Clinical Progress Note: Care of Children Hospitalized for Acute Asthma Exacerbation

The 2007 NHLBI guidelines are clear that short-acting beta-2 agonists (SABA), delivered via nebulization or metered-dose inhaler (MDI) with a valved holding chamber (VHC), along with systemic steroids, should be the primary treatment in pediatric acute asthma exacerbations.¹ The guidelines caution that nebulization therapy might be needed for patients who are ineffective in using MDIs because of age, level of agitation, or severity of asthma symptoms. Specific recommendations for management in the inpatient setting are brief but note that inpatient medication administration and care should mirror ED management strategies.¹ Specific in-hospital management recommendations regarding nebulization vs MDI are not addressed.

A Cochrane Review by Cates et al. assessed pediatric and adult randomized trials comparing SABA delivery via MDI-VHC with that via nebulization.⁶ The analysis included 39 trials with a total of 729 adults and 1,897 children. Six of the included trials were conducted in an inpatient setting (207 enrolled children in these studies). The authors found that mechanism of SABA delivery did not affect ED admission rates or significantly influence other markers of treatment response (peak flow and forced expiratory volumes). In children, MDI-VHC use was associated with shorter ED length of stay, as well as a decreased frequency of common SABA side effects (ie, tachycardia and tremor). This review cites several areas in which research is needed, including MDI use in severe asthma exacerbations. This population often falls outside pediatric hospitalists’ scope of practice because these patients often require ICU-level care.

A recent systematic review of pediatric acute asthma management strategies by Castro-Rodriguez et al. found that using MDI-VHC to deliver SABA was superior to using nebulization as measured by decreased ED admission rates and ED length of stay, improved asthma clinical scores, and reduced SABA side effects.⁷ A 2016 prospective randomized trial of MDI-VHC vs nebulization in preschool-aged children presenting to an ED with asthma or virally mediated wheeze found that the SABA delivered via MDI-VHC was at least as effective as that delivered via nebulization.⁸

International asthma management guidelines more strongly recommend MDI-only treatment for pediatric patients admitted with moderate asthma.⁹ Despite this guidance, and the literature supporting transition in inpatient settings to bronchodilator administration via MDI, there are several barriers to exclusive MDI use in the inpatient setting. As mentioned by Cates et al., a recognized challenge in MDI-VHC adoption is overcoming the “nebulizer culture” in treating pediatric acute asthma symptoms.⁶ Perhaps not surprisingly, Press et al., in a retrospective secondary analysis of 25 institutions managing adults and children with acute asthma symptoms, found that 32% of all pediatric patients assessed received only nebulized SABA treatments during their hospitalization.¹⁰ Transitioning from nebulized albuterol to exclusively MDI-VHC albuterol will require significant systems changes.

Clinical pathways operationalize practice guidelines and provide guidance on the treatments, testing, and management of an illness. Use of pediatric asthma pathways has increased steadily in the past decade, with one study of over 300 hospitals finding that, between 2005 to 2015, pathway implementation increased from 27% to 86%.¹¹ This expanded use has coincided with a proliferation of publications evaluating the effects of these pathways. A systematic review examining the implementation and impact of asthma protocols identified over 100 articles published between 1986 and 2010, with the majority published after 2005.¹² The study found implementation of guidelines through an asthma pathway generally improved patient care and provider performance regardless of implementation method.