·0 to 1·8; p=0·253) compared with placebo.

INTERPRETATION

Our findings suggest nebulised MgSO(4) has no role in the management of severe acute asthma in adults and at best suggest only a limited role for intravenous MgSO(4) in this setting.

FUNDING

UK National Institute for Health Research Health Technology Assessment Programme.

Inhaled magnesium sulfate in the treatment of acute asthma

BACKGROUND

Asthma exacerbations can be frequent and range in severity from relatively mild to status asthmaticus. The use of magnesium sulfate (MgSO(4)) is one of numerous treatment options available during acute exacerbations. While the efficacy of intravenous MgSO(4) has been demonstrated, little is known of the role of inhaled MgSO(4).

OBJECTIVES

To determine the efficacy of inhaled MgSO(4) administered in acute asthma on pulmonary functions and admission rates.

SPECIFIC AIMS

To quantify the effects of inhaled MgSO(4) i) in addition to inhaled β(2)-agonist, ii) in comparison to inhaled β(2)-agonist alone or iii) in addition to combination treatment with inhaled β(2) -agonist and ipratropium bromide.

SEARCH METHODS

Randomised controlled trials were identified from the Cochrane Airways Group register of trials in September 2012. These trials were supplemented with trials found in the reference list of published studies, studies found using extensive electronic search techniques, as well as a review of the grey literature and conference proceedings.

SELECTION CRITERIA

Randomised (or pseudo-randomised) controlled trials including adults or children with acute asthma were eligible for inclusion in the review. Studies were included if patients were treated with nebulised MgSO(4) alone or in combination with β(2)-agonist and/or ipratropium bromide and were compared with β(2)-agonist alone or inactive control.

DATA COLLECTION AND ANALYSIS

Trial selection, data extraction and risk of bias were assessed independently by two review authors. Efforts were made to collect missing data from authors. Results are presented as standardised mean differences (SMD) for pulmonary function and risk ratios (RR) for hospital admission; both are displayed with their 95% confidence intervals (CI).

MAIN RESULTS

Sixteen trials (21 references) of unclear and high risk of bias were eligible and included 896 patients who were randomised (838 patients completed). Seven of the 16 included studies involved adults exclusively, three included adults and paediatric patients, four studies enrolled paediatric patients and in the remaining two studies the age of participants was not stated.The design, definitions, intervention and outcomes were different in all 16 studies; this heterogeneity made direct comparisons difficult (see additional tables 1-3).The overall risk of bias among the included studies was variable and this is reflected in the 'Summary of findings' table with most outcomes being judged as only moderate or less.Inhaled magnesium sulfate in addition to inhaled β(2)-agonistThere was no statistically significant improvement in pulmonary function when inhaled MgSO(4) and β(2)-agonist was compared with β(2)-agonist alone (SMD 0.23; 95% CI -0.27 to 0.74; three studies, n = 188); however, there was considerable between study heterogeneity. There was no clear advantage in terms of hospital admissions (RR 0.76 95% CI 0.49, 1.16; four studies, n = 249), and there were no serious adverse events reported.Inhaled magnesium sulfate versus inhaled β(2)-agonistThe results of pulmonary function in three studies that compared inhaled MgSO(4) versus β(2)-agonist were too heterogeneous to combine; however, two of the studies found poorer lung function on MgSO(4). There was no significant difference in terms of hospital admissions in a single small study when MgSO(4) was compared to β(2)-agonist (RR 0.53 95% CI 0.05, 5.31; one study, n = 33), and there were no serious adverse events reported.Inhaled magnesium sulfate in addition to inhaled β(2)-agonist and ipratropiumA further comparison has been included in the 2012 update of this review of MgSO(4) given in addition to inhaled ipratropium and β(2)-agonist therapy (as recommended by the GINA guidelines). However, there is not yet enough data for this outcome to come to any definite conclusions, but both small studies in adults with severe asthma exacerbation found improvements in pulmonary function with additional inhaled MgSO(4).

AUTHORS' CONCLUSIONS

There is currently no good evidence that inhaled MgSO(4) can be used as a substitute for inhaled β(2)-agonists. When used in addition to inhaled β(2)-agonists (with or without inhaled ipratropium), there is currently no overall clear evidence of improved pulmonary function or reduced hospital admissions. However, individual study results from three trials suggest possible improved pulmonary function in those with severe asthma exacerbations (FEV1 less than 50% predicted). Heterogeneity among trials included in this review precludes a more definitive conclusion. Further studies should focus on inhaled MgSO(4) in addition to the current guideline treatment for acute asthma (inhaled β(2) -agonist and ipratropium bromide). As the evidence suggests that the most effective role of nebulised MgSO(4) may be in those with severe acute features and this is where future research should be focused. A set of core outcomes needs to be agreed upon both in adult and paediatric studies to allow improved study comparison in future. 

The Saudi initiative for asthma - 2012 update: Guidelines for the diagnosis and management of asthma in adults and children

This an updated guidelines for the diagnosis and management of asthma, developed by the Saudi Initiative for Asthma (SINA) group, a subsidiary of the Saudi Thoracic Society. The main objective of SINA is to have updated guidelines, which are simple to understand and easy to use by non-asthma specialists, including primary care and general practice physicians. This new version includes updates of acute and chronic asthma management, with more emphasis on the use of Asthma Control Test in the management of asthma, and a new section on "difficult-to-treat asthma." Further, the section on asthma in children was re-written to cover different aspects in this age group. The SINA panel is a group of Saudi experts with well-respected academic backgrounds and experience in the field of asthma. The guidelines are formatted based on the available evidence, local literature, and the current situation in Saudi Arabia. There was an emphasis on patient-doctor partnership in the management that also includes a self-management plan. The approach adopted by the SINA group is mainly based on disease control as it is the ultimate goal of treatment.

Critical care in the ED: potentially fatal asthma and acute lung injury syndrome

Emergency department clinicians are frequently called upon to assess, diagnose, and stabilize patients who present with acute respiratory failure. This review describes a rapid initial approach to acute respiratory failure in adults, illustrated by two common examples: (1) an airway disease - acute potentially fatal asthma, and (2) a pulmonary parenchymal disease - acute lung injury/acute respiratory distress syndrome. As such patients are usually admitted to hospital, discussion will be focused on those initial management aspects most relevant to the emergency department clinician.

