Plethysmographic estimation of thoracic gas volume in apneic mice

Janosi, Tibor Z., Adamicza, Agnes, Zosky, Graeme R., Asztalos, Tibor, Sly, Peter D. and Hantos, Zoltan (2006) Plethysmographic estimation of thoracic gas volume in apneic mice. Journal of Applied Physiology, 101 2: 454-459. doi:10.1152/japplphysiol.00011.2006

Author Janosi, Tibor Z.
Adamicza, Agnes
Zosky, Graeme R.
Asztalos, Tibor
Sly, Peter D.
Hantos, Zoltan
Title Plethysmographic estimation of thoracic gas volume in apneic mice
Journal name Journal of Applied Physiology   Check publisher's open access policy
ISSN 8750-7587
Publication date 2006-08
Sub-type Article (original research)
DOI 10.1152/japplphysiol.00011.2006
Volume 101
Issue 2
Start page 454
End page 459
Total pages 6
Place of publication Bethesda, MD, United States
Publisher American Physiological Society
Language eng
Abstract Electrical stimulation of intercostal muscles was employed to measure thoracic gas volume (TGV) during airway occlusion in the absence of respiratory effort at different levels of lung inflation. In 15 tracheostomized and mechanically ventilated CBA/Ca mice, the value of TGV obtained from the spontaneous breathing effort available in the early phase of the experiments (TGVsp) was compared with those resulting from muscle stimulation (TGVst) at transrespiratory pressures of 0, 10, and 20 cmH2O. A very strong correlation (r2 = 0.97) was found, although with a systematically (∼16%) higher estimation of TGVst relative to TGVsp, attributable to the different durations of the stimulated (∼50 ms) and spontaneous (∼200 ms) contractions. Measurements of TGVst before and after injections of 0.2, 0.4, and 0.6 ml of nitrogen into the lungs in six mice resulted in good agreement between the change in TGVst and the injected volume (r2 = 0.98). In four mice, TGVsp and TGVst were compared at end expiration with air or a helium-oxygen mixture to confirm the validity of isothermal compression in the alveolar gas. The TGVst values measured at zero transrespiratory pressure in all CBA/Ca mice [0.29 ± 0.05 (SD) ml] and in C57BL/6 (N = 6; 0.34 = 0.08 ml) and BALB/c (N = 6; 0.28 ± 0.06 ml) mice were in agreement with functional residual capacity values from previous studies in which different techniques were used. This method is particularly useful when TGV is to be determined in the absence of breathing activity, when it must be known at any level of lung inflation or under non-steady-state conditions, such as during pharmaceutical interventions.
Keyword functional residual capacity
lung volume
Boyle's law
Q-Index Code C1
Q-Index Status Provisional Code
Institutional Status Non-UQ

Document type: Journal Article
Sub-type: Article (original research)
Collection: Faculty of Health and Behavioural Sciences -- Publications
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Citation counts: TR Web of Science Citation Count  Cited 29 times in Thomson Reuters Web of Science Article | Citations
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Created: Wed, 17 Nov 2010, 11:33:27 EST