SGEM#103: Just Breathe – Inhaled Corticosteroids for Asthma Exacerbations

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Date: January 17th, 2015

I hope everyone has been having a great start to 2015. It’t been really, really busy for me as I get more involved with Emergency Medical Abstracts (EMA). Just did my first EMA recording with Dr. Rob Rogers and Dr. Anand Swaminathan.

EMA is available for free for residents as part of their EMRA Membership in the US or CAEP Residents Membership in Canada. You get an amazing medical education product as part of your residency membership.

I think there are five great reasons why EMA is such an outstanding packing:

30 papers a month critically appraised
A deep dive lecture on a specific topic
An interview by Dr. Richard Bukata the man, the myth the legend that started EMA
A 30 minute lecture from the emergency medicine critical care course
Editorial segment with one of the giants of emergency medicine, Dr. Jerome Hoffman.

As I move forward on the SGEM in 2015 let me know what you think. I am always trying to find better ways to cut that knowledge translation window down from over 10 years to less than one year. Let me know how I can do a better job.

Previous suggestions which have really made the SGEM better are:

SGEM HOP – Getting advanced copies of manuscript prior to publication and doing a critical review, interviewing the author, posting the podcast the week of publication and then having the best social media interactions published in a future peer reviewed journal article. Basically the SGEM-HOP is the best of both worlds. Traditional and non-traditional dissemination of medical education. Check out the latest one with Chris Carpenter and Sanjay Arora on texting emergency department patients to improve follow-up. give us your feedback and you too may be published.
SGEM Extras – Taking 10,000 foot looks at bigger issues in emergency medicine. Check out the one with Jeremy Faust from FOAMCast called Everything you know is wrong. It looks at the limitations and weaknesses of the standard peer review process.
SGEM Classics – These are done with Swami and have been a huge hit. There was OPALS, CRASH-2 and of course NINDS. We are currently working on another SGEM Classic so stay tuned.

A recent suggestion was flipping the SGEM. A listener suggesting posting the paper to be critically reviewed in advance. That way people could read the article before the blog and podcast are posted. This would make the written SGEM review and podcast even more educational. So I will be trying to Flip the SGEM by tweeting and posting on Facebook a link to the next article to be put under the skeptical eye of the SGEM.

Case Scenario: 25-year-old smoker is seen in emergency department for acute respiratory distress. He has a diagnosis of asthma and is an occasional user of salbutamol. He has about two asthma exacerbations/year, one previous hospital admission and no intensive care unit admissions. You are preparing to discharge him home and wonder if inhaled steroids would benefit the systemic steroids you are prescribing.

Question: Is there a benefit for inhaled corticosteroids (ICS) use in the Emergency Department in acute asthma presentations?

Asthma Background:

300 million diagnosed worldwide
1 in 250 deaths worldwide is attributed to asthma
27 million people in the USA have at some time received a diagnosis of asthma
2 million emergency department visits/year (USA)
Up to 20% admission & bounce-back in two weeks
Steroid therapy is central to asthma management
There are several potential advantages to inhaled corticosteroid use such as less systemic side effects, direct delivery to the airway, greater efficacy in reducing airway reactivity and oedema

Reference: Edmonds et al. Early use of inhaled corticosteroids in the emergency department treatment of acute asthma (Review). CDSR Dec 2012.

Population: 1,403 patients from 27 randomized and quasi-randomized controlled trials. The population included adults and children (13 paediatric trials and 7 adult). These were patients that presented to the Emergency Department in acute respiratory distress thought to be due to acute asthma exacerbation.
Intervention: Inhaled corticosteroid therapy (ICS) used in multi-modal therapy for acute presentations for asthma exacerbations. ICS was defined as single or multiple-dose ICS early in their ED treatment.
Comparison: Standard treatments for acute asthma exacerbations; beta 2-agonists and systemic corticosteroids
Outcome:
- Primary Outcome: Admission to hospital via the emergency department.
- Secondary Outcomes: Pulmonary function tests (absolute and predicted peak expiratory flow (PEF) and forced expiratory volume in one second (FEV1), adverse effects of ICS and physiological outcomes. The physiological outcomes examined were; clinical scores, heart rate, respiratory rate, arterial oxygen saturation, blood pressure and pH.

