Autologous blood transfusion (ABT) is a technique that involves the collection of filtered blood from a patient's wound drain, inserted during surgery, and its subsequent re-infusion to that individual.
ABT may be an appropriate and safer option to allogenic blood transfusion (see box). Contraindications to ABT include bacterial infection of the wound, malignancy or sickle cell disease.
The benefits of ABT are well-established for knee arthropathy and its use is endorsed by the British Orthopaedic Association in its 2005 guidance 'Blood conservation in elective orthopaedic surgery'.
The procedure is performed after the application of a thigh tourniquet, which results in virtually no loss of blood during surgery.
The subsequent loss into the wound drains is available for re-infusion for up to 12 hours with some systems.
The adoption of this policy has decreased the donor bank blood being cross-matched and administered, especially in orthopaedics, mainly in knee arthroplasty. An audit was undertaken in Bristol to assess whether similar benefits might be achievable in patients undergoing hip arthroplasty.
The audit assessed 50 patients who were informed about the background of the study when attending the pre-admission assessment clinic and were given a guide on blood transfusion options.
The anaesthetic and surgical technique used was directed at minimising peri-operative blood loss to about 300ml. The ABT regimen used identical post-operative ABT systems and the established re-infusion policy for knee arthroplasty. This system allows the collection of up to 1,200ml of blood throughout the first 12 post-operative hours.
Only three of the 50 consecutively assessed patients required bank blood, none more than two units.
In 15 per cent of patients, most drainage occurred more than four hours after the end of surgery, possibly associated with greater patient movement coinciding with the return of motor function. The re-infusion of this blood is possible with a system that allows safe collection for an extended period of time.
Safety of ABT
The audit confirmed the safety and logic of extending the use of ABT for hip arthroplasty and resulted in a change in policy regarding the need for routinely cross-matching two units of blood for all patients.
Charges for making bank blood available vary between hospitals, but it is not unusual for each transfused unit to cost £150.
Those cross-matched and made available, but not given, can cost about £80. There are usually some cost implications that are unrecognised.
It should be possible for GPs to reassure their patients contemplating knee or hip arthroplasty that safer options exist should there be a need for blood transfusion.
- Dr Coates is consultant anaesthetist at the Bristol Nuffield Hospital at St Mary's, Bristol
- Guidelines on autologous blood transfusion on perioperative haemodilution and cell salvage. British Committee for Standards in Haematology, Blood Transfusion Task Force. Br J Anaesth 1997; 78: 768-71.
- www.boa.ac.uk (British Orthopaedic Association)
THE ABT SAFER OPTIONS
Safety: the potential complications of adverse immunological reaction or infection associated with the administration of 'bank' blood (homologous or allogenic transfusion) should be avoided.
Availability: the availability of bank blood has decreased since the introduction of stricter criteria relating to donor suitability. For example, prospective donors must not have received a transfusion themselves after 1980.
Flexibility: greater reliance on ABT allows more major, elective surgery to be scheduled without the need for cross-matched bank blood to be immediately available.
Economy: the use of ABT in preference to bank blood may be a cost-effective alternative.
Responsibility: both patient and clinician will appreciate the reduction of risk and expense. The amount of bank blood available for emergency cases should be increased.