Radioaerosol Pulmonary Deposition During Asthma Exacerbation Through Noninvasive Ventilation

Analysing the Effects of Coupling Nebulization to Noninvasive Ventilation Through Pulmonary Scintigraphy on the Radioaerosol Deposition During Asthma Exacerbation

Despite the physiologic and clinical effects provided by coupling nebulization with noninvasive ventilation in asthma exacerbation, there are few and controversial studies reported in the literature.

Reduced work of breathing, increased oxygenation and increased in expiratory peak flow (EPF) and forced expiratory volume in the first second (FEV1) are benefits of noninvasive ventilation (NV) in the treatment of asthma. Despite these clinical improvements attributed to NV during asthma exacerbations and the well-established effects of nebulization, there are few studies in the literature coupling both therapeutic resources.

In addition to this, no studies on scintigraphic analysis of radioaerosol deposition coupled with NV in asthmatics have published. A previous study was published by our group, but involved healthy subjects.

Inclusion Criteria:

• Clinical diagnosis of moderate to severe asthma (FEV1 < 60 % of predicted values)
• Breathing rate > 25 bpm
• History of asthma for at least 1 year
• Duration of current asthma attack of < 7 days
• Reversibility of FEV1 of at least ≤ 10% after the administration of bronchodilator drugs

Exclusion Criteria:

• Current smoker
• Presence of cardiopulmonary disease (COPD, pneumonia, heart failure, myocardial infarction, pneumothorax)
• Hyperthermia
• Indication of intubation and invasive mechanical ventilation;
• Hemodynamic instability (heart rate > 150 bpm and systolic blood pressure < 90 mmHg)
• Cardiac arrhythmia
• Changes in consciousness
• Pregnancy
• Contraindications to use NV