Total liquid ventilation provides ultra-fast cardioprotective cooling.
OBJECTIVE
We tested whether total liquid ventilation (TLV) can be used to rapidly cool and protect the infarcting heart.


BACKGROUND
Decreasing myocardial temperature during ischemia is a powerful cardioprotective strategy, but clinical application has been impaired by lack of practical methodology to quickly cool the heart.


METHODS
We performed 30-min coronary artery occlusion/3-h reperfusion in rabbits. Upon occlusion, rabbits underwent either oxygen (Gas), normothermic liquid (Liquid Warm), or cold liquid (Liquid Cool) ventilation.


RESULTS
Left atrial chamber temperature decreased to 32.4 degrees +/- 0.2 degrees C within 5 min of onset of cold TLV. Blood gases were within acceptable limits during TLV. In the Liquid Warm group, perfluorocarbon inhalation did not alter infarct size compared with Gas (37.7 +/- 1.3% and 42.5 +/- 4.9% of risk zone, respectively). However, infarction was significantly reduced in the Liquid Cool group (4.0 +/- 0.5%). Cooling only during the initial 30 min of reperfusion did not reduce infarction.


CONCLUSIONS
Total liquid ventilation can elicit rapid cardioprotective cooling during ischemia.
Tissier
Renaud
R
Department of Physiology, University of South Alabama, College of Medicine, Mobile, Alabama 36688, USA.
Hamanaka
Kazutoshi
K
Kuno
Atsushi
A
Parker
James C
JC
Cohen
Michael V
MV
Downey
James M
JM
D000818:Animals; D001794:Blood Pressure / Q000502:physiology; D004195:Disease Models, Animal; D005466:Fluorocarbons / Q000008:administration & dosage*; D006339:Heart Rate / Q000502:physiology; D007036:Hypothermia, Induced / Q000379:methods*; D021061:Liquid Ventilation / Q000379:methods*; D009203:Myocardial Infarction / Q000473:pathology* / Q000503:physiopathology / Q000517:prevention & control*; D011817:Rabbits; D013997:Time Factors
D005466:Fluorocarbons