Delivery of L-Epinephrine by Metered-Dose Inhaler Compared to Racemic Epinephrine by Nebulizer for the Treatment of Croup.

BACKGROUND

Racemic epinephrine is standard of care for moderate to severe croup. Metered-dose inhaler (MDI) was the most adopted method to replace nebulization during the SARS-CoV-2 pandemic. No study has previously evaluated the effectiveness of l-epinephrine MDI for the treatment of croup in an emergency department as compared to nebulized racemic epinephrine.

OBJECTIVE

We aim to demonstrate that l-epinephrine by MDI is effective and safe in the treatment of croup compared to racemic epinephrine. Our primary outcome was the requirement of additional doses of epinephrine.

METHODS

We conducted a retrospective, single-center study of pediatric patients 1-10 years of age diagnosed with croup from March 2020 to July 2023. We included patients who received either l-epinephrine metered-dose inhaler (LEM) or racemic epinephrine by nebulization (REN) for the treatment of croup. Data for l-epinephrine was collected prospectively.

RESULTS

There were 325 patients analyzed of which patients in 38 encounters were treated with LEM. The median age for patients was 2.6 years (IQR: 1.6, 4.4) and 75% were male. Respiratory viral testing revealed 14% positive for SARS-CoV-2. Patients that received LEM showed an improvement in Westley Croup Score (WCS) of 2 (IQR: -3, -2) at 30 minutes post-administration. When comparing LEM to REN, there was no statistical difference in need for repeat dosing, change in heart rate, return to care within 48 hours, or admission to the hospital.

CONCLUSION

In this study of l-epinephrine administered by MDI we did not observe any statistically significant differences compared to nebulized racemic epinephrine in the treatment of croup.