Facemasks and aerosol delivery in vivo

Area of Science:

• Pediatric Pulmonology
• Respiratory Drug Delivery
• Medical Device Engineering

Background:

• In vitro studies indicate facemask air leaks and facial drug deposition reduce inhaled medication efficiency and can cause local side effects.
• Previous research highlights the critical role of facemask seal in optimizing aerosolized drug delivery.

Purpose of the Study:

• To validate in vitro findings regarding facemask leaks and drug delivery efficiency in vivo.
• To quantify lung and facial deposition of radiolabeled salbutamol in young children using different facemask seal conditions.

Main Methods:

• A pilot study involving eight wheezy children (18-36 months) using radiolabeled salbutamol.
• Administration via a metered-dose inhaler with a spacer and facemask, or a nebulizer with a facemask.
• Gamma camera imaging to assess drug deposition (lung, mask, and face) as a percentage of the total dose.

Main Results:

• Lung deposition was minimal (0.2%-0.3%) with non-tight facemask fits.
• Lung deposition increased with tighter fits (0.6%-1.4%) and normal breathing (4.8%-8.2%).
• Significant drug deposition occurred on the mask (0.8%-5.2%) and face (2.6%-8.4%).

Conclusions:

• In vivo results support in vitro findings: facemask leaks substantially impair drug delivery to the lungs.
• Optimizing facemask fit is essential for maximizing therapeutic benefit and minimizing facial drug deposition in pediatric patients.
• This study underscores the importance of proper device technique in ensuring effective inhaled therapy for young children.