Every patient receiving a fresh blood product needs a valid pretransfusion compatibility testing/blood group and antibody screen performed at the Royal Children's Hospital  (RCH) prior to blood transfusion.

Pretransfusion testing

All specimen collection and labeling must be done in accordance with The RCH specimen collection procedure and   blood transfusion - fresh blood products procedure.

Pretransfusion compatibility testing prior to transfusion involves the following;

Blood group and antibody screen:

1. Determines the ABO and Rh(D) group of the recipient
2. Involves a red cell antibody screen to detect red cell antibodies
   1. For patients who have "no red cell antibodies detected", compatible units are selected and issued electronically
   2. For patients who have "red cell antibodies detected", further laboratory work is required to identify the specificity of the antibody, to type the patient and donor units in order to provide specific antigen negative blood and to perform a full serological crossmatch. For patients with multiple antibodies this work can take several hours to complete.
3. Correlating with previous transfusion and blood group records.
   The patient's current blood group must agree with any previous record of the patients group. Patient's who have previously had clinically significant red cell antibodies detected require antigen negative blood and full serological crossmatching.

If a patient is having a planned surgery where blood loss is expected, or they may require a planned RBC transfusion, an order for a blood group and antibody screen should be made. The date and type of surgery or expected date of transfusion can be outlined in the clinical notes field of the order. Blood bank will then be aware of the potential requirements for blood products and can make provisions as necessary. If you know your patient has special transfusion requirements, a conversation can still be had with the blood bank to discuss individual transfusion requirements.   

72 hour rule

A blood group and antibody screen expires 72 hours after collection.  A fresh blood group and antibody screen will be required for any units not commenced within the 72 hour period.  The time and date of collection of the cross match specimen is indicated in the Electronic Medical Record (EMR). If a unit of red cells is ordered in EMR without a current blood group and antibody screen, a prompt will appear with the option to order a blood group and antibody screen at the time of ordering the red cells. 

The 72 hour rule also applies whenever a patient has been transfused or is/has been pregnant within the last 3 months. This internationally accepted safeguard is used to prevent a transfusion reaction in patients who form antibodies to foreign red cell antigens in response to pregnancy or transfusion. 

The only exceptions to the 72 hour rule are some neonates and infants during the first four months of postnatal life (neonatal extended expiry) or those patients who have extended expiry crossmatching completed prior to having planned surgery (extended expiry)

Extended expiry

Extended expiry allows patients having a planned admission for spinal, craniofacial or cardiac surgery to have a blood group and antibody screen performed and remain valid for 30 days before their planned date of surgery.

For the the extended expiry blood group antibody screen to remain valid, certain conditions must be met prior to sampling and maintained throughout the 30 day period.

The following conditions must be met:

• No transfusions in the past three months
• No pregnancy in the past three months .
• The blood bank must receive a signed declaration from the parent/guardian/patient in order to validate the sample.
• No red cell antibodies detected 
• A negative DAT

If any of these conditions change in the lead up to surgery, the parents/guardians/patient will have instructions to contact the blood bank to inform them of these changes. Another blood test will be required to ensure to confirm the blood group and antibody screen.  

Forms are located here: 

1. English as a first language or primary language spoken at home
2. Interpreter service used.

Neonatal extended expiry

The neonatal extended expiry (ASBT protocol) prevents repeated blood group antibody screening prior to transfusion for infants during the first 4 months of life. This protocol recognises that the development of antibodies to red cell antigens is very uncommon in the first 4 months of life. The protocol reduces the requirement for repeated sampling of blood.

Which patients are eligible?

Any infant less than 4 months of age who is likely to require more than one transfusion.

The laboratory will make an assessment of suitability according to established criteria:

• Less than 4 months age
• Pretransfusion ABO and Rh(D) group performed
• DAT negative
• No atypical red cell antibodies detected
  

If accepted, the laboratory will issue a report indicating that a further sample will not be required for any further blood group and antibody screen samples until the baby is 4 months of age and will a specify this date. 

Who is excluded?

Any infants with a positive DAT and/or significant maternal red cell antibody shall be excluded.

How to request the neonatal extended expiry?

Order neonatal extended expiry in EMR.

Indicate any previous transfusion history, in particular intrauterine transfusion, or transfusion outside RCH. Indicate transferring hospital.

How to order blood for patients with an approved neonatal extended expiry order?

Once an infant is accepted on the neonatal extended expiry, further samples are not required for pretransfusion testing. Blood can be ordered as per regular ordering procedure in EMR.

