[Changes in PCO2 and pH gradients in a canine model of experimental acute hemorrhage].
OBJECTIVE
To study changes in arterial-venous PCO2 pressures (Da-vPCO2) and in pH (Da-vpH) in an experimental dog model of acute bleeding. To emphasize the utility of monitoring these variables in situations of acute bleeding. ANIMALS AND METHOD: Eighteen dogs were anesthesized and monitored while being subjected to gradual bleeding. Gasometric and hemodynamic variables were recorded at the following moments: baseline, stage I (15% of volemic loss), stage Ib (20%), stage II (25%), stage IIb (30%) and stage III (35%).


RESULTS
No significant differences in pH or PCO2 in either arterial or mixed venous blood were found. Bleeding induced a constant and progressive increase in Da-vPCO2 that correlated with changes in volume (r = -0.56, p < 0.001), SvO2 (r = 0.71; p < 0.001), Da-vO2 gradient (r = 0.62; p < 0.001) and cardiac output (r = 0.63; p < 0.001).


CONCLUSIONS
Gradual bleeding caused a constant and significant increase of Da-vPCO2. Monitoring such changes in states of circulatory insufficiency may be useful for evaluating tissue ischemia.
Rabanal
J M
JM
Departamento de Anestesiología y Cuidados Intensivos, Hospital Universitario Marqués de Valdecilla, Santander.
Mons
R
R
Galindo
M
M
Solares
G
G
Seco
I
I
García-Castrillo
L
L
D000208:Acute Disease; D000771:Anesthesia, Intravenous; D018686:Anesthetics, Intravenous / Q000008:administration & dosage; D000818:Animals; D001794:Blood Pressure; D002245:Carbon Dioxide / Q000097:blood; D003975:Diazepam / Q000008:administration & dosage; D004195:Disease Models, Animal; D004285:Dogs; D005260:Female; D006439:Hemodynamics; D006470:Hemorrhage; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008297:Male; D008991:Monitoring, Physiologic; D010313:Partial Pressure; D012771:Shock, Hemorrhagic / Q000503:physiopathology
D018686:Anesthetics, Intravenous; D002245:Carbon Dioxide; D003975:Diazepam