Red Blood Cell Transfusion A Pocket Guide for the Clinician Robert Weinstein, MD University of Massachusetts Medical School November 2016 Adapted from Red Blood Cell Transfusion: A clinical practice guideline from the AABB, Clinical Practice Guidelines from the AABB: Red blood cell transfusion thresholds and storage, and additional sources Red Blood Cells as a Therapeutic Product Irradiation Prevention of TA-GVHD in certain Radiation dose: 2500 circumstances cGy to center of product Appropriate uses of red blood cell (RBC) transfusion Donor categories Gamma or • Treatment of symptomatic anemia Product donated by family member X-irradiation • Prophylaxis in life-threatening anemia Product from HLA-selected donor Shelf life of irradiated Products from directed donors • Restoration of oxygen-carrying capacity in case of hemorrhage product: up to 28 whose relationship to recipient’s • RBCs are also indicated for exchange transfusion days unless original family has not been established w Sickle cell disease expiration date is w Severe parasitic infection (malaria, babesiosis) Pediatric practice sooner w Severe methemoglobinemia Intrauterine transfusion (IUT) NB: Supernatant K+ w Severe hyperbilirubinemia of newborn Exchange or simple transfusion in may be higher than neonates if prior IUT usual RBC transfusion is not routinely indicated for pharmacologically treatable Congenital immune deficiency Allogeneic HPC states anemia such as: transplant recipient: • Iron deficiency anemia Acute leukemia: HLA-matched or Start with initiation of • Vitamin B12 or folate deficiency anemia family-donated products conditioning regimen Continue throughout Dosage and administration Allogeneic hemopoietic progenitor cell period of GVHD • One unit of RBC will raise the hemoglobin of an average-size adult (HPC) transplant recipient prophylaxis by ~1 g/dL (or raise HCT ~3%) Allogeneic HPC donor 7 days prior to, Usually for at least • ABO group of RBC products must be compatible with ABO group of or during, HPC harvest 6 months recipient Until lymphocytes Autologous HPC recipient 9 • RBC product must be serologically compatible with the recipient are > 1 x 10 /L (see Pretransfusion Testing). Exceptions can be made in Hodgkin disease Indefinitely if treated for chronic emergencies (see Emergency Release of Blood Products). History of treatment with purine GVHD • Rate of transfusion analogues and related drugs w Transfuse slowly for first 15 minutes Fludarabine Autologous HPC recipient w Complete transfusion within 4 hours (per FDA) 2CDA (Cladribine®) Deoxycoformycin (Pentostatin®) 7 days prior to, and Clofarabine (Clolar®) during, harvest Major Red Cell Products for Transfusion Bendamustine (Treanda®) Initiation of Nelarabine (Arranon®) conditioning Most RBC products are derived by collection of 450-500 (±10%) mL of whole blood through 3 months from volunteer donors and removal of the plasma by centrifugation (see History of treatment with post transplant (6 Table 1). After removal of the plasma, the resulting product is red blood cells alemtuzumab (anti-CD52) months if TBI was (referred to informally as “packed red blood cells”). Aplastic anemia on rabbit anti- used) thymocyte globulin The most commonly available US RBC product has a 42-day blood bank shelf life and HCT 55-65%. Pretransfusion Testing Table 1. Special Processing of RBC for Transfusion Prevents incompatible red cell transfusion Process Indications Technical • Compatibility of donor red cells and recipient plasma Considerations • Avoid immune hemolytic transfusion reactions in the recipient Leukocyte Decrease risk of recurrent febrile, Most commonly Reduction nonhemolytic transfusion reactions achieved by filtration Pretransfusion blood sample from the intended recipient Decrease risk of cytomegalovirus Usually soon • Usually EDTA tube (plasma and red cells) (CMV) transmission (marrow after collection • Proper labeling of the sample transplant) (prestorage) w 2 independent patient identifiers Decrease risk of HLA-alloimmunization May be performed w Identity of the phlebotomist Does not prevent transfusion- at bedside w Date and time of sample collection associated graft-versus-host disease <5x106 leukocytes per w Sample rejected without these (TA-GVHD) product (per FDA) • Age of the sample Washing Decrease risk of anaphylaxis in Wash fluid is 0.9% w Up to 3 days if hospital inpatient or, in past 3 months, recipient (removes IgA-deficient patient with anti-IgA NaCl ± dextrose - Has been pregnant residual antibodies Shelf life of washed - Has been transfused plasma) Decrease reactions in patients with RBCs - Has uncertain history of either history of recurrent, severe allergic 24 hours at 1-6°C or anaphylactoid reactions to blood 4 hours at 20-24°C w Longer (often 1–2 