The critically ill asthmatic--from ICU to discharge

Status asthmaticus (SA) is defined as an acute, severe asthma exacerbation that does not respond readily to initial intensive therapy, while near-fatal asthma (NFA) refers loosely to a status asthmaticus attack that progresses to respiratory failure. The in-hospital mortality rate for all asthmatics is between 1% to 5%, but for critically ill asthmatics that require intubation the mortality rate is between 10% to 25% primarily from anoxia and cardiopulmonary arrest. Timely evaluation and treatment in the clinic, emergency room, or ultimately the intensive care unit (ICU) can prevent the morbidity and mortality associated with respiratory failure. Fatal asthma occurs from cardiopulmonary arrest, cerebral anoxia, or a complication of treatments, e.g., barotraumas, and ventilator-associated pneumonia. Mortality is highest in African-Americans, Puerto Rican-Americans, Cuban-Americans, women, and persons aged ≥ 65 years. Critical care physicians or intensivists must be skilled in managing the critically ill asthmatics with respiratory failure and knowledgeable about the few but potentially serious complications associated with mechanical ventilation. Bronchodilator and anti-inflammatory medications remain the standard therapies for managing SA and NFA patients in the ICU. NFA patients on mechanical ventilation require modes that allow for prolonged expiratory time and reverse the dynamic hyperinflation associated with the attack. Several adjuncts to mechanical ventilation, including heliox, general anesthesia, and extra-corporeal carbon dioxide removal, can be used as life-saving measures in extreme cases. Coordination of discharge and follow-up care can safely reduce the length of hospital stay and prevent future attacks of status asthmaticus.

Management of asthma in children with long QT syndrome

The Long QT syndrome (LQTS) is a rare disorder in which patients are prone to life threatening ventricular arrhythmia and is a leading cause of sudden death in childhood. Asthma is common and its management in those with LQTS presents a number of potential difficulties. The mainstay of therapy in LQTS is beta-blockade, which may worsen symptoms of asthma. Conversely, beta-agonist therapy is the mainstay of asthma management; which, in those with LQTS, may provoke ventricular arrhythmias. We review available data regarding the management of coexistent LQTS and asthma, and provide a summary of the necessary considerations in managing these patients.

Acute exacerbations of chronic obstructive pulmonary disease in the emergency department

Chronic obstructive pulmonary disease (COPD) is a significant cause of morbidity and mortality worldwide. Acute exacerbations of COPD (AECOPDs) are a common presentation to emergency departments and are an important cause of respiratory failure. This article discusses the disease process and diagnosis of COPD and AECOPD. A further in-depth discussion is undertaken of evidence-based treatments, palliation, and disposition of patients who present to emergency departments with AECOPD.

Leukotriene receptor antagonists in addition to usual care for acute asthma in adults and children

BACKGROUND

Acute asthma presentation in the emergency setting frequently leads to hospital admission. Currently available treatment options include corticosteroid therapy, beta(2)-agonists and oxygen. Antileukotriene agents are beneficial in chronic asthma as additional therapy to inhaled steroids. Their value when used orally or intravenously in the acute setting requires evaluation.

OBJECTIVES

To determine if the addition of a leukotriene receptor antagonist (LTRA) produces a beneficial effect in children and adults with acute asthma who are currently receiving inhaled bronchodilators and systemic corticosteroids.

SEARCH METHODS

We searched the Cochrane Airways Group's Specialised Register of trials with predefined terms. Searches are current to February 2012.

SELECTION CRITERIA

We included randomised trials comparing antileukotrienes and standard acute asthma care versus placebo and standard care in people with acute asthma of any age. We considered any dose and method of delivery of the leukotriene agent.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion in the review and extracted data. We then checked data and resolved disagreements by discussion. We contacted study authors where necessary to provide additional information and data.

MAIN RESULTS

Eight trials, generating 10 treatment-control comparisons, that recruited 1470 adults and 470 children met the entry criteria. These studies were of mixed quality, and there was heterogeneity in the severity of asthma exacerbation.For oral treatment, there was no significant difference in hospital admission between LTRAs and control in three trials on 194 children (risk ratio (RR) 0.86; 95% confidence interval (CI) 0.21 to 3.52). Using a broader composite outcome which measured requirement for additional care there was no significant difference between treatments (RR 0.87; 95% CI 0.60 to 1.28). Results demonstrated some indication of improvement in lung function with a significant difference in forced expiratory volume in one second (FEV(1)) favouring LTRAs in two trials on 641 adults (mean difference (MD) 0.08; 95% CI 0.01 to 0.14). There were insufficient data to assess this outcome in children. The most common adverse event described was headache; however, there was no significant difference between LTRAs and control (RR 0.81; 95% CI 0.22 to 2.99). Due to insufficient numbers, we were unable to conduct a subgroup analysis based on age.The combined results of two trials of intravenous treatment in 772 adults and one trial in 276 children demonstrated a reduction in the risk of hospital admission which was not quite statistically significant (RR 0.78; 95% CI 0.61 to 1.01). There was a statistically significant small difference in FEV(1) in the adult studies (MD 0.12; 95% CI 0.06 to 0.17), but not in the single trial in children (MD 0.01; 95% CI -0.06 to 0.08).

AUTHORS' CONCLUSIONS

Presently, the available evidence does not support routine use of oral LTRAs in acute asthma. Further studies are required to assess whether intravenous treatment can reduce the risk of hospital admission, and what the most appropriate dose regimen is. Additional research is also needed into safety and efficacy of additional doses for those on maintenance therapy, and larger paediatric trials are required to allow subgroup analysis. Prolonged studies would be required to establish other health economic outcomes in admitted patients.

Common pediatric respiratory emergencies

Pediatric respiratory illnesses are a huge burden to emergency departments worldwide. This article reviews the latest evidence in the epidemiology, assessment, management, and disposition of children presenting to the emergency department with asthma, croup, bronchiolitis, and pneumonia.

Magnesium sulfate for acute asthma in adults: a systematic literature review

Magnesium sulfate (MgSO(4)) has been considered as an adjunct therapy for severe and life-threatening asthma exacerbation. The literature search was performed using MEDLINE, EMBASE, Cochrane Library and Google Scholar to summarize the current state of knowledge regarding magnesium therapy in acute exacerbation of adult asthma. A total of 16 trials and 4 meta-analyses were identified. As results, intravenous MgSO(4) was beneficial in severe exacerbation, but evidence for nebulized magnesium was insufficient. However, larger trials are required to draw confirmative conclusions on the efficacy. Regarding the safety concern, the risk of major toxicity appears to be very low at usual doses described in the literature. Additionally, results from 4 surveys were examined on the gaps between knowledge and practice, and on the barrier to the use of MgSO(4) at emergency departments. This literature review summarized the up-to-date evidence on the issues regarding the use of MgSO(4) for acute asthma. We expect more studies to be conducted for evidence making in the Asian-Pacific regions.

Understanding implementation processes of clinical pathways and clinical practice guidelines in pediatric contexts: a study protocol

Background

Canada is among the most prosperous nations in the world, yet the health and wellness outcomes of Canadian children are surprisingly poor. There is some evidence to suggest that these poor health outcomes are partly due to clinical practice variation, which can stem from failure to apply the best available research evidence in clinical practice, otherwise known as knowledge translation (KT). Surprisingly, clinical practice variation, even for common acute paediatric conditions, is pervasive. Clinical practice variation results in unnecessary medical treatments, increased suffering, and increased healthcare costs. This study focuses on improving health outcomes for common paediatric acute health concerns by evaluating strategies that improve KT and reduce clinical practice variation.

