TRANSFUSIONS IN SPECIAL CLINICAL SETTINGS

OUTPATIENT TRANSFUSION

• Outpatient transfusions are supported at OHSU.
• Ordering, obtaining and transfusing blood products done in the same way as for inpatients.
• Observe outpatient for at least 30 minutes before discharge.
• Insure that the patient understands the signs and symptoms of transfusion reaction before being discharged.

Outpatients Receiving Blood Products

The table below gives information regarding some possible side effects of transfusion. Most reactions to blood are minor and the benefits usually outweigh the risks.

*Reactions occur immediately or within a few hours. 

INTRAUTERINE & EXCHANGE TRANSFUSIONS

Good planning, proper communication and timely consultation with the Transfusion Medicine medical staff are crucial for safe and efficient procedures.

• Only a maternal sample is required for intrauterine transfusions.
• For exchange transfusion in neonates, maternal and a fetal sample are preferred. If unable to obtain maternal sample, contact bloodbank..
• Physician must:
• Indicate intrauterine or exchange transfusion.
• Give transfusion service maternal antibody history if outside case.
• Specify the time and date when procedure will take place.
• Procedures should be scheduled during regular working hours when possible.
• Notify Transfusion Service immediately if time changes.
• Specify volume of red blood cells needed.
• Specify desired hematocrit of final product.
• Specify other blood products needed (e.g. platelets, plasma, etc.).
• Hemoglobin S Trait-negative, washed, irradiated, leukoreduced red cells are used.
• Units outdate 24 hours after washing.
• Unit(s) provided at ambient temperature or warmer and blood warmer not required.
• Consultation with the Transfusion Medicine Service is encouraged.
• Product available 2 hours after receipt of maternal specimen. Complex antibody identification may take more time. See also Sample Requirements.
• See also Sample Outdating Neonates.

INFANT/NEWBORN TRANSFUSIONS

• Red cell products must be compatible with any significant maternal alloantibodies.
• Platelets and Frozen Plasma should be ABO/Rh compatible with the infant.
• Volume-reduced platelets are available on special order only.
• Donor exposures are limited by dosing from same unit when possible.
• Infants less than 4 months old automatically receive group O Negative, leukoreduced, HgbS-, irradiated products.
• Small volume transfusions are taken from blood not more than 42 days old (RCN).
• Large volume transfusions (>60 ml) are taken from units not more than 5 days old to minimize potassium toxicity.
• If fresh units unavailable and requesting >60 ml, blood bank may substitute washed or freshest units available.
• See also Sample Requirements.
• See also Sample Outdating Neonates.

NEONATAL ALLOIMMUNE THROMBOCYTOPENIA(NAIT)

Background.

Maternal antibodies to platelets cross placenta and cause severe antenatal thrombocytopenia. Sensitization can occur during gestation or delivery and may affect firstborn children. Maternal platelet count remains normal. Incidence is estimated at 1:2,000 live births. Severity varies from mild to severe. Disorder self-limiting and resolves in 2-3 weeks. Intracranial hemorrhage reported in 10-30% of cases with approximately half occurring in utero.

Diagnosis

• Unexplained thrombocytopenia in a newborn suggests diagnosis.
• Maternal antiplatelet alloimmunization diagnosed by demonstration of specific antiplatelet antibodies.
• Testing is sent to an outside laboratory.
• Maternal and paternal samples are preferred.
• Genotype of fetus (and by inference the phenotype of the platelets) can be determined by DNA typing of fetal cells obtained by amniocentesis.
• Fetal blood sample for platelet count may be obtained by cordocentesis as early as 20 weeks gestation however this is associated with increased risk of fetal demise.
• Check with laboratory for specimen requirements.
• Red Cross maintains a list of donors whose platelets lack common antigens targeted by NAIT patients. These can often be obtained on relatively short notice.
• In emergencies, maternal platelets are usually effective if another suitable donor cannot be found.
• Contact transfusion service for assistance.

ALLOIMMUNE HEMOLYTIC ANEMIA(AIHA)

Useful Diagnostic Tests

• Serial complete blood count, reticulocyte count, and review of cell morphology,
• Serum lactic dehydrogenase,
• Serum bilirubin; and
• Serum haptoglobin.

Serological Findings in AIHA

*IAT = Indirect Antiglobulin Test

Results in Patients with in AIHA

*PCH = Paroxysmal Cold Hemoglobinuria

Sokol, R.j., et al. Br Med J 282:2023, 1981.

Management

• Autoantibody can complicate compatibility test and obscure presence of coexisting alloantibodies.
• Autoantibody itself may cause marked shortening of donor red cells survival.
• Blood should never be denied when there is a justifiable need, but less risky course often to withhold blood transfusion in some settings in which the initial clinical judgment would suggest transfusion.
• Avoid over-transfusion because larger red cell mass post-transfusion can precipitate DIC.
• Transfusion of comparatively small volumes with patient's hemoglobin maintained just at tolerable level may be optimal means of minimizing danger of transfusion-induced intravascular hemolysis.

TRANSFUSING PATIENTS WITH SICKLE CELL & OTHER HEMOGLOBINOPATHIES

Background.

