Doctors have called for an urgent review of transfusion policies after a UK-wide study of 221 hospitals found that patients admitted with acute upper gastrointestinal bleeding (AUGIB) are more than twice as likely to suffer further bleeding if they receive a red blood cell transfusion within 12 hours. The study also found that death rates were more than a quarter higher in patients who had received transfusions within that timescale. AUGIB accounts for 14 per cent of red blood cell units transfused in the UK.