RESPIRATORY STUDIES

Respiratory Safety Pharmacology as described in ICH S7A core battery aims to evaluate the effects of a test substance on pulmonary function.

The basic procedure uses whole body plethysmography. Several supplementary and follow-up studies can be designed to further evaluate the effects on respiratory function.

Whole body plethysmography

Inter-group comparison: no indication = not significant; ** = p < 0.01; *** = p < 0.001

Respiratory parameters:

- Inspiratory Time (Ti, ms)
- Expiratory Time (Te, ms)
- Peak Inspiratory Flow (PIF, ml/s)
- Peak Expiratory Flow (PEF, ml/s)
- Tidal Volume (TV, ml)
- Respiratory Rate (ResR, breaths/min)
- Relaxation Time (Tr, ms)
- Pause = (Te - Tr)/Tr
- Enhanced Pause (Penh) = Pause x PEF/PIF
- Minute volume (MV, ml/min) = (TV x ResR).

Examples of follow-up studies

> Airway function under modified or pathophysiological conditions in small animals (juvenile animals, hypercapnia, bronchoconstriction, cough etc.)
> Pulmonary arterial blood pressure (anesthetized or conscious large animals)
> Isolated trachea preparations