A 72-year-old man presents with melaena and dizziness. He has a history of coronary artery disease and is taking acetylsalicylic acid. On arrival, blood pressure is 98/60 mm Hg and heart rate 110 beats per minute. Hb is 74 g per litre. After initial resuscitation with intravenous crystalloids and blood typing, what is the most appropriate transfusion strategy?