Does aminophylline benefit adults admitted to the hospital for an acute exacerbation of asthma?

Efficacy and side effects of intravenous theophylline in acute asthma: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Theophylline has been used for decades to treat both acute and chronic asthma. Despite its longevity in the practitioner's formulary, no detailed meta-analysis has been performed to determine the conditions, including concomitant medications, under which theophylline should be used for acute exacerbations of asthma. We aimed to quantify the usefulness and side effects of theophylline with or without ethylene diamine (aminophylline) in acute asthma, with particular emphasis on patient subgroups, such as children, adults, and concomitant medications.

METHODS

We searched PubMed, EMBASE, The Cochrane Library, ClinicalTrials.gov, and the WHO Clinical Trials Registry for randomized, controlled clinical trials. We planned a priori subgroup analyses by time post-medication, concomitant medication, control type, and age.

RESULTS

We included 52 study arms from 42 individual trials. Of these, 29 study arms included an active control, such as adrenaline, beta-2 agonists, or leukotriene receptor antagonists, and 23 study arms compared theophylline (with or without ethylene diamine) with placebo or no drug. Theophylline significantly reduced heart rate when compared with active control (p=0.01) and overall duration of stay (p=0.002), but beta-2 agonists were superior to theophylline at improving forced expiratory volume in one second (FEV1) (p=0.002). Theophylline was not significantly different from other drugs in its effects on respiratory rate, forced vital capacity (FVC), peak expiratory flow rate, admission rate, use of rescue medication, oxygen saturation, or symptom score. Closer examination of the data revealed that the medications given in addition to theophylline or control significantly changed the effectiveness of theophylline (subgroup difference: p<0.00001).

CONCLUSION

Given the low cost of theophylline, and its similar efficacy and rate of side effects compared with other drugs, we suggest that theophylline, when given with bronchodilators with or without steroids, is a cost-effective and safe choice for acute asthma exacerbations.

Addition of intravenous aminophylline to inhaled beta(2)-agonists in adults with acute asthma

BACKGROUND

Asthma is a chronic condition in which sufferers may have occasional or frequent exacerbations resulting in visits to the emergency department (ED). Aminophylline has been used extensively to treat exacerbations in acute asthma settings; however, it's role is unclear especially with respect to any additional benefit when added to inhaled beta(2)-agonists.

OBJECTIVES

To determine the magnitude of effect of the addition of intravenous aminophylline to inhaled beta(2)-agonists in adult patients with acute asthma treated in the ED setting.

SEARCH METHODS

We identified trials from the Cochrane Airways Group register (derived from MEDLINE, EMBASE, CINAHL standardised searches) and handsearched respiratory journals and meeting abstracts. Two independent review authors screened and obtained potentially relevant articles and handsearched their bibliographic lists for additional articles. In the original version of this review published in 2000 we included searches of the database up to 1999. The 2012 review was updated with a revised search from inception to September 2012.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous aminophylline versus placebo in adults with acute asthma and treated with inhaled beta(2)-agonists. We included patients who were treated with or without corticosteroids or other bronchodilators provided this was not part of the randomised treatment.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data and one review author entered data into RevMan, which was checked by a second review author. Results are reported as mean differences (MD) or odds ratios (OR) with 95% confidential intervals (CI).

