Admissions to Canadian hospitals for acute asthma: a prospective, multicentre study

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Effective Asthma Management: Is It Time to Let the AIR out of SABA?

For years, standard asthma treatment has included short acting beta agonists (SABA), including as monotherapy in patients with mild asthma symptoms. In the Global Initiative for Asthma 2019 strategy for the management of asthma, the authors recommended a significant departure from the traditional treatments. Short acting beta agonists (SABAs) are no longer recommended as the preferred reliever for patients when they are symptomatic and should not be used at all as monotherapy because of significant safety concerns and poor outcomes. Instead, the more appropriate course is the use of a combined inhaled corticosteroid–fast acting beta agonist as a reliever. This paper discusses the issues associated with the use of SABA, the reasons that patients over-use SABA, difficulties that can be expected in overcoming SABA over-reliance in patients, and our evolving understanding of the use of “anti-inflammatory relievers” in our patients with asthma.

Management of severe asthma exacerbation: guidelines from the Société Française de Médecine d'Urgence, the Société de Réanimation de Langue Française and the French Group for Pediatric Intensive Care and Emergencies

BACKGROUND

The French Emergency Medicine Society, the French Intensive Care Society and the Pediatric Intensive Care and Emergency Medicine French-Speaking Group edited guidelines on severe asthma exacerbation (SAE) in adult and pediatric patients.

RESULTS

The guidelines were related to 5 areas: diagnosis, pharmacological treatment, oxygen therapy and ventilation, patients triage, specific considerations regarding pregnant women. The literature analysis and formulation of the guidelines were conducted according to the Grade of Recommendation Assessment, Development and Evaluation methodology. An extensive literature research was conducted based on publications indexed in PubMed™ and Cochrane™ databases. Of the 21 formalized guidelines, 4 had a high level of evidence (GRADE 1+/-) and 7 a low level of evidence (GRADE 2+/-). The GRADE method was inapplicable to 10 guidelines, which resulted in expert opinions. A strong agreement was reached for all guidelines.

CONCLUSION

The conjunct work of 36 experts from 3 scientific societies resulted in 21 formalized recommendations to help improving the emergency and intensive care management of adult and pediatric patients with SAE.

Engaging patients and primary care providers in the design of novel opinion leader based interventions for acute asthma in the emergency department: a mixed methods study

BACKGROUND

Multifaceted interventions driven by the needs of patients and providers can help move evidence into practice more rapidly. This study engaged both patients and primary care providers (PCPs) to help design novel opinion leader (OL)-based interventions for patients with acute asthma seen in emergency departments (EDs).

METHODS

A mixed methods design was employed. In phase I, we invited convenience samples of patients with asthma presenting to the ED and PCPs to participate in a survey. Perceptions with respect to: a) an ideal OL-profile for asthma guidance; and b) content, style and delivery methods of OL-based interventions in acute asthma directed from the ED were collected. In phase II, we conducted focus groups to further explore preferences and expectations for such interventions with attention to barriers and facilitators for implementation.

RESULTS

Overall, 54 patients completed the survey; 39% preferred receiving guidance from a respirologist, 44% during their ED visit and 56% through individual discussions. In addition, 55% expressed interest in having PCP follow-up within a week of ED discharge. A respirologist was identified as the ideal OL-profile by 59% of the 39 responding PCPs. All expressed interest in receiving notification of their patients' ED presentation, most within a week and including diagnosis and ED/post ED-treatment. Personalized, guideline-based, recommendations were considered to be the ideal content by the majority; 39% requested this guidance through a pamphlet faxed to their offices. In the focus groups, patients and PCPs recognized the importance of health professional liaisons in transitions in care; patient anxiety and PCP time constraints were identified as potential barriers for ED-educational information uptake and proper post-ED follow-up, respectively.

