The 'transfusion trigger' in three large West of Scotland hospitals: medical staff questionnaire survey.

Efficient use of blood is desirable due to increased demand for blood, shortfall in donations, and the risk of mismatch transfusion accidents and transfusion-transmitted infections. We surveyed transfusion practice in three hospitals. Low haemoglobin was a feature in 91% of transfusion requests and is the commonest 'trigger' for transfusion. Forty-eight per cent of transfusions were initiated with the aim of restoring haemoglobin to 10 g dL(-1). Seventy-three per cent of transfusions were given when the patient's haemoglobin was between 7 and 10 g dL(-1). These figures suggest liberal blood use when compared with international practice. Major healthcare resource and patient safety implications result from this. Evidence-based guidelines issued at both local and national levels would be helpful.