Introduction: Reperfusion of acutely ischaemic tissue may, paradoxically, lead to systemic complications. This phenomenon is believed to be initiated by humoral factors that have accumulated in the ischaemic tissue. The ancient art of venesection may reduce the load of these mediators at the point of reperfusion. The aim of this study is to test if selective venesection, by removing the initial venous return from the ischaemic tissue, can attenuate the systemic effects of the ischaemic-reperfusion injury using a porcine model of acute limb ischaemia. Materials and Methods: The right femoral arteries of anaesthetised female pigs were clamped. Twelve pigs were divided into 2 groups (n = 6 per group). In the treatment group, 5% of blood volume was venesected from the ipsilateral femoral vein upon reperfusion; the other arm served as control. The animals were sacrifi ced after 4 days for histological examination. A pathologist, blinded to the experimental groups, graded the degree of microscopic injury. Results: For the control group, the kidneys showed glomeruli and tubular damage. The livers demonstrated architectural distortion with cellular oedema. There was pulmonary oedema as well as extensive capillary congestion and neutrophil infi ltration. Such fi ndings were absent or reduced in the venesected animals. Consequently, the injury scores for the kidney, lung, liver and heart were signifi cantly less for the venesected animals. Conclusion: Selective venesection reduces the remote organ injuries of the ischaemic-reperfusion phenomenon.
Ischaemia-Reperfusion (I/R) injury describes a paradoxical phenomenon where reperfusion of tissues following a prolonged period of acute onset ischaemia causes further injury both to the tissues involved as well as distant organs uninvolved in the initial ischaemic event. The remote effects of I/R injury are most frequently observed in the lungs.1,2 Such distant effects are associated with the development of the systemic infl ammatory response syndrome (SIRS) and multiple organ dysfunction syndrome (MODS).2,3 Respiratory failure is followed by hepatic, renal and gastrointestinal dysfunction, as well as central nervous system involvement and myocardial failure.4 Consequently, revascularisation of an acutely ischaemic limb is associated with mortality rates of 10% to 20% and morbidity rates of 20% to 30%.5-8
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