[Type and Screen: immunohematological safety is ensured and costs are lowered].

UNLABELLED

TYPE AND SCREEN: (T + S) means: no routine cross match before transfusion. ABO- and Rh-(Blgr) blood groups (type) are done and irregular allo-antibodies are sought (screen). If screen is negative, instant saline test (IST) or Blgr control, and if screen is positive, conventional cross match is done.

GOALS

Are all clinically relevant antibodies discovered with T + S? Are laboratory costs lower?

METHODS AND STUDY DESIGN

Prospective study over more than 3 years. Blgr and cross match were done in tubes and AB screen and antibody identification (panel) were sought using the gel-test (DiaMed) with bromelin (enz) and LISS antiglobulin test (IAT). Underlying all testing were the directives of the Swiss blood donation services.

RESULTS

Enzyme-only positive antibodies are not relevant for blood transfusion, as shown by our data from more than 10000 comparisons of enz- and IAT-screens. 32 patients with positive enz-antibodies and negative cross match were transfused without problems. The enz-screen was abandoned for more than 12 months' follow-up in more than 20000 transfused patients. Before using the T + S, one unit of transfused RBC needed (on average) 3.7 cross matches, and after introduction of T + S only 0.3. Although the number of T + S increased significantly, we effectively saved some CHF 280000 per year.