Blood Doping - a Literature Review*

Br. J. Sp. Med; Vol 23 Review Br J Sports Med: first published as 10.1136/bjsm.23.2.84 on 1 June 1989. Downloaded from Blood doping - a literature review* Mark Jones' MB, BS, Dip Sports Med and Dan S Tunstall Pedoe2 DPhil, FRCP There is increasing evidence that the technique of reinfus- Heterologous blood doping involves the infusion of blood ing an athlete's stored blood prior to competition to im- from one or more cross-matched donors. prove performance has been used on many occasions. Although early experimental results were controversial and the precise mechanism by which the technique improves Techniques of blood doping performance is still debated, there is now strong evidence that if the blood doping produces a sufficient rise in total red cell mass there are significant improvements in Heterologous blood doping physiological variables such as maximum oxygen uptake, Use of a matched blood donor has the advantage that lactate buffering and thermoregulation. These physiologi- the athlete does not have to suffer the detraining ef- cal changes are matched by improvements in endurance fects of venesection. The blood can be used im- performance. These may persist in diminishing degree for mediately and, if so, has not suffered any deleterious several weeks, but have to be weighed against the detraining effect produced by the repeated venesection required to effects from storage. The disadvantages are the poten- obtain an adequate amount of stored blood for autologous tial transfer of infection, such as hepatitis and AIDS, reinfusion. and possibilities of transfusion reactions. Heterolog- Experimental evidence suggests that the transient in- ous blood transfusion or packing is also easier to detect crease in blood volume and cardiac output following rein- with an appropriate blood sample. fusion is too short lived to be of any real importance and the major effect is related to the increase in total red blood cell Autologous blood doping mass and haemoglobin enabling an increased transport of oxygen and therefore a potentially greater reserve of blood Autologous blood doping involves removing two which can be diverted to non-exercising tissues to improve units of the athlete's blood, storing the blood and then thermoregulation. The increased red cell mass also im- reinfusing it about seven days prior to the athletic con- http://bjsm.bmj.com/ proves lactate buffering. Although these benefits have been test. Venesection needs to be performed at least three shown in several studies the increases in performance and weeks before reinfusion to allow the subject's haemo- measured physiological parameters do not bear a direct globin to recover to normal levels1. An interval of eight relationship to the changes in haematological variables. to twelve weeks is preferable in order to allow the Blood doping is of considerable importance, not only as athlete not only to regain his haemoglobin, but to get an abuse of fair competition, but also because of the light it back to his previous level of fitness and overcome the throws on the physiological limits to endurance perform- detraining effect of blood donation2. ance. It has reawakened controversy as to whether oxygen on September 28, 2021 by guest. Protected copyright. transport is the limiting factor in endurance. The utility of autologous blood doping depends very much on how the blood is stored. Definitions Conventional storage Blood doping, blood boosting, blood packing or induced In the conventional blood bank method, whole blood erythrocythaemia are terms used to describe the infusion of is citrated and refrigerated at 40C. Despite the addition red blood cells to increase aerobic power. of preservatives and anticoagulants, the blood de- Autologous blood doping refers to the infusion of the sub- teriorates steadily, the red cells becoming progres- ject's own stored blood. sively less flexible and more fragile3'4. There is an increase in blood viscosity resulting from this' and 'Dr MarkJones, 64 Seaforth Avenue, Oatley, Sydney, Australia 2223 increased brittleness of the red cells means that these 2Dr Dan S. Tunstall Pedoe, Medical Director, The London Sports cells can fragment on reinfusion1'5. Six to seven per- Medicine Institute, c/o Medical College of St Bartholomew's cent of the stored red cells are lost each week and Hospital, Charterhouse Square, London EC1M 6BQ because of this steady deterioration blood is not transfused after three weeks of conventional storage in the United States of America and after four weeks in Scan- *This literature review is a shortened and edited version of a thesis dinavia. By that time between 30 and 40 per cent of the submitted by Dr Mark Jones as part of the London Hospital Sports red blood cells may have been lost or be of no practical Medicine Diploma Course June 1988. benefit when reinfused6. Conventional blood storage therefore is of ©) 1989 Butterworth & Co (Publishers) Ltd minimal, 