Somnus Research

Somnus Scientific is developing real-time blood propofol monitors to provide vital information for clinicians at the bed-side.  The current stage of development is to test the accuracy of its novel sensors with blood taken from patients being anaesthetised with propofol. 

Dr Rebecca Oram at RUH Bath is leading the clinical aspects of the research.  She has obtained consent from 10 patients to take a series of blood samples from them during their operations – usually five separate samples of 12 mls. One sample will be taken before they are anaesthetised and four more while they are unconscious.  Each sample will has its blood cells and liquid (plasma) components separated in the Research Laboratory at the RUH before the plasma is stored at very cold temperatures. The frozen plasma is then transported to the Health Tech Hub at the University of the West of England in Bristol.

This is where a bench top prototype of the new monitor has been set up by the Somnus team. 

Once the samples arrive they are tested in two different ways.  One part of the sample is used on the prototype monitor.  This tests what concentration of propofol the sensors detect in the patient’s plasma.  Another part of the same sample is then tested using a ‘gold standard’ laboratory method on a piece of equipment that is too big and too slow to be of use to clinicians who need rapid results during anaesthesia.   

This research shows us how accurate the Somnus prototype monitor is and supports any design adjustments that need to be made.

Why does this matter?  The whole point of the Somnus monitor is to make it possible for the anaesthetist to see, in real-time, how much propofol is in the patient’s blood.  This allows for a far greater personalisation of the doses given to individual patients.  By not over anaesthetising the patient, or over sedating in non-theatre settings, the anaesthetist can keep the patient comfortable but also speed up recovery and reduce any negative side effects of a deep anaesthetic.

Having a real time blood propofol monitor will change the way we can give anaesthesia and sedation and benefit patients, the NHS and the environment. 

We are very grateful to those patients who have agreed to take part in this research.  Although they do not benefit directly themselves, their willingness to help will contribute to improvements in the care that we can give in the future.