NASHVILLE, TENN. — Heliox may have a beneficial effect when used to deliver racemic epinephrine to young children with bronchiolitis, suggest the results of a randomized controlled trial.
Investigators found that children treated with epinephrine and heliox improved significantly more than those treated with epinephrine and oxygen, Dr. In Kim reported in a poster presented at the annual congress of the Society of Critical Care Medicine.
“The mixture of helium and oxygen delivers nebulization deeper and faster into the lungs and has been shown to ease the work of breathing in adults,” Dr. Kim, a pediatric emergency physician at Kosair Children's Hospital in Louisville, Ky., said in an interview. “This would also be very important for these little ones, in whom more work of breathing can lead to fatigue and even respiratory failure.”
The study involved 69 children aged 2–12 months, all of whom still had a Modified Wood's Clinical Asthma Score of at least 3 after an initial treatment of nebulized albuterol. The patients were randomized to nebulized racemic epinephrine delivered either by heliox (70% helium/30% oxygen) or 100% oxygen using a face mask. After the nebulization, all patients continued receiving their randomized treatment via a nasal cannula, which Dr. Kim said is more tolerable than a face mask for young children.
After 60 minutes of treatment, children whose bronchiolitis scores were 2 or higher received another dose of the nebulized racemic epinephrine, followed by continued inhalation via nasal cannula.
By 60 minutes, children receiving the drug via heliox had improved significantly more than those receiving the drug by oxygen. “The difference was significant early on and continued to grow,” said Dr. Kim. By 240 minutes or at ED discharge, the mean change in the bronchiolitis score was 1.84 for the heliox group and 0.31 for the oxygen group—a highly statistically significant finding.
The findings almost exactly mirror those of a similar trial conducted in Spain in 2002. “We did not have a difference in length of stay, as the Spanish study did, but it also included sicker patients than ours. This supports the theory that the sicker the patient is, the greater the benefit of heliox,” Dr. Kim said.
The Spanish study included 38 young children and infants aged 1–24 months who were admitted to the pediatric intensive care unit with respiratory syncytial virus bronchiolitis (Pediatrics 2002;109:68–73). Those randomized to nebulizer and inhalation therapy with heliox had a significantly larger mean decrease in bronchiolitis scores since the beginning of the study (4.2 points), than did children in the oxygen group (2.5 points). Pediatric intensive care unit length of stay was significantly shorter in the heliox group than in the oxygen group (3.5 days vs. 5 days).
Dr. Kim did not disclose any financial conflicts.