<%@LANGUAGE="VBSCRIPT" CODEPAGE="1252"%> MGH Lab Handbook - Compatibility Testing Laboratory

The Compatibility Testing Laboratory on Gray 2 is responsible for all pretransfusion testing as well as the storage and dispensing of blood products. The laboratory is open 24 hours/day and 7 days/week.

1. Sample Identification: Since clerical errors are the cause of the majority of hemolytic transfusion reactions, all blood bank samples MUST be clearly and indelibly labeled with:

a. Patient’s full name
b. Patient’s unit number
c. Phlebotomist’s identification
d. Date of phlebotomy

Inadequately identified samples will be destroyed and a properly identified sample will be requested. The label on the top copy of the Blood Product Requisition (#10693) should be used as the tube label.

2. Sample Type and Volume: 10 mL of anticoagulated blood in an EDTA (lavender top) tube is the preferred specimen although 10 mL of clotted blood (red top tube) is acceptable.

3. Sample Dating: Blood bank samples may be used for three days (the draw date is day 0). Blood bank samples from same day admit patients who have not been transfused or pregnant in the preceeding three months may be used for 30 days.

4. Neonatal Sample Requirement: 10 mL of maternal blood in a 10mL EDTA tube (lavender top) AND 10mL clotted cord blood (red top tube). If both a maternal specimen or cord specimen are not obtainable, 2mL of blood in a 10mL EDTA tube (lavender top) is required. No additional sample is required for red blood cell transfusions for the next four months unless an unexpected antibody is detected in the preliminary work.

5. Type and Screen: ABO grouping, Rh typing, and an antibody screen are performed on all specimens sent to the laboratory. If an atypical red blood cell antibody is detected, antibody identification testing will also be performed.

6. Crossmatch: A crossmatch with an in-dated sample is required for all whole blood, packed red blood cells and deglycerolized red blood cells including autologous units.

7. Preoperative Blood Requests: Requests must be sent to the Blood Transfusion Service by 7:00pm the day before the scheduled surgery.

8. Non-Preoperative Blood Requests: All requests will be handled as routine unless “ASAP” or “STAT” is indicated on the requisition. The following guidelines should be used in setting the priority of requests:

a. Routine - Transfusion is required to alleviate moderate symptoms of anemia. A turnaround time of 3-5 hours is acceptable.

b. ASAP - Transfusion is required to alleviate marked clinical symptoms directly related to anemia or ongoing hemorrhage. A turnaround time of 1.5-2 hours is acceptable.

c. STAT - Transfusion is required to correct a potentially life threatening blood loss. The turnaround time of 45 minutes is the absolute minimum that is allowed for safe and complete pretransfusion testing.

d. EMERGENCY WAIVER: The need for transfusion is so acute that blood products need to be released prior to the completion of compatibility testing. The responsible physician must sign the “Emergency Waiver” form accepting the risks associated with the protocol. Compatibility testing will be completed following release of the units. Any unexpected incompatible results will be phoned to the floor immediately.

9. Release of Crossmatched Units: Crossmatch units of blood are generally held for a maximum of 24 hours. Crossmatch units for operating room requests are generally held until 7:00 am, the morning following surgery.

10. Suspected Transfusion Reaction Workup: All suspected reactions (except urticarial only) must be reported. The laboratory workup is intended to rule out clerical error, hemolysis, or red cell sensitization as the cause of the symptoms. The patient’s physician should order ancillary tests such as urinalysis, blood cultures, plasma hemoglobin or haptoglobin if clinically indicated. A report will be sent to the floor following completion of the laboratory investigation. The following should be sent when requesting a transfusion reaction workup:

a. 10 mL anticoagulated blood in a properly labeled EDTA tube (lavender top)

b. The remainder of the unit suspected of causing the reaction along with any attached I.V. tubing or solutions.

c. A completed “Suspected Transfusion Reaction Report” (Form #11603)

d. A completed Blood Product Requisition (#10693)

11. Tranfusion guidelines:

Transfusion care must be individualized to each patient.

a. Packed Red Blood Cells

1) Hct < 21 for patients without cardiovascular compromise.
2) Among physiologically stressed patients, for the prevention of ischemia:

Age < 40; Hct < 24
Age 40-60; Hct < 27
Age 60-70; Hct < 30

b. Platelets

1) Prophylactically for platelet count <10,000mm3 (adults), <20,000/mm3 (children), <50,000/mm3 (neonate<72 hours).
2) <30,000 platelets/mm3 and bleeding or minor bedside procedure.
3) <50,000 platelets/mm3 and intraoperative or postoperative bleeding .
4) <100,000 platelets/mm3 and bleeding post bypass.

If the next-day platelet count is inadequate, check the 1 hour post-transfusion platelet count.

Do NOT transfuse platelets in setting of TTP or HIT.

Platelet transfusion may not be useful in ITP, PTP, DIC, or uremia.

c. Fresh Frozen Plasma

1) Bleeding in patients with INR ≥ 2.
2) Bedside procedure and INR ≥ 2.
3) Prophylaxis (non bleeding) with INR ≥ 6.

FFP is generally not indicated for patients with INR < 1.5.

d. Cryoprecipitate

1) Bleeding in the setting of:

a) Fibrinogen < 100 mg/dL
b) Documented dysfibrinogenemia
c) von Willebrand’s disease

e. Modified Cellular Blood Components: Irradiated, Leukoreduced, CMV-seronegative:

For each of the following categories of patients, appropriate modifications (if any) of cellular blood components (RBCs and Platelets) are listed.


Category of Patient Irradiated Leukoreduced CMV-seronegative
General adult or pediatric
no no no
Family-member donors
yes no no
yes no no
Patients with a history of prior recurrent febrile non-hemolytic reactions
no yes no
Neonates < 1200 grams
yes yes no
Neonate exchange or intrauterine
yes yes no
Pregnant females who are CMV seronegative
no yes no
Hematology, non-malignant: requiring long-term transfusion support
no yes no
Hematology, malignant not undergoing stem cell transplant
yes yes no
Hematology, stem-cell transplant, when either donor or recipient is CMV seropositive
yes yes no
Hematology, stem-cell transplant, when BOTH donor and recipient are CMV-seronegative
yes yes yes, if possible
Non-liver solid organ transplant patient or candidate
no yes no
Liver transplant if either donor or recipient is CMV-seropositive
no no no
Liver transplant if BOTH donor and recipient are CMV-seronegative
no yes, in post-operative period no
HIV patients who are CMV-seropositive
no no no
Congenital T-cell immunodeficiency patients (Wiskott-Aldrich, DiGeorge, etc)
yes yes no
Patients receiving Fludarabine regardless of diagnosis
yes no no

12. When calling the laboratory to obtain patient information, please have the patient’s full name and unit number.

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This page last updated on February 13, 2006