Asthma is the most common chronic disease in children, and acute exacerbations of asthma are one of the most common reasons for children to seek emergency care and require urgent hospitalization. Approximately half to two-thirds of children with asthma who seek emergency care can be classified as having mild respiratory distress, and between 2 and 5% have severe respiratory distress; the remainder has moderate respiratory distress.



Summaries of systematic reviews

Cochrane Summary: Holding chambers (spacers) versus nebulisers for delivery of beta-agonist relievers in the treatment of an asthma attack (2013)


Cates, CJ, Welsh, EJ, Rowe, BH,

Review question: When someone is having an asthma attack is it as safe and effective to use a spacer instead of a nebuliser? Background: During an asthma attack, the airways (tubes in the lungs) narrow making breathing difficult. The initial response to an asthma attack is to treat with a drug that can open up the airways and make breathing easier. These drugs are called bronchodilators and in this review we are looking specifically at a class of bronchodilators called beta-agonists (for example salbutamol). These drugs can be taken straight from an inhaler, but during an asthma attack they are easier to take using either a spacer or a nebuliser. A spacer is a hollow chamber. A puff of drug from an inhaler is added to the chamber and then the person breathes in and out normally (also described as tidal breathing), from a mouthpiece on the chamber. A nebuliser is a machine with a mask that goes over the person's mouth and nose and through which a constant stream of drug and air (or oxygen) is breathed in and out normally. What evidence did we find? We found 39 clinical trials involving 1897 children and 729 adults. Thirty-three of the trials were conducted in an emergency room (or emergency department) and community settings (such as a GP's surgery), and six trials were on inpatients (people in hospital) with acute asthma (207 children and 28 adults). Overall we judged the quality of the evidence to be moderate. What do the studies tell us? Taking beta-agonists through either a spacer or a nebuliser in the emergency department did not make a difference to the number of adults being admitted to hospital, whilst in children we can be fairly confident that nebulisers are not better than spacers at preventing admissions. In children, the length of stay in the emergency department was significantly shorter when the spacer was used instead of a nebuliser. The average stay in the emergency department for children given nebulised treatment was 103 minutes. Children given treatment via spacers spent an average of 33 minutes less. In adults, the length of stay in the emergency department was similar for the two delivery methods. However the adult studies were conducted slightly differently which may have made it more difficult to show a difference in the length of stay in the emergency department. Because all the adult studies used a so-called "double-dummy" design, the adults received a spacer AND a nebuliser (either beta-agonist in a spacer and a dummy nebuliser or vice versa) which meant both groups of people were in the emergency department for as long as it took to take both treatments. Lung function tests were also similar for the two delivery methods in both adults and children. Pulse rate was lower in children taking beta-agonists through a spacer (mean difference 5% baseline), and there was a lower risk of developing tremor. Conclusion: Metered-dose inhalers with a spacer can perform at least as well as wet nebulisation in delivering beta-agonists in children with acute asthma, but we are less certain about the results in adults.

Cochrane Summary: Combined inhaled anticholinergics and beta2-agonists for initial treatment of acute asthma in children (2013)


Griffiths, B, Ducharme, FM,

Background: In an asthma attack, the airways (small tubes in the lungs) narrow because of inflammation (swelling), muscle spasms and mucus secretions. Other symptoms include wheezing, coughing and chest tightness. This makes breathing difficult. Reliever inhalers typically contain short-acting beta2-agonists (SABAs) that relax the muscles in the airways, opening the airways so that breathing is easier. Anticholinergic drugs work by opening the airways and decreasing mucus secretions. Review question: We looked at randomised controlled trials to find out whether giving inhaled anticholinergics plus SABAs (instead of SABAs on their own) in the emergency department provides benefits or harms in children having an asthma attack. Key results: We found that children with a moderate or severe asthma attack who were given both drugs in the emergency department were less likely to be admitted to the hospital than those who only had SABAs. In the group receiving only SABAs, on average 23 out of 100 children with acute asthma were admitted to hospital compared with an average of 17 (95% CI 15 to 20) out of 100 children treated with SABAs plus anticholinergics. Taking both drugs was also better at improving lung function. Taking both drugs did not seem to reduce the possibility of another asthma attack. Fewer children treated with anticholinergics reported nausea and tremor, but no significant group difference was observed for vomiting. Quality of the evidence and further research: Most of the studies were in preschool- and school-aged children; three studies also included a small proportion of infants under 18 months of age, although there was no evidence that inclusion of these infants with wheezy episodes affected the results. Nine trials (45%) were at a low risk of bias and we regarded the evidence for hospitalisation as high quality. Physicians can administer the dose of anticholinergic and SABA in several different ways; as a single dose, or as a certain number of doses or more flexibly. Most of the trials gave the children two or three doses and we think that more research is needed to improve characterization of children that benefit from, and the most effective number and frequency of doses of, anticholinergic treatment.