MAIN RESULTS

Fifteen studies were included in the previous version of the review, and we included two new studies in this update, although we were unable to pool new data. Overall, the quality of the studies was moderate; concealment of allocation was assessed as clearly adequate in only seven (45%) of the trials. There was significant clinical heterogeneity between studies as the doses of aminophylline and other medications and the severity of the acute asthma varied between studies.There was no statistically significant advantage when adding intravenous aminophylline with respect to hospital admissions (OR 0.58; 95% CI 0.30 to 1.12; 6 studies; n = 315). In 2000 it was found that there was no statistically significant effect of aminophylline on airflow outcomes at any time period; the addition of two trials in 2012 has not challenged this conclusion. People treated with aminophylline and beta(2)-agonists had similar peak expiratory flow (PEF) values compared to those treated with beta(2)-agonists alone at 12 h (MD 8.30 L/min; 95% CI -20.69 to 37.29 L/min) or (MD -1.21% predicted; 95% CI -14.21% to 11.78% predicted) and 24 h (MD 22.20 L/min; 95% CI -56.65 to 101.05 L/min). Two subgroup analyses were performed by grouping studies according to mean baseline airflow limitation (11 studies) and the use of any corticosteroids (nine studies). There was no relationship between baseline airflow limitation or the use of corticosteroids on the effect of aminophylline. Aminophylline-treated patients reported more palpitations/arrhythmias (OR 3.02; 95% CI 1.15 to 7.90; 6 studies; n = 249) and vomiting (OR 4.21; 95% CI 2.20 to 8.07; 7 studies; n = 321); however, no significant difference was found in tremor (OR 2.60; 95% CI 0.62 to 11.02; 5 studies; n = 249).

AUTHORS' CONCLUSIONS

The use of intravenous aminophylline did not result in significant additional bronchodilation compared to standard care with inhaled beta(2)-agonists in patients experiencing an asthma exacerbation in the ED setting, or in a significant reduction in the risk of hospital admission. For every 100 people treated with aminophylline an additional 20 people had vomiting and 15 people arrhythmias or palpitations. No subgroups in which aminophylline might be more effective were identified. Our update in 2012 is consistent with the original conclusions that the risk-benefit balance of intravenous aminophylline is unfavourable.

Aminophylline for treating asthma and chronic obstructive pulmonary disease

Aminophylline is a complex of theophylline and ethylenediamine. Its main pharmacological action is relaxation of bronchial smooth muscle. Two meta-analyses examining the efficacy of aminophylline in acute asthma attacks in children and in adults have been reported by the Cochrane Collaboration. In the meta-analysis reporting results from studies in children, it was concluded that aminophylline does not add any benefit to standard care. Yet one study, which has the largest patient population, reports that aminophylline improves lung functions within 6-8 h and reduces the risk of intubation. The meta-analysis examining adult studies revealed that there is no outstanding difference between aminophylline and standard therapy in the management of adult acute asthma. In conclusion, aminophylline may be an alternative to intravenous infusion of beta-agonists, heliox or magnesium sulfate administration in children in whom respiratory fatigue begins to develop and intensive-care unit admission and mechanical ventilation seems to be the next treatment in line. However, in adults, it is not recommended for use in the treatment of acute asthma owing to its possible adverse effects.

Efficacy and safety of intravenous theophylline administration for treatment of mild acute exacerbation of bronchial asthma

OBJECTIVE

The present study was designed to evaluate the efficacy and safety of intravenously administered theophylline (IAT) for the treatment of an acute exacerbation of bronchial asthma. The theophylline was solubilized and not combined with ethylenediamine.

METHODOLOGY

The subjects were 22 asthmatic patients with mild acute exacerbation of bronchial asthma. All patients had been taking oral sustained-release theophylline and their serum concentrations of theophylline were measured. The 16 patients whose serum theophylline concentrations were <13 microg/mL were randomly selected and treated with IAT (200 mg theophylline in 200 mL saline) for 2 h. Six patients were randomly selected as controls and received 200 mL of saline. Pulmonary function and asthma severity (Borg scale) before and after treatment were measured.

RESULTS

After IAT, both PEF (before IAT, 313+/-79 L/min; after IAT, 335+/-107; P<0.05) and FEV(1) (before IAT, 1.66+/-0.47 L; after IAT, 1.83+/-0.44; P<0.05) increased significantly. Furthermore, their severity of asthma as assessed by the Borg scale (before IAT, 2.5+/-1.2; after IAT, 1.3+/-1.0; P<0.05) improved significantly. In contrast, neither FEV(1), PEF, severity of asthma or Borg scale changed significantly in the group who only received saline. None of the patients treated in this study had any adverse effects.

CONCLUSION

These results suggest that IAT is useful for patients with mild acute exacerbation of bronchial asthma and is safe if serum theophylline concentrations are measured.

