Requiring > 40 mL/kg (40% blood volume) or 4 u for adult / patient > 30 kg over 2 hours or less
Requiring or likely to require complete blood volume replacement or 10 u for adult in 24 hours
Newborn – 1 month 90 mL/kg
1-12 months 85 mL/kg
1-14 years 80 mL/kg
> 14 years 75 mL/kg
Obese children 65 mL/kg
Massive transfusion 
Exchange transfusion
Transfusion-associated circulatory overload
Platelet transfusion
Blood products
Extracorporeal membrane oxygenation
Fresh frozen plasma
Cryoprecipitate transfusion