Am. J. Respir. Crit. Care Med.,
Volume 163, Number 7, June 2001, 1605-1608
Comparative Effects of Red Blood Cell Transfusion and
Increasing Blood Flow on Tissue Oxygenation in
Oxygen Supply-dependent Conditions
PHILIPPE VAN der
LINDEN,
STEFAN
DE HERT,
SYLVAIN
BÉLISLE,
FRANÇOISE
DE GROOTE,
NATHALIE
MATHIEU,
SANDRINE
D'EUGENIO,
VALÉRIE
JULIEN,
CHIWAN
HUYNH,
and
CHRISTIAN
MÉLOT
Department of Experimental Anesthesia, Erasme University Hospital, Brussels, Belgium
Red blood cell (RBC) transfusion is usually administered to improve oxygen delivery (DO2) in order to sustain tissue oxygen demand. However, this practice is not supported by firm clinical or
experimental data. Using a randomized two-period crossover design, this study compared the efficacy of "fresh" RBC transfusion and increased blood flow to restore tissue oxygenation in oxygen supply-dependent conditions. In 12 ketamine-anesthetized mongrel dogs submitted to nonpulsatile normothermic cardiopulmonary bypass, DO2 was reduced by a progressive decrease in pump
flow. DO2 dependency was defined as an O2 uptake (
O2) decrease
by more than 15% from baseline value. Then, intervention consisted of a 40% increase in DO2 obtained either by transfusion of
"fresh" dog's RBC (stored < 3 d) or by increase in pump flow. Animals received both interventions sequentially in a random order,
while O2 saturation was maintained constant. In O2 supply-dependent conditions, rising pump flow from 1.6 ± 0.4 to 2.7 ± 0.7 L/
min increased DO2 from 5.4 ± 1.1 to 9.0 ± 1.3 ml/kg/min (p < 0.01) and
O2 from 3.5 ± 0.4 to 4.1 ± 0.5 ml/kg/min (p = 0.02).
"Fresh" RBC transfusion, which increased the hemoglobin concentration from 6.4 ± 0.9 to 11.1 ± 1.3 g/dl, increased DO2 from 5.4 ± 1.2 to 9.0 ± 1.4 ml/kg/min (p < 0.01) and
O2 from 3.6 ± 0.4 to
4.1 ± 0.5 ml/kg/min (p = 0.02). There was no difference in
O2 resulting from both interventions. In oxygen supply-dependent conditions, "fresh" RBC transfusion and increased blood flow are
equally effective in restoring tissue oxygenation.