Radioaerossol Pulmonary Deposition Using Mesh in Normal Subjects

VMN (NIVO, Respironics®, Murrysville, Pennsylvania, USA) with an MMAD of 3.0 µm was placed in the elbow adapter at the mask. Inhalation was performed using diethilene triamine penta-acetic technetium (99mTc-DTPA) with radioactivity of 25 millicuries (Nobre et al., 2007). Both nebulizers were charged with 2.5 mg of salbutamol and 0.25 mg of ipratropium bromide and normal saline solution to complete a fill volume of 3 mL.

The JN (Misty Max, Air Life, Yorba Linda, USA) with a particle MMAD of 5 µm (according to the manufacturer information) was positioned in the circuit using a "T" piece placed between the circuit leak and the mask, and operated with oxygen flow at 8 L/min. Inhalation was performed using diethilene triamine penta-acetic technetium (99mTc-DTPA) with radioactivity of 25 millicuries (Nobre et al., 2007). Both nebulizers were charged with 2.5 mg of salbutamol and 0.25 mg of ipratropium bromide and normal saline solution to complete a fill volume of 3 mL.

Bilevel positive airway pressure (BiPAP Synchrony, Respironics®, Murrysville, Pennsylvania, USA) was applied through face mask (Comfort Full 2, Respironics®, Murrysville, Pennsylvania, USA) attached with straps and pressure adjusted to12 cmH2O peak inspiratory pressure and 5 cmH2O of expiratory pressure at the beginning of the procedure. Patients were adapted to use NIV before starting measurements, pressures were titrated before reaching the established levels and just after this period masks were fitted using the straps. They were oriented to use a breathing pattern inspiring deeply and exhaling slowing to avoid ventilator-patient asynchrony.