CONCLUSIONS

Engaging patients and PCPs yielded actionable information to tailor OL-based multifaceted interventions for acute asthma in the ED. We identified potential facilitators for the implementation of such interventions (e.g., patient interaction with alternative health care professionals who could facilitate transitions in asthma care between the ED and the primary care setting), and for the provision of post discharge self-management education (e.g., consideration of the first week of ED discharge as a practical time frame for this intervention). Prioritization of identified barriers (e.g., lack of PCP involvement) could be addressed by the identification of potential early adopters in practice environments (e.g., clinicians with special interest in asthma).

Combined inhaled beta-agonist and anticholinergic agents for emergency management in adults with asthma

BACKGROUND

Inhaled short-acting anticholinergics (SAAC) and short-acting beta₂-agonists (SABA) are effective therapies for adult patients with acute asthma who present to the emergency department (ED). It is unclear, however, whether the combination of SAAC and SABA treatment is more effective in reducing hospitalisations compared to treatment with SABA alone.

OBJECTIVES

To conduct an up-to-date systematic search and meta-analysis on the effectiveness of combined inhaled therapy (SAAC + SABA agents) vs. SABA alone to reduce hospitalisations in adult patients presenting to the ED with an exacerbation of asthma.

SEARCH METHODS

We searched MEDLINE, Embase, CINAHL, SCOPUS, LILACS, ProQuest Dissertations & Theses Global and evidence-based medicine (EBM) databases using controlled vocabulary, natural language terms, and a variety of specific and general terms for inhaled SAAC and SABA drugs. The search spanned from 1946 to July 2015. The Cochrane Airways Group provided search results from the Cochrane Airways Group Register of Trials which was most recently conducted in July 2016. An extensive search of the grey literature was completed to identify any other potentially relevant studies.

SELECTION CRITERIA

Included studies were randomised or controlled clinical trials comparing the effectiveness of combined inhaled therapy (SAAC and SABA) to SABA treatment alone to prevent hospitalisations in adults with acute asthma in the emergency department. Two independent review authors assessed studies for inclusion using pre-determined criteria.

DATA COLLECTION AND ANALYSIS

For dichotomous outcomes, we calculated individual and pooled statistics as risk ratios (RR) or odds ratios (OR) with 95% confidence intervals (CI) using a random-effects model and reporting heterogeneity (I²). For continuous outcomes, we reported individual trial results using mean differences (MD) and pooled results as weighted mean differences (WMD) or standardised mean differences (SMD) with 95% CIs using a random-effects model.

MAIN RESULTS

We included 23 studies that involved a total of 2724 enrolled participants. Most studies were rated at unclear or high risk of bias.Overall, participants receiving combination inhaled therapy were less likely to be hospitalised (RR 0.72, 95% CI 0.59 to 0.87; participants = 2120; studies = 16; I² = 12%; moderate quality of evidence). An estimated 65 fewer patients per 1000 would require hospitalisation after receiving combination therapy (95% 30 to 95), compared to 231 per 1000 patients receiving SABA alone. Although combination inhaled therapy was more effective than SABA treatment alone in reducing hospitalisation in participants with severe asthma exacerbations, this was not found for participants with mild or moderate exacerbations (test for difference between subgroups P = 0.02).Participants receiving combination therapy were more likely to experience improved forced expiratory volume in one second (FEV₁) (MD 0.25 L, 95% CI 0.02 to 0.48; participants = 687; studies = 6; I² = 70%; low quality of evidence), peak expiratory flow (PEF) (MD 36.58 L/min, 95% CI 23.07 to 50.09; participants = 1056; studies = 12; I² = 25%; very low quality of evidence), increased percent change in PEF from baseline (MD 24.88, 95% CI 14.83 to 34.93; participants = 551; studies = 7; I² = 23%; moderate quality of evidence), and were less likely to return to the ED for additional care (RR 0.80, 95% CI 0.66 to 0.98; participants = 1180; studies = 5; I² = 0%; moderate quality of evidence) than participants receiving SABA alone.Participants receiving combination inhaled therapy were more likely to experience adverse events than those treated with SABA agents alone (OR 2.03, 95% CI 1.28 to 3.20; participants = 1392; studies = 11; I² = 14%; moderate quality of evidence). Among patients receiving combination therapy, 103 per 1000 were likely to report adverse events (95% 31 to 195 more) compared to 131 per 1000 patients receiving SABA alone.