Aminophilline suppress the release of chemical mediators in treatment of acute asthma

BACKGROUND

The control of airway inflammation is crucial for management of asthma. Theophylline has been demonstrated to have an anti-inflammatory effect as a long-term-medication for asthma in various studies. In the present study we attempted to clarify if aminophylline, a theophylline derivative, could act as an anti-inflammatory agent as well as a bronchodilator in the treatment for acute asthma exacerbations.

METHODS

Patients are initially treated either with an intravenous infusion of aminophylline or with inhalation of salbutamol. Pro-inflammatory mediators such as eosinophil cationic protein (ECP), histamine, serotonin, thromboxane B2, leukotriene C4 were measured before and one hour after the initial treatment. Clinical parameters such as peak expiratory flow (PEF) and SpO2 were also checked during the studies.

RESULTS

Significant improvements of PEF and SpO2 with both aminophylline and salbutamol treatment were seen. Furthermore, significant decreases of ECP, histamine, and serotonin were observed with aminophylline but not with salbutamol.

CONCLUSIONS

Suppressing the release of pro-inflammatory mediators may play a role, at least in part, in the beneficial effects of aminophylline in the treatment of acute exacerbations in asthma. Additionally, this study indicated that treatment with aminophylline is at least as beneficial as nebulized salbutamol in the restoration of lung function.

Severe exacerbations of asthma

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

Reassessment of theophylline use for severe asthma exacerbation: is it justified in critically ill hospitalized patients?

In the 1990s, numerous double-blind, randomized, placebo-controlled trials revealed that theophylline therapy offered no benefit to inhaled beta2 agonists and systemic corticosteroids in the treatment of patients hospitalized for asthma exacerbations. Routine use of theophylline in patients hospitalized for asthma is no longer advocated due to the potential for serious adverse effects and lack of benefit. However, the question remains whether this drug adds any benefits in critically ill patients who are being admitted to an intensive care unit. Two recent pediatric studies suggest that theophylline therapy may have a role in the management of patients with impending respiratory failure who have failed aggressive treatment with inhaled beta2 agonists, systemic corticosteroids, and inhaled ipratropium. If a patient has failed to respond adequately to high-dose routine therapies, theophylline should be initiated by a clinician who is competent in dosing, monitoring serum concentrations, and assessing factors that modify clearance of this high-risk drug. Further clinical research is needed to verify the value of theophylline in adults and children with severe asthma exacerbations and impending respiratory failure.

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.

Efficacy of IV theophylline in children with severe status asthmaticus

STUDY OBJECTIVE

To determine whether adding IV theophylline to an aggressive regimen of inhaled and IV beta-agonists, inhaled ipratropium, and IV methylprednisolone would enhance the recovery of children with severe status asthmaticus admitted to the pediatric ICU (PICU).

DESIGN

A prospective, randomized, controlled trial. Asthma scoring was performed by investigators not involved in treatment decisions and blinded to group assignment.

SETTING

The PICU of an urban, university-affiliated, tertiary-care children's hospital.

PATIENTS

Children with a diagnosis of status asthmaticus who were admitted to the PICU for < or = 2 h and who were in severe distress, as indicated by a modified Wood-Downes clinical asthma score (CAS) of > or = 5.

INTERVENTIONS

All subjects initially received continuous albuterol nebulizations; intermittent, inhaled ipratropium; and IV methylprednisolone. The theophylline group was also administered infusions of IV theophylline to achieve serum concentrations of 12 to 17 microg/mL. A CAS was tabulated twice daily.

MEASUREMENTS AND RESULTS

Forty-seven children (median age, 8.3 years; range, 13 months to 17 years) completed the study. Twenty-three children received theophylline. The baseline CASs of both groups were similar and included three subjects receiving mechanical ventilation in each group. All subjects receiving mechanical ventilation and theophylline were intubated before drug infusion. Among the 41 subjects who were not receiving mechanical ventilation, those receiving theophylline achieved a CAS of < or = 3 sooner than control subjects (18.6 +/- 2.7 h vs 31.1 +/- 4.5 h; p < 0.05). Theophylline had no effect on the length of PICU stay or the total incidence of side effects. Subjects receiving theophylline had more emesis (p < 0.05), and control patients had more tremor (p < 0.05).

