Flashcards in Hematology, Transfusions, & Fluids Deck (69)
What is GP IIb/IIIa responsible for in hemostasis?
Aggregation of platelets by binding a crosslink, glue-like pattern of fibrinogen with the GP IIb/IIIa receptors
What are the vitamin K dependent clotting factors?
2, 7, 9, 10 Protein C, Protein S
How does plasminogen play a role in coagulation?
During crosslinking of fibrin, plasminogen is incorporated; with endothelial damage, tPA is also released to activate plasminogen into plasmin which degrades cross-linked fibrin, releasing D-dimers (keeps thrombosis in check)
What does activated clotting time (ACT) measure?
Intrinsic and common pathway coagulation cascades
Hemophilia A: what factor is missing and hereditary pattern?
Factor 8 deficiency, X-linked recessive disorder
How does DDAVP work for clotting?
Up-regulates natural production of Factor 8 and vWF (increasing levels by 2-4 times)
What is Type 1 von-Willebrand Disease? Does DDAVP help?
Less vWF (quantitative defect), DDAVP increases levels.
What is Type 2 von-Willebrand Disease? Does DDAVP help?
Weird vWF (paradoxical thrombosis), DDAVP produces more weird vWF
What is Type 3 von-Willebrand Disease? Does DDAVP help?
Extremely low vWF, DDAVP doesn't increase it enough to make a difference
Does von-Willebrand Disease increase PTT and bleeding time?
Does not routinely rise PTT but does increase BT
Would you place an epidural in a patient with von-Willebrand Disease?
Use DDAVP prior to epidural placement (no official guidelines though)
What is Humate-P?
Factor 8 and vWF concentrate
How do you expect the following lab values to change in DIC: Platelets, D-dimer, fibrinogen, INR, PTT
Decreased Plt (consumptive), increased INR/PTT (consumptive), increased D-Dimer (increased fibrin breakdown by plasmin), decreased fibrinogen
What is the pathophysiology behind Idiopathic Thrombocytopenic Purpura (ITP)?
IgG antibodies towards platelet antigens leading to platelet destruction
What should the platelet count be for major surgeries?
How much do you expect a pack of plasmapheresis platelets to increase the platelet count?
60,000 increase (6-pack)
What blood type is the universal donor for FFP?
AB, Rh + (since FFP contains no antibodies while O, Rh- has antibodies against A, B, and Rh)
What is found in cryoprecipitate?
Fibrinogen, vWF, Factor 8
What factors are found in Factor 9 Complex?
Factors 2,7,9, 10 (recall that's the same as the vitamin K factors!)
What does washing RBCs do?
Remove IgA to avoid anaphylactic reactions in IgA deficient patients
What does leukodepletion of RBCs do?
Reduction of febrile reactions and alloimmunization
What does irradiation of RBCs do?
Destroys DNA to prevent graft vs host disease
When do you normally see a delayed hemolytic transfusion reaction?
Typically in lesser antigens (Kidd, Kell, Duffy, etc.), appears a few days to weeks as an unconjugated hyperbilirubinemia and low serum haptoglobin
What is the underlying cause of febrile reactions to transfusions?
Due to recipient antibodies towards donor WBCs
Do you stop a transfusion for a febrile transfusion reaction?
No, treat conservatively
What are the two major transfusion related causes of morbidity and mortality?
Transfusion related acute lung injury (TRALI) and Transfusion associated circulatory overload (TACO)
What is TRALI? Onset of symptoms?
Capillary leak syndrome causing significant non-cardiogenic pulmonary edema (donor WBC Ab that bind recipient WBC antigens); starts within 2 hours and resolves within 48 hours
What is negative pressure pulmonary edema?
Forceful inspiratory pressure against a closed glottis -> large (-) intrathoracic pressure pulls water from interstitium to alveolus
What is transfusion associated circulatory overload?
TACO: fluid overload from products that cause a cardiogenic pulmonary edema