AUTHORS' CONCLUSIONS

Overall, combination inhaled therapy with SAAC and SABA reduced hospitalisation and improved pulmonary function in adults presenting to the ED with acute asthma. In particular, combination inhaled therapy was more effective in preventing hospitalisation in adults with severe asthma exacerbations who are at increased risk of hospitalisation, compared to those with mild-moderate exacerbations, who were at a lower risk to be hospitalised. A single dose of combination therapy and multiple doses both showed reductions in the risk of hospitalisation among adults with acute asthma. However, adults receiving combination therapy were more likely to experience adverse events, such as tremor, agitation, and palpitations, compared to patients receiving SABA alone.

Increased health service use for asthma, but decreased for COPD: Northumbrian hospital episodes, 2013-2014

The burden of respiratory disease has persisted over the years, for both men and women. The aim of the present study was to investigate the hospital episode rates in respiratory disease and to understand whether and how the use of the health service for respiratory disease might have changed in recent years in the North-East of England. Hospital episode data covering two full calendar years (in 2013–2014) was extracted from the Northumbria Healthcare NHS Foundation Trust, which serves a population of nearly half a million. Hospital episode rates were calculated from admissions divided by annual and small area-specific population size by sex and across age groups, presented with per 100,000 person-years. The use of the health service for influenza and pneumonia, acute lower respiratory infections and chronic obstructive pulmonary disease (COPD) increased with an advancing age, except for acute upper respiratory infections and asthma. Overall, the use of the health service for common respiratory diseases has seemed to be unchanged, except for asthma. There were large increases in young adults aged 20–50 for both men and women and the very old aged 90+ in women. Of note, there were large increases in acute lower respiratory infections for both men and women aged 90+, whereas there was also a large decrease in COPD in women aged 80–90. This is the first study to examine health service use for respiratory diseases by calculating the detailed population size as denominator. Re-diverting funding to improve population health on a yearly basis may serve the changing need in local areas.

Effectiveness of Educational Interventions to Increase Primary Care Follow-up for Adults Seen in the Emergency Department for Acute Asthma: A Systematic Review and Meta-analysis

OBJECTIVES

Patients with asthma commonly present to emergency departments (ED) with exacerbations. Asthma guidelines recommend close follow-up with a primary care provider (PCP) after ED discharge; however, this linkage is often delayed or absent. The objective of this study was to assess whether ED-directed educational interventions improve office follow-up with PCPs after ED discharge for acute asthma.

METHODS

Comprehensive literature searches were conducted in seven electronic databases (1946 to 2014). Randomized controlled clinical trials examining the effectiveness of educational interventions to increase office follow-up with a PCP were included. Study quality was determined using the Cochrane risk of bias tool; fidelity of the interventions was assessed using the Treatment Fidelity Assessment Grid. Using study data, risk ratios (RRs),and the number needed to treat for benefit (NNTB) with 95% confidence intervals (CI) were calculated using random-effects models.

RESULTS

From 427 potentially relevant studies, five (n = 825) were included. The overall risk of bias was unclear, and the description of intervention fidelity varied across the studies. Educational interventions targeting either patients or PCPs led to a greater likelihood of having primary care follow-up after ED discharge (RR = 1.6; 95% CI = 1.31 to 1.87; I(2)  = 0%). The number needed to treat for benefit was six (95% CI = 4 to 11). No significant benefit was observed in reductions of relapses (RR = 1.3; 95% CI = 0.82 to 1.98; I(2)  = 23%) and admissions (RR = 0.51; 95% CI = 0.24 to 1.06; I(2)  = 0%). Due to the small number of studies for each comparison, publication bias was not formally assessed.