CONCLUSIONS

Theophylline safely hastened the recovery of children in severe status asthmaticus who were also receiving albuterol, ipratropium, and methylprednisolone. The role of theophylline in the management of asthmatic children in impending respiratory failure should be reexamined.

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.

Efficacy of IV aminophylline as a supplemental therapy in moderate broncho-obstructive crisis in infants and preschool children

The aim of the present study was to investigate the efficacy of iv aminophylline as a supplemental therapy for wheezy infants and preschool children who still present moderate broncho-obstruction after treatment with nebulized fenoterol. A prospective randomized, double blind, placebo-controlled trial was conducted in a Paediatric Emergency Room. The major selection criteria for patients>> inclusion were age between 1 and 7 years, a wheezy episode lasting less than 2 days which failed to respond to three sequential fenoterol nebulizations, a Wood-Downes score between 3 and 6, and a history of at least two similar episodes. Exclusion criteria were radiologically-identified pulmonary condensation, recent use of corticosteroid and/or theophylline drugs, and previous diagnosis of chronic conditions. A sample of 43 cases was selected: 24 in Group A and 19 in Control Group B. All patients were submitted to nebulization with fenoterol and intravenous hydrocortisone for a maximum period of 24 h. Only Group A patients received iv aminophylline (6 mg/kg in bolus and 1.2 mg/kg per h for maintenance schedule). Treatment efficacy parameters established for the two groups were based on the Wood-Downes clinical score. Throughout the study, the average clinical scores and the discharge rate were similar for both groups. The average stay in the Emergency Room was 12.5 h for Group A and 14.6 h for Control Group B. In conclusion, the use of supplemental iv aminophylline for moderate broncho-obstructive crisis in wheezy infants and preschool children did not add therapeutically significant results to the usually prescribed combination of nebulized beta-adrenergic and intravenous corticosteroid drugs.

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.

Addition of intravenous aminophylline to beta2-agonists in adults with acute asthma

BACKGROUND

Aminophylline has been used extensively in acute asthma, but its role is unclear especially with respect to any additional benefit when added to beta2-agonists.

OBJECTIVES

To determine the magnitude of effect of the addition of intravenous aminophylline to beta2-agonists in adult patients with acute asthma treated in the emergency setting.

SEARCH STRATEGY

Studies were identified from the following sources: The Cochrane Airways Group register (derived from MEDLINE, EMBASE, CINAHL standardised searches), hand searched respiratory journals and meeting abstracts. Potentially relevant articles were obtained, and their bibliographic lists were hand searched for additional articles. The search included searches of the database up to 1999.

SELECTION CRITERIA

Randomised controlled trials comparing intravenous aminophylline versus placebo in adults with acute asthma and treated with beta-adrenergic agonists. Patients could be treated with or without corticosteroids or other bronchodilators.

DATA COLLECTION AND ANALYSIS

A total of 210 abstracts were identified. Two independent reviewers selected a total of 27 eligible studies for possible inclusion, in which quality assessment was performed and a third reviewer was used to adjudicate disagreements. Peak expiratory flow (PEFR) and forced expiratory volume in the first second (FEV1) data were extracted and entered in Review Manager from these studies. Information not obtained from the authors was estimated from graphs. All data were entered and double checked by two reviewers. Results are reported as weighted mean differences (WMD) or odds ratio (OR), both with 95% confidential intervals (CI).

