Transfusion Medicine Case Studies

CASE 2: Use of Blood Products

Clinical History:

The next day your surgical team responds to a Trauma One call to find an 18-year-old woman status post motor vehicle accident flown in by Air Med from a remote location. She is transfused during transport. She remains hypotensive and she is immediately taken to the operating room with obvious abdominal trauma.

  1. What blood was issued to the Air Med team?

  2. Air Med uses O-neg packed RBC's.

Further History:

The Blood Bank informs the OR that a blood sample was received which was not clearly labeled, and the Blood Bank requires a new specimen. Your intern takes the phone and tells the Blood Bank that he personally drew the sample and that the label was fine.

  1. What should you do?

  2. If the Blood Bank calls needing a new sample, get one, and label it correctly.

  3. What information is required on the specimen clot tube?

    • First and last name

    • Medical record number

    • Date and Time

    • Initials of person obtaining the sample

  4. Why is this information important?

  5. ABO incompatible transfusions are caused by clerical errors at the time a sample is obtained or when the unit is hung (patients not properly identified before transfusion).

  6. What is an appropriate course of action for hospital administration to deal with this intern?

  7. The intern is required to complete courses in risk management and employee relations in order for his contract to be renewed.

Further History:

The patient has used 8 units of O-neg packed red cells up to that point, and another 8 units of O-neg packed cells are in the OR. Another 10 units of A-neg packed cells are delivered to the OR (a total of 18 additional units available). The anesthesiologist says she does not want to use the A-neg blood because her literature recommends staying with Type O-blood after 6 units of O-blood are used on a patient.

  1. Which blood type should be given to the patient? Why?

  2. The Blood Bank issues O-negative blood in a trauma situation until the patient's blood type is determined by a properly labeled sample. Once the type is obtained, type specific blood should be used. Continuing to give type "O" blood to an "A" patient will eventually result in hemolysis, secondary to accumulation of incompatible plasma.

  3. Why might the anesthesiologist be confused?

  4. Each unit of packed RBC's contains about 40 ml of plasma. After 8 units, the patient has received around 320 ml of incompatible plasma. The "anti-A" antibody in this "O" plasma is already attached to the patient's "A" red blood cells. This amount of plasma is not sufficient to change the patient's "back type" to that of a type "O" patient.

    The anesthesiologist may be referring to the use of whole blood in trauma situations. A unit of whole blood contains about 200 ml of plasma. 8 units of type "O" whole blood would contain 1650 ml of plasma which may be enough to give the patient a type "O" "back type". Type "O" plasma contains "anti-A" which could make transfusions with type "A" red blood cells dangerous, even though the patient was type "A" to begin with.

  5. The Blood Bank may ask you for yet another clot tube in a trauma situation. Why?

  6. If this patient had received 18 units of type "O" blood, then the Blood Bank would need a new clot tube to check the patient's "back type" to be sure switching to type "A" red blood cells was safe.

Further History:

The pathologist in charge of the Blood Bank calls into the OR requesting an update on the condition of the patient. At that point in time the patient has used some fresh frozen plasma, platelets, 16 units of O-neg packed RBC's, and 15 units of A-neg packed RBC's.

  1. What decision does the pathologist have to make that requires an accurate update on the clinical condition of the patient?

  2. A pathologist must make transfusion medicine decisions based upon the clinical condition of the patient and the regional supply of blood. This patient may need to be given "A positive" blood, even if this means she may never have a successful pregnancy secondary to hemolytic disease of the newborn (because she will develop "anti-D" after the switch). It would be a tragedy to give just one D-positive unit and later find out that her injuries were not as severe as first anticipated, and after surgical hemostasis was easily obtained. For all of you wondering, it is not practical to give RhoGam to cover an entire unit of blood transfused. Decisions must also be made regarding the supply of platelets.