Investigation of Acute Hemolytic Transfusion Reactions (immune)

IMPORTANT: When beginning an investigation, because similar symptoms may occur in several types of complications, all possibilities must be investigated. As patient history, clinical presentation and laboratory results accrue, a differential diagnosis is carefully assessed from which the ultimate diagnosis emerges.

Transfusion services should have clear policies describing the required investigation for transfusion complications. Below is an example of a protocol suitable for laboratory investigation of an adverse event such as an immediate/acute hemolytic transfusion reaction. Individuals should always adhere to the policies developed by their institutions.

• Immediate actions
• Laboratory investigation

Laboratory Investigation

Policies and procedures for investigating suspected hemolytic transfusion reactions will vary among transfusion services. As a minimum, the following should be done in accordance with laboratory policies and procedures:

• Check for clerical errors by:
  - reviewing patient identity on the compatibility label (tag)
  - Confirming that patient and donor have compatible blood types
  - Ensuring that the correct tag is attached to the correct blood product container
  - Retrieving the patient's pre-transfusion specimen and request form/worksheet and checking that the information on both is identical and that they match the compatibility tag
• Inspect the patient's post-transfusion specimen for visible hemolysis
• Perform a Direct Antiglobulin Test (DAT) on the patient's post-transfusion specimen
• Depending on results, investigate further and report as appropriate

Further Serological Investigation

Depending on the results of the initial investigation, the transfusion service will perform follow-up serologic testing according to its own policies and procedures. Some examples are outlined under further testing.