Clinical Efficacy of Heated Humidified High-Flow Nasal Cannula versus Conventional Oxygen Therapy in Children Aged 2–24 Months with Bronchiolitis: A Prospective Observational Study

Abstract

Background: Bronchiolitis remains a major cause of respiratory distress and hospitalization during the first two years of life. Heated humidified high-flow nasal cannula (HHHFNC) has emerged as a non-invasive alternative to conventional low-flow oxygen, but real-world evidence from ward-based settings remains valuable. Methods: This prospective observational hospital-based study included 200 children aged 2–24 months admitted with bronchiolitis. One hundred children received conventional oxygen and 100 received HHHFNC in addition to standard supportive care. Demographic features, baseline physiological parameters, clinical signs, oxygen response, treatment failure, duration of oxygen therapy, hospital stay, referral, and mortality were compared. Categorical variables were analyzed with the chi-square test and continuous variables with Student’s t-test or analysis of variance; correlation and multivariable logistic regression were also performed. A two-sided p value below 0.05 was considered statistically significant. Results: The groups were similar in age, sex distribution, pulse rate, admission oxygen saturation, temperature, and illness duration. Both treatments rapidly improved mean SpO2, with comparable values at 1 hour and 24 hours. Treatment failure was substantially lower with HHHFNC than with conventional oxygen (9.0% versus 22.0%; p=0.012), and recovery was correspondingly higher (91.0% versus 78.0%). Referral and mortality were also lower with HHHFNC, although these differences did not reach statistical significance. Oxygen therapy and hospital stay were longer in the HHHFNC cohort. Respiratory rate predicted treatment failure in the conventional oxygen group, while no baseline predictor was significant in the HHHFNC group. Conclusions: HHHFNC was associated with lower treatment failure and higher recovery than conventional oxygen in children hospitalized with bronchiolitis. Its benefits were observed across age, sex, and clinical-sign subgroups. Optimized weaning protocols may help reduce the longer treatment and observation periods observed in routine practice.

Keywords: bronchiolitis; child; high-flow nasal cannula; heated humidified oxygen; non-invasive ventilation; oxygen saturation; respiratory rate; treatment failure