Role of ventilation strategy on perfluorochemical evaporation from the lungs.
To study the effect of ventilation strategy on perfluorochemical (PFC) elimination profile (evaporative loss profile; E(L)), 6 ml/kg of perflubron were instilled into anesthetized normal rabbits. The strategy was to maintain minute ventilation (VE, in ml/min) in three groups: VE(L) (low-range VE, 208 +/- 2), VE(M) (midrange VE, 250 +/- 9), and VE(H) (high-range VE, 293 +/- 1) over 4 h. In three other groups, respiratory rate (RR, breaths/min) was controlled at 20, 30, or 50 with a constant VE and adjusted tidal volume. PFC content in the expired gas was measured, and E(L) was calculated. There was a significant VE- and time-dependent effect on E(L.) Initially, percent PFC saturation and loss rate decreased in the VE(H) > VE(M) > VE(L) groups, but by 3 h the lower percent PFC saturation resulted in a loss rate such that VE(H) < VE(M) < VE(L) at 4 h. For the groups at constant VE, there was a significant time effect on E(L) but no RR effect. In conclusion, E(L) profile is dependent on VE with little effect of the RR-tidal volume combination. Thus measurement of E(L) and VE should be considered for the replacement dosing schemes during partial liquid ventilation.
Institute of Clinical Medicine, National Yang-Ming University School of Medicine, Taipei, Taiwan, Republic of China. mjjeng@yahoo.com
M J
MJ
Jeng
D
D
Trevisanuto
C M
CM
Weis
W W
WW
Fox
A B
AB
Cullen
M R
MR
Wolfson
T H
TH
Shaffer
D000818:Animals; D001835:Body Weight / Q000502:physiology; D005466:Fluorocarbons / Q000378:metabolism*; D006439:Hemodynamics / Q000502:physiology; D021061:Liquid Ventilation; D008168:Lung / Q000378:metabolism / Q000502:physiology*; D010100:Oxygen / Q000097:blood; D010313:Partial Pressure; D011652:Pulmonary Circulation / Q000502:physiology; D011659:Pulmonary Gas Exchange; D011817:Rabbits; D015656:Respiratory Mechanics / Q000502:physiology; D013990:Tidal Volume / Q000502:physiology
D005466:Fluorocarbons; D010100:Oxygen