Emergency-use spacers: a considerable option for asthmatic patients

Pressurized metered dose inhalers (pMDIs) spacers improve delivery by reducing hand-breath coordination requirements.

This study aimed to assess the efficacy of emergency-use and conventional spacers.

a multi-arm, parallel-group, randomized trial in which 108 asthmatics were randomized to 9 groups (pMDI alone and various spacers); each received 400 µg salbutamol. Emitted dose on the ex vivo filter was quantified using high-performance liquid chromatography. Pulmonary absorption was assessed via urinary salbutamol at 0.5 h post-dose (USAL0.5) and spirometry changes was assessed via forced expiratory volume in 1 second (FEV₁) and its percent of predicted (∆FEV₁ and ∆FEV₁% predicted), and forced vital capacity (∆FVC).

While the pMDI alone group yielded the highest ex vivo deposition (325.4 µg, P ˂0.001), it showed the lowest USAL0.5 (4.13 µg, P ˂0.001-0.032) and ∆FEV₁ (0.12 L, P ˂0.001). Among all tested devices, the Aerochamber, Able, and Tips-Haler spacers demonstrated superior performance (ex vivo filter: 207.1, 181.1, 167.5 µg, P ˂0.001-0.02; USAL0.5: 11.61, 11.15, 10.73 µg, P ˂0.001-0.09), ∆FEV₁: 0.32, 0.29, 0.31 L, respectively, P ˂0.001-0.06), with no significant difference between the three spacers, except the Aerochamber showed a significantly higher ex vivo result (P ˂0.001-0.02). DispozABLE and Lite-Air showed moderate efficacy, whereas the Atomizer, showed the lowest pulmonary function performance with varied significance across devices.

This study emphasizes the significance of spacer design. It supports the use of validated emergency-use spacers in low-resource or emergency settings where conventional devices are not available. The trial was registered at ClinicalTrials.gov, identifier: NCT06816342.