Breathing Parameter Measurements for Lung Deposition Simulation

The inhalation of aerosol drugs is a key element of current asthma and COPD treatment. The efficiency of the therapy is highly influenced by the dose depositing in the lungs. However, the amount of drug depositing in the lung is a result of complex drug particle-inhaler-patient interaction, thus it is inhaler-, drug- and patient-specific. Assuming that the airflow dependent aerodynamic characteristics of the drugs are known, the lung dose depends on the patient's breathing parameters during the inhalation of drug through the inhaler. In this study the inhalation parameters of asthmatic and COPD patients are measured and lung deposition assessed by a validated numerical lung deposition model. Effects of different breathing parameters (inhalation time, inhaled volume, average flow rate, peak flow rate, time until peak flow rate is reached, breath-hold time) as well as patient demographic data, disease type and disease severity on the lung dose are studied. The correlations are analysed for asthma and COPD groups separately.