Why should blood be kept covered during transfusion?

Why Blood Should Be Kept Covered During Transfusion

Blood components must be kept covered during transfusion to prevent bacterial contamination, reduce the risk of transfusion reactions, and maintain product integrity, which directly impacts patient morbidity and mortality.

Rationale for Covering Blood During Transfusion

1. Prevention of Bacterial Contamination

• Bacterial contamination of blood products represents one of the most significant infectious risks in transfusion medicine 1
• Contamination rates are estimated at approximately 1 in 750 to 1 in 1000 platelet components 2
• Covering blood units helps maintain sterility of the external surface of the blood bag, reducing the risk of introducing contaminants during handling

2. Maintaining Product Integrity

• Blood components must be transported and administered in appropriate conditions to maintain their integrity 3
• Exposure to environmental factors can compromise blood component quality:
  • Light exposure can degrade certain blood components
  • Temperature fluctuations affect cellular viability
  • Environmental contaminants can compromise sterility

3. Preventing Transfusion Reactions

• Transfusion reactions are a significant cause of morbidity and mortality
• Transfusion-associated circulatory overload (TACO) is now the most common cause of transfusion-related mortality 3
• Febrile, allergic, and hypotensive reactions can occur within 24 hours following transfusion 3
• Maintaining proper handling procedures, including covering blood units, is part of the comprehensive approach to minimizing these risks

Clinical Protocol for Blood Transfusion

Pre-Transfusion Preparation

1. Verify that blood components are properly covered during transport from blood bank
2. Ensure blood components are transported in appropriate storage containers that maintain integrity 3
3. Check visually for any leakage, discoloration, or presence of clots/clumps before administration 3

During Transfusion

1. Keep blood unit covered throughout the transfusion process
2. Use only approved blood administration sets with appropriate filters (170-200 μm) 3
3. Complete red cell transfusions within 4 hours of removal from controlled storage 3
4. Monitor patient for signs of transfusion reactions (tachycardia, rash, breathlessness, hypotension, fever) 3

Special Considerations

• Use appropriate blood warming devices when indicated, never improvised warming methods 3
• For rapid transfusion, use only approved pressure devices and warming equipment 3
• When transferring patients during ongoing transfusion, ensure blood components remain covered and properly stored 3

Common Pitfalls to Avoid

1. Improper warming: Never warm blood using improvised methods such as warm water, microwaves, or radiators 3
2. Extended exposure: Avoid leaving blood units uncovered and exposed to environmental conditions
3. Delayed recognition of reactions: Failure to monitor for and promptly identify transfusion reactions increases mortality risk 3
4. Inadequate documentation: Ensure 100% traceability of all blood components as legally required 3

By maintaining proper coverage of blood products during transfusion, healthcare providers can significantly reduce the risks of bacterial contamination, product degradation, and adverse transfusion reactions, ultimately improving patient outcomes and reducing transfusion-associated morbidity and mortality.