Transfusion medicine handbook

3. Guide to Good Transfusion Practice

3.16 Warming of Blood Components

If warming is clinically indicated, use only an appropriate and approved system. The warming system must be equipped with a visible thermometer and an audible alarm as malfunction can result in red cell haemolysis. Blood components must not be warmed above 41°C.

Clinical indications for the use of blood warmers:

• Large volumes transfused rapidly, for example > 50 mL/kg/hr in adults and > 15 mL/kg/hr in children.
• Neonatal exchange transfusions.
• Trauma situations in which core-rewarming measures are indicated.
• Patient rewarming phase during cardiopulmonary bypass surgical procedures.
• Transfusions for patients with clinically significant cold reactive antibodies (‘cold agglutinins’), i.e., symptomatic cold haemagglutinin disease (CHAD).

Blood warmers are not indicated for routine transfusion of blood. Blood warming is seldom necessary or desirable for elective transfusion at conventional rates, even for patients with asymptomatic cold agglutinins.