CONCLUSIONS

ED-directed educational interventions targeting either patients or providers increase the chance of having office follow-up visits with PCPs after asthma exacerbations. Their impact on health-related outcomes (e.g., relapse and admissions) remains unclear.

Clinical, economic, and humanistic burden of asthma in Canada: a systematic review

BACKGROUND

Asthma, one of the most common chronic respiratory diseases, affects about 3 million Canadians. The objective of this study is to provide a comprehensive evaluation of the published literature that reports on the clinical, economic, and humanistic burden of asthma in Canada.

METHODS

A search of the PubMed, EMBASE, and EMCare databases was conducted to identify original research published between 2000 and 2011 on the burden of asthma in Canada. Controlled vocabulary with "asthma" as the main search concept was used. Searches were limited to articles written in English, involving human subjects and restricted to Canada. Articles were selected for inclusion based on predefined criteria like appropriate study design, disease state, and outcome measures. Key data elements, including year and type of research, number of study subjects, characteristics of study population, outcomes evaluated, results, and overall conclusions of the study, were abstracted and tabulated.

RESULTS

Thirty-three of the 570 articles identified by the clinical and economic burden literature searches and 14 of the 309 articles identified by the humanistic burden literature searches met the requirements for inclusion in this review. The included studies highlighted the significant clinical burden of asthma and show high rates of healthcare resource utilization among asthma patients (hospitalizations, ED, physician visits, and prescription medication use). The economic burden is also high, with direct costs ranging from an average annual cost of $366 to $647 per patient and a total annual population-level cost ranging from ~ $46 million in British Columbia to ~ $141 million in Ontario. Indirect costs due to time loss from work, productivity loss, and functional impairment increase the overall burden. Although there is limited research on the humanistic burden of asthma, studies show a high (31%-50%) prevalence of psychological distress and diminished QoL among asthma patients relative to subjects without asthma.

CONCLUSIONS

As new therapies for asthma become available, economic evaluations and assessment of clinical and humanistic burden will become increasingly important. This report provides a comprehensive resource for health technology assessment that will assist decision making on asthma treatment selection and management guidelines in Canada.

Inhaled steroids for acute asthma following emergency department discharge

BACKGROUND

Patients with acute asthma treated in the emergency department (ED) are frequently treated with inhaled beta(2)-agonists and systemic corticosteroids after discharge. The use of inhaled corticosteroids (ICS) following discharge may also be beneficial in improving patient outcomes after acute asthma.

OBJECTIVES

To determine the effectiveness of ICS on outcomes in the treatment of acute asthma following discharge from the ED. To quantify the effectiveness of ICS therapy on acute asthma following ED discharge, when used in addition to, or as a substitute for, systemic corticosteroids.

SEARCH METHODS

Controlled clinical trials (CCTs) were identified from the Cochrane Airways Review Group register, which consists of systematic searches of EMBASE, MEDLINE and CINAHL databases supplemented by handsearching of respiratory journals and conference proceedings. In addition, primary authors and pharmaceutical companies were contacted to identify eligible studies. Bibliographies from included studies, known reviews and texts also were searched. The searches have been conducted up to September 2012

SELECTION CRITERIA

We included both randomised controlled trials (RCTs) and quasi-RCTs. Studies were included if patients were treated for acute asthma in the ED or its equivalent, and following ED discharge were treated with ICS therapy either in addition to, or as a substitute for, oral corticosteroids. Two review authors independently assessed articles for potential relevance, final inclusion and methodological quality.

DATA COLLECTION AND ANALYSIS

Data were extracted independently by two review authors, or confirmed by the study authors. Several authors and pharmaceutical companies provided unpublished data. The data were analysed using the Cochrane Review Manager software. Where appropriate, individual and pooled dichotomous outcomes were reported as odds ratios (OR) or relative risks (RR) with 95% confidence intervals (CIs). Where appropriate, individual and pooled continuous outcomes were reported as mean differences (MD) or standardized mean differences (SMD) with 95% CIs. The primary analysis employed a fixed effect model and heterogeneity is reported using I-squared (I(2)) statistics.

