Performance of heat exchangers used in whole body perfusion circuits.

The performance of some commonly used heat exchangers has been investigated with particular reference to the effect of varying the water flow. The results demonstrate that there is considerable variation in the performance of most units when the water flow is changed. It is suggested that more information should be provided by the manufacturers of heat exchangers and that there should be a supply of water in cardiothoracic theatres at a sufficient pressure to allow the full performance of the heat exchangers to be realized.