The role of ipratropium bromide in the emergency management of acute asthma exacerbation: a metaanalysis of randomized clinical trials

Management of the acute exacerbation of asthma

All patients with asthma are at risk of having asthma exacerbations characterized by worsening symptoms, airflow obstruction, and an increased requirement for rescue bronchodilators. The goals of managing an asthma exacerbation are prompt recognition and rapid reversal of airflow obstruction to avert relapses and future episodes. Short-acting beta-agonists, oxygen, and corticosteroids form the basis of management of acute asthma exacerbation, but a role is emerging for anticholinergics and newer agents such as levalbuterol and formoterol. Initiation or intensification of long-term controller therapy, treatment of comorbid conditions, avoidance of likely triggers, and timely follow-up care prevent setbacks. Acceptance of current treatment guidelines by physicians and adherence to the recommended clinical regimens by patients are essential for effective management of asthma. The physician should strive to establish a constructive relationship with the patient by addressing the patient's concerns, reaching agreement on the goals of therapy, and developing a written action plan for patient self-management.

Inhaled therapy for acute adult asthma

PURPOSE OF REVIEW

To evaluate recent developments on emergency department inhalotherapy in non-intubated acute adult asthma patients.

RECENT FINDINGS

There is evidence that high-flow oxygen can be associated with hypercarbia, and that full humidification of the inspired gases should be recommended. On the contrary, there is a lack of evidence to support the role of heliox in the initial treatment of acute asthma. Specific short-acting inhaled beta(2)-agonists are the drugs of choice. A more rapid and profound bronchodilatation with fewer side effects and less time of treatment can be achieved when sufficient doses are given using pressurized meter dose inhalers and large-volume valved-spacers, particularly in patients with the most severe obstruction. Findings argue against the routine use of continuous nebulization. High and repetitive doses of ipratropium bromide in combination with beta(2)-agonists are indicated as first line treatment of severe acute asthma. There is insufficient evidence that inhaled corticosteroids alone are as effective as systemic corticosteroids. Finally, the combination of nebulized magnesium and albuterol provides no benefit in addition to that provided by therapy with albuterol in patients with mild-to-moderate asthma exacerbations.

SUMMARY

According to the latest evidence, the goals of treatment may be summarized as follows: maintenance of adequate arterial oxygen saturation with supplemental oxygen, relief of airflow obstruction by administration of inhaled beta-agonists and anticholinergics, and reduction of airway inflammation and prevention of future relapses by using early administration of systemic corticosteroids.

Triple inhaled drug protocol for the treatment of acute severe asthma

STUDY OBJECTIVE

This study tests the hypothesis that the administration of multiple doses of inhaled albuterol (A), ipratropium bromide (IB), and flunisolide (F) provides an additional benefit to adults with acute severe asthma compared with the administration of A plus IB (A/IB) or A plus F (A/F).

DESIGN

Randomized, double-blind, prospective trial.

PATIENTS AND INTERVENTIONS

One hundred seventy-two patients who presented to an emergency department were assigned to receive A, IB, and F (ie, triple drug treatment [TDG]; 56 patients), A/IB (60 patients), or A/F (56 patients). All drugs were administered through a metered-dose inhaler and spacer at 10-min intervals for 3 h.

RESULTS

Patients who received TDG had an overall 64% greater improvement (95% confidence interval [CI], 24 to 103%; p = 0.002) in FEV(1) (mean [+/- SD], 2.1 +/- 0.6 L) than those who received A/F (mean, 1.7 +/- 0.6 L), and a 41% greater improvement (95% CI, 1 to 80%; p = 0.04) than those who received A/IB (mean, 1.8 +/- 0.6 L). Differences between groups increased with time (p = 0.001). At 3 h, there was a trend toward a reduction in hospital admission rates (A/IB group, 25%; A/F group, 20%; and TDG group, 11%). The patients who were the most likely to benefit (ie, those with a greater improvement in pulmonary function and a significant reduction in the hospitalization rate) from TDG were those with more severe obstruction (ie, FEV(1), < 30% of predicted). The benefit of TDG was equally evident independent of the patient's previous use of corticosteroids.

