1. What is really dangerous: anaemia or transfusion?
A. Shander, M. Javidroozi, S. Ozawa, G.M.T. Hare 
British Journal of Anaesthesia 
Volume 107, Pages i41-i59 (December 2011)
DOI: /bja/aer350
Copyright © 2011 The Author(s) Terms and Conditions

2. Fig 1
Comparison of oxygen transport from the microcirculation at physiological Hb concentrations and during anaemia.40–45 ATP, adenosine triphosphate; Hb, haemoglobin in g litre−1; HIFα, hypoxia-inducible factor alpha; Po2, partial pressure of oxygen in kPa.
British Journal of Anaesthesia  , i41-i59DOI: ( /bja/aer350)
Copyright © 2011 The Author(s) Terms and Conditions

3. Fig 2
Estimated risk of death at various Hb concentrations. Data are based on a subset of patients (n=19) who could not be transfused, and had agreed to receive an Hb-based oxygen carrier because or in anticipation of severe anaemia, but did not receive the product for various reasons.67 Risk of mortality for each Hb concentration was calculated using an equation obtained from running a logistic regression model with final status (dead/alive) as the dependent and Hb as the independent variables.
British Journal of Anaesthesia  , i41-i59DOI: ( /bja/aer350)
Copyright © 2011 The Author(s) Terms and Conditions

4. Fig 3
Causal pyramid depicting the theoretical relationship of anaemia and its accomplices in causing unfavourable outcomes. Positive causal links are denoted by solid arrows and indicate that the first node (or increase in its severity or dose in the case of transfusions) would cause the second node (or increase in its severity or dose in the case of transfusions). A negative causal link denoted by dashed arrow exists between transfusion and anaemia as the former is expected to reduce the severity of the latter (albeit temporarily), but the effectiveness of this measure in terms of improving oxygen delivery and consumption is debated. Unfavourable outcomes can include occurrence of new morbid events or exacerbation of pre-existing ones, which could lead to increased chronic illness/inflammation burden and further reinforce the loop.
British Journal of Anaesthesia  , i41-i59DOI: ( /bja/aer350)
Copyright © 2011 The Author(s) Terms and Conditions