MAIN RESULTS

Fifteen trials were included. Overall, the quality of the studies was only moderate; concealment of allocation was assessed as clearly adequate in only seven (45%) of the trials. The doses of aminophylline and other medications and the severity of asthma varied between studies. There was no statistically significant effect of aminophylline on airflow outcomes at any time period. The aminophylline treated group had higher values of PEFR at 12 (PEFR 8 L/min or 2.3%) and 24 hours (PEFR 22 L/min or 6.4%), but these were not significant (p>0.05). Two subgroup analyses were performed by grouping studies according to mean baseline airflow limitation (n = 11 studies) and the use of any steroids (n = 9 studies). There was no relationship between baseline airflow limitation nor the use of steroids on the effect of aminophylline. Aminophylline treated patients reported more palpitations/arrhythmias (OR: 2.9; 95% CI: 1.5 to 5.7) and vomiting (OR: 4.2; 95% CI 2.4 to 7.4), but no difference was found in tremor or hospital admissions.

REVIEWER'S CONCLUSIONS

In acute asthma, the use of intravenous aminophylline did not result in any additional bronchodilation compared to standard care with beta-agonists. The frequency of adverse effects was higher with aminophylline. No subgroups in which aminophylline might be more effective could be identified. These results should be added to consensus statements and guidelines.

[Importance of other therapeutic medications administered parenterally in severe acute asthma]

Following definition of severity criteria for asthmatic crisis, the effects of various drugs are analyzed: inhaled isoproterenol, inhaled metaproterenol alone or in combination with theophylline, inhaled albuterol, intravenous salbutamol, theophylline in severe acute asthma, corticosteroids in very severe acute asthma. In conclusion, nebulized beta agonists often administered in combination with atropinic drugs represent the best therapy for moderate acute asthma.

Randomised controlled trial of aminophylline for severe acute asthma

OBJECTIVES

To determine whether children with severe acute asthma treated with large doses of inhaled salbutamol, inhaled ipratropium, and intravenous steroids are conferred any further benefits by the addition of aminophylline given intravenously.

STUDY DESIGN

Randomised, double blind, placebo controlled trial of 163 children admitted to hospital with asthma who were unresponsive to nebulised salbutamol.

RESULTS

The placebo and treatment groups of children were similar at baseline. The 48 children in the aminophylline group had a greater improvement in spirometry at six hours and a higher oxygen saturation in the first 30 hours. Five subjects in the placebo group were intubated and ventilated after enrollment compared with none in the aminophylline group.

CONCLUSIONS

Aminophylline continues to have a place in the management of severe acute asthma in children unresponsive to initial treatment.

Severe acute asthma in a community hospital pediatric intensive care unit: a ten years' experience

BACKGROUND

The clinical literature on the incidence and subsequent mortality of asthma has come primarily from the experiences of large tertiary referral centers, particularly in Western Europe and North America. Consequently, very little has been published on the incidence, management, and outcome of asthma in smaller, community-based intensive care units.

OBJECTIVES

The purpose of this study was to explore the course and outcome of children with acute severe asthma treated within a community hospital PICU compared with those described in the literature from larger tertiary referral centers.

DESIGN

A retrospective analysis of 49 asthmatic children admitted to the Pediatric Intensive Care Unit (PICU) over a 10-year period was performed.

MEASUREMENTS AND RESULTS

The mean age was 5.2 years (range 2 months to 16 years), and the male:female ratio was 3:1. Duration of symptoms prior to admission to hospital was less than 24 hours in 60.4% of the patients. The majority of patients was not treated with either inhaled or oral steroids before admission. Drugs used in the PICU included nebulized beta2-agonists, theophylline, steroids, intravenous salbutamol, and intravenous isoproterenol. Although a pharmacologic approach was successful in the majority of patients, intubation and mechanical ventilation were necessary for progressive hypercapnea, exhaustion, and cardiorespiratory arrest in 11/49 of these patients. The average stay in the ICU for our patient group was 2.4 days. Intubated patients had a mean average stay of 3.5 days. Two patients had pneumothorax related to positive pressure ventilation, requiring chest tube insertion for drainage. There were no deaths among the 49 patients admitted to our PICU.

CONCLUSIONS

These data show that for acute severe asthma, outcome is comparable in a community PICU to a tertiary referral institution. We conclude that early ICU admission along with close monitoring is important in reducing morbidity and mortality in children with severe asthma.

