Issuing Blood in Emergencies

In emergencies, when blood is urgently required for transfusion, it is sometimes necessary to issue blood before pretransfusion testing can be completed. As well, massive transfusion has unique problems that requires its own protocols. Also, because periodic blood shortages exist, it is sometimes necessary to switch ABO groups and issue red cells (or plasma) that are not ABO specific. When this occurs, following acceptable protocols is crucial to patient safety. Several variations of these protocols exist. Below are general guidelines.

Patient's ABO group and Rh(D) Type are Known

hotlink This protocol is for patients whose blood groups are known because they have been tested on this admission. Past records of any kind do not qualify the patient as having a "known" blood group.

hotlink If at all possible, issue ABO and Rh(D) specific donor red cells.

hotlink Perform an IS crossmatch at RT or do an electronic crossmatch to confirm ABO compatibility between patient and donor.

hotlink Before issuing, ensure that the ABO type of donors and Rh(D) type, if Rh negative, have been confirmed.

Patient's ABO group and Rh(D) Type are Unknown

hotlink If possible, determine patient's ABO and Rh(D) type and issue ABO and Rh-specific donor units as above.

hotlink If time does not allow, issue group O Rh(D)- negative concentrated red cells.

hotlink Before issuing, ensure that the ABO and Rh(D) type of donors have been confirmed.

hotlink Depending on lab policy, perform an IS crossmatch at RT (or an electronic crossmatch) as appropriate.

hotlink If plasma is required, issue group AB plasma.

Massive Transfusion

Massive transfusion is defined as transfusing a blood volume equal to or exceeding the patient's volume. In an adult this is typically 8 to 10 units of concentrated red cells. When this happens, transfusion services institute special protocols.

hotlink Abbreviated crossmatching (immediate spin at RT or electronic crossmatch) is used for patients without unexpected antibodies. It does not make sense to continue to crossmatch with the patient's pretransfusion blood specimen, which no longer represents in vivo conditions; neither does a newly drawn specimen in the patient who continues to be massively transfused represent in vivo conditions. This protocol is designed for labs that routinely do IAT crossmatches for patients with negative antibody screens.

hotlink For patients with clinically significant antibodies, physicians will need to decide whether to transfuse red cells that are antigen-negative, or whether the urgency of transfusion over-rides this normal protocol.

hotlink Policies should be in place for when to switch blood groups, should there be an inadequate supply of blood of the patient's blood type. See below (Switching Blood Groups) for more details.

hotlink Additional protocols exist that relate to bleeding problems due to dilution of coagulation factors and platelets; citrate toxicity and hypokalemia; and cardiac toxicity from rapid transfusion of cold blood. See standard textbooks in Suggested Reading for a discussion of these issues. Also see the Enrichment Activity below.

Switching Blood Groups

Switching blood groups may become necessary in these circumstances:

hotlink Red cells of the patient's ABO group are unavailable.

hotlink Red cells of the patient's Rh(D) type are unavailable.

hotlink Plasma of the patient's ABO group is unavailable.

Enrichment activity #6

Go to this trauma Web page about massive transfusion. Besides "blood volume replacement," list the complications of massive transfusion that are discussed at this site. E-mail responses to Pat.

Electronic Crossmatch Emergencies Issuing Blood Products