Search results
Results From The WOW.Com Content Network
Red blood cell concentrates, also known as red cell concentrates or packed red blood cells, are red blood cells that have been separated for blood transfusion. [1] A red blood cell concentrate typically has a haematocrit of 0.50 – 0.70 L/L and a volume between 250 and 320 mL.
A low hematocrit level is a sign of a low red blood cell count. One way to increase the ability of oxygen transport in red blood cells is through blood transfusion, which is carried out typically when the red blood cell count is low. Prior to the blood transfusion, hematocrit levels are measured to help ensure the transfusion is necessary and safe.
Blood transfusion is ... red blood cell transfusion was considered when the hemoglobin level fell below 100g/L or hematocrit ... a maximum auto-hemolysis threshold ...
Therefore, in those with no bleeding or only "dry" bleeding, the threshold for transfusion should be between 5,000 and 10,000/μL. A more conservative threshold of 20,000/μL should be used in those with a fever or other risk factors for bleeding. Those with active bleeding or prior to surgery should have a threshold of 50,000/μL.
If the hemoglobin level falls below thresholds based on the person's clinical condition, a blood transfusion may be necessary. [122] An increased number of red blood cells, leading to an increase in the hemoglobin and hematocrit, [note 4] is called polycythemia. [126]
One unit increase in hematocrit can cause up to a 4% increase in blood viscosity. [2] This relationship becomes increasingly sensitive as hematocrit increases. When the hematocrit rises to 60 or 70%, which it often does in polycythemia , [ 4 ] the blood viscosity can become as great as 10 times that of water, and its flow through blood vessels ...
Transfusion dependent anemia is a form of anemia where ongoing blood transfusion are required. [91] Most people with myelodysplastic syndrome develop this state at some point in time. [92] Beta thalassemia may also result in transfusion dependence. [93] [94] Concerns from repeated blood transfusions include iron overload. [92]
Centrifugal sedimentation is the most used process by which erythrocytapheresis occurs. In this method, patient or donor blood is collected and processed into an erythrocyte concentrate with a high hematocrit content. This exhausted, pre-filtered blood is collected in a suitable reservoir and pumped into a rotating centrifuge.