Use of group O RhD negative red cells

Only 6.5% of the Australian population is O RhD negative, however the demand for O RhD negative red cells has represented as high as 17% of Lifeblood’s total red cell issues. 

This means that the number of O RhD negative donors needs to be disproportionately higher than donors of other ABO blood groups, and their donation frequency also higher, to keep up with the demand.

The National Blood Authority (NBA) has published a range of resources to guide hospitals with their inventory management and emergency use of O RhD negative red cells along with a National statement for the emergency use of group O red blood cells.

General principles

1. Transfuse the same ABO and RhD group as the patient wherever possible.

2. Practice good inventory management by:

• Ensuring appropriate stock levels of O RhD negative red cells to minimise preventable wastage from unnecessary expiry.
• Avoiding transfusion of O RhD negative red cells to non-group O recipients to simply prevent soon to expire units being wasted.

3. Maintain adequate stocks of other ABO groups to avoid the unnecessary use of O RhD negative for patients with other ABO groups.

4. Consider rotating close to expiry O RhD negative stock to another laboratory in your network.

Indications for the use of Group O RhD negative red cells

• O RhD negative patients with anti-D.
• O RhD negative females with childbearing potential (≤ 50 years)
• O RhD negative paediatric males (≤ 18 years or as per local paediatric policy)
• Emergency, life-saving transfusions where the patient’s blood group (ABO/RhD) is unknown:
  • Females with childbearing potential (≤ 50 years).
  • Paediatric males (≤ 18 years or as per local paediatric policy).
  • Patients where gender and age are uncertain.
• Neonatal transfusion where suitable group specific red cells are unavailable. 
• When phenotyped red cells are O RhD negative.

In emergency situations where O RhD negative red cells are being used while the patient's blood group is being established (where this is institutional policy): 

• Obtain a pretransfusion specimen as soon as possible, and before blood components are administered, to allow urgent blood grouping (ABO/RhD) to minimise the ongoing need for uncrossmatched O RhD negative red cells. 
• Switch to transfusion of group specific or group compatible red cells once the patient has a confirmed blood group. 

Use of Group O RhD positive for Group O RhD negative patients

• Organisations should develop a local policy for the use of O RhD positive red cells in emergency situations and where stocks of O RhD negative red cells are limited. 
• For females > 50 years and adult males > 18 years:
  • In emergency transfusions where the  patient’s blood group (ABO/RhD) is unknown, issue O RhD positive uncrossmatched red cells until the blood group has been determined using a valid current specimen. 
  • For larger volume blood replacement (e.g. more than 4 units of red cells) consider using O RhD positive red cells if the patient does not have an existing or historical anti D.
  • If O RhD negative blood is unavailable or in extremely short supply, consider using O RhD positive red cells provided no anti-D is detected on pretransfusion testing.
• Once four units of O RhD negative red cells have been provided for a patient with unknown RhD type, consider use of O RhD positive red cells irrespective of the patient’s age, gender, or child bearing potential (as per local policies). 
• For RhD negative patients who have received O RhD positive red cells in a critical bleeding situation, use of RhD positive red cells may continue until that critical bleeding episode has resolved.
• For RhD negative females of childbearing potential who have received RhD positive red cells, there is the risk of RhD alloimmunisation and possible impact on future pregnancies. This should be discussed with the patient/carer of this event along with the need for any additional monitoring. RhD immunoglobulin (RhD-Ig) prophylaxis maybe applicable and a haematologist consultation may be appropriate.