Editing Blood transfusion (section)

=== Unknown blood type ===
Because [[blood type]] O negative is compatible with anyone, it is often overused and in short supply.<ref name="AABBfive-5">{{Citation |author1 = American Association of Blood Banks |author1-link = American Association of Blood Banks |date = 24 April 2014 |title = Five Things Physicians and Patients Should Question |publisher = American Association of Blood Banks |work = [[Choosing Wisely]]: an initiative of the [[ABIM Foundation]] |url = http://www.choosingwisely.org/doctor-patient-lists/american-association-of-blood-banks/ |access-date = 25 July 2014 |archive-url = https://web.archive.org/web/20140924075027/http://www.choosingwisely.org/doctor-patient-lists/american-association-of-blood-banks/ |archive-date = 24 September 2014 |url-status = dead }}, which cites
* {{cite web|author1=The Chief Medical Officer's National Blood Transfusion Committee|title=The appropriate use of group O RhD negative red cells|url=http://hospital.blood.co.uk/library/pdf/nbtc_bbt_o_neg_red_cells_recs_09_04.pdf |archive-url=https://ghostarchive.org/archive/20221009/http://hospital.blood.co.uk/library/pdf/nbtc_bbt_o_neg_red_cells_recs_09_04.pdf |archive-date=2022-10-09 |url-status=live|publisher=[[National Health Service]]|access-date=25 July 2014|year=c. 2008}}</ref> According to the  [[AABB|Association for the Advancement of Blood and Biotherapies]], the use of this blood should be restricted to persons with O negative blood, as nothing else is compatible with them, and women who might be pregnant and for whom it would be impossible to do blood group testing before giving them emergency treatment.<ref name="AABBfive-5" /> Whenever possible, the AABB recommends that O negative blood be conserved by using blood type testing to identify a less scarce alternative.<ref name="AABBfive-5" />