Chapter 10



  • The most common causes of anaemia in children are nutritional and infectious. Treatment of the underlying cause is the primary consideration.
  • If hypoxia occurs despite the normal compensatory responses to anaemia, immediate supportive care is required. If the child continues to be clinically unstable, a transfusion may be indicated.
  • The decision to transfuse should not be based on the haemoglobin level alone, but also on a careful assessment of the child’s clinical condition.
  • Hb < 4 g/dL is an indication for transfusion.
  • Hb 4-6 g/dL is an indication for transfusion if the patient is hypoxic, acidotic, impaired consciousness or has high parasitaemia.
  • In some conditions, such as haemoglobinopathies (sickle cell disease and thalassaemia) repeated red cell transfusions may be indicated.
Refer to the national paediatric guidelines.


Neonates and children are not just small adults, they are different in their metabolic and physiologic behaviour. Therefore pathophysiology in paediatrics and neonatology is different from what can be observed in adolescents and adults.

A number of key principles that apply:

  • The prevention and early treatment of anaemia is a vital part of the strategy to reduce the need for paediatric transfusion.
  • If hypoxia occurs despite the normal compensatory responses to anaemia, immediate supportive care is required. If the child continues to be clinically unstable, a transfusion may be indicated.
  • The decision to transfuse should not be based on the haemoglobin level alone, but also on a careful assessment of the child’s clinical condition.
  • In patients at risk of circulatory overload, transfusion of red cells is preferable to whole blood. Paediatric blood packs (70–100 mL) should be used, if available, to decrease exposure to multiple donors.
  • In some conditions, such as haemoglobin-opathies (sickle cell disease and thalassaemia) repeated red cell transfusions may be indicated.
  • There are very few indications for transfusing fresh frozen plasma.
  • Inappropriate and ineffective use can pose both transmissible (e.g. HIV and hepatitis) and non-transmissible risk and should be avoided.


10.2.1 Decreased production of normal red blood cells

  • Nutritional deficiencies due to insufficient intake or absorption (iron, B12, folate).
  • HIV infection.
  • Chronic disease or inflammation.
  • Lead poisoning.
  • Chronic renal disease.
  • Neoplastic diseases (leukaemia, neoplasms invading bone marrow).
  • Congenital or acquired aplasia or hypoplasia.

10.2.2 Increased destruction of red blood cells

  • Malaria.
  • Haemoglobinopathies (sickle cell disease, thalassaemia).
  • G6PD deficiency.
  • RhD or ABO incompatibility in the newborn.
  • Autoimmune disorders.
  • Spherocytosis.

10.2.3 Loss of red blood cells

  • Hookworm infection.
  • Acute trauma.
  • Surgery.
  • Repeated diagnostic blood sampling.


  • Haemoglobin concentration of < 4 g/dL , irrespective of the clinical condition of the patient, is an absolute indication for erythrocyte transfusion.
  • Haemoglobin concentration of 4–6 g/dL , is an absolute indication for erythrocyte transfusion if any the following clinical features are present:
    - Clinical features of hypoxia:
    - Acidosis (usually causes dyspnoea).
    - Impaired consciousness.
    - Hyperparasitaemia (> 20%).
  • Haemoglobin > 6 g/dL is the same as adult indications.


Never re-use an adult unit of blood for a second paediatric patient because of the risk of bacteria entering the pack during the first transfusion and proliferating while the blood is out of the refrigerator.

Where possible, use paediatric blood packs which have been produced in a closed sterile system. These allow repeat transfusions to the same patient from a single donation unit.

Infants and children require small volumes of fluid and can easily suffer circulatory overload if the infusion is not well controlled. If possible, use an infusion device that makes it easy to control the rate and volume of infusion.


If transfusion is needed, give sufficient blood to make the child clinically stable.

5 mL/kg erythrocytes or 10 mL/kg whole blood are usually sufficient to relieve acute shortage of oxygen-carrying capacity. This will increase haemoglobin concentration by approximately 2–3 g/dL unless there is continued bleeding or haemolysis.

An erythrocyte transfusion is preferable to whole blood for a patient at risk of circulatory overload, which may precipitate or worsen cardiac failure. 5 mL/kg of red cells gives the same oxygen-carrying capacity as 10 mL/kg of whole blood and contains less fluid volume to overload the circulation.

Where possible, use a paediatric blood pack and a device to control the rate and volume of transfusion and although rapid fluid infusion increases the risk of volume overload and cardiac failure, give the first 5 mL/kg to relieve the acute signs of tissue hypoxia. Subsequent transfusion may be given slower e.g. 5 mL/kg of red cells over 1–2 hours. Aim to give all transfusion over < 2 hours. Any transfusion needs to be completed in < 4 hours. The clinical state of the patient will determine the maximum tolerated rate.

