Addenda: Aug. 11 & 14, 2009

Can a blood bank computer system can be used for 'electronic' or 'computer' crossmatching if the computer system does not have a 'vendor-implemented computer crossmatch'

A blood bank supervisor at a hospital in the central valley of California wonders if a blood bank computer system can be used for 'electronic' or 'computer' crossmatching if the computer system does not have a 'vendor-implemented computer crossmatch'. Their laboratory uses a blood bank computer system that can be configured and validated by the user to perform a computer crossmatch. However, they are concerned if there are any specific federal or state (CA) regulations that would prohibit such action by a user. Is any colleague aware of a federal, state or local regulation that would preclude using a blood bank computer system for computerized crossmatching, assuming the necessary validation was done and documented in appropriate detail?

The following comments were submitted in response to the above.

1. A very experienced transfusion service computer software consultant whose office is located in a sunbelt state comments that as long as the following steps are taken, it should be permissible to locally validate a blood bank computer system for an Electronic Crossmatch (EXM):

   Protocol requires that requisite pre-transfusion patient blood grouping/typing is always performed and that the computer system can store those results and make them available for inquiry and comparison against ABO/Rh of donor RBC units.
   
   Protocol requires that a search of each pre-transfusion patients' record is done to reveal any positive antibody screen results (past or current).

   Some systems do all of the above automatically and advise (or warn) the operator if the patient is acceptable (or not) for EXM...this is probably preferable. As long as proof (documentation) can be shown (to the inspectors) that the system was adequately tested and validated for the EXM, she thinks that should be sufficient.

2. According to Suzanne H. Butch, MA, MT(ASCP)SBB at the Blood Bank & Transfusion Service of the University of Michigan (attribution used with permission), the FDA issued a Draft Guidance for Industry "Computer Crossmatch" (Electronic Based Testing for the Compatibility between the Donor’s Cell Type and the Recipient’s Serum or Plasma Type) June 2007.
   
   In Suzanne's experience, the early adopters of the electronic crossmatch did not have software available to determine if a patient was eligible for the electronic crossmatch. However, as long as the facility had validated their process (the process is more than just the computer system, but all the steps in the "process" including determining patient eligibility and the process meets the requirements of the FDA guidance and AABB Standards), there should have been no regulatory or accrediiation issues. The University of Michigan has been performing the electronic crossmatch since 1992 on software that does not do many of the checks that were cited in the letter to the editor that Professor John Judd and Ms. Butch wrote; see "Requirements for the computer crossmatch" (Transfusion 34:187;1994). Software vendors have since adopted this requirements. However, saying "be careful what you ask for" applies here. In the case of massive transfusion in patients with multiple antibodies, she believes that it makes no sense to do a serologic crossmatch with units that have been untested for the antigens to which the patient has antibodies using a patient specimen that is diluted. Note that the original specimen is depleted during the crossmatching process and a new specimen needs to be typed and screened and then crossmatches need to be completed. All of this takes time and provides no additional benefit to the patient while increasing staff stress. According to Ms. Butch, it is now time to consider a modification of the requirements to fit current day needs.

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