Our work has demonstrated that use of the VPCML in patients up to 70kg can have a significant effect in reducing blood usage in our surgical population. Patients are selected primarily on the basis of weight, but factors such as disease state, lean body mass and age are also considered. Our circuit emphasizes low priming volume while making provision for extra blood volume reserve capacity if required. The perfusion techniques we use with the VPCML include high blood flow rates (70-80ml/min/kg); careful attention to sweep gas flow rates throughout the perfusion; and a standard hypothermia condition of 22°C. We have found it particularly important to maintain close cooperation with the anaesthesiologist to avoid shallow anaesthesia levels during rewarming.