Do stoppers or stopper byproducts cause crossmatch interferences?
A. The American Association of Blood Banks standards (20th edition) mandate the minimum storage retention for recipients’ samples. The recipient’s blood specimen and a sample of the donor’s red cells must be sealed or stoppered and kept at refrigerator temperature for at least seven days after each transfusion.1 The proposed 21st edition (5.11.6.2 Recipient samples shall be stored at refrigerated temperatures for at least seven days after transfusion) has similar wording. Maintaining the patient’s and donor’s samples allows for repeat or additional testing if there is any adverse effect to the transfusion. Individual institutions need to specify other sample storage conditions such as temperature range, storage position, or maximum storage duration that maintains sample stability. How long samples can be stored depends most often on the available refrigerator space. Although some transfusion service blood banks store patients’ samples at 1°-6°C in the same continuously monitored refrig
