From the Guidelines
Warming blood transfusion products to body temperature does not significantly increase the recipient's core body temperature, but rather helps prevent hypothermia, especially in vulnerable populations or during massive transfusions. The primary goal of warming blood products is to prevent hypothermia, which can occur when cold blood is rapidly infused into a patient, particularly during massive transfusions or in populations such as infants, trauma patients, or those undergoing lengthy surgeries 1. Key considerations for warming blood products include:
- Using approved, specifically designed blood warming equipment with a visible thermometer and audible warning to prevent overheating, which can cause hemolysis and protein denaturation 1
- Avoiding improvisations, such as putting the pack in warm water, in a microwave, or on a radiator, as these methods can damage blood components or cause overheating 1
- Monitoring settings regularly throughout the transfusion to ensure the blood products are warmed to the appropriate temperature, approximately 37°C 1
- Giving special consideration to vulnerable populations, such as neonates, children, elderly patients, and patients susceptible to cardiac dysfunction, when rapidly transfusing large volumes 1. In most clinical situations, allowing blood to rise to ambient temperature before transfusion is sufficient, but controlled warming of red cells, which are stored at 4°C, provides the greatest benefit in preventing hypothermia 1.
From the Research
Warming Blood Transfusion Products
- Warming blood transfusion products is essential to prevent hypothermia, which can be a serious clinical problem associated with massive transfusions 2.
- The optimal design of blood-warming devices should include a low priming volume, large heat transfer area, low pressure drop, and the ability to operate at high flow rates 2.
- Studies have shown that warming blood products to temperatures at or less than 43°C is safe and causes hemolysis only in clinically negligible proportions 3.
- Microwave energy has been investigated as a means of rapid in-line blood warming, with preliminary studies showing no significant hemolysis or damage to blood components 4.
Effect on Core Body Temperature
- A study on the effect of prehospital blood transfusion on patient body temperature found that warming blood products using a portable fluid-warming system prevented hypothermia and maintained body temperature homeostasis 5.
- Another study on warming blood products for transfusion to neonates found that an inline blood warmer can deliver blood products at near-physiologic temperatures with no detected damage 6.
- The use of blood warmers has been shown to be effective in preventing hypothermia and maintaining core body temperature, with no significant change in body temperature observed in patients receiving warmed blood products 5.
Key Findings
- Warming blood transfusion products is crucial to prevent hypothermia and maintain core body temperature 2, 5.
- The optimal temperature for warming blood products is at or less than 43°C, with no significant hemolysis or damage to blood components observed at this temperature 3.
- Portable fluid-warming systems and inline blood warmers are effective in delivering blood products at near-physiologic temperatures, with no detected damage to blood components 5, 6.