A portable electro-vibratory device may provide a safe and efficacious solution for airway clearance in patients with chronic respiratory diseases, according to a crossover pilot study.
Developed by researchers from Virgen del Rocío University Hospital in Sevilla, Spain, the device—named Electrovest—integrates neuromuscular electrical stimulation to induce contraction of the thoracic muscles to loosen mucus from the bronchial walls.
The Electrovest is portable and overcomes the limitation of commonly used systems that are based on high-frequency chest wall oscillation (HFCWO) technology. Most of these HFCWO-based systems rely on a bulky electric generator and can be expensive, according to the researchers.
“The Electrovest is expected to be a much more economical and affordable system, and importantly, it is mobile, offering greater potential reach for hypersecretory patients,” they added.
Bronchial secretion expulsion
The electro-vibratory device was evaluated in 21 clinically stable patients, of whom eight had cystic fibrosis, nine had bronchiectasis, three had COPD, and one had asthma. Each patient received two interventions, one with the Electrovest and another with the HFCWO-based system the Vest, with a 20-day washout period between interventions. Each intervention consisted of four 20-min sessions (warm-up, work, and recovery phases).
The Electrovest delivered thoracic electrical stimulation at between 4 and 8 Hz via eight electrode groups placed on the anterior and posterior chest. The Vest, on the other hand, delivered pneumatic oscillations at between 13 and 20 Hz. Both interventions were administered after broncho-dilator and saline nebulization.
Compared with the Vest, the Electrovest was rated as significantly more comfortable on the visual analogue scale (1 vs 3, with lower scores indicating greater comfort; p=0.023), with no significant difference in the quantity of sputum expelled (median, 30.70 vs 26.24 g; p=0.880). [Pulmonology 2025;31:2594888]
Treatment with the electro-vibratory device also resulted in substantial improvements in several clinical and functional parameters. Maximal inspiratory pressure rose from 100 cmH2O at baseline to 102 cmH2O post-therapy (p=0.035), the distance covered on the 6-min walk test (6MWT) increased from 560 to 578 m (p=0.005), and pectoral strength (1RM) improved from 26 to 29 kg (p=0.020). There was no evidence of muscle or renal injury.
Finally, scores on the Cough and Sputum Assessment Questionnaire (CASA-Q) indicated significant improvements from baseline in the domains of cough symptoms (p=0.016), cough impact (p=0.022), and sputum symptoms (p=0.025) with the Electrovest.
An innovative alternative
The study is the first to demonstrate that a device based on the contraction of the thoracic muscles using electrical muscle stimulation can generate an HFCWO, which is effective in eliminating secretions in patients with bronchial hypersecretion, according to the researchers.
They emphasized that the improvements in maximal inspiratory pressure and distance covered on the 6MWT not only reflect improved ventilation with the Electrovest but also its positive effect on exercise capacity.
“We believe our findings are relevant, as adherence to bronchial hygiene therapies is closely related to patient experience. A comfortable, adaptable device encourages repeated home use, improving adherence to respiratory physiotherapy,” the researchers said.
“The Electrovest’s combination of electrical stimulation and vibration, along with portability, affordability, and positive effects on functional and comfort outcomes, supports its potential as an innovative alternative to conventional home therapy and self-care programmes,” they added.