How do I determine the appropriate volume of blood products to transfuse in a patient with major haemorrhage?

In hospital settings, use a ratio of 1 unit of plasma to 1 unit of red blood cells to replace fluid volume in adults with active bleeding ².

For children, base the volume on the child's weight, using a ratio of 1 part plasma to 1 part red blood cells ².

Hospital trusts should have specific major haemorrhage protocols to guide blood product transfusion volumes ².

Start with a fixed-ratio protocol for blood components and adjust based on laboratory coagulation results at the earliest opportunity ².