Design/Methods

Using a multiple case study design, qualitative and quantitative data will be collected from four emergency departments in western Canada. Data sources will include: pre- and post-implementation focus group data from multidisciplinary healthcare professionals; individual interviews with the local champions, KT intervention providers, and unit/site leaders/managers; Alberta Context Tool (ACT) survey data; and aggregated patient outcome data. Qualitative and quantitative data will be systematically triangulated, and matrices will be built to do cross-case comparison. Explanations will be built about the success or lack of success of the clinical practice guidelines (CPG) and clinical pathways (CPs) uptake based upon the cross-case comparisons.

Significance

This study will generate new knowledge about the potential causal mechanisms and factors which shape implementation. Future studies will track the impact of the CPG/CPs implementation on children's health outcome, and healthcare costs.

Acute bronchial asthma

Acute asthma is the third commonest cause of pediatric emergency visits at PGIMER. Typically, it presents with acute onset respiratory distress and wheeze in a patient with past or family history of similar episodes. The severity of the acute episode of asthma is judged clinically and categorized as mild, moderate and severe. The initial therapy consists of oxygen, inhaled beta-2 agonists (salbutamol or terbutaline), inhaled budesonide (three doses over 1 h, at 20 min interval) in all and ipratropium bromide and systemic steroids (hydrocortisone or methylprednisolone) in acute severe asthma. Other causes of acute onset wheeze and breathing difficulty such as pneumonia, foreign body, cardiac failure etc. should be ruled out with help of chest radiography and appropriate laboratory investigations in first time wheezers and those not responding to 1 h of inhaled therapy. In case of inadequate response or worsening, intravenous infusion of magnesium sulphate, terbutaline or aminophylline may be used. Magnesium sulphate is the safest and most effective alternative among these. Severe cases may need ICU care and rarely, ventilatory support.

Acute lung failure

Lung failure is the most common organ failure seen in the intensive care unit. The pathogenesis of acute respiratory failure (ARF) can be classified as (1) neuromuscular in origin, (2) secondary to acute and chronic obstructive airway diseases, (3) alveolar processes such as cardiogenic and noncardiogenic pulmonary edema and pneumonia, and (4) vascular diseases such as acute or chronic pulmonary embolism. This article reviews the more common causes of ARF from each group, including the pathological mechanisms and the principles of critical care management, focusing on the supportive, specific, and adjunctive therapies for each condition.

Beneficial Effects of Magnesium Supplementation

Magnesium is an essential mineral necessary for optimal cellular health and well-being. Many adults in the United States fail to get recommended amounts of magnesium from their diets. Even so, symptoms of magnesium deficiency are rarely seen; however, maintaining normal body stores could be preventative against common diseases.

Pharmacologic approaches to life-threatening asthma

Following a peak in asthma mortality in the late 1980s and early 1990s, we have been fortunate to see a substantial decrease in asthma deaths in recent years. Although most asthma deaths occur outside the hospital, near-fatal events are commonplace, with anywhere from 2-20% of patients with acute asthma admitted to intensive care, and 2-4% intubated for respiratory failure. Standard therapies for acute severe and near-fatal asthma include administration of systemic corticosteroids, and frequent or continuous inhaled beta agonists. Controversy remains regarding the optimal therapy of those who fail to respond to these initial treatments, those who remain at risk of acute respiratory failure, and patients requiring mechanical ventilation. There remain significant gaps in our knowledge regarding relative benefits of intravenous versus oral corticosteroids, intermittent versus continuous beta agonists, and the role of various adjunctive treatments including intravenous magnesium, systemic beta agonists, aminophylline, and helium-oxygen mixtures. Using models and radiolabeled aerosols, there is a greater understanding regarding effective administration of inhaled beta-agonists in ventilated patients. There is limited available evidence for treatment of near-fatal asthma, a fact reflected by the significant variability in asthma critical care practice. Much of the data guiding treatment in this setting has been generalized from studies of acute asthma in the ED and from general populations of hospitalized patients with acute asthma. This review will focus on pharmacologic approaches to life-threatening asthma by reviewing current guideline recommendations, reviewing the scientific basis of the guidelines, and highlighting gaps in our knowledge in treatment of refractory acute or near-fatal asthma.

An integrative review of systematic reviews related to the management of breathlessness in respiratory illnesses

BACKGROUND

Breathlessness is a debilitating and distressing symptom in a wide variety of diseases and still a difficult symptom to manage. An integrative review of systematic reviews of non-pharmacological and pharmacological interventions for breathlessness in non-malignant disease was undertaken to identify the current state of clinical understanding of the management of breathlessness and highlight promising interventions that merit further investigation.

METHODS

Systematic reviews were identified via electronic databases between July 2007 and September 2009. Reviews were included within the study if they reported research on adult participants using either a measure of breathlessness or some other measure of respiratory symptoms.

RESULTS

In total 219 systematic reviews were identified and 153 included within the final review, of these 59 addressed non-pharmacological interventions and 94 addressed pharmacological interventions. The reviews covered in excess of 2000 trials. The majority of systematic reviews were conducted on interventions for asthma and COPD, and mainly focussed upon a small number of pharmacological interventions such as corticosteroids and bronchodilators, including beta-agonists. In contrast, other conditions involving breathlessness have received little or no attention and studies continue to focus upon pharmacological approaches. Moreover, although there are a number of non-pharmacological studies that have shown some promise, particularly for COPD, their conclusions are limited by a lack of good quality evidence from RCTs, small sample sizes and limited replication.

CONCLUSIONS

More research should focus in the future on the management of breathlessness in respiratory diseases other than asthma and COPD. In addition, pharmacological treatments do not completely manage breathlessness and have an added burden of side effects. It is therefore important to focus more research on promising non-pharmacological interventions.

[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.

Inhaled magnesium fluoride reverse bronchospasma

Asthma is a global health problem. Asthma attacks are becoming more severe and more resistant to usual treatment by beta(2) agonists nebulisation. The search for a new product that could reduce the morbidity of asthmatic disease seems necessary. The objective of this study was to compare the effectiveness of inhaled magnesium fluoride (MgF(2)) with that of magnesium sulphate (MgSO(4)) 15% alone and sodium fluoride (NaF) 0.5 M alone in rats pre-contracted by methacholine (MeCh). Fifty six adult male Wistar rats of medium weight 259 +/- 15 g were divided randomly into five groups. They inhaled respectively: MeCh, MgF(2) + NaCl 0.9%, MgF(2) + acetic acid, MgSO(4) 15% single and NaF (0.5 M) single. Airway resistances were measured after each dose of MeCh by pneumomultitest equipment. Results indicated that (1) MgF(2) + NaCl 0.9%, MgF(2) + acetic acid and MgSO(4) reversed significantly the methacholine-induced bronchial constriction in rats and had a bronchodilating effect at the moment of its administration (2) MgF(2) + acetic acid led to a greater decrease (P<0.05) of bronchial resistances when compared to that obtained from MgF(2) + NaCl 0.9%, NaF exclusively and MgSO(4) alone (3) inhaled NaF alone led to a significant bronchorelaxing effect (P<0.05) that starts at the sixth dose of MeCh (17 mg/L). As a matter of fact, MgF(2) dissolved in acetic acid and delivered in aerosol form reduces significantly bronchial spasm. In conclusion, MgF(2) can be used as a bronchodilator for diseases with bronchospasma such as asthma and chronic obstructive pulmonary disease (COPD).