CONCLUSIONS

The data suggest that there was a therapeutic benefit from the addition of IB and F to A administered in high doses, particularly in those patients in whom the FEV(1) was < 30% of the predicted value.

Asthma evaluation and management

Asthma is a chronic inflammatory illness with acute exacerbations, which often is encountered in the ED setting. Knowledge of the presentation and treatment of asthma is crucial for any physician treating patients with this disease. Beta-agonist, anticholinergic, and corticosteroid therapy continue to be the mainstay of emergency therapy despite advances in newer medications. Proper attention to long-term treatment of asthma and aggressive treatment of acute exacerbations should help reduce morbidity and mortality.

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.

A randomized controlled trial of intravenous montelukast in acute asthma

Many patients with acute asthma do not respond adequately to currently accepted therapy, including oxygen, beta-agonists, and corticosteroids. Leukotriene receptor antagonists such as montelukast have demonstrated efficacy in chronic asthma, but their efficacy in acute asthma is unknown. In this randomized, double-blind, parallel-group pilot study, adults with moderate to severe acute asthma received standard therapy plus either intravenous montelukast (7 or 14 mg) or matching placebo. A total of 201 patients were randomized, and 194 had complete data available for analysis. There was no difference in FEV1 response between the 7- and 14-mg montelukast groups. Montelukast improved FEV1 over the first 20 minutes after intravenous administration (mean percentage change from prerandomization baseline, 14.8% versus 3.6% for the pooled montelukast and placebo treatment groups, respectively; p = 0.007). This benefit was observed at 10 minutes and over 2 hours after intravenous therapy. Patients treated with montelukast tended to receive less beta-agonists and have fewer treatment failures than patients receiving placebo. The tolerability profile for montelukast was similar to that observed for placebo, and no unexpected adverse experiences were observed. We conclude that intravenous montelukast in addition to standard therapy causes rapid benefit and is well tolerated in adults with acute asthma.

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

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

The 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 evaluation and management of acute, severe asthma

This article provides a systematic approach to the patient with acute, severe asthma. After a brief, focused evaluation prompt treatment with inhaled beta 2-agonists and systemic corticosteroids remains the cornerstone of treatment. Ipratropium bromide is now recognized as a useful addition for both adult and pediatric populations, whereas consideration of intravenous MgSO4 and theophylline is warranted for refractory patients. Ongoing evaluation of antileukotriene agents offers a possibility of these agents as alternative bronchodilators. Further research with a number of potential acute asthma agents will further expand treatment options for rapid symptomatic airway improvement and prevention of progressing airway obstruction, hospitalization, and potential respiratory failure.

The role of anticholinergics in acute asthma treatment: an evidence-based evaluation

The role for anticholinergic medications in acute asthma is not well-defined. Thus, the use of therapy with anticholinergics and beta(2)-agonists, either simultaneously or in sequence, has produced positive as well as negative results in trials. Therefore, the current recommendations for the use of these drugs in the emergency department (ED) and hospital management of asthma exacerbations are not precise. This review answers the following question: what level of evidence is available in the literature to support the use of anticholinergic medications in combination with beta(2)-agonists in acute asthma patients? We limited the search on our therapy question to systematic reviews of randomized trials and/or randomized controlled trials not included in the reviews. After an extensive review of the most relevant evidence, the following conclusions may be emphasized. (1) The use of multiple doses of ipratropium bromide are indicated in the ED treatment of children and adults with severe acute asthma. The studies reported a substantial reduction in hospital admissions (30 to 60%; number needed to treat, 5 to 11) and significant differences in lung function favoring the combined treatment. No apparent increase in the occurrence of side effects was observed. (2) The use of single-dose protocols of ipratropium bromide with beta(2)-agonist treatment produced, particularly in children with more severe acute asthma, a modest improvement in pulmonary function without reduction in hospital admissions; in adults, the data showed a similar increase in pulmonary function with an approximately 35% reduction in the hospital admission rate. In patients with mild-to-moderate acute asthma, there is no apparent benefit from adding a single dose of an anticholinergic medication.

