High-Flow Nasal Cannula Therapy for Infants With Bronchiolitis

Does use of high-flow nasal cannula (HFNC) treatment in infants with bronchiolitis improve hospital length of stay and the need for treatment escalation?

HFNC treatment is appropriate for infants younger than 24 months with bronchiolitis. Compared with low-flow oxygen, use of HFNC treatment results in a modest reduction in length of hospital stay (ie, by 0.65 days) and need for treatment escalation with no significant difference in adverse events.¹ (Strength of Recommendation: B, inconsistent or limited-quality patient-oriented evidence.)

Bronchiolitis is a common lower respiratory tract illness affecting infants younger than 24 months and is the most common cause of hospitalization in infants.¹ Conventional treatment includes intravenous fluids, supplemental oxygen, and respiratory support. The authors of this Cochrane review assessed the effects of HFNC treatment compared with conventional respiratory support in the care of infants with bronchiolitis.

This Cochrane review included 11 studies comparing HFNC treatment to low-flow oxygen therapy.¹ HFNC treatment was defined as heated, humidified oxygen delivered through a nasal cannula at greater than 4 L/min; most studies described using a weight-based formula with starting flow rates at 1 to 2 L/kg per minute. Low-flow oxygen was delivered via a range of devices, including nasal prongs, face mask, and head box. Participants were all younger than 24 months with clinically diagnosed bronchiolitis in various hospital settings. The primary outcomes evaluated were length of hospital stay and adverse events. The secondary outcomes analyzed included changes in mean respiratory rate, changes in mean heart rate, need for treatment escalation, and duration of oxygen therapy or other respiratory support.

Low-certainty evidence demonstrated that HFNC treatment may reduce the length of hospital stay compared with low-flow oxygen therapy (mean difference [MD] = −0.65 days; 95% CI, −1.23 to −0.06; seven studies; n = 1,951) with little to no difference in adverse events.¹

Low-certainty evidence showed that HFNC treatment may reduce respiratory rates at 4 to 6 hours (MD = 6.3 breaths/min lower; 95% CI, 11.4–1.3 lower).¹ Moderate-certainty evidence showed that HFNC treatment may reduce heart rate at 4 to 6 hours (MD = 9.7 beats/min lower; 95% CI, 17.9–1.5 lower).

Moderate-certainty evidence showed that HFNC treatment compared with low-flow oxygen may decrease treatment escalation rates (risk ratio = 0.55; 95% CI, 0.39–0.79; absolute risk difference = 10.5%; number needed to treat = 10; eight studies; n = 2,215). Escalation was variously defined but included transitioning to continuous positive airway pressure or intubation from HFNC or low-flow oxygen treatment to one of the previously mentioned modalities. Low-certainty evidence showed that it may reduce oxygen use duration (mean duration = 0.59 days lower; 95% CI, 1.0–0.18 lower; seven studies; n = 2,132). The review was limited by significant study heterogeneity in age cutoff (6–24 months), treatment location (emergency department, inpatient settings, pediatric intensive care unit), and the level of flow rates used for HFNC treatment.

Existing guidelines from the American Academy of Pediatrics and National Institute for Health and Care Excellence do not make recommendations about the use of HFNC treatment in infants with bronchiolitis.^2,3 In a 2023 meta-analysis, which included fewer studies, HFNC compared with low-flow oxygen treatment was not associated with a reduction in hospital stay length or a reduction in escalation to mechanical ventilation.⁴ Further studies should work to reduce heterogeneity and consider whether the use of HFNC treatment results in cost savings.