Blood Transfusion and Red Blood Cells

Red Blood Cells

• Main indication for use: Patient hemoglobin is < 8g/dL and/or hematocrit is < 25%
• 1 unit of Whole Blood or Packed RBC can increase hemoglobin by 1g/dL and hematocrit by 3-5%
• Whole blood provides blood volume expansion and RBC mass in acute blood loss; for actively bleeding patients who have lost at least 25% of their blood volume, or patients requiring exchange transfusions

Storage and Transport

• Whole blood: ACD and CPD = 21 days, CPDA-1 = 35 days
• When whole blood is not available, reconstitute whole blood by mixing RBCs with thawed AB type plasma from a different donor

Packed RBCs

• Indication: Increase RBC mass in symptomatic, normovolemic patients, including oncology patients undergoing chemotherapy or radiation therapy, trauma patients, dialysis patients, premature infants, and patients with sickle cell anemia
• Preparation: 80% of plasma removed from whole blood, hematocrit: 65-80% (not exceeding 80%)
• Storage and Transport: Open system: 24 hours, Close system: ACD and CPD = 21 days, CPDA-1 = 35 days

Leukocyte-Reduced RBCs

• Indication: Increase RBC mass in patients with severe and/or recurrent febrile transfusion reactions due to leukocyte antibodies
• Preparation: Filtration (within 24 hours from time of collection) or apheresis; saline washing
• Must retain 85% of original RBCs; 1 unit contains ≥ 6.2 x 10^10 RBCs
• Should not be used if visible aggregates present; may contain residual RBCs
• Usually pooled

Platelets

Guidelines for the Effectiveness of Platelet Transfusion

• Corrected Count Increment for Platelets: Good increment: ≥ 7,500, Refractoriness: < 5,000
• Percent Recovery: 66% at 1 hour, 48% at 24 hours

Plateletpheresis Unit or Single Donor Platelet (SDP)

• Indication: For thrombocytopenic patients alloimmunized to HLA or platelet antigen (donor should be HLA matched)
• Preparation: Apheresis
• Storage: 5 days with constant agitation
• 1 unit contains ≥ 3.5 x 10^11 platelets, equivalent to 4-6 units of random donor platelets

Leukocyte-Reduced Platelets

• Indication: Same as Single Donor Platelet (SDP) or Plateletpheresis unit
• Preparation: Filtration or apheresis processing
• Storage: Open system: 5 days with agitation, Apheresis: 5 days with agitation

Granulocyte

• Main indication for use: Patients with absolute granulocyte count of < 500
• Indication: Patients with granulocyte dysfunction or myeloid hypoplasia who are unresponsive to antibiotics; severe neutropenia with infection non-responsive to antibiotic therapy
• Limited to septic infants
• Preparation: Apheresis; uses hydroxyethyl starch (HES) as sedimenting agent
• 1 unit contains ≥ 1 x 10^10 granulocytes, platelets, and 20-50 mL of RBCs

Plasma and Derivatives

• Main indication for use: PT is < 15 seconds, aPTT is < 1.5 times normal, fibrinogen is < 100 mg/dL

Fresh Frozen Plasma

• Indication: Bleeding patients who require factors II, V, VII, IX, and X
• Replace isolated factor deficiencies when specific component is not available
• Reverse effects of Warfarin (Coumadin; Panwarfin; Sofarin) anticoagulant drug
• Treatment of thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome
• Patients with liver disease to prevent or correct bleeding
• Antithrombin III deficiencies; disseminated intravascular coagulation when fibrinogen is < 100 mg/dL
• Preparation: Thawed plasma from FFP, thaw in water bath at 30°-37°C for 30-45 minutes
• Transfuse immediately, store at 1°-6°C for up to 24 hours or store at 4°C for up to 5 days if factor VIII is not needed

Leukoreduction and Washing

• Leukoreduction filters: used to remove 99.9% of WBC from RBC and platelet products
• Leukoreduced RBC: filters can reduce number of leukocytes in a bag while being transfused
• Leukoreduced Random Donor Platelet (RDP): filters can reduce number of leukocytes in a bag while being transfused
• Washing: RBC and platelets can be washed to remove plasma and reduce allergic reactions