Early parenteral corticosteroid administration in acute asthma

To test the hypothesis that early parenteral corticosteroid administration may be associated with a rapid improvement in airflow obstruction in adult asthmatic patients, a randomized, double-blind placebo-controlled study was carried out. Forty-five adult asthmatic patients, with initial peak expiratory flow rates (PEFRs) of < 200 L/sec received an intravenous bolus of either 125 mg methylprednisolone (MP) or normal saline before any other emergency department treatments. This was immediately followed by 3 aerosol treatments of 2.5 mg of albuterol separated by 20-minute intervals. PEFRs and heart rates were measured over a 1-hour time frame. There was not a significantly higher rate of increase of PEFR in the MP group compared with the saline group. Similarly, the rate of increase in percent PEFR showed a trend to being higher in the saline group (P = .061). There was no significant difference in the proportion of hospitalizations and side effects between the two groups. Adjustment for other variables did not result in a model showing an enhanced PEFR improvement with MP treatment. This study does not support the concept that corticosteroid treatment effects are beneficial within the first hour after administration. Further studies of rapid-acting modalities to enhance bronchodilation are needed in treating acute asthmatics.

The effects of the combination of inhaled ipratropium and oral theophylline in asthma

BACKGROUND

In comparison to beta-agonist drugs, which are the primary bronchodilator drugs in current use in asthma, both oral theophylline and inhaled ipratropium have a weaker bronchodilating action in asthma. Although a number of studies have shown an additive effect of ipratropium in combination with beta-agonist bronchodilator drugs in asthmatics, to our knowledge, the effects of combined treatment with ipratropium and theophylline have not been assessed.

STUDY OBJECTIVE

To assess whether the combination of oral theophylline and inhaled ipratropium has an additive bronchodilator effect in asthmatics.

DESIGN

Double-blind, placebo-controlled, crossover study.

SUBJECTS

Nineteen patients (8 male, 11 female) with mild-to-moderate stable asthma.

METHODS

Initially the optimal single oral dose of theophylline required to achieve therapeutic blood levels (10 to 20 microg/mL) was established in each patient. They then returned at varying intervals on 4 subsequent days. On each day, they received, in a random, placebo-controlled, double-blind, crossover design, one of four different therapies: oral and inhaled placebo; oral theophylline at the established optimal dose (range, 300 to 700 mg) plus inhaled placebo; oral placebo plus inhaled (40 microg) ipratropium; and the combination of theophylline and ipratropium. Spirometry was performed at baseline and at 15 min, 30 min, and hourly intervals for 6 h after therapy.

RESULTS

Each drug regimen resulted in a significant (p<0.05) increase in FEV1, but the combined regimen resulted in a significantly greater bronchodilation (p<0.05) over either ipratropium or theophylline alone (FEV1=3.00+/-0.75 L vs 2.48+/-0.77 L vs 2.61+/-0.72 L, respectively, at 3 h postdrug).

CONCLUSIONS

There was a significant, early, sustained additive bronchodilator effect of the combination therapy; there were no untoward side effects. These findings indicate that the addition of inhaled ipratropium to oral theophylline provides greater bronchodilation than either drug alone and may be a useful therapeutic modality in asthma.

Alternatives to Standard Status Asthmaticus Therapy

Even with the currently available treatment, morbidity and mortality from asthma continues to rise. Patients with status asthmaticus who do not respond to standard therapy are at risk for respiratory failure and possible mechanical ventilation. Treatment options for refractory status asthmaticus remain limited and alternative and controversial therapies may need to be considered. Alternative therapies include continuous nebulized beta-agonists, ipratropium bromide, intravenous magnesium sulfate, ketamine, or heliox. Morbidity and mortality may be decreased by increased utilization of these alternative therapies. Pharmacists can play a key role in monitoring and recommending new and alternate therapies.

