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Title: Airway blood flow response to dry air hyperventilation in sheep

Abstract

Airway blood flow (Qaw) may be important in conditioning inspired air. To determine the effect of eucapneic dry air hyperventilation (hv) on Qaw in sheep the authors studied 7 anesthetized open-chest sheep after 25 min. of warm dry air hv. During each period of hv the authors have recorded vascular pressures, cardiac output (CO), and tracheal mucosal and inspired air temperature. Using a modification of the reference flow technique radiolabelled microspheres were injected into the left atrium to make separate measurements after humid air and dry air hv. In 4 animals a snare around the left main pulmonary artery was used following microsphere injection to prevent recirculation (entry into L lung of microspheres from the pulmonary artery). Qaw to the trachea and L lung as measured and Qaw for the R lung was estimated. After the final injection the sheep were killed and bronchi (Br) and lungs removed. Qaw (trachea plus L lung plus R lung) in 4 sheep increased from a mean of 30.8 to 67.0 ml/min. Airway mucosal temp. decreased from 39/sup 0/ to 33/sup 0/C. The authors conclude that dry air hv cools airway mucosa and increases Qaw in sheep.

Authors:
; ;
Publication Date:
Research Org.:
Univ. British Columbia Pulmonary Research Lab., St. Paul's Hospital, Vancouver, Canada
OSTI Identifier:
5458991
Report Number(s):
CONF-8604222-
Journal ID: CODEN: FEPRA; TRN: 86-028540
Resource Type:
Conference
Resource Relation:
Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States); Journal Volume: 45:3; Conference: 70. annual meeting of the Federation of American Society for Experimental Biology, St. Louis, MO, USA, 13 Apr 1986
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; LUNGS; BLOOD FLOW; MICROSPHERES; RADIOISOTOPES; RESPIRATION; SHEEP; TRACER TECHNIQUES; TRACHEA; ANIMALS; BODY; DOMESTIC ANIMALS; ISOTOPE APPLICATIONS; ISOTOPES; MAMMALS; ORGANS; RESPIRATORY SYSTEM; RUMINANTS; VERTEBRATES; 551001* - Physiological Systems- Tracer Techniques

Citation Formats

Parsons, G.H., Baile, E.M., and Pare, P.D. Airway blood flow response to dry air hyperventilation in sheep. United States: N. p., 1986. Web.
Parsons, G.H., Baile, E.M., & Pare, P.D. Airway blood flow response to dry air hyperventilation in sheep. United States.
Parsons, G.H., Baile, E.M., and Pare, P.D. Sat . "Airway blood flow response to dry air hyperventilation in sheep". United States. doi:.
@article{osti_5458991,
title = {Airway blood flow response to dry air hyperventilation in sheep},
author = {Parsons, G.H. and Baile, E.M. and Pare, P.D.},
abstractNote = {Airway blood flow (Qaw) may be important in conditioning inspired air. To determine the effect of eucapneic dry air hyperventilation (hv) on Qaw in sheep the authors studied 7 anesthetized open-chest sheep after 25 min. of warm dry air hv. During each period of hv the authors have recorded vascular pressures, cardiac output (CO), and tracheal mucosal and inspired air temperature. Using a modification of the reference flow technique radiolabelled microspheres were injected into the left atrium to make separate measurements after humid air and dry air hv. In 4 animals a snare around the left main pulmonary artery was used following microsphere injection to prevent recirculation (entry into L lung of microspheres from the pulmonary artery). Qaw to the trachea and L lung as measured and Qaw for the R lung was estimated. After the final injection the sheep were killed and bronchi (Br) and lungs removed. Qaw (trachea plus L lung plus R lung) in 4 sheep increased from a mean of 30.8 to 67.0 ml/min. Airway mucosal temp. decreased from 39/sup 0/ to 33/sup 0/C. The authors conclude that dry air hv cools airway mucosa and increases Qaw in sheep.},
doi = {},
journal = {Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)},
number = ,
volume = 45:3,
place = {United States},
year = {Sat Mar 01 00:00:00 EST 1986},
month = {Sat Mar 01 00:00:00 EST 1986}
}

Conference:
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