Managing outpatient asthma exacerbations

Asthma is a chronic inflammatory disease that renders individuals vulnerable to acute exacerbations. A wide variety of allergic and nonallergic triggers can incite an asthma exacerbation. The goals of managing an asthma exacerbation are prompt recognition, rapid reversal of airflow obstruction, avoidance of relapses, and prevention of future episodes. A written asthma home management plan is essential to minimize the severity of exacerbations. Short-acting beta-agonists, oxygen, and corticosteroids remain fundamental to early intervention in acute asthma exacerbations. Anticholinergics and magnesium sulfate can help nonresponders. Combination inhalers of the long-acting beta-agonist formoterol and inhaled steroid budesonide have been effective in flexible dosing in treating early acute exacerbations and as a daily controller medication outside the United States. Initiation or intensification of long-term controller therapy, treatment of comorbid conditions, trigger avoidance, and prompt follow-up can help prevent relapses. Listening to patient preferences and concerns enhances adherence, and regular follow-up care can help prevent future episodes.

Comparative effectiveness of medical interventions in adults versus children

OBJECTIVE

To estimate the comparative effectiveness of medical interventions in adults versus children.

STUDY DESIGN

We identified from the Cochrane Database of Systematic Reviews (Issue 1, 2007) meta-analyses with data on at least 1 adult and 1 pediatric randomized trial with binary primary efficacy outcome. For each meta-analysis, we calculated the summary odds ratio of the adult trials and the pediatric trials, respectively; the relative odds ratio (ROR) of the adult versus pediatric odds ratios per meta-analysis; and the summary ROR across all meta-analyses. ROR <1 means that the experimental intervention is more unfavorable in children than adults.

RESULTS

Across 128 eligible meta-analyses (1051 adult and 343 pediatric trials), the summary ROR did not show a statistically significant difference between adults and children (0.96; 95% confidence intervals, 0.86 to 1.08). However, in all meta-analyses except for 1, the individual ROR's 95% confidence intervals could not exclude a relative difference in efficacy over 20%. In two-thirds, the relative difference in observed point estimates exceeded 50%. Nine statistically significant discrepancies were identified; 4 of them were also clinically important.

CONCLUSIONS

Treatment effects are on average similar in adults and children, but available evidence leaves large uncertainty about their relative efficacy. Clinically important discrepancies may occur.

The relationship between characteristics of context and research utilization in a pediatric setting

Background

Research utilization investigators have called for more focused examination of the influence of context on research utilization behaviors. Yet, up until recently, lack of instrumentation to identify and quantify aspects of organizational context that are integral to research use has significantly hampered these efforts. The Alberta Context Tool (ACT) was developed to assess the relationships between organizational factors and research utilization by a variety of healthcare professional groups. The purpose of this paper is to present findings from a pilot study using the ACT to elicit pediatric and neonatal healthcare professionals' perceptions of the organizational context in which they work and their use of research to inform practice. Specifically, we report on the relationship between dimensions of context, founded on the Promoting Action on Research Implementation in Health Services (PARIHS) framework, and self-reported research use behavior.

Methods

A cross-sectional survey approach was employed using a version of the ACT, modified specifically for pediatric settings. The survey was administered to nurses working in three pediatric units in Alberta, Canada. Scores for three dimensions of context (culture, leadership and evaluation) were used to categorize respondent data into one of four context groups (high, moderately high, moderately low and low). We then examined the relationships between nurses' self-reported research use and their perceived context.

Results

A 69% response rate was achieved. Statistically significant differences in nurses' perceptions of culture, leadership and evaluation, and self-reported conceptual research use were found across the three units. Differences in instrumental research use across the three groups of nurses by unit were not significant. Higher self-reported instrumental and conceptual research use by all nurses in the sample was associated with more positive perceptions of their context.

Conclusions

Overall, the results of this study lend support to the view that more positive contexts are associated with higher reports of research use in practice. These findings have implications for organizational endeavors to promote evidence-informed practice and maximize the quality of care. Importantly, these findings can be used to guide the development of interventions to target modifiable characteristics of organizational context that are influential in shaping research use behavior.

Usefulness of inhaled magnesium sulfate in the coadjuvant management of severe asthma crisis in an emergency department

RATIONALE

Treatment of severe asthma may be difficult despite the use of several medications including parenteral corticosteroids. Intravenous magnesium sulfate (MgSO(4)) is one ancillary drug for severe crisis; its inhaled use is controversial.

OBJECTIVES

To evaluate the usefulness of inhaled MgSO(4) compared to placebo in improving lung function, oxygen saturation, and reducing hospital admission as an adjunct to standard treatment in severe asthma crisis.

PATIENTS AND METHODS

We conducted a placebo-controlled, double-blind clinical trial with asthmatic patients >18 years of age with asthmatic crisis and FEV(1)<60% of predicted (%p). All subjects received 125 mg of IV methylprednisolone followed by nebulization with the combination of albuterol (7.5mg) and ipratropium bromide (1.5mg) diluted in 3 ml of isotonic saline solution (as placebo) or 3 ml (333 mg) of MgSO(4). After 90 min, subjects with FEV(1)<60%p or SpO(2)<88% or persistent symptoms were admitted to the emergency department (ED).

RESULTS

We included 30 patients per group who were similar at baseline. The MgSO(4) group showed higher post-bronchodilator (post-BD) FEV(1)%p (69+/-13 vs. 61+/-12, p<0.014) and SpO(2) (92+/-4 vs. 88+/-5%, p<0.006) than the placebo group. Fewer treated patients were admitted to the ED (5 vs. 13) (p<0.047), with relative risk (RR) of 0.26 (95% CI 0.079-0.870).

CONCLUSIONS

Adding inhaled MgSO(4) treatment to standard therapy in severe asthma crisis improves FEV(1)%p and SpO(2) post-BD and reduces the rate of ED admissions.

The Saudi Initiative for Asthma

The Saudi Initiative for Asthma (SINA) provides up-to-date guidelines for healthcare workers managing patients with asthma. SINA was developed by a panel of Saudi experts with respectable academic backgrounds and long-standing experience in the field. SINA is founded on the latest available evidence, local literature, and knowledge of the current setting in Saudi Arabia. Emphasis is placed on understanding the epidemiology, pathophysiology, medications, and clinical presentation. SINA elaborates on the development of patient-doctor partnership, self-management, and control of precipitating factors. Approaches to asthma treatment in SINA are based on disease control by the utilization of Asthma Control Test for the initiation and adjustment of asthma treatment. This guideline is established for the treatment of asthma in both children and adults, with special attention to children 5 years and younger. It is expected that the implementation of these guidelines for treating asthma will lead to better asthma control and decrease patient utilization of the health care system.

