Lung function response to bronchodilator nebulization via hood in wheezy infants: A pilot study

Background: In infants, small volume nebulizers with a face mask are commonly used to facilitate aerosol therapy. However, infants may be disturbed by mask application, causing poor mask-to-face seal and thus reducing the dose delivered. Objectives: To compare lung function response to bronchodilator nebulization via two delivery devices: Hood versus mask. Methods: We studied 26 recurrently wheezy infants aged 45.8 weeks (95% confidence interval 39.6-52.0). Inhalations of 0.30 mg/kg salbutamol were administered in two alliqots 30 minutes apart using mask and hood in alternating order (M+H or H+M). Response to inhalations was measured by maximal expiratory flows at functional residual capacity (V'maxFRC) at 5 minute intervals after each dose, and area under the V'maxFRC curve (AUC) was documented. Results: A small but significant response to salbutamol was observed following the second inhalation with V'maxFRC, improving by 31.7% (7.2-56.2, P < 0.02) and AUC by 425 %·min (-154, 1004; P < 0.02). The improvement following salbutamol was similar by both delivery modalities but with a small but significantly better response when H was used after M (P < 0.01). Conclusions: Nebulized salbutamol induced a variable but positive response in wheezy infants. Salbutamol via hood was as effective as conventional face mask delivery. Since it is simple and patient-friendly, it could replace the face mask method particularly with uncooperative infants.