Cochrane Review: Nebulized epinephrine for croup in children

Abstract

BackgroundCroup is a common childhood illness characterized by barky cough, stridor, hoarseness and respiratory distress. Children with severe croup are at risk for intubation. Nebulized epinephrine (NE) may prevent intubation.ObjectivesTo evaluate the efficacy and safety of NE in children presenting to emergency department (ED) or admitted to hospital with croup.Search methodsWe searched CENTRAL (The Cochrane Library 2010, Issue 4), containing the Cochrane Acute Respiratory Infections Group's Specialized Register, MEDLINE (1966 to November Week 1, 2010), EMBASE (1980 to November 2010), Web of Science (1974 to November 2010), CINAHL (1982 to November 2010) and Scopus (1996 to November 2010).Selection criteriaRandomized controlled trials (RCTs) or quasi‐RCTs of children with croup evaluated in an ED or admitted to hospital. Comparisons were: NE versus placebo, racemic NE versus L‐epinephrine (an isomer), and NE delivered by intermittent positive pressure breathing (IPPB) versus NE without IPPB. Primary outcome was change in croup score post‐treatment. Secondary outcomes were rate and duration of intubation and hospitalization, croup return visit, parental anxiety and side effects.Data collection and analysisTwo authors independently identified potentially relevant studies by title and abstract (when available) and examined relevant studies using a priori inclusion criteria, followed by methodologic quality assessment. One author extracted data while the second checked accuracy. We performed standard statistical analyses.Main resultsEight studies (225 participants) were included. NE was associated with croup score improvement 30 minutes post‐treatment (three RCTs, standardized mean difference (SMD) ‐0.94; 95% confidence interval (CI) ‐1.37 to ‐0.51; I2 statistic = 0%). This effect was not significant two and six hours post‐treatment. NE was associated with significantly shorter hospital stay than placebo (one RCT, mean difference ‐32.0 hours; 95% CI ‐59.1 to ‐4.9). Comparing racemic and L‐epinephrine, no difference in croup score was found after 30 minutes (SMD 0.33; 95% CI ‐0.42 to 1.08). After two hours, L‐epinephrine showed significant reduction compared with racemic epinephrine (one RCT, SMD 0.87; 95% CI 0.09 to 1.65). There was no significant difference in croup score between administration of NE via IPPB versus nebulization alone at 30 minutes (one RCT, SMD ‐0.14; 95% CI ‐1.24 to 0.95) or two hours (SMD ‐0.72; 95% CI ‐1.86 to 0.42).Authors' conclusionsNE is associated with clinically and statistically significant transient reduction of symptoms of croup 30 minutes post‐treatment. Evidence does not favor racemic epinephrine or LE, or IPPB over simple nebulization.Plain Language SummaryNebulized epinephrine for croup in childrenCroup is a common childhood illness that is usually caused by a viral infection. Symptoms of croup include a hoarse voice, a 'barking' cough and noisy breathing. These symptoms are the result of swelling that occurs in the area of the windpipe (trachea) just below the voice box (larynx). Although most cases of croup are mild and resolve on their own, occasionally the swelling can be severe enough to cause difficulty in breathing. In these children, epinephrine (also called adrenaline) is a medication that is inhaled as a mist to temporarily shrink the swollen area in the trachea.This review looked at trials of inhaled epinephrine for the treatment of children with croup. Compared to no medication, inhaled epinephrine improved croup symptoms in children at 30 minutes following treatment (three studies, 94 children). This treatment effect disappeared two hours after treatment (one study, 20 children). However, children's symptoms did not become worse than prior to treatment. No study measured adverse events. This review is comprised of only eight studies and the number of included children was small (225). Few studies examined similar outcomes, therefore data could often not be pooled and conclusions are based on one or few studies.

A Systematic Review and Comprehensive Critical Analysis Examining the Use of Prednisolone for the Treatment of Mild to Moderate Croup

“…The Geelhoed score has demonstrated inter-rater reliability, with a weighted kappa of above 0.85 in two independent studies, indicating reasonable inter-observer agreement [ 83 ]. The Taussig score, which was used by Fifoot and Ting [ 53 ], does not appear to have been tested for validity and reliability with children experiencing croup [ 84 ] whilst the TOP score is a brief telephone outpatient scoring system that assess the presence of stridor and barky cough by asking parents about the child’s symptoms in the last 24 hours and has undergone limited testing for validity and reliability [ 85 ]. Croup scores themselves at entry point to trials are subject to both inter- and intra-observer variation because not all the nurses scoring the children are the same or it may be unlikely that the same nurse scores the same child later, meaning that the formal establishment of inter-rater reliability is important, particularly if it has not been demonstrated.…”

Paramedic assessment and treatment of upper airway obstruction in pediatric patients: an exploratory analysis by the Children's Safety Initiative-Emergency Medical Services

“…Nebulized epinephrine, via its alpha-1 effect of vasoconstriction, is a highly effective treatment for upper airway obstruction caused by croup. 1–5 Asthma causes lower airway obstruction and is treated with albuterol whose beta-2 mechanism causes relaxation of the lower airways. 6 Albuterol does not have significant alpha-1 effect making it ineffective for croup, In addition, its’ beta effect could potentially cause vasodilation, and theoretically worsen upper airway edema.…”