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Copyright ©2009 The WJG Press and Baishideng.
World J Gastroenterol. Oct 7, 2009; 15(37): 4686-4694
Published online Oct 7, 2009. doi: 10.3748/wjg.15.4686
Table 1 Transfusion haemoglobin threshold according to patient’s age and characteristics and type of anaemia
Haemoglobin threshold (g/dL)Patients characteristics and type of anaemia
< 5Patients with chronic anaemia and without risk factors1
< 6Patients with symptomatic2 chronic anaemia and without risk factors
Acute anaemia in younger patients
< 7Asymptomatic chronic anaemia in patients with risk factors
Acute anaemia in surgical and critically ill patients
< 8Acute anaemia in surgical patients older than 65 yr
< 9Acute anaemia in patients with organ dysfunction3
< 10Patients with massive transfusion
> 10Do not transfuse
Table 2 Theoretical reasons supporting the restrictive or the liberal use of allogeneic red cells in normovolemic patients
Rationale supporting the liberal use of red cells
Augmenting O2 delivery may improve patient survival and functional recovery
Increased risk of coronary ischaemia due to increased demand
Reduces respiratory work
Age, disease severity and drugs may interfere adaptation to anaemia
Improved safety margin if further blood loss
Increased safety of donor blood products
Rationale supporting the restrictive use of red cells
Moderate anaemia has not proved to increased mortality
Red cell transfusions impair microcirculatory flow
Progressive loss of red cell functionality during storage
Pathologic supply dependency is rare
Risk of pathogen transmission
Immunodepression causing increased infections and tumor relapse following transfusion
Risk of TRALI and TACO
Blood products are increasingly scarce and expensive
Table 3 Risks or hazards of allogeneic blood transfusion
Acute transfusion reactions
Immunologic reactions
Acute haemolytic reaction (or THRs)
Febrile non-haemolytic reaction
Allergic reactions: Urticaria and anaphylaxis
Acute non-cardiogenic pulmonary edema: TRALI
Alloimmunization with acute platelet destruction
Non-immunologic reactions
Bacterial contamination
TACO
Hypotensive reaction
Non-immunologic haemolysis
Others: Hypocalcemia, hyperkalemia (cardiac arrest), hypothermia, hyperglycemia, etc
Delayed transfusion reactions
Immunologic reactions
Delayed haemolytic reaction
Alloimmunization against blood cell antigens (also platelets and leukocytes)
Graft vs host disease
Transfusion-related immunomodulation
Post-transfusion purpura
Non-immunologic reaction
Transfusion-transmitted infection: viruses (Hepatitis A, B, C, E, VIH 1-2, West Nile virus, HTLV I-II, Citomegalovirus, Virus Herpes viridae, TTV, SEN-1, SARS, etc), protozoa (malaria, babe biosis, Chagas disease, etc), prion (new variant Creutzfeldt Jacob disease)
Post-transfusion hemosiderosis (iron overload)