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A multicenter, randomized, double-blind, controlled trial of nebulized epinephrine in infants with acute
Claire Wainwright1, Luis Altamirano, Marise Cheney
1Department of Respiratory Medicine, Royal Children's Hospital, Brisbane, Queensland, Australia. claire_wainwright@health.qld.gov.au
Insights
Nebulized epinephrine did not shorten hospital stays for infants with bronchiolitis. This study found no significant difference in discharge time or hospital length between epinephrine and placebo groups, suggesting limited benefit for this treatment.
Area of Science:
- Pediatrics
- Respiratory Medicine
- Clinical Trials
Background:
- Bronchiolitis treatment in infants is primarily supportive.
- The efficacy of bronchodilators for bronchiolitis remains controversial.
- Previous studies on bronchodilators in bronchiolitis have been limited by small sample sizes and short-term outcome measures.
Purpose of the Study:
- To evaluate the effectiveness of nebulized single-isomer epinephrine compared to placebo in hospitalized infants diagnosed with bronchiolitis.
- To determine the impact of nebulized epinephrine on key clinical outcomes, including length of hospital stay and time to discharge.
Main Methods:
- A randomized, double-blind, controlled trial was conducted with 194 infants diagnosed with bronchiolitis.
- Participants received either nebulized epinephrine or a saline placebo at four-hour intervals.
- Primary outcomes measured were length of hospital stay and time to discharge; secondary outcomes included respiratory rate, heart rate, respiratory effort, and oxygen requirement.
Main Results:
- No significant differences were observed in overall hospital stay length or time to discharge between the epinephrine and placebo groups.
- Infants requiring supplemental oxygen and intravenous fluids had a longer time to discharge in the epinephrine group (P=0.02).
- Increased heart rate was noted after epinephrine administration, but no significant changes in respiratory rate or effort scores were found.
Conclusions:
- Nebulized epinephrine did not significantly reduce hospital stay duration or expedite discharge for infants hospitalized with bronchiolitis.
- The findings suggest that nebulized epinephrine may not be beneficial for the general management of hospitalized infants with bronchiolitis.
- Severity of illness, particularly the need for supplemental oxygen at admission, strongly predicted patient outcomes.
Background:
The treatment of infants with bronchiolitis is largely supportive. The role of bronchodilators is controversial. Most studies of the use of bronchodilators have enrolled small numbers of subjects and have examined only short-term outcomes, such as clinical scores.
Methods:
We conducted a randomized, double-blind, controlled trial comparing nebulized single-isomer epinephrine with placebo in 194 infants admitted to four hospitals in Queens-land, Australia, with a clinical diagnosis of bronchiolitis. Three 4-ml doses of 1 percent nebulized epinephrine or three 4-ml doses of normal saline were administered at four-hour intervals after hospital admission. Observations were made at admission and just before, 30 minutes after, and 60 minutes after each dose. The primary outcome measures were the length of the hospital stay and the time until the infant was ready for discharge. The secondary outcome measures were the degree of change in the respiratory rate, the heart rate, and the respiratory-effort score and the time that supplemental oxygen was required.
Results:
There were no significant overall differences between the groups in the length of the hospital stay (P=0.16) or the time until the infant was ready for discharge (P=0.86). Among infants who required supplemental oxygen and intravenous fluids, the time until the infant was ready for discharge was significantly longer in the epinephrine group than in the placebo group (P=0.02). The need for supplemental oxygen at admission had the greatest influence on the score for severity of illness and strongly predicted the length of the hospital stay and the time until the infant was ready for discharge (P<0.001). There were no significant changes in the respiratory rate, blood pressure, or respiratory-effort scores from before each treatment to after each treatment. The heart rate was significantly increased after each treatment with epinephrine (P=0.02 to P<0.001).
Conclusions:
The use of nebulized epinephrine did not significantly reduce the length of the hospital stay or the time until the infant was ready for discharge among infants admitted to the hospital with bronchiolitis.
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