Transfusion Alternatives Pre-operatively in Sickle Cell Disease (TAPS)

Inclusion Criteria: * Sickle cell disease, either Hb SS or Hb SB0 thal, confirmed by Hb electrophoresis, Deoxyribonucleic Acid (DNA) analysis or High Performance Liquid Chromatography (HPLC) * At least 24 hourse and no more than 14 days before surgery and a date for surgery has been given * Surgery to be low or medium risk * Surgery to be with general or regional anaesthesia * Written informed consent from patient/parent/guardian is given * More than six months since previous TAPS trial surgery. Exclusion Criteria: * Having a procedure involving intravascular contrast radiography or an imaging procedure * On a regular blood transfusion regime * Had a blood transfusion within the last three months * The planned procedure involves local anaesthetic only * Haemoglobin level at randomisation less than 6.5g/dL * Children with a clinical history of stroke (history of silent infarcts would not preclude randomisation) * Acute chest syndrome within the last six months, or patient has ever required intubation and mechanical ventilation for treatment of acute chest syndrome * Oxygen saturation at randomisation less than 90% * Patient is on renal dialysis * Already entered twice into the TAPS trial * The physician is unwilling to randomise the patient (such patients will be entered into a trial log).