MAIN RESULTS

Twelve trials were eligible for inclusion. Three of these trials, involving a total of 909 patients, compared ICS plus systemic corticosteroids versus oral corticosteroid therapy alone. There was no demonstrated benefit of ICS therapy when used in addition to oral corticosteroid therapy in the trials. Relapses were reduced; however, this was not statistically significant with the addition of ICS therapy (OR 0.68; 95% CI 0.46 to 1.02; 3 studies; N = 909). In addition, no statistically significant differences were demonstrated between the two groups for relapses requiring admission, quality of life, symptom scores or adverse effects.Nine trials, involving a total of 1296 patients compared high-dose ICS therapy alone versus oral corticosteroid therapy alone after ED discharge. There were no significant differences demonstrated between ICS therapy alone versus oral corticosteroid therapy alone for relapse rates (OR 1.00; 95% CI 0.66 to 1.52; 4 studies; N = 684), admissions to hospital, or in the secondary outcomes of beta(2)-agonist use, symptoms or adverse events. However, the sample size was not adequate to exclude the possibility of either treatment being significantly inferior and people with severe asthma were excluded from these trials.

AUTHORS' CONCLUSIONS

There is insufficient evidence that ICS therapy provides additional benefit when used in combination with standard systemic corticosteroid therapy upon ED discharge for acute asthma. There is some evidence that high-dose ICS therapy alone may be as effective as oral corticosteroid therapy when used in mild asthmatics upon ED discharge; however, the confidence intervals were too wide to be confident of equal effectiveness. Further research is needed to clarify whether ICS therapy should be employed in acute asthma treatment following ED discharge. The review does not suggest any reason to stop usual treatment with ICS following ED discharge, even if a course of oral corticosteroids are prescribed.

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

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

BACKGROUND

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

OBJECTIVES

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

SEARCH METHODS

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

SELECTION CRITERIA

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

DATA COLLECTION AND ANALYSIS

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

MAIN RESULTS

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

AUTHORS' CONCLUSIONS

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

Take my breath away: a case of lactic acidosis in an asthma exacerbation

A 36-year-old male with a history of chronic asthma presented to an emergency department with shortness of breath consistent with an asthma exacerbation. He had persistent tachypnea following inhaled bronchodilator treatment; thus, the workup and differential diagnosis were expanded. He was found to have a mixed respiratory alkalosis and metabolic acidosis with elevated serum lactate without an obvious cause and was admitted to hospital. His case was reviewed, and the lactic acidosis was thought to be caused by inhaled β2-agonist use. Emergency physicians should be aware of the potential side effects of inhaled β2-agonists as lactic acidosis may complicate clinical assessment and management of asthma exacerbations and lead to unnecessary and potentially dangerous escalations in therapy.

Asthma length of stay in hospitals in London 2001-2006: demographic, diagnostic and temporal factors

Asthma is a condition of significant public health concern associated with morbidity, mortality and healthcare utilisation. This study identifies key determinants of length of stay (LOS) associated with asthma-related hospital admissions in London, and further explores their effects on individuals. Subjects were primarily diagnosed and admitted for asthma in London between 1^st January 2001 and 31^st December 2006. All repeated admissions were treated uniquely as independent cases. Negative binomial regression was used to model the effect(s) of demographic, temporal and diagnostic factors on the LOS, taking into account the cluster effect of each patient's hospital attendance in London. The median and mean asthma LOS over the period of study were 2 and 3 days respectively. Admissions increased over the years from 8,308 (2001) to 10,554 (2006), but LOS consistently declined within the same period. Younger individuals were more likely to be admitted than the elderly, but the latter significantly had higher LOS (p<0.001). Respiratory related secondary diagnoses, age, and gender of the patient as well as day of the week and year of admission were important predictors of LOS. Asthma LOS can be predicted by socio-demographic factors, temporal and clinical factors using count models on hospital admission data. The procedure can be a useful tool for planning and resource allocation in health service provision.