A syringe driver can be used to administer a small volume to a neonate or infant. IV lines and syringes used for transfusing blood components should:
  • incorporate an in-line filter [170-200 micron];
  • be single use only and discarded appropriately;
  • have Leur-lock connections;
  • have a label attached showing date and time of preparation and expiry date and time; and
  • identical donor and patient information as the original pack from which the component was drawn.

Give frusemide 1 mg/kg by mouth or 0.5 mg/kg by slow IV injection to a maximum dose of 20 mg if patient is likely to develop cardiac failure or pulmonary oedema. Do not inject it into the blood pack.

Monitor during transfusion for signs of an adverse event in the same manner as adult patients.

Re-evaluate the patient’s clinical condition after transfusion. A repeat haemoglobin or haematocrit may also be beneficial. If the patient is still anaemic with clinical signs of hypoxia or a critically low haemoglobin level, give a second transfusion of 5–10 mL/kg of red cells or 10–20 mL/kg of whole blood. Continue treatment of anaemia to help haematological recovery.


10.6.1 Selection of components

See table 10.1.

10.6.2 Specific clinical situations (neonatal) Exchange transfusion

The main indication for neonatal exchange transfusion is to prevent neurological complications (kernicterus) caused by a rapidly-rising unconjugated bilirubin concentration. This occurs because the immature liver cannot metabolise the breakdown products of haemoglobin. The underlying cause is usually haemolysis (red cell destruction) due to antibodies to the baby’s red blood cells and is called Haemolytic Disease of the Newborn (HDN).

If exchange transfusion is needed:

  • Use a group O blood unit that does not carry the antigen against which the maternal antibody is directed:
    - For HDN due to anti-D: use group O RhD negative.
    - For HDN due to anti-Rh c: use group O RhD positive that does not have the c antigen (e.g. R1R1, CDe/CDe).
  • An exchange transfusion of about two times the neonate’s blood volume (about 170 mL/kg) is most effective to reduce bilirubin and restore the haemoglobin level; this can usually be carried out with one unit of whole blood.
  • A unit of whole donor blood will normally have a haematocrit of 37–45%, which is adequate for neonatal needs. There is no need to adjust the haematocrit of the unit, raising the unit Hct to 
  • 50–60% may risk polycythaemia.

Table 10.1 Selection of components

Product Indication Special requirements

Whole blood

Exchange transfusions for HDN

Freshest blood available (less than 5 days after collection), free of relevant allo-antibodies


“Top up” transfusion to raise Hb in symptomatic chronic anaemia. This is most commonly due to frequent blood sampling in premature infants

Small dose unit (paediatric pack from a single donation) to minimise exposure to different donors Sampling in critically ill neonates

Record the volume of each blood sample taken. If 10% of the blood volume is removed over 24–48 hours, check patient’s Hb level as a transfusion may be indicated. Convalescent and low birth weight babies
  • Measure the haemoglobin at weekly intervals. The haemoglobin level will drop 1 g/dL per week on average.
  • Do not transfuse on the basis of the haemo-globin level alone. Haemoglobin levels of 7 g/dL or less require investigation, but transfusion may not be required.
  • A reticulocyte count will assist in determining the need for transfusion.
  • Iron, folate and vitamin E may minimise the need for transfusion.
  • Consider transfusing an infant if anaemia is thought to be the cause of: 
    - Poor weight gain.
    - Fatigue while feeding.
    - Tachypnoea and tachycardia.
    - Other signs of decompensation.

10.6.3 Minimising the risks and increasing the effective use of neonatal transfusion

The following practical measures reduce the risks of neonatal transfusion and increase its effectiveness:

  • For an infant who is likely to need several ‘top-up’ transfusions over a period of days or weeks, use red cells in additive solution prepared in paediatric packs from a single unit of blood.
  • Reduce blood loss from diagnostic sampling:
    - avoid unnecessary repeat compatibility testing,
    - avoid non-essential laboratory tests, and
    - where possible, the laboratory should use micro-methods and should select suitable small sample tubes.
  • Avoid transfusing blood donated by blood relatives as the risk of graft versus host disease is increased.

10.6.4 Fresh frozen plasma

Fresh frozen plasma should only be used for specific clinical indications for which it is proved to be effective:

  • The correction of clinically important bleeding tendencies due to deficiency of plasma clotting factors.
  • For infusion or exchange transfusion treatment of the rare conditions of thrombotic thrombocytopenic purpura (TTP) or haemolytic uraemic syndrome (HUS).
Download This Chapter