Blood Products Flashcards
What are the five main components of blood?
Red Blood Cells, White Blood Cells, Platelets, Coagulation factors, Plasma
Blood Type A
Red Cell Type: A
Antigens: A-Antigens
Antibodies: Anti-B
Blood Type B
Red Cell Type: B
Antigens: B-Antigens
Antibodies: Anti-A
Blood Type AB
Red Cell Type: AB
Antigens: AB-Antigens
Antibodies: N/A
Blood Type O
Red Cell Type: O
Antigens: N/A
Antibodies: Anti-AB
Coagulation type and pathways
Coagulation is a cell based process that occurs via a cascade. Its pathways are intrinsic (12,11,9,8), extrinsic (7,3), and common (10)
Platelet Count Levels
Normal: 150,000-400,000/mm3
Thrombocytopenia: 400,000/mm3
Activated Clotting Time (ACT)
Measures the amount of time required for whole blood to clot in a test tube
Used to monitor heparin therapy in the OR
Normal – 70-180 seconds
Sufficient for CPB –> 400 seconds
Prothrombin Time (PT)
Normal 10-14s or 30-40s (depending on reagent used)
PT test varies in sensitivity among laboratories
Partial Thromboplastin Time (PTT)
Normal 25-38s
Can be used to monitor anticoagulation therapy
International Normalized Ratio (INR)
developed to standardize PT values to better monitor oral anticoagulation therapy
Type and Screen
Recipient’s blood has been typed for A, B, and Rh antigens and screened for common antibodies
Type and Cross-Match
Recipient’s blood is incubated with the donor blood product
Clumping occurs if the cross-match is incompatible
Factors that determine when to transfuse
Extensive blood loss
Inadequate perfusion
Low hemoglobin concentration
Poor coagulation
When do you know if you need to give blood products?
For the average 70 kg patient who has lost ~1L – 1.5L of blood, send off coagulation studies and start documenting lab values and coagulation status
Packed Red Blood Cell Therapy
Indicated for treatment of anemia (often associated with blood loss)
1 unit contains 250-300 mL volume with a hematocrit of 70-80%
When to give PRBC’s
Evidence of Rapid Acute Hemorrhage w/o immediate control
Estimated blood loss >30-40%, presence of symptoms of severe blood loss
When to use crystalloid/colloid resuscitation
Estimated blood loss 20-30%
How much does 1 unit of PRBC increase hemoglobin and hematocrit
Hemoglobin: 1 g/dL
Hematocrit: 3%
Washed PRBC’s
Centrifuged in saline to remove plasma and cytokines
Once washed, PRBCs can be stored for no longer than 24 hrs
Leukocyte-reduced PRBCs
Centrifuged, washed, or filtered
- To avoid nonhemolytic febrile reactions
- To prevent sensitization of patients with aplastic anemia
- To minimize transmission of HIV or CMV
Irradiated PRBCs
Cells are exposed to a standard dose of ionizing radiation
Irradiated blood is for people who are not capable of mounting a counterattack and neutralizing transfused lymphocytes
Cell Saver
Blood salvaged from the surgical field
Hematocrit ~ 65-70%
When to give a platelet transfusion
Usually not indicated during surgery unless the platelet count is less than 50,000/mm^3