Cochrane Summary: Inhaled corticosteroids for acute asthma following emergency department discharge (2012)


Edmonds, ML, Milan, SJ, Brenner, BE, Camargo, CA, Rowe, BH,

Acuteasthma is a common cause of visits toemergencydepartments (ED) and the majority of patients are treated and discharged home. Some people will have arelapseofacuteasthma within two weeks of being discharged after apparently successful treatment. Beta2-agonist drugs are used to open the muscles in the airways and corticosteroids drugs are used to reduce inflammation of the swollen airways.Corticosteroidscan be inhaled (ICS) or swallowed as a tablet (so-calledoralcorticosteroids). ICS may reduceadverse effectsand get to the airways more directly thanoralcorticosteroids. Thisreviewof trials found that there was insufficient evidence that inhaling corticosteroids as well as taking the drugs orally is better thanoraluse alone, afteremergencydepartment treatment for an asthma attack. There is also insufficient evidence that taking ICS alone is as good as taking them orally, although there is some evidence to support using ICS alone for mild asthma attacks afteremergencydepartment discharge. Moreresearchis needed.

Cochrane Summary: Role of ketamine for management of acute severe asthma in children (2012)


Jat, KR, Chawla, D,

Children frequently visit theemergencydepartment foracuteexacerbation of asthma. Some of these children fail to respond tostandard treatment(corticosteroids and bronchodilators) with increasedmorbidity. Ketamine has bronchodilatory properties and may be useful foracuteexacerbation of asthma. We evaluated theefficacyof ketamine for management of severeacuteasthma in children who had not responded to standardtherapy. We found, through systematic search, only onestudywhere investigators assessed the usefulness of ketamine for management of severeacuteasthma in children. While this singlestudysuggested that there is a lack of evidence for usefulness of ketamine inacuteexacerbation of asthma in children, more trials are needed regarding the use of ketamine inacuteasthma before more specific recommendations can be made.

Cochrane Summary: What are the effects of educational interventions delivered to children and/or their families, who have experienced an emergency department visit with their asthma within the previous 12 months? (2010)


Boyd, M, Lasserson, TJ, McKean, MC, Gibson, PG, Ducharme, FM, Haby, M,

Asthma care for children in our society is common and costly. There is now evidence that educationalinterventionfor children who have attended theemergencydepartment for asthma lowers theriskof the need for futureemergencydepartment visits and hospital admissions. Thisreviewlooked at studies which compared usual care for asthma to more intensive educational programmes and the results showed astatistically significantreduction in the treatment groups needing subsequentemergencydepartment visits or hospital admissions. We were not able to determine the most effective type, duration or intensity ofeducationthat should be offered to children to offer the best asthma outcomes.

Cochrane Summary: Magnesium sulfate for treating exacerbations of acute asthma in the emergency department (2009)


Rowe, BH, Bretzlaff, J, Bourdon, C, Bota, G, Blitz, S, Camargo, CA,

In an asthma attack, the airways (passages to the lungs) narrow from muscle spasms and swelling (inflammation). Bronchodilator drugs (reliever inhalers) can be used to relax the muscles and open the airways, and corticosteroid drugs to reduce the inflammation. Magnesium sulfate is a drug that can also affect muscles, and may reduce inflammation as well. It can be given through a drip in the veins (intravenously). Thereviewof trials found thatintravenousmagnesium sulfate in addition to bronchodilators seems to be safe and beneficial for people with severe asthma attacks, or those for whom bronchodilators are not working.

Cochrane Summary: Early emergency department treatment of acute asthma with systemic corticosteroids (2008)


Rowe, BH, Spooner, C, Ducharme, F, Bretzlaff, J, Bota, G,

In an asthma attack, the airways (passages to the lungs) narrow from muscle spasms and swelling (inflammation). Bronchodilators (reliever inhalers to open up the lungs and airways) can be used for the spasms, and corticosteroids for the swelling.Corticosteroidscan be inhaled, or taken by mouth (orally) or through a drip into the veins (intravenously). Thereviewof trials found thatsystemic(oralorintravenous) corticosteroids reduce the need for people with asthma attacks to stay in hospital, with fewadverse effects.