What are the guidelines for blood transfusion?

From the Guidelines

Blood transfusion guidelines recommend transfusing red blood cells when hemoglobin levels fall below 7.0 g/dL in adults in the absence of extenuating circumstances, such as myocardial ischemia, severe hypoxemia, or acute hemorrhage. This recommendation is based on the most recent and highest quality evidence available, as outlined in the 2017 guidelines for the management of sepsis and septic shock 1. The guidelines emphasize the importance of balancing the benefits of correcting anemia against the risks of transfusion reactions, infections, and volume overload.

Key Recommendations

• Transfuse red blood cells when hemoglobin levels fall below 7.0 g/dL in adults in the absence of extenuating circumstances 1
• Avoid the use of erythropoietin for treatment of anemia associated with sepsis 1
• Use fresh frozen plasma to correct clotting abnormalities only in the presence of bleeding or planned invasive procedures 1
• Prophylactic platelet transfusion is suggested when counts are < 10,000/mm3 (10 × 109/L) in the absence of apparent bleeding and when counts are < 20,000/mm3 (20 × 109/L) if the patient has a significant risk of bleeding 1

Rationale

The guidelines are based on a thorough review of the available evidence, including clinical trials and observational studies. The use of a restrictive transfusion strategy has been shown to decrease exposure to red blood cell transfusions by an average of approximately 40% 2. This approach can help minimize the risks associated with transfusion, including infectious and non-infectious complications.

Clinical Considerations

Before transfusion, proper patient identification with two identifiers, blood type verification, and cross-matching are essential. During transfusion, vital signs should be monitored at baseline, 15 minutes after starting, and periodically thereafter. Transfusion reactions may present as fever, chills, urticaria, or hypotension and require immediate cessation of transfusion and prompt medical evaluation.

From the Research

Blood Transfusion Guidelines

• The guidelines for blood transfusion have been a topic of debate, with some studies suggesting a restrictive approach and others advocating for a more liberal strategy 3, 4, 5, 6, 7.
• A restrictive red blood cell transfusion threshold, typically defined as a hemoglobin concentration <7 to 8 g/dL, has been recommended for most hospitalized patients, including those with stable cardiovascular disease (CVD) 3, 5.
• However, recent evidence suggests that a liberal transfusion strategy may be associated with improved safety for hospitalized patients with stable CVD and/or acute coronary syndromes (ACS) 3, 6.
• The use of restrictive transfusion strategies has been shown to reduce the risk of receiving a red blood cell transfusion, the volume of red blood cells transfused, and hospital mortality, but may not impact the rate of adverse events compared to liberal transfusion strategies 4, 5.

Transfusion Triggers

• The choice of transfusion trigger, whether restrictive or liberal, can have significant implications for patient outcomes, including the risk of major adverse coronary events (MACE) and death 6.
• A liberal strategy has been shown to decrease the relative risk of MACE in CVD patients not undergoing cardiac interventions, but may increase mortality in patients without known CVD 6.
• The optimal transfusion trigger may vary depending on the patient population, with some studies suggesting that a restrictive strategy is safe for critically ill trauma patients 7.

Clinical Outcomes

• The clinical outcomes associated with restrictive and liberal transfusion strategies have been evaluated in several studies, with mixed results 3, 4, 5, 6, 7.
• Restrictive transfusion strategies have been shown to reduce the risk of cardiac events, rebleeding, and bacterial infections, but may not impact functional recovery or hospital length of stay 4, 5.
• Liberal transfusion strategies, on the other hand, may be associated with improved safety and reduced risk of MACE in certain patient populations, but may also increase mortality in others 6.