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Centre for Evidence-
Based Medicine

Therapy: Alternative Clinical Scenario

You are attending in the ICU and are taking care of a 75 year old woman admitted with pneumonia, and requiring ventilatory support. You approach her husband to obtain consent for a blood transfusion. Her Hgb is 8g/dL. She has not had a transfusion in the past. You suggest that she would benefit from having a Hgb greater than 10 g/dl. He is a retired physician and clinical epidemiologist and asks if there is evidence to support having Hgb greater than 10 g/dl. You formulate the question, "In patients who are critically ill, does transfusion to a Hgb of at least 10 g/dL reduce mortality?"

You start up Medline enter "transfusion" and "critical illness" and you find the abstract and commentary for the multicenter, randomized controlled trial assessing transfusion requirements in critical care settings. The abstract looks helpful so you decide to go to the library and copy the original article (NEJM 1999;340:409-17). You return to the ICU waiting area to discuss your findings with the patient's husband.

Read the article and decide:

  1. Is the evidence from this randomized trial valid?
  2. If valid, is the evidence important?
  3. If valid and important, can you apply this evidence in caring for your patient?

Continue to completed worksheet