"The more, the merrier", right?
Anaemia represents a decrease in red cell mass compared to plasma volume, and a reduction in the oxygen-carrying capacity of blood. The WHO definition of anaemia is <130g/L (hct <39%) in males and <120g/L (hct <36%) in females.
In ICU we are regularly faced with anaemic patients who have variable degrees of underlying organ dysfunction. Transfusion of red cells may improve oxygen delivery, but critically ill patients may be more susceptible to the microcirculatory complications and immunosuppressive effects of red cells. Can the evidence guide our practice regarding transfusion of red cells?
The TRICC trial (NEJM 1999; 340: 409-17)
Anaemia represents a decrease in red cell mass compared to plasma volume, and a reduction in the oxygen-carrying capacity of blood. The WHO definition of anaemia is <130g/L (hct <39%) in males and <120g/L (hct <36%) in females.
In ICU we are regularly faced with anaemic patients who have variable degrees of underlying organ dysfunction. Transfusion of red cells may improve oxygen delivery, but critically ill patients may be more susceptible to the microcirculatory complications and immunosuppressive effects of red cells. Can the evidence guide our practice regarding transfusion of red cells?
The TRICC trial (NEJM 1999; 340: 409-17)
- 838 anaemic critically ill patients in Canada
- Hb <90g/L within 72hrs of admission
- randomized to restrictive (Hb 70g/L) or liberal (Hb 100g/L) transfusion triggers
- used non-leukodepleted blood (ie. those who got more blood may not see much benefit due to nasty white cells!)
- Overall 30-day mortality the same
- In-hospital mortality less in restrictive group (22.2% vs 28.1%, p=0.05)
- Mortality less in restrictive group with Age <55 (5.7% vs 13%, p=0.02) and APACHE II <20 (8.7% vs 16.1%, p=0.03)
- No difference in patients with clinically significant cardiac disease
- Liberal strategy group had more cardiac events (APO, AMI) while in ICU
