Determining when enhanced pause (Penh) is sensitive to changes in specific airway resistance.
Frazer-DG; Reynolds-JS; Jackson-MC
J Toxicol Environ Health, A 2011 Jan; 74(5):287-295
Penh is a dimensionless index normally used to evaluate changes in the shape of the airflow pattern entering and leaving a whole-body flow plethysmograph as an animal breathes. The index is sensitive to changes in the distribution of area under the waveform during exhalation and increases in a nonlinear fashion as the normalized area increases near the beginning of the curve. Enhanced pause (Penh) has been used to evaluate changes in pulmonary function and as a method to evaluate airway reactivity. However, the use of Penh to assess pulmonary function has been challenged (Bates et al., 2004; Lundblad et al., 2002; Mitzner et al., 2003; Mitzner & Tankersley, 1998; Petak et al., 2001; Sly et al., 2005). The objective of this study was to show how Penh of the thorax and plethysmograph flow patterns are related. That relationship is used to describe the conditions under which whole-body plethysmograph Penh measurements can be used to detect changes in sRaw.
Air-flow; Air-monitoring; Plethysmographs; Plethysmography; Animals; Breathing; Whole-body-counters; Measurement-equipment; Pulmonary-function; Airway-resistance; Thorax
David G. Frazer, National Institute for Occupational Safety and Health, Health Effects Laboratory Division, Pathology and Physiology Research Branch, Mail Stop L2101, 1095 Willowdale Road, Morgantown, WV 26505 USA
Journal of Toxicology and Environmental Health, Part A: Current Issues