Magnesium for treatment of asthma in children

QUESTION

Magnesium is considered adjuvant therapy for moderate to severe asthma exacerbations in adults, but can it be used to treat children?

ANSWER

Magnesium seems to be beneficial in the treatment of moderate to severe asthma in children. It is a safe drug to administer, but there have been minor side effects reported, such as epigastric or facial warmth, flushing, pain and numbness at the infusion site, dry mouth, malaise, and hypotension. Owing to its bronchodilating and anti-inflammatory effects, magnesium is an encouraging adjuvant therapy for pediatric patients who do not respond to conventional treatment in acute severe exacerbations. Future studies should focus on establishing the optimal dosage for maximal benefits and the best route of administration. Magnesium should also be considered as a prophylactic treatment.

Acute severe asthma: new approaches to assessment and treatment

The precise definition of a severe asthmatic exacerbation is an issue that presents difficulties. The term 'status asthmaticus' relates severity to outcome and has been used to define a severe asthmatic exacerbation that does not respond to and/or perilously delays the repetitive or continuous administration of short-acting inhaled beta(2)-adrenergic receptor agonists (SABA) in the emergency setting. However, a number of limitations exist concerning the quantification of unresponsiveness. Therefore, the term 'acute severe asthma' is widely used, relating severity mostly to a combination of the presenting signs and symptoms and the severity of the cardiorespiratory abnormalities observed, although it is well known that presentation does not foretell outcome. In an acute severe asthma episode, close observation plus aggressive administration of bronchodilators (SABAs plus ipratropium bromide via a nebulizer driven by oxygen) and oral or intravenous corticosteroids are necessary to arrest the progression to severe hypercapnic respiratory failure leading to a decrease in consciousness that requires intensive care unit (ICU) admission and, eventually, ventilatory support. Adjunctive therapies (intravenous magnesium sulfate and/or others) should be considered in order to avoid intubation. Management after admission to the hospital ward because of an incomplete response is similar. The decision to intubate is essentially based on clinical judgement. Although cardiac or respiratory arrest represents an absolute indication for intubation, the usual picture is that of a conscious patient struggling to breathe. Factors associated with the increased likelihood of intubation include exhaustion and fatigue despite maximal therapy, deteriorating mental status, refractory hypoxaemia, increasing hypercapnia, haemodynamic instability and impending coma or apnoea. To intubate, sedation is indicated in order to improve comfort, safety and patient-ventilator synchrony, while at the same time decrease oxygen consumption and carbon dioxide production. Benzodiazepines can be safely used for sedation of the asthmatic patient, but time to awakening after discontinuation is prolonged and difficult to predict. The most common alternative is propofol, which is attractive in patients with sudden-onset (near-fatal) asthma who may be eligible for extubation within a few hours, because it can be titrated rapidly to a deep sedation level and has rapid reversal after discontinuation; in addition, it possesses bronchodilatory properties. The addition of an opioid (fentanyl or remifentanil) administered by continuous infusion to benzodiazepines or propofol is often desirable in order to provide amnesia, sedation, analgesia and respiratory drive suppression. Acute severe asthma is characterized by severe pulmonary hyperinflation due to marked limitation of the expiratory flow. Therefore, the main objective of the initial ventilator management is 2-fold: to ensure adequate gas exchange and to prevent further hyperinflation and ventilator-associated lung injury. This may require hypoventilation of the patient and higher arterial carbon dioxide (PaCO(2)) levels and a more acidic pH. This does not apply to asthmatic patients intubated for cardiac or respiratory arrest. In this setting the post-anoxic brain oedema might demand more careful management of PaCO(2) levels to prevent further elevation of intracranial pressure and subsequent complications. Monitoring lung mechanics is of paramount importance for the safe ventilation of patients with status asthmaticus. The first line of specific pharmacological therapy in ventilated asthmatic patients remains bronchodilation with a SABA, typically salbutamol (albuterol). Administration techniques include nebulizers or metered-dose inhalers with spacers. Systemic corticosteroids are critical components of therapy and should be administered to all ventilated patients, although the dose of systemic corticosteroids in mechanically ventilated asthmatic patients remains controversial. Anticholinergics, inhaled corticosteroids, leukotriene receptor antagonists and methylxanthines offer little benefit, and clinical data favouring their use are lacking. In conclusion, expertise, perseverance, judicious decisions and practice of evidence-based medicine are of paramount importance for successful outcomes for patients with acute severe asthma.

Commercial versus home-made spacers in delivering bronchodilator therapy for acute therapy in children

BACKGROUND

Strong evidence supports the use of metered-dose inhalers combined with a spacer for delivering rapid-acting inhaled beta-2 agonists in the treatment of acute exacerbations of asthma in children. The high cost and lack of availability of commercially produced spacers however, have limited their use in developing countries.

OBJECTIVES

The aim of this review was to compare the response to inhaled beta-2 agonists delivered through metered-dose inhaler using home-made spacers, to the use of commercially produced spacers, in children with acute exacerbations of wheezing or asthma.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) The Cochrane Library Issue 3, 2007,(up to August 2007) MEDLINE , EMBASE, CINHAL, LILACS and reference lists of included studies. We contacted authors and known experts in the field, and approached pharmaceutical companies that manufacture inhalation spacers to identify additional published or unpublished data. No language restrictions were applied.

SELECTION CRITERIA

Trials comparing treatment with rapid acting beta 2-agonists delivered though MDI attached to home-made spacers, with the same bronchodilator therapy delivered with MDI and commercially produced spacers, in children under 18 years with acute exacerbations of wheezing or asthma.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted the data and assessed trial quality. Missing data were obtained from the authors or estimated from information available in published reports.

MAIN RESULTS

Six trials with 658 participants met the inclusion criteria . At the time of this report, five trials were published in full text, and one study was available in abstract form only. No significant differences were demonstrated between the two delivery methods in terms of need for hospital admission (RR 1.00, 95% CI 0.63 to 1.59), change in oxygen saturation (SMD -0.03, 95% CI -0.39 to 0.33), PEFR (SMD 0.04, 95% CI -0.72 to 0.80), clinical score (WMD 0.00, 95% CI -0.37 to 0.37), in terms of need for additional treatment (RR 1.18, 95% CI 0.84 to 1.65), or regarding change in heart rate per minute (SMD 0.09, 95% CI -0.24 to 0.42).

AUTHORS' CONCLUSIONS

Overall, this review supports did not identify a difference between these two methods for delivering bronchodilator therapy to children with acute asthma or lower airways obstruction attacks. Care should be taken in the interpretation and applicability of our results because of the small number of RCTs along with few events available meeting the criteria for inclusion in the review, absence of the primary outcome of interest and other clinically important outcomes in the majority of included studies. The possible need for a face-mask in younger children using home-made spacers should also be considered in practice.

