The Validity of a Seismocardiography Device to Estimate Peak Oxygen Uptake in Patients Awaiting Major Elective Surgery

Physical fitness levels of people waiting for a planned operation are often measured using an exercise test. This is because fitness levels help doctors make a plan to improve each person's chances of a successful recovery after their planned operation. The exercise test requires skilled staff, expensive equipment, a 1 hour appointment, and the patient to exercise heavily during the test.

Ventriject, a small to medium sized enterprise, have designed a device called Seismofit that estimates fitness levels of people from a measurement taken whilst laying down. It measures the vibrations of the chest wall caused by the beating heart and uses this information with additional information, such as height, weight and sex, to estimate fitness. The measurement takes around 5 minutes to perform, does not require heavy exercise, expensive equipment or skilled staff.

The Seismofit device was shown to be accurate in young fairly fit people. It has not been tested in people who undergo an exercise test before an operation, who are less fit on average compared to the people that the device was originally tested on. It is likely that the calculations used to estimate fitness levels with the Seismofit device will need to be adjusted for people waiting for an operation. There are two parts to this study. The first part aims to estimate up to 50 people's fitness with the Seismofit device and use directly measured fitness from their standard exercise test before their operation to adjust the calculations for estimating fitness. The second part of this study aims to have a further 50 people undergo the Seismofit device measurement and compare the estimated fitness level with the results from the standard exercise test before an operation. This is to see if the Seismofit device is valid at estimating fitness in people awaiting surgery.