 Improving or maximising cardiac output in the perioperative setting either through the use of intravenous fluids, or in combination with inotropes has been shown to reduce complication rates following surgery in a variety of settings including those with fractured neck of femurs. A recent meta analysis of optimisation trials has shown that for every 100 patients in whom the intervention is provided, patients will avoid a complication, and length of stay will be reduced by 1 day. Importantly the intervention is also associated with no harm. In 1997 by using the oesophageal Doppler to guide fluid therapy in an attempt to maximise cardiac output, Sinclair managed to reduce the time patients who were operated on for a fractured neck of femur were deemed fit for medical discharge from 15 to 10 days P0.05. Stroke volume was significantly increased in the protocol group, and although postoperative complication rates were not reported in this trial, it is inferred that they were reduced. A similar trial comparing conventional fluid therapy versus therapy guided by either central venous pressure measurements or oesophageal Doppler showed a similar reduction in time to being medically fit for discharge. This trial did report morbidity, which showed a non-significant trend to improvement in subjects who received oesophageal Doppler monitoring. 