Intravenous and nebulised magnesium sulphate for acute asthma: systematic review and meta-analysis

OBJECTIVES

To estimate the effect of intravenous and nebulised magnesium sulphate upon hospital admissions and pulmonary function in adults and children with acute asthma.

METHODS

We undertook a systematic review and meta-analysis of randomised and quasi-randomised trials of intravenous or nebulised magnesium sulphate in acute asthma. Trials were identified by searches of the electronic literature, relevant journal websites and conference proceedings, and contact with authors and experts. Data were pooled using random effects meta-analysis of the relative risk (RR) of hospital admission and the standardised mean difference (SMD) in pulmonary function.

RESULTS

24 studies (15 intravenous, 9 nebulised) incorporating 1669 patients were included. Intravenous treatment was associated in adults with weak evidence of an effect upon respiratory function (SMD 0.25, 95% confidence interval (CI) -0.01 to 0.51; p = 0.05), but no significant effect upon hospital admission (RR 0.87, 95% CI 0.70 to 1.08; p = 0.22), and in children with a significant effect upon respiratory function (SMD 1.94, 95% CI 0.80 to 3.08; p<0.001) and hospital admission (RR 0.70, 95% CI 0.54 to 0.90; p = 0.005). Nebulised treatment was associated in adults with weak evidence of an effect upon respiratory function (SMD 0.17, 95% CI -0.02 to 0.36; p = 0.09), and hospital admission (RR 0.68, 95% CI 0.46 to 1.02; p = 0.06), and in children with no significant effect upon respiratory function (SMD -0.26, 95% CI -1.49 to 0.98; p = 0.69) or hospital admission (RR 2.0, 95% CI 0.19 to 20.93; p = 0.56).

CONCLUSION

Intravenous magnesium sulphate appears to be an effective treatment in children. Further trials are needed of intravenous and nebulised magnesium sulphate in adults and nebulised magnesium sulphate in children.

State of the evidence on acute asthma management in children: a critical appraisal of systematic reviews

OBJECTIVE

Our goal was to evaluate clinical, methodologic, and reporting aspects of systematic reviews on the management of acute asthma in children.

METHODS

We undertook a systematic review of systematic reviews on acute asthma management in children. We identified eligible reviews by searching the Cochrane Database of Systematic Reviews, the Database of Abstracts of Reviews of Effects, Medline, and Embase 1990 to March 2006. Data were extracted on clinical issues, methodologic characteristics, and results of the reviews. Methodologic quality was assessed with the Overview Quality Assessment Questionnaire and with additional questions on heterogeneity. Separate reporting on children in mixed adult-pediatric population reviews was assessed. Methodologic quality of systematic reviews published in peer-reviewed journals was compared with Cochrane reviews.

RESULTS

A total of 23 systematic reviews were included: 14 were published in the Cochrane Library, and 9 were published in peer-reviewed journals. Eight reviews included children only, and 15 were mixed-population reviews. The majority of reviews defined the study population as having "acute asthma" without a more precise definition, and 16 different health outcomes were reported. The overall quality according to the Overview Quality Assessment Questionnaire was good, with Cochrane reviews showing minimal flaws and journal reviews showing minor flaws (median scores: 7 vs 5). Results on children were reported separately in 8 of 15 mixed-population reviews. Clinical heterogeneity was explored in only 2 of 23 reviews, and the methods used to identify and address heterogeneity were diverse.

CONCLUSIONS

The methodologic quality of both the Cochrane and journal reviews on the management of acute asthma in children seems good, with Cochrane reviews being more rigorous. However, their usefulness for clinical practice is hampered by a lack of clear definitions of included populations, clinically important health outcomes, and separate reporting on children in mixed reviews. A major threat to these reviews' validity is the insufficient identification and handling of heterogeneity.

Magnesium sulfate for persistent pulmonary hypertension of the newborn

BACKGROUND

Persistent pulmonary hypertension of the newborn (PPHN) occurs in approximately 1.9 per 1000 newborns and may be more frequent in developing countries. There is strong evidence for the use of inhaled nitric oxide (iNO) and extra corporeal membrane oxygenation (ECMO) in the treatment of PPHN. However, many developing countries do not have access or the technical expertise required for these expensive therapies. Magnesium sulfate is a potent vasodilator and hence has the potential to reduce the high pulmonary arterial pressures associated with PPHN. If magnesium sulfate were found to be effective in the treatment of PPHN, this could be a cost effective and potentially life-saving therapy.

OBJECTIVES

To evaluate the use of magnesium sulfate compared with placebo or standard ventilator management alone, sildenafil infusion, adenosine infusion, or inhaled nitric oxide on mortality or the use of backup iNO or ECMO in term and near-term newborns (> 34 weeks gestational age) with PPHN.

SEARCH STRATEGY

The standard search strategy of the Cochrane Neonatal Review Group (CNRG) was used. No language restrictions was applied. The Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 1, 2006) and MEDLINE (1966 to April 20, 2007) were searched for relevant randomized and quasi-randomized trials. In addition the reference lists of retrieved articles were reviewed and known experts were contacted to obtain unpublished data.

SELECTION CRITERIA

All randomised or quasi-random studies were eligible where one of the treatment groups received magnesium sulfate for PPHN.

DATA COLLECTION AND ANALYSIS

Standard methods of the Cochrane Collaboration and the CNRG were used, including independent assessment of trial quality and extraction of data by each author.

MAIN RESULTS

No eligible trials were found

AUTHORS' CONCLUSIONS

On the basis of the current lack of evidence, the use of magnesium sulphate cannot be recommended in the treatment of PPHN. Randomised controlled trials are recommended.

Comparison of nebulised magnesium sulphate and salbutamol combined with salbutamol alone in the treatment of acute bronchial asthma: a randomised study

OBJECTIVE

To test the hypothesis that combined administration of multiple doses of nebulised salbutamol and magnesium sulphate provides additional benefit compared with salbutamol alone in adult patients with acute asthma.

DESIGN

Randomised, double blind, prospective study.

METHODS

A total of 100 patients presenting to an emergency department with an acute attack of bronchial asthma were randomised to two groups: nebulisation with a combination of salbutamol and magnesium sulphate (group A) and nebulisation with salbutamol only (group B). Both groups received nebulisation thrice at intervals of 20 minutes. Salbutamol and magnesium sulphate were administered in doses of 0.5 mg and 500 mg, respectively, and the solutions were made isotonic to plasma osmolality. Pulse rate, blood pressure, and peak expiratory flow rate (PEFR) were measured at baseline and at 15, 60, 75, and 120 minutes. Serum magnesium levels and blood gases were measured at 0 and 120 minutes in both groups.