Contemporary approach to the emergency department management of pediatric asthma

Asthma continues to be an enormous health problem and economic burden in US society. EDs probably will continue to provide a substantial amount of care for those affected by the disease. Pediatric asthma patients frequently are encountered in EDs. Emergency physicians must remain current in their approach to providing expert care while the management of acute asthma exacerbations continues to evolve, older therapies are challenged and new therapies are developed, tested, and implemented.

Drugs in pregnancy. Respiratory disease

Respiratory illnesses are the commonest cause of patient visits to physicians. Although the common cold, sinusitis and bronchitis may be lacking in drama, they account for a substantial amount of morbidity among women of reproductive age and are frequently encountered by physicians caring for pregnant women. Present knowledge about the management of these common conditions and the safety of the medications often used to treat them are reviewed in this chapter. Asthma and community-acquired pneumonia are more serious respiratory illnesses that are also often encountered in pregnancy. Present evidence suggests that community-acquired pneumonia is best treated empirically, with additional investigation usually necessary only if there is a failure of initial treatment. The recognition of asthma as an inflammatory condition has led to a very specific approach to its management that can readily and safely be applied to the pregnant woman. Treatment of HIV and tuberculosis should not be withheld during pregnancy because of the life-threatening nature of these infections and the importance of preventing vertical transmission.

The use of ipratropium bromide for the management of acute asthma exacerbation in adults and children: a systematic review

Ipratropium bromide is a quaternary anticholinergic bronchodilator that is commonly used to treat obstructive lung disease. Although ipratropium is not usually employed as a first-line bronchodilator to treat chronic asthma, it has been used extensively in hospital emergency departments as adjunctive therapy for the emergency treatment of acute asthma exacerbation. This review will summarize the physiological actions of ipratropium and the rationale for its use as an anticholinergic bronchodilator. Evidence available from randomized trials and from two meta-analyses is summarized to determine whether the addition of inhaled ipratropium to inhaled beta2-agonist therapy is effective in the treatment of acute asthma exacerbation in children and adults. Published reports of randomized, controlled trials assessing the use of ipratropium and concurrent beta2-agonists in adult acute asthma exacerbation were identified by a search of electronic databases, as well as by hand searching. Data from 10 studies of adult asthmatics, reporting on a total of 1377 patients, were pooled in a meta-analysis using a weighted-average method. Use of nebulized ipratropium/beta2-agonist combination therapy was associated with a pooled 7.3% improvement in forced expiratory volume in 1 sec [95% confidence interval (CI), 3.8-10.9%] and a 22.1% improvement in peak expiratory flow (95% CI, 11.0-33.2%) compared with patients who received beta2-agonist without ipratropium. For the three trials in adults reporting hospital admission data (n = 1064), adult patients receiving ipratropium had a relative risk of hospitalization of 0.80 (95% CI, 0.61-1.06). Similarly, randomized controlled studies of pediatric asthma exacerbation and a meta-analysis of pediatric asthma patients suggest that ipratropium added to beta2-agonists improves lung function and also decreases hospitalization rates, especially among children with severe exacerbations of asthma. The adult and pediatric studies did not report any severe adverse effects attributable to ipratropium when it was used in conjunction with beta2-agonists. In conclusion, there is a modest statistical improvement in airflow obstruction when ipratropium is used as an adjunctive to beta2-agonists for the treatment of acute asthma exacerbation. In pediatric asthma exacerbation, use of ipratropium also appears to improve clinical outcomes; however, this has not been definitively established in adults. It would seem reasonable to recommend the use of combination ipratropium/beta2-agonist therapy in acute asthmatic exacerbation, since the addition of ipratropium seems to provide physiological evidence of benefit without risk of adverse effects.

