What are the latest guidelines for rapid blood infusion and when is a blood warmer used?

Guidelines for Rapid Blood Infusion and Blood Warmer Use

Blood warmers should be used in all adults undergoing surgery under general or regional anesthesia when infusing 500 ml or more of intravenous fluids and blood components, and are essential when rapidly transfusing large volumes to prevent hypothermia-related complications. 1

Rapid Blood Infusion Devices

Rapid blood infusion is necessary in cases of massive hemorrhage where large volumes of blood need to be administered quickly. The guidelines recommend several approaches:

Types of Infusion Devices

• Gravity or electronic infusion devices: Can be used for standard administration of blood components 1
• Rapid infusion devices: Specifically designed for massive hemorrhage scenarios with infusion rates of 6-30 L/h, typically incorporating blood-warming capability 1
• External pressure devices: Allow administration of a unit of red cells within minutes, but should only be used in emergency situations with large-gauge venous access 1

Requirements for Infusion Devices

• Must be CE-marked and verified by the manufacturer as safe for blood transfusion 1
• Should use compatible blood component administration sets with integral mesh filters (170-200 μm) 1
• Volume delivered should be monitored regularly throughout infusion 1
• Device settings should be checked during pre-administration procedures 1

Blood Warmer Use Guidelines

When to Use Blood Warmers

1. Mandatory use:

   • All adults undergoing elective or emergency surgery under general or regional anesthesia when infusing ≥500 ml of fluids or blood components 1
   • When flow rate exceeds 50 ml/kg/h in adults 1
   • During massive transfusion scenarios 1

2. Special consideration required:

   • When rapidly transfusing large volumes to:
     • Neonates
     • Children
     • Elderly patients
     • Patients with cardiac dysfunction 1

3. Not routinely needed:

   • In most other clinical situations, allowing blood to rise to ambient temperature before transfusion is sufficient 1

Blood Warmer Requirements

• Must be specifically designed and approved for blood warming 1
• Should have a visible thermometer and audible warning system 1
• Must be regularly maintained 1
• Should warm blood components to 37°C 1
• Settings should be monitored regularly throughout transfusion 1

Critical Warning

• Never warm blood using improvisations such as warm water baths, microwaves, or radiators 1

Clinical Importance of Blood Warming

Prevention of Complications

• Hypothermia during massive transfusion increases risk of:
  • Disseminated intravascular coagulation (DIC)
  • Organ failure
  • Increased mortality 1
  • Coagulopathy 2

Effectiveness of Warming Systems

• The Rapid Infusion System (RIS) has been shown to maintain core body temperature at approximately 35.85°C even during massive transfusions averaging 6.4 times the circulating blood volume 2
• At higher pressure rates (300 mmHg), blood warmers may not fully prevent hypothermia risk, with outlet temperatures reaching only 33.7°C versus 37.1°C at 150 mmHg 3

Implementation in Massive Transfusion Protocols

• Blood warmers should be available in all emergency rooms and operating theaters 1
• A designated coordinator should take responsibility for communication and documentation during massive transfusion events 1
• Hypothermia prevention should include:
  • Prewarming resuscitation fluids
  • Patient warming devices (e.g., warm air blankets)
  • Temperature-controlled blood warmers 1

Potential Concerns with Blood Warming

• Recent research indicates that rapid infusion through devices like the Belmont infuser may decrease platelet counts and function while not affecting red cell counts 4
• The combination of blood warmers and compression sleeves at 150-300 mmHg does not appear to generate significant hemolysis 3

Remember that maintaining normothermia during massive transfusion is critical for reducing mortality and preventing coagulopathy. Always use properly designed and maintained blood warming equipment when rapidly infusing large volumes of blood products.