• Sickle Cell Disease (SCD), Sickle-Thalassemia, etc. pose difficult management problems.
• Recurring vaso-occlusive complications cause substantial damage across nearly all organ systems over time.
• Recurrent acute chest syndrome may lead to disabling chronic lung disease and right heart failure.
• Accumulation of silent CNS ischemia robs some patients of subtle neurologic and intellectual capacity even in the absence of clinically overt stroke.
• Premature and progressive degeneration of the femoral head contributes immense morbidity to the lives of many patients old enough to experience this complication.
• Recurrent priapism in men and the many morbid complications of pregnancy in women cause extreme suffering.
• Alloimmunization to minor red cell antigens has long been a severe, even life-threatening, problem for up to 36% of SCD patients.
• Chronic transfusion probably most physiologic method of treating sickle cell disease short of marrow transplantation.
• The complications of lifelong transfusions should be born in mind and discussed with the patient before embarking on a course of chronic transfusion management.

Management

• Patients with SCD should receive red cell units known to be HgS negative.
• Transfusion service recommends red cell phenotyping after initial diagnosis and suggests the use of RBCs matching for C, c, D, E, e and K for all SCD patients after the development of 1 red cell alloantibody.
• Consider maintenance of percent HbS below 30 because chronic transfusion therapy dramatically decreases the risk of recurrent stroke, probably to less than 10%.
• Management of SCD is controversial and still under study.

ABO MISMATCHED BONE MARROW & SOLID ORGAN TRANSPLANTS

Major ABO Mismatch

• Exists when donor marrow cells and the recipient plasma are ABO incompatible.
• This is not an absolute barrier to successful transplantation.
• When ABO-incompatible bone marrow is injected, donor marrow cells are purged of red blood cells to prevent immediate hemolytic reactions.
• Host hemagglutinins may remain in plasma for months after transplant.
• Direct antiglobulin test (DAT) may become positive after about 3 weeks if substantial numbers of donor red cells enter the circulation.
• Late hemolysis may develop due to lysis of donor red cells.
• Persistence of Anti-A and/or Anti-B in high titer may delay graft erythropoiesis.
• Recipients are transfused with group O red cells until plasma is compatible with new donor cells.

Minor ABO mismatch

• Exists when donor possesses hemagglutinins capable of reacting with ABO antigens on the recipient's red cells (e.g., group O donor and group A recipient).
• Donor lymphocytes may mount an immune response against host red cells antigens, leading to the development of a hemolytic syndrome 12 weeks after grafting (passenger lymphocyte syndrome).
• Syndrome has also been reported after transplantation of kidney, liver, lung, pancreas and spleen.
• Onset is usually abrupt and may be associated with a substantial fall in hemoglobin with signs of intravascular hemolysis.
• Management usually consists of transfusion of group O red cells.
• Exchange transfusion with group O red cells is occasionally required.
• It is logical to minimize transfusion of minor ABO-incompatible plasma including platelet products when hemolysis is occurring.

TRANSFUSION WITH INCREASED RISK OF HEMOLYSIS

Background.

At times, technical factors interfere with the crossmatch and compatible blood cannot be found. Under these conditions, the Transfusion Service staff is contacted, determines the degree of increased risk, consults with the clinical team and directs the transfusion service to issue blood with an increased risk warning. Products are issued with tags noting increased risk and special circumstances. The transfusing physician must evaluate the patient need versus the increased risk. Under these circumstances, we recommend that:

• Make sure that the reason for transfusing units with increased risk is clearly documented in medical record.
• When possible, transfusions should be done on day shift when medical and nursing staffing are optimal.
• If possible, avoid infusion during general anesthesia as symptoms of a developing reaction can be masked.
• Under most circumstances, house officers should refer the decision to transfuse to their attending staff.

Transfusions with Above-Average Risk.

1. Chronically transfused patient with no alloantibody(s), recently transfused, intermittently positive Direct Antiglobulin Test (DAT), hemolysis, and positive eluate.
2. Antibody to infrequent antigen and no typing sera.
3. Positive DAT, no recent transfusion, and patient on drug associated with positive DAT.
4. Incompatible crossmatch and positive DAT (direct antiglobulin test [Direct Coombs]).
5. Patient with known allo- or auto-antibody(s) and recently transfused (within 3 weeks) with additional positive reactions to reagent or donor cells, and/or not explained by disease or drug administration.
6. History of previous transfusion or pregnancy, recent transfusion, unexplained positive DAT, positive eluate.

Recommended Management.

Increased Risk Transfusions : (Definition A, B or C above):

• Transfuse slowly.
• Verbally check patient every 20-30 minutes for symptoms.
• Follow hematocrit for appropriate rise in 12-24 hours.
• Send sample to lab in 48-72 hours if appropriate rise not sustained in absence of known blood loss or chemotherapy regimen.

Extreme Risk Transfusions : (Definition D, E or F above):

• May use In-Vivo Crossmatch for infusion (See IN VIVO CROSSMATCH PROCEDURE ).
• Physician or nurse observes patient closely during transfusion
• Infuse product slowly.
• Stop infusion if signs of transfusion reaction develop.
• Follow hematocrit for appropriate rise and for duration of cell survival over 24-48 hours.
• Contact Transfusion Medicine for consult as needed.
• Blood products identified with increased risk will be so noted on the chart copy of the blood product requisition.