A 36 year old female is post-op day 3 for a colectomy for ulcerative colitis. She is on oral iron replacement and feels well with a minimal need for analgesia. Her chart indicates that her heart rate was 110 bpm and there is an order for 2 units of packed red blood cells if the Hgb is <100g/L. You question the evidence behind such an order and call the surgical service covering her care.
Points of Discussion: What are the indications for transfusion? Is there any evidence that exists to help with when and how much blood should be transfused?
Indications for Transfusion
- Symptomatic anemia in a NORMOVOLEMIC patient
- Hb <70g/L
- Hb <80g/L in chronic transfusion patients
- Inappropriate if Hb >100g/L
- Atherosclerosis, unstable angina, other cardiac, pulmonary,↑ oxygen consumption, unpredictable bleeding
- DO NOT transfuse based solely on Hb
- Always use Hb in combination with clinical status and history
Discussion Point: The TRICC Trial was a RCT of transfusion requirements in critical care to determine whether a restrictive strategy of red-cell transfusion (i.e. transfuse once Hgb < 70g/L to maintain a Hgb between 70–90g/L) and a liberal strategy (transfuse to keep Hgb >100g/L) produced equivalent results in critically ill patients. Results compared the rates of death from all causes at 30 days and the severity of organ dysfunction.
| Category | Hb >100 | Hb >70 |
| 30 day mortality | 23% | 19% (p=0.11) |
| Overall mortality* | 28% | 22% (p=0.05) |
| Age <55* | Worse | Better (less cardiopulmonary events: TACO, TRALI) (p=0.02) |
| Apache II <20* | 16% mortality | 8.7% mortality (p=0.03) |
*Illustrates statistically significant results
