Blood, Anemia Flashcards
What are the components of the CPDA1 Preservative?
1) Citrate: Chelates Calcium, disrupting clotting mechanism
2) Phosphate: Buffer
3) Dextrose: energy source for cellular metabolism
4) Adenine: Substrate source for cells to produce ATP
-Extends shelf life to 35 days
-Preserves blood and prevents coagulation
What is the difference in shelf life between CPD (without adenine) vs CPDA1?
CPD (without adenine): 2 weeks
CPDA1: 35 days
What are the benefits of Component Therapy?
Maximizes the number of recipients and preserves function of essential blood elements.
What are the basic purposes of transfusing each component?
-Packed RBCs: oxygen carrying capacity
-Platelet concentrates: thrombocytopenia
-Fresh frozen plasma: coagulation proteins
-Cryoprecipitate: Fibrinogen, Factors VIII vWF, XIII
-Leukocyte poor RBCs: filtration to remove WBCs
Describe the process of separating blood components:
1) First centrifuge at room temperature produces platelet concentrates
-By separating plasma (containing platelets) from RBCs
2) Then the other products are separated by centrifuging at cold temperatures (1-6˚ C)
Describe PRBCs with CPDA-1
Hct 70-75%
50-70 mL of residual plasma
Volume 250-275 mL
Shelf life 35 days
-Similar pH and K+ content to additive solution
Describe PRBCs with Additive Solution:
Hct 60%
Less plasma (10-15 mL)
Volume 250-350 mL
Less citrate
Longer shelf life–42 days
Regenerates 2,3-DPG more quickly
Less TRALI
-Similar pH and K+ content to CPDA-1
1 unit of PRBCs should increase Hgb by ___ g/dL or the Hematocrit by approx. ____%
1 unit of PRBCs should increase Hbg by 1g/dL or the hematocrit by approximately 3%
Describe biochemical changes that occur in stored PRBCs.
1) pH decreases to 6.7 by 21 days
2) K+ = 4 mEq day of donation → 76 mEq at 35 days (slow leak of K+ from banked blood)
3) Dextrose:
-Day of donation raises blood sugar to 400 mg/dL
-At 35 days glucose level drops to 100 mg/dL
4) Decreased 2,3 DPG:
-Levels at 10% of baseline at 35 days, left shift in Oxy-Hgb curve
What is 2,3 DPG?
A compound that binds deoxyhemoglobin and increases oxygen delivery to cells).
-Decreased levels shift oxyhemoglobin dissociation curve to the left (increased O2 affinity for Hgb)
- 2,3 diphosphoglycerate and it comes from glycolysis
What are saline-washed RBCs?
For patients who experience reactions to foreign proteins that attach themselves to RBCs
-↓allergic reactions due to IgE or IgA antibodies
-Washed with isotonic saline solution
-Resulting units must be transfused within 24 hours
What are Leukocyte-reduced RBCs?
-Filtration or irradiation
-Done to eliminate or reduce white blood cell passengers
-Prevent non-hemolytic febrile transfusion reactions
What is the Hgb level that triggers transfusion?
There is NO transfusion trigger or Hgb level at which to transfuse.
What is Chronic Anemia?
-S/Sx begin to develop at a Hgb of <7/8 g/dL
Compensatory mechanisms:
-Increased cardiac output
-Increased 2,3 DPG so that oxygen unloads at lower oxygen saturation of hemoglobin
-Healthy bone marrow can increase production up to 6-fold
Decision to transfuse depends on pt’s underlying health status, the s/sx of decompensation due to anemia, cardiorespiratory reserve, and activity level
Chronic anemia patients rarely require transfusion until Hgb levels drop to 5g/dL overwhelming compensatory mechanisms.
Tolerance of acute anemia depends on what?
-Maintenance of intravascular volume
-Ability of the patient to increase cardiac output
-Health of the patient
What is the major function of RBCs (erythrocytes)?
To transport Hemoglobin.
-The bound hemoglobin carries oxygen from the lungs to the tissues of the body.