RESUMO
BACKGROUND: Preoperative testing in patients scheduled to undergo surgery often includes determining the ABO group and Rh type and screening for atypical alloantibodies in blood samples. AABB recommends obtaining blood samples within 3 days of transfusion. This was extended to 30 days to minimize the number of phlebotomies, avoid delays in providing blood during surgery, and decrease the laboratory workload. This study was conducted to show that extending the expiration date of the preoperative blood sample for blood typing and screening to 30 days will serve our purpose and provide better patient care. STUDY DESIGN AND METHODS: Data were collected for all patients undergoing elective surgery with perioperative blood samples submitted to our blood bank over 31 months. Each patient completed a questionnaire to determine whether his or her samples qualified for a 30-day preoperative clot. The questionnaires were validated upon preoperative screening. A transfusion medicine physician made the final determination regarding whether the samples qualified for 30-day typing and screening. These blood samples were used for cross-matching to find compatible blood during surgery. RESULTS: A total of 12,310 preoperative blood samples were received with a request for typing and screening, 4,370 (35.5%) of which qualified for a 30-day expiration date. No significant problems were encountered with these blood samples. CONCLUSION: Extension of the preoperative clot expiration date from 3 to 30 days has improved service to our patients and their physicians and indirectly reduced the laboratory workload.