Authors’ Conclusion: “This review found that inhaled corticosteroids used alone or in combination with systemic corticosteroids helped to relieve asthma attacks, were well tolerated, and had few side effects. The authors conclude that at this time there is insufficient evidence to support using ICS alone as a replacement for systemic corticosteroid therapy in acute asthma attacks.”

Quality Checklist for Systematic Review:

The diagnostic question is clinically relevant with an established criterion standard. Yes
- Comment: The question is clinically relevant but does not address the concern for patients who systemic steroids are not administered, which could be useful in paediatric populations or when vomiting or post-tussive type symptoms preclude the use of oral corticosteroids at time of presentation.
The search for studies was detailed and exhaustive. Yes
The methodological quality of primary studies were assessed for common forms of diagnostic research bias. Yes
The assessments of studies were reproducible. Yes
The outcomes were clinically relevant. Yes
There was low statistical heterogeneity for the primary outcomes. Yes  
The treatment effect was large enough and precise enough to be clinically significant. Yes

Key Results: Inhaled corticosteroid use in acute asthma in conjunction with systemic corticosteroids resulted in reduced hospital admissions while not increasing adverse effects or demising the other measures of successful asthma treatment in the emergency department.

ICS reduced admissions OR 0.44, 95% CI 0.31-0.62 n=960

Objective parameters of asthma severity also demonstrated improvements with ICS treatment such as; improvements in peak expiratory flow and forced expiratory volume in one second. There were no significant adverse affects noted with ICS treatment (tremor or nausea and vomiting).

SGEM Comments: This was a well done Cochrane Review on the subject of inhaled corticosteroids for the treatment of acute asthma. I am going to talk a little EBM nerdy here just to reinforce what a good systematic reviewers did.

They did an exhaustive search looking for information on this subject. They went thought all the reference lists, contacted the authors asking about unpunished studies, hand searched abstracts from international conferences, contacted scientific advisors of various pharmaceutical companies who manufacture ICS products and personally reached out to other trialists working in the filed of asthma…now that is what I call exhaustive.

They assess for heterogeneity visually and calculated the I2 statistics which can be seen in the included forrest plot.

0% to 40%: might not be important
30% to 60%: may represent moderate heterogeneity
50% to 90%: may represent substantial heterogeneity
75% to 100%: considerable heterogeneity

They also looked for publication bias using a funnel plot. This helps you visualize the various studies to see if there is any asymmetry. Some EBM people feel that visual inspection of funnel plots is not useful due to the subjective nature of the assessment.

The NNT to prevent one hospital admission was 8 for ICS in acute asthma. Future studies should focus on isolated use of ICS for asthma exacerbations to avoid the use of systemic corticosteroids (oral or intravenous) both in the emergency department and at time of discharge.

Comment on Authors’ Conclusion Compared to SGEM Conclusion: The main outcomes of focus was hospitalization. This is a very important patient oriented outcome and emergency physician oriented outcome; especially with all the current emergency department over-crowding issues as admitted patients are being boarded in the department.
The secondary outcomes were parameters of asthma severity such as peak flow and forced expiratory peak flow in one second. These often predict hospitalization in the emergency department but in isolation are not as useful to the emergency provider. This because these assessments of peak flow and FEV1 are often not used across all emergency departments.

SGEM Bottom Line: Adding some form of inhaled corticosteroid to acute asthma presentations (either low or high dose) is likely to benefit your patient (adult or paediatric) on multiple levels, but mainly admission requirements. The use of inhaled corticosteroids will not circumvent the requirement for systemic corticosteroid use.

Case Resolution: The 25 year-old man with an asthma exacerbation is discharged home with a short course of oral steroids and inhaled corticosteroids. He is also encouraged to quit smoking cigarettes.

Clinical Application: Inhaled corticosteroid is an option to be considered for acute asthma presentations in children and adults in the emergency department but only when used in conjunction with systemic corticosteroids.

What Do I Tell My Patient? Early use of steroid puffers with with oral steroids will improve your chances of not needing to be admitted to hospital with your asthma flair.

Keener Kontest: Last weeks winner was Andrew Buelt. He knew the first text message was send December 3rd, 1992 with the message ”Merry Christmas”.

Listen to this weeks episode of the SGEM for the Keener Kontest. If you know the answer then send it to TheSGEM@gmail.com with keener kontest in the subject line. Be the first one with the correct answer and I will send you a cool SGEM skeptical prize.