Pharmacologic treatment of the adult hospitalized asthma patient

Acute severe asthma calls for aggressive and early therapy of a multifaceted and all-inclusive approach (Fig. 2). Therapy merely begins in the ED and manifold distinct issues need to find consideration during ongoing hospital care. Currently, beta-agonists, anti-cholinergic agents, and corticosteroids remain the mainstay of therapy. Methylxanthines and magnesium may find consideration in carefully selected patients. Multiple new therapeutic avenues, such as the anti-leukotriene drugs, seem promising and future studies will hopefully extend our armamentarium against life threatening complication of a common disease. Asthma education begun in the hospital may provide the platform for preventing severe acute exacerbations and hospitalization.

Evaluation and management of patients with pulmonary disease before thoracic and cardiovascular surgery

The risks of respiratory complications after thoracic and cardiovascular surgeries are particularly high for patients with chronic pulmonary disease and are associated with prolonged hospital stays and increased mortality. The primary goals of preoperative management are to identify risk factors and institute interventions likely to reduce subsequent postoperative pulmonary complications. Smoking, symptomatic obstructive lung disease, respiratory infection, obesity, and malnutrition are all potentially modifiable risk factors. Chest physiotherapy is indicated in all patients regardless of risk factor profile. Providing a thoughtfully designed, multifaceted course of preoperative care can result in a clinically significant reduction in postoperative morbidity and mortality, particularly if instituted well in advance of surgery.

Tiotropium bromide

Tiotropium bromide is a new long-lasting anticholinergic drug which, like ipratropium bromide, is a quaternary ammonium derivative. It binds with high affinity to muscarinic receptors but dissociates very slowly from M(1)- and M(3)-muscarinic receptors. Pharmacology studies have demonstrated a prolonged protective effect against cholinergic agonists and cholinergic nerve stimulation in animal and human airways. In Phase II studies single inhaled doses of tiotropium bromide have a bronchodilator and bronchoprotective effect in asthmatic and chronic obstructive pulmonary disease (COPD) patients of over 24 h. In Phase III studies, once daily inhaled tiotropium is an effective bronchodilator in COPD patients, giving great improvement in lung function and reduction in symptoms than ipratropium bromide given four times daily. The drug is well-tolerated and the only side effect of note is dryness of the mouth which occurs in approximately 10% of patients. Since, anticholinergics are the bronchodilators of choice in COPD it is likely that tiotropium bromide will become the most widely used bronchodilator for COPD patients in the future.

Ipratropium bromide plus nebulized albuterol for the treatment of hospitalized children with acute asthma

OBJECTIVE

To determine whether the addition of repeated doses of nebulized ipratropium bromide (IB) to a standardized inpatient asthma care algorithm (ACA) for children with status asthmaticus improves clinical outcome.

STUDY DESIGN

Children with acute asthma (N = 210) age 1 to 18 years admitted to the ACA were assigned to the intervention or placebo group in randomized double-blind fashion. Both groups received nebulized albuterol, systemic corticosteroids, and oxygen according to the ACA. The intervention group received 250 microg IB combined with 2.5 mg albuterol by jet nebulization in a dosing schedule determined by the ACA phase. The placebo group received isotonic saline solution substituted for IB. Progression through each ACA phase occurred based on assessments of oxygenation, air exchange, wheezing, accessory muscle use, and respiratory rate performed at prescribed intervals.

RESULTS

No significant differences were observed between treatment groups in hospital length of stay (P =.46), asthma carepath progression (P =.37), requirement for additional therapy, or adverse effects. Children >6 years (N = 70) treated with IB had shorter mean hospital length of stay (P =.03) and more rapid mean asthma carepath progression (P =.02) than children in the placebo group. However, after adjustment was done for baseline group differences, the observed benefit of IB therapy in older children no longer reached statistical significance.

