Routine cross-matching is not necessary for a transurethral resection of the prostate.

Two hundred and fifty-five consecutive patients undergoing transurethral prostatectomy were studied prospectively to test a policy of not routinely cross-matching blood. Blood was ordered only for patients with anaemia, a major medical risk factor, a prostate gland estimated to be greater than 60 g, or the presence of red cell alloantibodies. Of the 203 patients who were "grouped and saved" only, 30 (12%) were subsequently cross-matched and 22 (8.5%) transfused. There were no significant problems as a result of the operation of this policy. The value of these pre-operative criteria for cross-matching was confirmed, apart from the clinical estimation of prostatic size. The use of such a policy could be of significant value to the hospital blood transfusion services.