 Background: Different anaesthetic agents have been shown to have different protective effects upon heart, brain and renal function under ischaemic conditions oxygen starvation. Cardiopulmonary bypass takes over the work of the heart and the lungs during heart surgery, but oxygenation of vital organs such as the brain and heart may not be perfect, and can produce brain or heart damage as a consequence. Propofol and desflurane are commonly used anaesthetic agents, and there has been recent research to suggest that anaesthetic agents may provide some protection during periods where inadequate oxygenation occurs, with the potential to reduce the degree of organ damage. Both types of anaesthetics are used for cardiac surgery with anaesthetists choosing between them largely on the basis of personal preference. 