Noninvasive pulmonary function screening in spontaneously breathing rodents: An engineering systems perspective

Noninvasive pulmonary function measurements made on rodents are commonly used for studies where quick, relatively easy end-points are required. These types of measurements are of particular advantage for studies where large numbers of animals are involved. Using tests that are simple to administer generally translates to more efficient and more accurate data collection. Noninvasive measurements result in less stress placed on the animal and allow repeated testing of the same animals at multiple time points. This review focuses on several noninvasive methods that have been developed for pulmonary function screening, which are analyzed from an engineering systems perspective. An analog model of the respiratory system of a conscious, freely respiring animal is presented in terms of an equivalent electrical circuit. This model is used as a basis to demonstrate the relationship between pulmonary parameters derived from circuit analysis.