Determining when enhanced pause (Penh) is sensitive to changes in specific airway resistance.
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.
Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, West Virginia 26505, USA. dgf1@cdc.gov
David G
DG
Frazer
Jeffrey S
JS
Reynolds
Mark C
MC
Jackson
D000403:Airway Resistance / Q000187:drug effects; D000465:Algorithms; D000818:Animals; D016085:Bronchoconstrictor Agents / Q000633:toxicity; D016210:Methacholine Chloride / Q000633:toxicity; D008954:Models, Biological; D010993:Plethysmography, Whole Body; D012123:Pulmonary Ventilation; D012120:Respiration Disorders / Q000139:chemically induced / Q000175:diagnosis* / Q000503:physiopathology; D012137:Respiratory System / Q000187:drug effects / Q000503:physiopathology; D012720:Severity of Illness Index
D016085:Bronchoconstrictor Agents; D016210:Methacholine Chloride