Aerosol therapy during mechanical ventilation: an international survey

To describe the practice, knowledge and beliefs about aerosol therapy during mechanical ventilation in an international sample of physicians working in intensive care units (ICU). A self-administered survey was emailed to physicians who worked regularly in ICUs. The physicians were identified from the databases of the European and French societies of intensive care medicine and the REVA network. Of the 1,192 responses (15 % response rate), 854 were analyzed. Of the respondents, who represented 611 departments in 70 countries, 99 % reported using aerosol therapy during mechanical ventilation (including non-invasive), 43 % exclusively used nebulizers and 55 % also used metered dose inhalers. Nebulization relied on jet, ultrasonic and vibrating mesh nebulizers (55 %, 44 % and 14 % of respondents, respectively). Bronchodilators and steroids were the most frequently delivered drugs, and 80 % of respondents had a positive opinion concerning nebulized colistin and 30 % reported the use of nebulized antibiotics at least every other month. During nebulization, ventilator settings were never changed by 77 % of respondents, 65 % reported placing a filter on the expiratory limb, and of these 28 % never changed it. Only 22 % of respondents using heated humidifiers reported turning them off during nebulization. Specific knowledge about droplet size and nebulization yield was poor. A majority of respondents (87 %) thought that ultrasonic nebulizers outperform jet nebulizers, while 69 % had no opinion concerning mesh nebulizers. Aerosol therapy during mechanical ventilation is used by over 95 % of intensivists, mostly for bronchodilator and steroid administration, but also frequently for antibiotics. The current scientific knowledge about optimal implementation seemed infrequently applied, suggesting the need for educational programs and research focusing on a better bench-to-bedside transfer of knowledge.