CONCLUSION

The routine addition of repeated doses of nebulized IB to a standardized regimen of systemic corticosteroids and frequently administered beta-2 agonists confers no significant enhancement of clinical outcome for the treatment of hospitalized children with status asthmaticus.

Asma aguda em adultos na sala de emergência: o manejo clínico na primeira hora

Asma é doença com alta prevalência em nosso meio e ao redor do mundo. Embora novas opções terapêuticas tenham sido recentemente desenvolvidas, parece haver aumento mundial na sua morbidade e mortalidade. Em muitas instituições, as exacerbações asmáticas ainda constituem emergência médica muito comum. As evidências têm demonstrado que a primeira hora no manejo da asma aguda na sala de emergência concentra decisões cruciais que podem determinar o desfecho desta situação clínica. Nesta revisão não-sistemática, os autores enfocaram a primeira hora da avaliação e tratamento do paciente com asma aguda na sala de emergência, descrevendo uma estratégia apropriada para o seu manejo. São consideradas as seguintes etapas: diagnóstico, avaliação da gravidade, tratamento farmacológico, avaliação das complicações e decisão sobre onde se realizará o tratamento adicional. Espera-se que estas recomendações contribuam para que o médico clínico tome a decisão apropriada na primeira hora do manejo da asma aguda.

Experimental drug therapy for respiratory disorders in dogs and cats

Experimental therapy in veterinary medicine is based on empiric reasoning. If a particular therapy is labeled experimental, it means that its effectiveness has not been demonstrated scientifically. Empiric therapy is experimental and is based on experience, not on scientific proof. The purpose of this article is to suggest the use of specific experimental drug therapies for certain respiratory disorders in dogs and cats.

Intravenous magnesium sulfate treatment for acute asthma in the emergency department: a systematic review of the literature

STUDY OBJECTIVES

There is some evidence that magnesium, when infused into asthmatic patients, can produce bronchodilation in addition to that obtained from standard treatments. This systematic review examined the effect of intravenous magnesium sulfate used for patients with acute asthma managed in the emergency department.

METHODS

Only randomized controlled trials were eligible for inclusion. Studies were included if patients presented with acute asthma and were treated with intravenous magnesium sulfate versus placebo. Trials were identified from the Cochrane Airways Review Group register, which consists of a combined search of EMBASE, MEDLINE, and CINAHL databases and hand-searching of 20 key respiratory journals. Bibliographies from included studies and known reviews were searched. Primary authors and content experts were contacted. Data were extracted and methodologic quality was assessed independently by 2 reviewers. Missing data were obtained from authors.

RESULTS

Seven trials (5 adult, 2 pediatric) involving a total of 668 patients were included. Overall, admission to hospital was not statistically reduced using magnesium sulfate (odds ratio [OR] 0.31, 95% confidence interval [CI] 0.09 to 1.02). In the severe subgroup, admissions were reduced in those receiving magnesium sulfate (OR 0.10, 95% CI 0.04 to 0.27). Overall, patients receiving magnesium sulfate demonstrated nonsignificant improvements in peak expiratory flow rates (PEFR) when all studies were pooled (weighted mean difference [WMD] 29 L/min, 95% CI -3 to 62). In studies of patients with severe acute asthma, PEFR WMD improved by 52 L/min (95% CI 27 to 78) favoring magnesium sulfate treatment. The absolute FEV(1) also improved by 10% predicted (95% CI 4 to 16) in patients with severe acute asthma. No clinically important changes in vital signs or side effects were reported.

CONCLUSION

Current evidence does not clearly support routine use of intravenous magnesium sulfate in all patients with acute asthma presenting to the ED. However, magnesium sulfate appears to be safe and beneficial for patients who present with severe acute asthma. Practice guidelines need to be changed to reflect these results.