Apheresis

• Blood is drawn from a donor or a patient and separated into components; one or more of the components is retained, and the remaining constituents are recombined and returned to the individual
• Types: Erythrocytapheresis, Plateletpheresis or thrombocytapheresis, Leukapheresis, Plasmapheresis
• Total protein of donor must not be less than 12 g/dL

Irradiation

• Using X-rays or gamma rays to inactivate WBCs and prevent graft-versus-host disease
• For whole blood, RBC, granulocytes, and platelets
• Irradiate up to 28 days of collection and stored for another 28 days
• Minimum dose: 2,500 cGy at the center of the unit, 1,500 cGy at other parts of the unit

Recombinant DNA Technology

• A process of recombining two DNA fragments from different species and inserting such recombinant molecule into a host organism in order to produce new genetic combinations that are of value in medicine, science, and industry

Transfusion Reactions and Complications

• IV line must be kept open with crystalloid in case immediate treatment is necessary to overcome hypotension.
• Attending physician and blood bank must be notified as soon as possible in case of a reaction.

Workup

• Clerical check of compatibility tag on blood bag, blood bag label, and patient identification for discrepancies.
• Examination of pre-transfusion clotted blood specimen, EDTA anticoagulated post-transfusion blood specimen, and blood bag.
• Perform Gram's stain on blood in the bag and culture if necessary to determine bacterial contamination.

Transfusion-Transmitted Diseases

• Infectious diseases that can be transmitted through blood transfusion:
  • HIV
  • HCV
  • HBV
  • HTLV
  • Syphilis
  • Cytomegalovirus
  • Trypanosoma cruzi
  • West Nile Virus

Transfusion Reactions

• Immediate effects:
  • Hemolytic reactions:
    • Fever, chills, flushing, nausea, dyspnea, chest pain, flank pain, hypotension, shock, hemoglobinemia, hemoglobinuria, DIC, renal failure.
    • Treatment: avoid human error, use well-written procedure manuals, and use highly trained clinical and laboratory staff.
  • Febrile non-hemolytic transfusion reaction (FNHTR):
    • Chills, fever, and urticaria.
    • Treatment: premedicate with antipyretics, administer antipyretics, and transfuse leukocyte-reduced products.
  • Anaphylactic reactions:
    • Flushing of the skin, abrupt hypertension followed by hypotension, substernal pain, dyspnea, nausea, abdominal cramps, emesis, diarrhea.
    • Treatment: give immediate treatment with epinephrine, IV corticosteroids, and O2 therapy.
  • Transfusion-related acute lung injury (TRALI):
    • Chills, fever, nonproductive cough, dyspnea, cyanosis, bilateral pulmonary edema, severe hypoxemia, hypotension.
    • Treatment: use proper donor selection, give respiratory support, steroids, and diuretics.
• Non-immunologic effects:
  • Iron overload or transfusion-associated hemosiderosis:
    • Multiple transfusions.
  • Hepatitis:
    • NANB, occasionally.
  • Acquired immune deficiency syndrome:
    • Host response to agent in donor blood.
  • Protozoan infection:
    • Malaria parasites.

Delayed Transfusion Reactions

• Hemolytic reactions:
  • Fever, decreased hemoglobin, mild jaundice.
  • Treatment: give antigen-negative blood for subsequent transfusions.
• Post-transfusion purpura:
  • Profound self-limiting thrombocytopenia, generalized purpura.
  • Treatment: use corticosteroids, therapeutic plasma exchange, and high-dose intravenous immunoglobulins.
• Transfusion-associated graft-versus-host disease:
  • ACUTE: fever, diffuse skin rash, diarrhea, infection, abnormal liver function, pancytopenia, usually fatal.
  • CHRONIC: fever, scleroderma-like disease, Sicca syndrome, interstitial pneumonitis, malabsorption.
  • Treatment: irradiate all blood components containing lymphocytes with a dose of 25 Gy before transfusion to susceptible individuals.
• Transfusion-induced hemosiderosis:
  • Muscle weakness, weight loss, mild jaundice, fatigue, cardiac arrhythmias, mild diabetes, growth retardation in children.
  • Treatment: administer deferroxamine, and super or hypertransfusion of neocytes.