CCP 107 Transfusion Medicine Flashcards
Febrile non-hemolytic reaction
- Increase in temperature <1°C above baseline without other new symptoms
- occurs in approximately 1:300 transfusions
- Treatment includes close observation, antipyretics, serial vital signs, and continuation of transfusion if the patient remains stable
Hemolysis or bacterial contamination
- Increase in temperature >1°C above baseline or an incremental increase <1°C above baseline with new symptoms such as chills, hypotension, nausea or vomiting, back pain, coagulopathy, DIC, or renal failure
- Treatment includes antipyretics, blood cultures, possible culture of the blood products, and possible empiric antimicrobials, particularly if the patient is neutropenic
Allergic symptoms during transfusion
- Urticaria: If isolated dermatologic symptoms resolve following antihistamine administration, resume transfusion.
- Systemic allergic reaction: If more systemic allergic findings including ear-nose-throat, respiratory, or cardiovascular symptoms arise, stop transfusion and treat with antihistamines, corticosteroids, and possibly epinephrine
Respiratory symptoms during transfusion
- Possible TACO, TRALI, septic transfusion reaction, or anaphylaxis.
- Symptoms may include dyspnea, bronchospasm, tachypnea, or hypoxia.
- TRALI pulmonary edema similar to ARDS, typically occurs within 6 h of transfusion.
- Treatment is guided by the severity of the symptoms as well as findings on CXR and IVC ultrasound.
- Obtain blood cultures and initiate IV antimicrobials if septic process is suspected.
- Exercise particular vigilance for the development of volume overload in the setting of impaired cardiac contractility or extreme age, which may require diuresis or nitrates
Commonly encountered transfusion-related electrolyte disturbances
- Hypocalcemia related to citrate-preservative chelation of serum calcium.
- Hypokalemia related to hepatic metabolism of citrate to bicarbonate, with an associated intracellular shifting of serum potassium.
- Hyperkalemia related to K+ accumulation in product d/t degredation during storage of blood products
types of delayed transfusion reactions (days to weeks post transfusion)
can occur days or weeks following treatment
- Delayed (extravascular) hemolytic transfusion reaction
- Post-transfusion purpura
- Graft-versus-host disease
- Viral transmission
PRBC type O/Rh-negative blood
“O neg”
- universal donor
- type A and B blood group antigens are absent in donor RBCs, thereby averting potential hemolytic reactions in response to recipient antibodies
PRBC Type O/Rh-positive blood
- universal in males
- should be avoided in females with future reproductive capacity to prevent Rh sensitization and its potential impact on future pregnancies.
PRBC Leukocyte reduction
includes the removal of WBCs, typically by filtration, which inhibits febrile transfusion reactions from WBC-associated cytokines, prevents sensitization to human leukocyte antigens found on WBCs that may present issues in patients requiring bone marrow transplantation, and decreases the risk of intracellular transmission of viruses such as cytomegalovirus.
PRBC Irradiation
assists in preventing graft-versus-host disease by hampering the ability of donor T lymphocytes to proliferate, which is important in immunocompromised patients (including transplantation patients), neonates, or and patients receiving directed donations.
PRBC washing
- assists in attenuating hypersensitivity reactions to plasma, which is important in patients with underlying IgA-deficiency syndromes.
- Caused by IgA in plasma transfused to IgA-deficient recipients with existing anti-IgA antibodies
The Pooled platelet “6-pack”
- Volume 330-360 mL
- ~300 x 109 platelets
- Whole blood derived platelet concentrates from 4-6 donors are pooled to create an effective dose. This led to platelets being called “6-pack” or “4-pack”
- increases the risk of both disease transmission and transfusion reactions
A single-donor (apheresis) unit of platelets
- Volume 230-250 mL
- ~370 x 109 platelets
- Apheresis platelet units do not need to be pooled
- current transfusion standard for platelets.
Fresh Frozen Plasma (FFP)
- FFP is distilled from whole blood following the removal of PRBCs and platelet components.
- Transfusion is usually blood type-specific, although Rh compatibility is not typically required
- Type AB is the universal donor type for plasma because type O plasma contains preformed antibodies for blood group A and B antigens
- Thawing of FFP takes 20-40 min; once thawed, it must be transfused within a few days or discarded
- FFP is utilized for the replenishment of coagulation factors, either broadly or specifically, when a particular factor concentrate is not immediately available
Cryoprecipitate
- Cryoprecipitate is the protein fraction of FFP containing cold-insoluble components
- The principal role is fibrinogen replenishment, particularly in the setting of bleeding and a fibrinogen level <100 mg/dL
- 10 units of cryoprecipitate raise the fibrinogen level by approximately 100 mg/dL
Plasma-derived factor concentrates (fibrinogen + PCC’s)
- Derived from pooled human plasma
- Fibrinogen concentrate is utilized for congenital disorders with fibrinogen deficiency.
- Prothrombin complex concentrates (PCC’s) contain varying concentrations of vitamin K-dependent clotting factors: Factors II, VII, IX, and X.
Hypothermia in transfusion
- Each unit of blood reduces the core temperature by 0.25°C.
- Use a fluid warmer and warming blanket (Bair hugger or ReadyHeat) to minimize risk.
Hypocalcemia in transfusion
- Plasma contains citrate, which chelates calcium.
- Frequently check ionized calcium levels and replenish calcium as necessary (general rule is 1g every 4 units of product)
Immunologic transfusion reactions
Cytokine release, antibody-mediated
Infectious transfusion reactions
Bacterial (Yersinia enterocolitica), viral, or rarely, others such as prion (Creutzfeldt-Jakob) or parasitic (babesiosis) agents.
Physical transfusion reactions
Hypothermia, volume overload (TACO)
Chemical transfusion reactions
Electrolyte disturbances related to blood product administration (hypocalcemia or hyper/hypokalemia most common)
Hyperkalemia in transfusion
is related to accumulation during storage of blood products.
Hypokalemia in transfusion
is related to hepatic metabolism of citrate to bicarbonate, with an associated intracellular shifting of serum potassium.
Hypocalcemia in transfusion
is related to citrate-preservative chelation of serum calcium.
Risk of HIV or hepatitis transmission in transfusion in Canada.
exceedingly low, although not zero, due to donor and donor blood screening protocols
how much does 1x unit PRBC’s raise Hgb?
~10 g/L
How much does a single apheresis unit of platelets (single donor) raise the platelet count by
~50 k.
Normal total blood volume in a 70-kg adult
approximately 75-80 mL/kg body weight or 5-5.5 L
site of RBC production in human body
Bone marrow
what is the function of Erythropoietin
produced by the kidneys, stimulates marrow to produce RBC precursors
Anemia definition
a reduced concentration of RBCs, resulting in an inadequate oxygen supply to the tissues
How long do Mature RBCs circulate in the body
for 110-120 days
