Validation of Nexfin Cardiac Output in Elderly Patients With Hip Fracture

Validation of the Nexfin Non-invasive Cardiac Output Monitor in Patients Undergoing Hip Fracture Repair

Measurement of how much blood the heart pumps may be useful in guiding how much intravenous fluid to give patients during surgery. The current monitors either require special drips (arterial and/or central lines) or a probe inserted into the oesophagus (food pipe) which may limit their use. Newer monitors are available which are completely non-invasive and seem to work well in younger patients. Patients with hip fracture are elderly and frail. The investigators wish to see whether the newer non-invasive monitor works well enough compared to the current monitors in this group of patients. If it does this may allow more of these patients to be monitored in this way.

The investigators wish to compare the accuracy of the newer, non-invasive monitor (Nexfin) against a more established minimally invasive monitor (LiDCO). The LiDCO has a calibration system which allows the absolute accuracy of the Nexfin to be established.

Inclusion Criteria:

• Aged over 80
• Able to give their own informed consent

Exclusion Criteria:

• Severe valvular heart disease
• Taking lithium