weeks, according to hospital policy) for product transfusion May lose 20% of outpatient red cells in washing pre-op testing if negative history within 3 months process Table 2. Pretransfusion Testing • Blood bank unable to determine presence or absence of underlying alloantibodies Test Purpose Reagents Time • All RBC units are crossmatch-incompatible ABO Group & Determine if recipient’s Test recipient’s red ~25 min Rh Type blood group Rho(D) is cells with anti-A, anti-B, Balance of risks positive or negative anti-D; test recipient’s • Severe anemia requiring transfusion support * plasma with A1 and • Possibility of hemolytic transfusion reaction due to undiagnosed B cells underlying alloantibodies Antibody Detect unexpected, Test recipient’s plasma ~50 min Principles of approach to this situation Screen clinically significant with phenotyped • Communication between bedside clinician and transfusion service (non-ABO) anti-RBC “reagent” RBCs physician is essential antibodies in recipient’s plasma w Obtain careful history of prior transfusion or pregnancy - If history negative, probably safe to transfuse ABO-compatible Antibody Identify specificity of Test recipient’s plasma Varies: RBCs Identification anti-RBC antibody if with many “reagent” Hours - If history positive or uncertain, assess risk:benefit of delaying antibody screen is pos RBCs to days transfusion to complete testing Immediate Ensure ABO Test recipient’s plasma ~10 min w Assess how long it may take for blood bank or reference lab to Spin compatibility between with sample of red cells complete pretransfusion testing Crossmatch recipient’s plasma and from product chosen w Agree on best approach to choosing among incompatible RBC (when antibody RBC product chosen for transfusion units (transfusion physician will advise) screen is for transfusion negative) • Attempt to mitigate need for immediate transfusion: bed rest, oxygen Full Serological Ensure full serological Test recipient’s plasma Up to Crossmatch compatibility between with sample of red an hour Ultimately, do not deprive a patient with autoimmune hemolytic anemia (when antibody recipient’s plasma and cells from product of a needed, lifesaving transfusion screen is RBC product chosen chosen for transfusion. • Autoantibody will shorten survival of transfused RBCs and patient’s positive) for transfusion Includes extra endogenous RBCs to a similar extent incubations (e.g. at • Most undetected alloantibodies will cause delayed hemolytic 37°C and with Coombs reagent). transfusion reactions w May be misdiagnosed as worsening of autoimmune hemolysis Electronic Match ABO/Rh Validated blood bank ~10-15 w Not usually life-threatening Crossmatch compatible RBC from computer system. min • Bedside team must be hypervigilant for acute intravascular inventory with patient (not universally whose ABO/Rh status hemolytic reaction during transfusion (see Adverse Effects of available) has been confirmed Transfusion) and who has no history of, and negative testing Red Blood Cell Transfusion for, RBC alloantibodies Table 3. RBC Transfusion Recommendations* for Hospitalized, Hemodynamically Stable Patients in Specific Clinical Situations *A1 is the most common subgroup of Group A Clinical Potential Transfusion Strength of Quality of Emergency Release of Blood Products Situation Threshold Recom- Supporting mendation Evidence An emergency release of blood products is warranted when the clinical setting precludes waiting for completion of pretransfusion and Adult Inpatients, Hgb** ≤ 7 gm/dL Strong Moderate compatibility testing. Examples include: Hemodynamically Stable • Severe, ongoing life-threatening hemorrhage • Life-threatening anemia ICU Patients, Hgb ≤ 7 gm/dL Strong High What you should do: Hemodynamically Stable (adult or • Notify blood bank of need for emergency release of RBCs pediatric) • Complete hospital’s “emergency release” form w Documents your declaration of a transfusion emergency Postoperative Hgb ≤ 8 gm/dL§ Strong Moderate w U.S. federal regulations require 2 specific items on the form Orthopedic or or for symptoms† Cardiac Surgery - Statement of the nature of the emergency (e.g. “massive GI Patients hemorrhage”) - Signature of MD or “equivalent”; (PA, NP, RN, etc. cannot sign) Cardiovascular Hgb ≤ 8 gm/dL‡ Strong Moderate • Send patient blood sample to blood bank ASAP (before emergency Disease or for symptoms† transfusion begins, if possible) Acute Coronary AABB does not Uncertain Very Low Syndrome recommend for or against What you’ll get from the blood bank (depending on how much testing has a liberal or restrictive RBC already been performed): transfusion strategy • Uncrossmatched RBCs (ABO group-specific if determined on a current blood specimen) All Patients Guided by symptoms as Weak Low • Group O RBCs