Effect of High-Frequency Chest Wall Oscillation on the Central and Peripheral Distribution of Aerosolized Diethylene Triamine Penta-acetic Acid as Compared to Standard Chest Physiotherapy in Cystic Fibrosis: Materials and Methods

Effect of High-Frequency Chest Wall Oscillation on the Central and Peripheral Distribution of Aerosolized Diethylene Triamine Penta-acetic Acid as Compared to Standard Chest Physiotherapy in Cystic Fibrosis: Materials and MethodsTen patients (3 female and 7 male) with CF were studied in a randomized crossover design following informed consent approved by the Human Subjects Committee and Radiation Safety Committee at the University of Kansas Medical Center. The history of a positive sweat chloride test result and the presence of sinopulmonary disease confirmed the diagnosis of CF. Patients were included if they did not have symptoms of an exacerbation and had spirometry testing within 15% of their stable baseline. Exclusion criteria included hospitalization during the previous month, hemoptysis > 30 mL during the previous month, hemoptysis requiring embolization within the previous 2 months, or an FEV1 decline of > 15% from baseline. read
This pilot study utilized a crossover, within-subject comparison design. Subjects were randomized to avoid “order effect” using a predetermined block randomization scheme in groups of three, three, and four subjects. A washout period of at least 72 h but not more than 10 days was included between treatments.
The protocol for determination of aerosol deposition was based on previous studies conducted by Smaldone and Messina and Ilowite et al. In order to determine pulmonary distribution of aerosol, lung size and volume must first be established to use as a standard to compare the distribution of aerosol particles. Xe is an inert gas governed by flow properties similar to oxygen and carbon dioxide. Because of its radioactive nature, and because it distributes freely throughout the lung, Xe is commonly used to determine the alveolar volume.
In our study, patients underwent a standard equilibrium Xe scan at functional residual capacity to demonstrate total alveolar volume. Xe was administered by standard protocol via a specialized delivery system as a 10-mCi dose utilizing a low-energy, all-purpose collimator with 20% windows on Siemens under dynamic acquisition conditions. Sixty-second frames were obtained for a total of six frames. Thus, the Xe scans were conducted over time, and the composite of these scans was used to determine the average Xe distribution. Equilibrium and washout images were obtained. The highest frame count was used to define the lung borders.

This entry was posted in Cystic Fibrosis and tagged aerosol, airway clearance, central to peripheral deposition ratio, chest physiotherapy, cystic fibrosis, high-frequency chest wall oscillation, pulmonary, Xe.