ASSESSMENT OF AEROSOL DRUG DELIVERY DURING THE ESCALATION OF TREATMENT FOR A SIMULATED COVID-19 ADULT PATIENT

ABSTRACT

The effect of the various COVID-19 clinical interventions on aerosol delivery is not well known. This study investigated the use of a vibrating mesh nebuliser to deliver aerosolised drugs during mouthpiece-mediated aerosol drug delivery, high flow nasal therapy and invasive mechanical ventilation employing a low tidal volume ventilation strategy. Simulated adult healthy and mild adult COVID-19 breathing patterns were used for spontaneous breathing assessments. A mechanical ventilator delivered standard and low tidal volume ventilation parameters. The results presented represent the percentage drug delivered to a simulated healthy adult and mild adult COVID-19 patient during concurrent aerosol therapy during these interventions. The highest delivered drug dose was measured during mouthpiece-mediated aerosol therapy with a result of 57.93 %- 1.05 % for mild COVID-19, 56.64 %- 2.94 % for healthy, as a comparator. Use of HFNT resulted in the lowest percentage drug delivered (2.33 %- 0.99 % for 30 LPM;1.80 %- 0.61 % for 60 LPM), with no significant difference between the flow rates (p=0.6220). For mechanical ventilation, there was a significant difference in adopting a LTV ventilation strategy (13.66 %- 0.75 %) in comparison to a standard ventilation (30.34 %- 0.27 %) (p < 0.0001). It can be concluded that the choice of clinical intervention in the oxygenation and ventilatory support of the COVID-19 patient influences aerosol delivery to the lung. This variability may be significant and therefore should be noted in the design of dosing strategies, and de-risking of clinical trial programs. Key Message The choice of clinical intervention in the oxygenation and ventilatory support of the COVID-19 patient influences aerosol delivery to the lung. This variability may be significant and therefore should be noted in the design of dosing strategies, and derisking of clinical trial programs.