RESULTS

All patients had either acute severe or life threatening asthma. The baseline characteristics were comparable in the two groups. Both groups showed significant rise in PEFR at all time intervals, however, there was no significant difference between the groups in rise in PEFR at any time point. Serum magnesium levels remained within normal limits, and there was no difference in requirement of additional medication during the study or hospital admission rates in both groups. No significant side effects were noted.

CONCLUSION

This study suggests that there is no therapeutic benefit of adding magnesium sulphate to salbutamol nebulisation in the treatment of patients with acute severe or life threatening asthma.

Short and long term treatment of asthma with intravenous nutrients

Background

Asthma is an increasing problem in this country and others. Although medications for the treatment of asthma abound and are improving, there are inherent risks and side effects with all of them. Intravenous magnesium has been employed in the treatment of acute asthma, but its use has not become universal, nor has it been studied for the treatment of chronic asthma. It is known to be a safe drug with minimal side effects. In this study, the author investigates the use of magnesium and other nutrients in the treatment of both acute and chronic asthma.

Methods

In this non-blinded outcome study, following informed consent, forty-three (43) randomly selected volunteer patients with both acute and chronic asthma were treated with IV infusions described herein. All patients were observed with spirometry 10 minutes post-infusion; two sub-groups of patients were also observed after multiple infusions over a short period of time (less than one month) and a longer period of time (average 5.8 months). Pulmonary function was analyzed by spirometric testing with pre- and post-infusion spirometric measurements with the pre/post group. For longer term (Trend) patients, baseline spirometry measurements were compared to spirometry measurements after patients had received multiple infusions over a period of time. Eight (8) patients were measured for both pre/post and Trend data.

Results

The 38 pre-infusion/post-infusion patients with acute and chronic asthma demonstrated an overall average improvement (percentage improvement in percent predicted) of 45%. The 13 patients measured for improvement over time (Trend data, average duration 5.82 months), demonstrated an overall average improvement (percentage improvement in percent predicted) of 57%. Of the 13 patients in the multiple infusion group, 9 patients who received longer-term therapy (average duration of 12.58 months) for chronic asthma demonstrated an overall average improvement of 95% (percentage improvement in percent predicted).

Conclusion

The use of intravenous treatment with multiple nutrients, including magnesium, for acute and chronic asthma may be of considerable benefit. Pulmonary function improved progressively the longer patients received treatment.

Update on Cochrane data on paediatric respiratory diseases

INTRODUCTION

Systematic reviews seek to describe and summarise the best evidence for a given intervention by pooling data from relevant quality clinical trials. The Cochrane Collaboration has fostered the development and dissemination of systematic reviews throughout the world. We have identified and summarised The Cochrane systematic reviews of relevance to the paediatric pulmonologist.

METHODS

We performed an expert search of the Cochrane Database of Systematic Reviews using a combination of medical subject headings and free text terms relating to paediatric respiratory disease.

RESULTS

The search identified 120 systematic reviews with interventions specific to children with some relevance to pulmonary disease, and 327 reviews with interventions relating to pulmonary disease in adults and children. After pragmatic exclusions, 81 reviews were sorted by disease and 59 of these are discussed in detail.

CONCLUSIONS

There are now many systematic reviews that make a positive contribution to paediatric pulmonology. The majority of reviews (69%) found evidence that either confirmed or refuted an accepted practice. The remaining reviews concluded that the evidence for an accepted practice is poor and sometimes wholly absent. Clinicians must be aware that lack of evidence of effect is not the same as evidence of lack of effect. Caution must be exercised before applying the conclusions of systematic reviews based upon adult data to childhood disease.

Efficacy of a consensus protocol therapy in adults with acute, severe asthma

BACKGROUND

International guidelines recommend multiple doses of inhaled beta2-agonists and anticholinergics plus early administration of systemic corticosteroids for acute, severe asthma. This study examined the efficacy of this protocol in adults and analyzed those factors associated with unresponsiveness to the protocol therapy.

OBJECTIVE

Ninety-three consecutive patients 18 to 55 years old presenting for treatment of acute asthma with a peak expiratory flow rate (PEFR) < or = 50% of the predicted value were analyzed.

METHODS

All subjects received 400 microg of salbutamol every 20 minutes for three doses and 400 microg of oxitropium bromide with each of the three salbutamol doses by means of a metered-dose inhaler with a spacer device, plus intravenously 8 mg betamethasone. PEFR was measured at baseline and at 20, 40, 60, and 120 minutes.

RESULTS

Sixty-nine percent of subjects improved sufficiently to be discharged. In 31% of subjects, the protocol therapy failed. There were no significant differences in age, sex, smoking status, or beta-agonist use within 6 hours between the two groups. Logistic regression analysis demonstrated that a PEFR < 35% of the predicted value at presentation (odds ratio [OR]; 16.3, 95% confidence interval [CI] 4.5 to 59.9), viral respiratory tract infection symptoms > or = 2 days (OR, 4.8, 95% CI 1.3 to 17.1), and asthma hospitalization in the past year (OR, 4.6, 95% CI 1.1 to 19.9) were significantly associated with unresponsiveness to the protocol.

CONCLUSIONS

Unresponsiveness to protocol therapy occurs in nearly one-third of individuals presenting with acute, severe asthma. Our findings underscore the need to explore more effective strategies for improving lung function and reducing hospital admission rates.

Managing outpatient asthma exacerbations

Asthma is a chronic inflammatory disease that renders individuals prone to acute exacerbations. Several allergic and nonallergic triggers can incite an asthma exacerbation. The goals of managing an asthma exacerbation are prompt recognition, rapid reversal of airflow obstruction, prevention of relapses, and forestalling future episodes. A written asthma home-management plan is essential to minimize the severity of exacerbations. Short-acting b-agonists, oxygen, and corticosteroids are fundamental to early intervention in acute asthma exacerbation. Anticholinergics and magnesium sulfate can help nonresponders. Newer agents such as levalbuterol and long-acting b-agonists might be future additions to our armamentarium of drugs to treat acute exacerbations. Initiation or intensification of long-term controller therapy, treatment of co-morbid conditions, and avoidance of possible triggers along with prompt follow-up can help prevent relapses. Listening to patient preferences and concerns to enhance adherence and regular follow-up care can help prevent future episodes.

