ABSTRACTS from 16th International COnference on ... - CRRT Online

Blood Transfusions are Important for the Resuscitation of the Critically Ill Patient
Educational Objectives:
Can Ince PhD
11:00-11:15
Thursday, February 16
To explain the importance of red blood cells and their hemorheological factors which determine optimal delivery
of red blood cells to the microcirculation.
Explain the importance of convective and diffusive transport of oxygen and the importance of viscosity in this
respect.
To explain that hypovolemia can indeed be corrected by fluid resuscitation but that lowering the hematocrit can
compromise the distribution and oxygen transport to the tissues.
Content Description:
When shock or hemodilution leads to a limitation in the oxygen carrying capacity of the circulation, blood transfusions
are warranted. Blood transfusions are affective in transporting oxygen to the tissues. Not only because of
improved oxygen carrying capacity due to the presence of haemoglobin, but because of its viscosity, important
in recruiting the microcirculation. Red blood cells (RBC) also have an important role in vascular regulation.
Recent studies have shown that in the presence of hypoxia RBCs release vasodilator substances such as nitric
oxide and ATP. Various reports have indicated that storage of RBCs can have deleterious effects on their ability
to transport oxygen to the tissues. Indeed recent clinical trials seem to corroborate these earlier findings. In animal
studies we had shown that citrate based storage media could adversely affect the oxygen carrying properties
of stored blood when transfused in vivo and that the use of more modern storage fluids such as SAGM did not
suffer <strong>from</strong> such effects . It should be noted that recent trials reporting that transfusion of aged RBCs are associated
with adverse clinical outcomes have used non-leuco-depleted stored blood. In clinical studies we have performed
using SAG-M stored leuco-depeleted blood we have shown that blood transfusion in cardiac surgery and
anaemic hemotological patients lead to improvement in red blood cell availability in the microcirculation and
improvement in tissue oxygenation . Nevertheless maintaining physiological hematocrit and [Hb] by blood
transfusions using leuco-depleted has been show in a recent German trial to lead to improved outcome, organ
function and length of stay. These results suggest that when storage conditions are optimized, blood transfusions
for increasing oxygen delivery to the tissues are an essential procedure in the hemodynamically compromised
critically ill patient.
Suggested Reading:
Yuruk K, Bartels SA, Milstein DM, Bezemer R, Biemond BJ, Ince C. (2011) Red blood cell transfusions and tissue
oxygenation in anemic hematology outpatients. Transfusion. Aug 29. doi: 10.1111/j.1537-2995.2011.03312.x
Raat NJH, Ince C (2007) Oxygenating the microcirculation: the perspective <strong>from</strong> blood transfusion and blood
storage. Vox Sanguin 93(1):12-8.
Yuruk K, Almac E, Bezemer R, Goedhart P, de Mol B, Ince C (2010) Blood transfusions recruit the microcirculation
during cardiac surgery. Transfusion 51(5):961-7.
Raat NJ, Hilarius PM, Johannes T, de Korte D, Ince C, Verhoeven AJ. (2009) Rejuvenation of stored human
red blood cells reverses the renal microvascular oxygenation deficit in an isovolemic transfusion model in rats.
Transfusion 49(3):427-4.
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