Efficacy of adding multiple doses of oxitropium bromide to salbutamol delivered by means of a metered-dose inhaler with a spacer device in adults with acute severe asthma

BACKGROUND

The efficacy of combination therapy adding multiple doses of anticholinergics to beta(2)-agonists to improve outcome has not been established in adults with acute severe asthma.

OBJECTIVE

This study was undertaken to compare the outcome of adults with acute severe asthma treated with 4 puffs of salbutamol (100 microg/actuation) every 20 minutes for 3 doses plus 4 puffs of oxitropium bromide (100 microg/actuation) with each of the 3 salbutamol doses versus salbutamol alone administered by means of a metered-dose inhaler with a spacer device.

METHODS

A randomized, single-blind, placebo-controlled study was performed in 74 patients between 18 and 55 years old presenting to the emergency department (ED) for treatment of acute asthma with a peak expiratory flow (PEF) of 50% or less than the normal predicted value. The primary endpoint was improvement in PEF over the course. The secondary endpoint was the need for additional ED treatment at 120 minutes.

RESULTS

The increase in PEF over the course was significantly greater in the oxitropium plus salbutamol treatment group (P <.0001). The mean absolute difference in PEF at 120 minutes for combination therapy compared with salbutamol alone was 37.8 L/min (P =.001). In addition, the proportion of need for additional ED treatment was less in the combination group than the group receiving salbutamol alone (odds ratio, 0.32; 95% confidence interval, 0.11-0.90).

CONCLUSION

Adding multiple doses of oxitropium bromide to salbutamol delivered by means of a metered-dose inhaler with a spacer device for acute severe asthma produces a significant improvement in lung function and reduces the need for additional ED treatment.

State of the art: therapeutic controversies in severe acute asthma

This is a transcript of the 1999 SAEM State-of-the-Art session on "Therapeutic Controversies in Severe Acute Asthma," presented at the 1999 SAEM annual meeting in Boston. The aim of this session was to address some of the current controversies in the management of acute asthma exacerbations, a major issue in emergency medicine. Despite many recent advances in asthma management, morbidity and mortality remain high. While many of us have strong feelings on how asthma patients should be treated, many of our assertions are not based on good science, and there are numerous areas of controversy. This discussion focuses on the controversy over beta agonist treatment for acute asthma, the physiology of corticosteroids in asthma, and the emergency use of leukotriene-modifying agents.

First-line therapy for adult patients with acute asthma receiving a multiple-dose protocol of ipratropium bromide plus albuterol in the emergency department

We designed a larger, double-blind, randomized, prospective trial to test our hypothesis that patients with acute asthma given combination high dose therapy with ipratropium bromide (IB) and beta(2)-agonists will have greater improvement in pulmonary function and fewer hospital admissions than those given beta(2)-agonists alone. One hundred eighty patients (mean age +/- SD, 34.3 +/- 10.5 yr) who presented to an emergency department (ED) for treatment of an exacerbation of asthma (baseline FEV(1) < 50% of predicted) were assigned in a randomized, double-blind fashion to receive albuterol and placebo (n = 92) or albuterol and IB (n = 88). Both drugs were administered through a metered-dose inhaler and spacer at 10-min intervals for 3 h (24 puffs or 2,880 microg of albuterol and 504 microg of IB each hour). Primary outcome measures were improvement in pulmonary function (FEV(1) or peak expiratory flow [PEF]), and hospital admission rates. In both groups, pulmonary function improved significantly over baseline values (p < 0.01). Subjects who received IB had an overall 20.5% (95% CI: 2.6 to 38.4%) (p = 0.02) greater improvement in PEF and a 48.1% (95% CI: 19.8 to 76.4%) (p = 0.001) greater improvement in FEV(1) from the control group. At the end of protocol (3 h), 39% (n = 36) of patients in the control group and 20% (n = 18) in the IB group were admitted (p = 0.01). The use of high doses of IB reduced the risk of hospital admission 49% (relative risk = 0.51, 95% CI: 0.31 to 0.83). Five (95% CI: 3 to 17) patients would need to be treated with high doses of IB to prevent a single admission. Kaplan-Meier-estimated curves of the proportion of patients who reached the discharge threshold during the 3 h of treatment, showed a significant difference in favor of the IB group (log-rank test = 0.005). A subgroup analysis showed that patients most likely to benefit from the addition of high doses of IB were those with more severe obstruction (FEV(1) </= 30% of predicted) and long duration of symptoms before the ED presentation (>/= 24 h). On the contrary, previous use of inhaled beta(2)-agonists did not modify the admission rate and the pulmonary function response to IB. In conclusion, our data support a substantial therapeutic benefit from the addition of IB to albuterol administered in high doses through MDI plus spacer, particularly in patients with FEV(1) less than 30%, and with long duration of symptoms before the ED presentation (>/= 24 h).