Treatment of severe respiratory failure during status asthmaticus in children and adolescents using high flow oxygen and sodium bicarbonate

OBJECTIVE

Status asthmaticus with respiratory failure is a potentially fatal complication of bronchial asthma. To prevent a fatality in status asthmaticus with respiratory failure, treatment with intravenous isoproterenol or mechanical ventilation has been advocated. These interventions also have serious potential complications, however, and while continuous inhalation of beta agonists has shown promise, the optimal therapy of severe status asthmaticus remains unclear. This paper describes our experience with a treatment protocol used in status asthmaticus with respiratory failure that seeks to avoid intravenous isoproterenol or assisted ventilation.

STUDY DESIGN

Case series of pediatric intensive care patients with severe respiratory failure due to status asthmaticus. Six children and adolescents experienced a total of nine episodes of severe respiratory failure due to status asthmaticus.

RESULTS

In seven of the nine episodes the patients were managed without either intravenous isoproterenol or mechanical ventilation. Hypercarbia persisted for an average of 25 hours (range 17 to 40 hours) in these seven episodes. All subjects recovered without notable sequelae. In two episodes, clinical and blood gas deterioration led to mechanical ventilation. Ventilation was required for 112 and 42 hours, respectively, in these episodes and the patients developed either pneumothorax or pneumomediastinum during ventilation.

CONCLUSION

Using a protocol initiated in 1978 for correction of hypoxia and acidemia, many patients with severe respiratory failure from status asthmaticus can be treated without isoproterenol or mechanical ventilation. Since those treatments have significant risks, consideration should be given to this intervention before resorting to them.

Drug treatment of asthma in the elderly

Asthma is a chronic inflammatory disease of the airways that may affect individuals at any age, and can be especially challenging to diagnose and treat in the elderly. The hallmarks of asthma--bronchial hyperreactivity and reversible airflow obstruction--lead to symptoms of intermittent wheezing, dyspnoea and cough. Occasionally, atypical symptoms such as chest pain or tightness occur and may mimic other diseases more common in the elderly, such as ischaemic heart disease. It is therefore important to use objective measures such as spirometry or bronchoprovocation testing to make a diagnosis. In recent years, trends in the treatment of asthma have changed from reliance on shorter-acting bronchodilating drugs to long term preventative therapy with inhaled corticosteroids. In some elderly asthmatic patients, symptoms may be mild and intermittent, and treatment with an inhaled beta 2-adrenergic agent may be all that is required. Most, however, experience persistent symptoms, and pharmacological therapy should begin with daily inhaled corticosteroids and be increased in a stepwise fashion according to the patient's needs. In such patients, short-acting beta 2-agonists should be continued as needed for acute symptomatic relief. Longer-acting beta 2-agonists, oral theophylline and inhaled anticholinergic therapy may be useful. When symptoms are more severe and potentially life-threatening, oral corticosteroids should be given. Since elderly patients are more likely to develop complications of asthma therapy and more likely to manifest adverse interactions with other therapeutic agents, more intense monitoring of asthma treatment is required in dealing with this population.

The use of beta 2-adrenoceptor agonists in the treatment of bronchial asthma

All guidelines recommend short-acting inhaled beta 2-adrenoceptor agonists as the first-line drugs in acute asthma attacks and inhaled corticosteroids as the drugs of choice when regular daily treatment is needed. Short-acting inhaled beta 2-adrenoceptor agonists are not effective in reducing nocturnal awakenings because of their short duration of action. In addition there has been an intense debate about the regular use of these drugs. This debate is reviewed. They should only be used on "as needed basis". The Swedish guidelines for the treatment of asthma were the first to recommend the new long-acting inhaled beta 2-adrenoceptor agonists at relatively early stage of the illness (800 micrograms daily of inhaled corticosteroids). Two recently completed large multicentre studies with salmeterol in asthmatics support this opinion. Both studies showed a better asthma control with a combination of a low inhaled steroid dose and salmeterol compared to a doubling of the steroid dose. In most asthmatic patients, still symptomatic on inhaled steroids doses 400 to 800 micrograms daily, a test of the addition of inhaled salmeterol is recommended. The steroid dose can be kept low and safe. However, asthmatic patients with either frequent or severe exacerbations should primarily have their steroid dose increased.

