Hematology Question 20 Instructor

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)
Apache II <20* 16% mortality 8.7% mortality (p=0.03)

*Illustrates statistically significant results

Carson JL et al. Red blood cell transfusion: a clinical practice guideline from the AABB*. Ann Intern Med. 2012 Jul 3;157(1):49-58

Hebert et al. A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care. Transfusion Requirements in Critical Care Investigators, Canadian Critical Care Trials Group. NEJM 1999;340:409-17

Subscribe to Pearls

Uncle Sam wants you to subscribe to Medical Pearls

Subscribe today! It’s always free, and you can easily unsubscribe at any time. We will never share your email address. Subscribe to...

Multiple Pearls
Cardiology Pearls
Endocrinology Pearls
Hematology Pearls
Nephrology Pearls
Rheumatology Pearls
Transplant Pearls
General Internal Medicine Pearls
Instructor Pearls

Subscribe to receive your pearls today—it's free!