Immediate prediction of blood requirements in trauma victims.

Current recommendations for the management of trauma victims include immediate crossmatching of 4 to 6 units of blood. Unused crossmatched blood is withdrawn from the available blood pool for 48 hours and costs the patient $33 per unit. Growing blood shortages and increasing laboratory costs demand reexamination of this practice. The purpose of this study was to examine blood usage in trauma victims and to develop new guidelines for emergency room requests for blood. The following clinical variables were reviewed in 250 trauma victims to determine their value as predictors of blood usage: age, sex, mechanism of injury, initial vital signs, trauma score (TS), and injury severity score (ISS). The best predictor of blood use was the trauma score. Of the total group, 71% had a TS greater than 14; 91% of these patients did not require transfusion. Twenty-eight percent of the total group had a TS equal to or less than 14; 70% of these patients did require transfusion. The data strongly suggest that type and screen can safely replace type and crossmatch as the initial blood bank requests in patients with trauma scores greater than 14. Blood requirements in patients with a trauma score less than or equal to 14 continue to warrant immediate crossmatching.