Protocol therapy for acute asthma: therapeutic benefits and cost savings

BACKGROUND

To evaluate the therapeutic and financial benefits of protocol therapy for acute asthma using standard medications.

MATERIALS AND METHODS

This study employed a sequential design in which the influence of an asthma care path on hospital admissions, length of stay (LOS) in the emergency department, and return visits were evaluated for 1 year. This information was contrasted with similar data obtained from the 8 months immediately before the protocol was implemented (preprotocol) and a 12-month period after strict adherence to it had declined (admixture).

RESULTS

In all, 526 acute exacerbations of asthma were treated with the care path, and 429 and 558 episodes were evaluated during the preprotocol and admixture periods, respectively. There were no significant differences between the presenting clinical or physiologic features of any group. With the protocol, 77% of the patients resolved their symptoms within 1:47 +/- 0.02 hours:minutes of arrival in the emergency department with a 2% return rate within 24 hours. The algorithms used quickly identified those needing hospitalization. Patients not meeting the criteria for discharge after receiving the treatments employed typically did not resolve their symptoms for days (average hospital stay 4.1 +/- 0.2 days). Compared with the preprotocol period, the care path significantly reduced the LOS by 50 minutes, the number of urgent and intensive care unit admissions by 27% and 41%, respectively, and the frequency of return visits within 24 hours by 66%. Charges to patients and third-party payors decreased $395,000. When adherence to the protocol diminished, LOS, admissions, and returns rose significantly toward preprotocol values and the financial benefits were lost.

CONCLUSIONS

Asthma protocol therapy, based primarily upon aggressive use of sympathomimetics in association with serial monitoring of key indices of improvement, provides prompt and efficient relief for acute exacerbations of asthma. Such an approach yields significant financial benefit while quickly identifying individuals who require hospitalization, and it also detects physician practice patterns that can have potentially detrimental impacts on patient care.

Therapeutic controversies in the treatment of asthma

OBJECTIVE

To introduce readers to the current controversial topics in the area of asthma therapy. Background is provided such that clinicians are aware of these issues and can make rational decisions.

DATA SOURCES

Pertinent articles were individually identified and reviewed from each journal.

STUDY SELECTION

Relevant studies, determined by topic and other specific criteria, e.g., testing methodology, were included.

DATA SYNTHESIS

Further investigation is required in the areas discussed. Systemic effects, specifically growth suppression (in children), adrenal suppression, and osteoporosis, have been demonstrated with high-dose inhaled glucocorticoids; however, the clinical relevance of such intravenous glucocorticoid formulations via nebulizer have not been demonstrated. Likewise, data on the equivalence of the inhaled glucocorticoids, with regard to efficacy and potential systemic effects, and the differences between metered-dose inhalers and dry powder inhalers, with regard to aerosol characteristics and drug delivery, are unclear. Theophylline, when used with inhaled beta-adrenergic agonists and systemic glucocorticoids for the treatment of acute asthma, as not been shown to provide clear benefit and may result in increased adverse effects. The use of regular (vs. "as needed" or prn) inhaled beta-adrenergic agonists, although shown in two studies to be detrimental to the control of asthma and result in an increased risk of death or near death caused by asthma, has not been conclusively demonstrated to be harmful.

CONCLUSIONS

Monitoring for adverse effects and the use of techniques to minimize systemic absorption (spacers and mouth rinsing) are recommended when high-dose inhaled glucocorticoid therapy is used. Intranasal and intravenous glucocorticoid products are not recommended for administration via nebulizer because of safety concerns. Until further data are available, inhaled glucocorticoids are thought to be equivalent on a microgram-per-microgram basis rather than an actuation-per-actuation basis. Theophylline is no longer recommended for treatment of acute exacerbations in nonhospitalized patients not already receiving the medication, and the link between deterioration of asthma control (and the risk for death) and regular inhaled beta-adrenergic agonists appears weak.