Session: HFNC in Bronchiolitis: Best Thing Since Sliced Bread?

Presenter: Shawn Ralston, MD

Summation: Shawn Ralston, known as “Dr. Bronchiolitis” for her work on the AAP Bronchiolitis Practice Guideline, described the limited data on the use of High Flow Nasal Cannula (HFNC) in bronchiolitis. For HFNC to be effective it must have a flow above the patient’s minute ventilation, or at least 2 LPM for the infant. Physiologic studies show that HFNC improve work of breathing by washing out dead space and providing “mini-CPAP.” Increasing flow increases the CPAP effect up to about 6 LPM with less effect at higher rates. HFNC can achieve equivalent CPAP levels of about 3-4, with higher flows increasing pneumothorax risk. Studies of HFNC in bronchiolitis have been observational and retrospective showing trends towards decrease risk of intubation and that HFNC can be safely used outside an ICU setting. There are no clear data or guidelines to indicate which patients with bronchiolitis will benefit from HFNC.

Key Points:

• Need cannula at least 50% diameter of nares;
• Mouth should be closed—can use pacifier;
• Need flow rate above estimated minute ventilation;
• Higher flow, increase pneumothorax risk;
• Need high quality studies to better understand the role of HFNC in bronchiolitis.

David Pressel is a Pediatric Hospitalist and Inpatient Medical Director at Nemours/Alfred I. duPont Hospital for Children in Wilmington, DE and a member of Team Hospitalist.