Treatment of acute asthma. A new look at the old and at the new

beta-Agonists remain the mainstay of therapy for acute asthma and, for most patients, standard doses are acceptable. Although the onset of action of systemic steroids is still not clear, steroids promote recovery and should be given to patients with acute illness. Intravenous magnesium sulfate appears to improve pulmonary function in the most severely ill patients but is not useful in patients with more moderate episodes. Ipratropium bromide is a weak bronchodilator that still needs to be tested as an adjunct to standard treatment regimens before its role in adults with asthma can be determined; given its ease of use and favorable safety profile it could be considered for patients with more severe acute illness. Aminophylline has not been found by most studies to improve outcomes and the narrow therapeutic range and unfavorable safety profile relegate it to a last-line agent or no use at all. Helium-oxygen mixtures currently have no role in moderately ill patients but have a theoretical advantage as a temporizing measure in severely ill patients. Drugs used in the management of chronic asthma, such as inhaled steroids and leukotriene-modifying agents, are making their way into the acute treatment arena, and other newly developed specific mediator inhibitors or blockers deserve attention. The use of isomers of beta-agonists is another area that is attracting attention and study. Systemic steroids are used to prevent relapse after emergency department discharge and the addition of other agents such as leukotriene-modifying agents or inhaled steroids may further prevent the need for urgent visits or hospitalization. The search for optimal treatment strategies for acutely ill patients is challenging and exciting and, with more attention and resources being devoted to this area, newer treatments will be found that will eventually have a greater impact on the high morbidity associated with acute asthma.

Management of respiratory failure in patients with asthma

The goal of management of patients with respiratory failure is to restore them to a state of quiet breathing, without complication. This goal is often achieved by pharmacotherapy alone. Inhaled albuterol sulfate, oxygen, and systemic corticosteroids are mainstays of acute care drug management, whereas other data support the use of inhaled steroids, ipratropium bromide, magnesium sulfate, theophylline, and heliox. Assisted ventilation by face mask or endotracheal tube may be required in refractory patients. In intubated patients, a ventilatory strategy that prolongs exhalation time and accepts hypercapnia minimizes lung hyperinflation and generally results in a good outcome. Acute asthma often represents failure of outpatient management; key aspects of the outpatient program should be addressed in the acute care setting to help prevent recurrent attacks.

Systematic reviews: a logical methodological extension of evidence-based medicine

Academic Emergency Medicine is interested in publishing systematic reviews (also known as meta-analyses) containing explicit, quantitative compilations of valid, critically appraised evidence targeted at topics relevant to the science and practice of emergency medicine. This article presents a strategy for the performance and reporting of systematic reviews, based on established recommendations. A well-performed systematic review of the literature may provide clinically relevant information otherwise unobtainable, and has potential to alter patient care. Systematic reviews are logical methodological extensions of evidence-based medicine.