Transfusion Decision for Hemoglobin 68 g/L
For a hemodynamically stable patient with hemoglobin of 68 g/L (6.8 g/dL), you should transfuse immediately regardless of symptoms, as this level is critically low and falls well below the established threshold where transfusion is almost always indicated. 1, 2
Why Immediate Transfusion is Indicated
At hemoglobin 68 g/L, the patient is at the threshold where transfusion is almost always necessary, particularly when anemia is acute. 2 The AABB guidelines strongly recommend transfusion for hospitalized adults when hemoglobin is less than 70 g/L. 1 This represents a critical level where compensatory mechanisms may already be failing, and waiting for symptoms to develop could be dangerous. 1
The Evidence Base
The AABB guidelines from 2012 established restrictive transfusion thresholds of 70-80 g/L for most hospitalized patients based on large randomized trials. 3 However, these guidelines explicitly state that no recommendations can be made about using symptoms alone to guide transfusion below 80 g/L (8 g/dL), because the FOCUS trial permitted transfusion for all patients with hemoglobin below this threshold. 3
The symptom-based approach is only supported for hemoglobin concentrations of 80 g/L or greater, not below. 3 At 68 g/L, you are in uncharted territory where the evidence does not support withholding transfusion based on absence of symptoms.
Transfusion Protocol
Administer 2-3 units of packed red blood cells initially to achieve a safer hemoglobin level, as each unit typically increases hemoglobin by approximately 10-15 g/L. 1 This will bring the patient into a safer range of 70-90 g/L. 1
After initial correction:
- Give subsequent transfusions as single units in the absence of active hemorrhage 1, 2
- Reassess clinical status and measure hemoglobin after each unit before administering additional blood 1, 2
- Target hemoglobin of 70-90 g/L for most patients 1
Special Considerations
Patients with Cardiovascular Disease
If the patient has preexisting coronary artery disease or heart failure, the threshold for transfusion is even more clear-cut, as these patients may require transfusion at the higher end of the 70-80 g/L range. 1, 2 The restrictive strategy for cardiovascular patients still supports transfusion at 70-80 g/L. 3
Critically Ill Patients
For mechanically ventilated or critically ill patients, transfusion is clearly indicated at 68 g/L, with no benefit shown for liberal strategies targeting hemoglobin >100 g/L. 1
Critical Pitfalls to Avoid
Do not delay transfusion waiting for symptoms to develop at this critically low hemoglobin level—compensatory mechanisms may already be failing, and the absence of symptoms does not indicate safety at this threshold. 1 The evidence supporting symptom-based transfusion decisions applies only to hemoglobin levels of 80 g/L and above, not below. 3
Avoid overtransfusion: Once hemoglobin reaches 70-90 g/L, reassess before giving additional units to prevent transfusion-associated circulatory overload. 1 Liberal transfusion strategies (targeting >100 g/L) provide no benefit and may increase complications. 1, 2
Do not base the decision solely on hemoglobin level in isolation—assess for hemodynamic instability, active bleeding, and signs of inadequate oxygen delivery—but at 68 g/L, these assessments support rather than replace the decision to transfuse. 1, 2