Prepare and transfuse order (Prescription)

Refer to the EMR tip sheet for further information.

The ‘prepare’ and ‘transfuse’ orders are the responsibility of the medical practitioner. It is the authorisation for blood bank to prepare the blood product and for clinical staff to administer it.

In EMR, complete the ‘transfuse and prepare’ orders only if there is an intention to transfuse.

The ‘prepare’ order automatically prints in blood bank. It must include:

• Relevant clinical notes
• Type of blood product
• Dose
  • In a patient < 20kg, the order should be in mls
  • If patient >20kg, typically 1 unit and reassess
    • (Higher doses allowed in MTP/ red cell exchange/chronic transfusion programmes/cardiopulmonary bypass)
• Indication for transfusion
• Any special requirements
  • RBC (CMV negative/irradiated/other – please specify e.g. phenotype matched)
  • FFP ( Cryodepleted/IgA deficient)
  • Platelets (CMV negative/washed/HLA matched/Apheresis) 
• Clinical notes – can specify any special needs including the need for pre-medication
• Date and time transfusion required

The ‘transfuse’ order is electronically sent to ‘flowsheets’ and will include:

• Dose (mls/units) - populated from prepare order
• Transfusion duration 
• Confirmation of transfusion consent

The prescriber is responsible for ensuring:

• Transfusion is clinically appropriate and the indication is documented
• Expected benefits outweigh potential hazards
• Clinical staff have been informed of the prescription

Dosing recommendations:

Red blood cells:

Neonate: A typical dose for transfusion in neonates is 10 – 20 mL/kg  (where the upper end of the range applies to severe anaemia, expected ongoing risk factors or concurrent bleeding)

• Indications for neonatal red cell transfusion:
  • Bleeding (or the term used for the RBC transfusion) 

Patients < 20 kg: Volume to be transfused = 0.5 x patient weight (kg) x (desired Hb – patients current Hb). 

Patients > 20 kg: Volume to be transfused = 0.5 x patient weight (kg) x (desired Hb – patients current Hb) however no more than 1 unit should be transfused before re-testing the patient Hb to assess for rise.

Typical RBC units are 260 mL (+/-19 mL) volume. 

Indications for red blood cell transfusion:

• Hb <70g/L; a RBC transfusion is often indicated, however lower thresholds may be acceptable in patients without symptoms and where specific therapy (e.g. iron) is available
• Hb <70-90g/L; a RBC transfusion may be indicated, depending on the clinical setting e.g. presence of bleeding or haemolysis and clinical signs and symptoms of anaemia
• Hb >90g/L; RBC transfusion is often unnecessary and may be inappropriate
  

Transfusion may be indicated at higher thresholds for specific situations: 

• Preterm neonates; Hb thresholds vary depending on postnatal age and respiratory support (see above and neonatal transfusion recommendations at RCH) 
• Children with cyanotic congenital heart disease or extra-corporeal life support (ECLS) 
• Children with haemoglobinopathies (thalassaemia or sickle cell disease) or on a chronic transfusion programme. 

Platelets

For patients less than 15 kg the usual dose is 10 mL/kg. Patients over 15 kg can generally have one unit of platelets.

The usual dose in an adult is one unit, either pooled or apheresis.

ITP – immune thrombocytopenia, TTP – thrombotic thrombocytopenic purpura, MDS – myelodysplastic syndrome. 

Fresh Frozen Plasma (FFP) 

Indications for FFP transfusion

FFP is NOT indicated for the following:

• The correction of minor coagulation abnormalities (minor prolongation of the INR/APTT) in the non-bleeding child
• Liver disease when there are minor coagulation abnormalities and no-bleeding
• For reversal of a INR <2.0 in patients undergoing minor procedures

FFP transfusion volumes and rate

Formula for calculating transfusion volume: 10 - 20 mL/kg

Typical unit volume: ~284 mL. FFP pedipak ~69 mL

Transfusion rate: 10 - 20 mL/kg/hr

Cryoprecipitate

Cryoprecipitate is NOT indicated for the following:

• Non-bleeding children with mildly reduced fibrinogen levels
• Liver disease when there are minor coagulation abnormalities and no active bleeding

Cryoprecipitate transfusion volumes and rate

Formula for calculating transfusion volume: 5 - 10 mL/kg

Typical unit volume: ~36 mL

Transfusion rate: 10 - 20 mL/kg/hr

Consider a discussion with a haematologist if transfusing outside of the listed parameters.