Non-Invasive Characterization of Oxygen Transport in Sickle Cell Disease: A Pilot Study
Vaso-occlusive crisis is, in part, a result of microvascular ischemic insults
to tissue causing pain in Sickle Cell Disease patients, which is a common presentation to the
Emergency Department.
This study simultaneously measured and compared several global and regional indicators
of oxygen transport in normal volunteers and subjects with Sickle
Cell Disease.
The study shows Sickle Cell Disease to share similarities with sub-clinical compensated
state of shock on a microcirculatory level.
The values obtained from the study can hopefully shed light into the intricacies of the baseline
biophysiology of Sickle Cell Disease; with a foresight to further understand
Vaso-occlusive crises pathological processes and sickled
cells interactions with its surrounding environment.
Sickle Cell Disease is a disease manifestation of a set of genetic abnormalities
primarily affecting patients of African and Mediterranean descent.
It is caused by a substitution of valine for glutamic acid in the sixth position of the beta
globin chain on chromosome
This alters the surface charge of the molecule and allows sickle hemoglobin tetramers
to polymerize inside the red blood cell.
The polymer can alter both the red cell shape and membrane properties
leading to abnormal and complex interactions with the vascular endothelium.
The combination of these effects produces a hemolytic anemia
and suspected microvascular dysfunction, which results in severe pain.
The mechanisms by which this occurs have not been well delineated,
but are likely due in part to abnormalities in oxygen transport.
Current concepts suggest several factors may impact oxygen transport including inflammation,
neurohumoral responses, autonomic nervous system adaptations and
abnormalities in vascular response.
Emerg Med Open J 2015; 1(3): 89-95. doi: 10.17140/EMOJ-1-114