Management of children with severe asthma exacerbation in the emergency department

Although acute asthma is a very common cause of emergency department visits in children, there is as yet insufficient evidence for the establishment of a standardized treatment protocol. The aim of this review is to describe updated information on the management of asthma exacerbations in the pediatric emergency department. Oxygen is the first-line treatment of acute asthma exacerbations in the emergency department to control hypoxemia. It is accompanied by the administration of beta(2)-adrenoceptor agonists followed by corticosteroids. beta(2)-Adrenoceptor agonists have traditionally been administered by nebulization, although spacers have recently been introduced and proven, in many cases, to be as effective as nebulization. Oral prednisolone, with its reliability, simplicity, convenience and low cost, should remain the treatment of choice for the most severe asthma exacerbations, when the lung airways are extremely contracted and filled with secretions. Recently, several studies have shown that high-dose inhaled corticosteroids are at least as effective as oral corticosteroids in controlling moderate to severe asthma attacks in children and therefore should be considered an alternative treatment to oral corticosteroids in moderate to severe asthma attacks. Studies of other drugs have shown that ipratropium bromide may be given only in addition to beta(2)-adrenoceptor agonists; theophylline has no additional benefit, and magnesium sulfate has no clear advantage. Comprehensive asthma management should also include asthma education, measures to prevent asthma triggers, and training in the use of inhalers and spacers. Proper management will avoid most asthma attacks and reduce admission and readmission to emergency departments.

Respiratory and allergic diseases: from upper respiratory tract infections to asthma

Patients with asthma and allergic rhinitis may benefit from hydration and a diet low in sodium, omega-6 fatty acids, and transfatty acids, but high in omega-3 fatty acids (i.e., fish, almonds, walnuts, pumpkin, and flax seeds), onions, and fruits and vegetables (at least five servings a day). Physicians may need to be more cautious when prescribing antibiotics to children in their first year of life when they are born to families with a history of atopy. More research is needed to establish whether supplementation with probiotics (lactobacillus and bifidobacterium) during the first year of life or after antibiotic use decreases the risk of developing asthma and allergic rhinitis. Despite a theoretic basis for the use of vitamin C supplements in asthmatic patients, the evidence is still equivocal, and long-term studies are needed. The evidence is stronger for exercise-induced asthma, in which the use of vitamin C supplementation at a dosage of 1 to 2 g per day may be helpful. It is also possible that fish oil supplements, administered in a dosage of 1 to 1.2 g of EPA and DHA per day, also may be helpful to some patients with asthma. Long-term studies of fish oil and vitamin C are needed for more definite answers. For the patient interested in incorporating nutritional approaches, vitamin C and fish oils have a safe profile. However, aspirin-sensitive individuals should avoid fish oils, and red blood cell magnesium levels may help in making the decision whether to use additional magnesium supplements. Combination herbal formulas should be used in the treatment of asthma with medical supervision and in collaboration with an experienced herbalist or practitioner of TCM. Safe herbs, such as Boswellia and gingko, may be used singly as adjuncts to a comprehensive plan of care if the patient and practitioner have an interest in trying them while staying alert for drug-herb interactions. No data on the long-term use of these single herbs in asthma exist. For the motivated patient, mind-body interventions such as yoga, hypnosis, and biofeedback-assisted relaxation and breathing exercises are beneficial for stress reduction in general and may be helpful in further controlling asthma. Encouraging parents to learn how to massage their asthmatic children may appeal to some parents and provide benefits for parents and children alike. Acupuncture and chiropractic treatment cannot be recommended at this time, although some patients may derive benefit because of the placebo effect. For patients with allergic rhinitis, there are no good clinical research data on the use of quercetin and vitamin C. Similarly, freeze-dried stinging nettle leaves may be tried, but the applicable research evidence also is poor. Further studies are needed to assess the efficacy of these supplements and herbs. Homeopathic remedies based on extreme dilutions of the allergen may be beneficial in allergic rhinitis but require collaboration with an experienced homeopath. There are no research data on constitutional homeopathic approaches to asthma and allergic rhinitis. Patients with COPD are helped by exercise, pulmonary rehabilitation, and increased caloric protein and fat intake. Vitamin C and n-3 supplements are safe and reasonable; however, studies are needed to establish their efficacy in COPD. On the other hand, there are convincing data in favor of N-acetyl-cysteine supplementation for the patient with COPD at doses ranging between 400 and 1200 mg daily. Red blood cell magnesium levels may guide the use of magnesium replacement. The use of L-carnitine and coenzyme Q10 in patients with COPD needs further study. The addition of essential oils to the dietary regimen of patients with chronic bronchitis is worth exploring. Patients with upper respiratory tract infections can expect a shorter duration of symptoms by taking high doses of vitamin C (2 g) with zinc supplements, preferably the nasal zinc gel, at the onset of their symptoms. Adding an herb such as echinacea or Andrographis shortens the duration of the common cold. The one study on Elderberry's use for the flu was encouraging, and the data on the homeopathic remedy Oscillococcinum interesting, but more studies should be performed. Saline washes may be helpful to patients with allergic rhinitis and chronic sinusitis. Patients also may try the German combination (available in the United States) of elderberry, vervain, gentian, primrose, and sorrel that has been tested in randomized clinical trials. Bromelain is safe to try; the trials of bromelain supplementation were promising but were never repeated. The preceding suggestions need to be grounded in a program based on optimal medical management. Patients need to be well educated in the proper medical management of their disease and skilled at monitoring disease stability and progress. Asthmatic patients need to monitor their bronchodilator usage and peak flow meter measurements to step up their medical treatment in a timely manner, if needed. Patients welcome physician guidance when exploring the breadth of treatments available today. A true patient-physician partnership is always empowering to patients who are serious about regaining their function and health.

Randomized clinical trial of intravenous magnesium sulfate as an adjunctive medication for emergency department treatment of migraine headache

STUDY OBJECTIVE

We test the hypothesis that intravenous magnesium sulfate is an effective adjunctive medication for treatment of acute migraine.

METHODS

In this randomized, double-blind, placebo-controlled trial, adults presenting to 2 urban emergency departments with headache meeting International Headache Society criteria for acute migraine received either 20 mg of intravenous metoclopramide plus 2 g of intravenous magnesium sulfate or 20 mg of intravenous metoclopramide plus a placebo of intravenous saline solution at 15-minute intervals for a maximum of 3 doses or until pain relief occurred. At 0, 15, 30, and 45 minutes, patients recorded pain intensity using a standard visual analog scale (VAS). The primary study end point was the between-group difference in pain improvement when initial and final VAS scores were compared.

RESULTS

Of 44 patients enrolled (21 randomized to metoclopramide plus magnesium and 23 to metoclopramide plus placebo), 42 (95%) were women. Baseline features were comparable in both groups. Each group experienced a more than 50-mm improvement in VAS score during the study. However, this improvement was smaller in the magnesium group for the primary end point (16-mm difference favoring placebo [95% confidence interval (CI) -2 to 34 mm]), as was the proportion with normal functional status at their final rating (36% absolute difference also favoring placebo [95% CI 7% to 65%]). Using a 50% reduction in pain to dichotomize VAS scores, the number needed to harm with magnesium plus metoclopramide versus metoclopramide alone is 4 patients (95% CI 2 to 36).

CONCLUSION

Although this result was unexpected, our data suggest that the addition of magnesium to metoclopramide may attenuate the effectiveness of metoclopramide in relieving migraine. Countertherapeutic cerebral vasodilatation caused by magnesium is a plausible, although unproven, explanation for this finding. Because of the preponderance of women in our trial, these data may not be generalizable to men.