Hi George, I would like to know what other labs use for the discard tube when collecting coag samples? CLSI recommends non-additive or another coag tube. Thanks for all you do.
Vicki Cardone, Hematology Supervisor
Children’s Hospital, Birmingham, AL
Hi, Vicki, nice to hear from you. Both BD and Greiner market plastic non-additive tubes; BD sells a red-closure tube and Greiner’s has a white closure. Standard red-closure plastic serum collection tubes, as well as serum separator tubes, contain negatively charged particulate activator that hastens clotting. The activator can theoretically carry over, thus should not be used ahead of a blue-closure tube. Make sure you are using a non-additive tube, not a standard red-closure tube as your discard tube. Glass red-stopper tubes still exist and have no additives, however most of us have adopted plastic for its relative safety.
An easier approach is to just use a blue-closure discard tube ahead of the specimen tube. This avoids the need to stock another tube and avoids the confusion over which discard tube to use. In this approach, cost could be an issue, however a discard tube is only needed when collecting blood using a butterfly set, as Dr. Emanuel Favaloro mentioned in a post last month. Geo.