0306-3674/89/020084-05 $03.00 if any, practical use for autologous blood doping, but 84 Br. J. Sp. Med., Vol. 23, No. 2 Blood doping - a literature review: M. Jones and D.S. Tunstall Pedoe could be used as a short term measure for heterolog- creased to a greater degree" 2'7-'0. This often gives rise ous blood transfusion. For autologous blood doping, to a reduction in haemoglobin concentration and so the athlete is unlikely to have recovered fully from called athletes anaemia or pseudoanaemia, which has Br J Sports Med: first published as 10.1136/bjsm.23.2.84 on 1 June 1989. Downloaded from blood donation by the time the blood is transfused been well documented. (See Review, pp 81.) back and so although there may be some improvement The increased blood volume of endurance athletes above previous peak performance, the full potential gives the heart a greater preload and thus improved advantage would not be gained. stroke volume and maximum cardiac output. This, to- gether with the improved vascularization of the muscle which results in greater oxygen extraction from the High glycerol freezing blood (lower mixed venous blood oxygen saturation), helps the athlete obtain very high levels of oxygen up- An elaborate technique can be used for almost indefi- nite storage of red cells"4. This technique is used take and utilization for sustained periods of endurance routinely for rare blood types and is being increasingly work. The increased plasma volume also allows a used for autologous blood transfusion where patients greater blood flow to the skin to help dissipate heat are facing a major operation and only wish to receive and gives a greater latitude for dehydration. Since the their own blood. The blood is centrifuged and glycerol endurance athlete often has a low haematocrit with a added to the high concentration of red cells which are below normal blood viscosity, dehydration is poten- then frozen at -80°C in liquid nitrogen. For reinfu- tially better tolerated since both hypovolaemia and a sion, the cells are carefully thawed and undergo a rise in blood viscosity to above normal levels would re- series of washes of increasing osmolality to remove the quire a much greater fluid loss. glycerol. They are then resuspended in normal saline and reinfused in a suspension with haematocrit of Blood transfusion approximately 50 per cent. Blood transfusion does produce a transient increase in The ageing of the red blood cells is suspended by blood volume, stroke volume and cardiac output but freezing and there is a total loss of only 15 per cent of work by Guyton and Richardson1'1,2 shows that this the red cells during the total handling process" 6. Blood effect only lasts a few minutes in experimental animals can be stored for up to ten years using this technique since the increased capillary pressure causes plasma and the technique maximises the recovery ofred blood transudation and loss of blood plasma which buffers cells and ensures that an adequate interval can be ob- any attempt to increase blood volume artificially'3'4. tained between venesection and reinfusion of the Studies in man show most plasma shift has occurred blood for blood doping. within one hour of transfusion and whole blood transfusion has the same effect as giving packed cells in the normal subject, a normovolaemic polycythaemial15' 6. Hypotheses and experimental basis of There is no measurable increase in blood volume 24 blood doping hours later617'18, whether measured indirectly or using a labelled albumin method to confirm blood Blood doping could be ergogenic through its effect on volume'8"9. http://bjsm.bmj.com/ oxygen carriage by producing a polycythaemia and In a series of studies on five healthy young men, blood volume and cardiac output. Kenstrup and Ekblom showed that V02 max appeared to be directly related to the total red cell mass rather Oxygen carriage than the blood volume or the haemoglobin concentra- Supporters of blood doping claim that it increases oxy- tion3. Blood withdrawal caused a fall in V02 max which gen carriage by the blood. As each gram of haemo- was not increased by volume expansion. Volume ex- globin if fully saturated carries 1.34 ml of oxygen, an pansion alone causing a drop in haemoglobin had no on September 28, 2021 by guest. Protected copyright. increase of, say, 2 g of haemoglobin per 100 ml blood effect on VO2 max whereas a reinfusion of red blood increases potential oxygen carriage per litre of blood cells causing an elevated haemoglobin concentration by, say, 25 ml. Assuming a mixed venous saturation of and total red blood cell mass increased the V02 max- fifty per cent, half of this would be available at the These findings reinforce the view that the endurance working muscle and at an exercise cardiac output of, runner with a raised total red cell mass but a low nor- say, 24 litres per minute 300 ml of extra oxygen could mal haemoglobin (i.e.

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