Interview Transcript

Katie Warnaby: Developing slow-wave activity saturation to mark depth of anaesthesia

Introduction

My name is Katie Warnaby, and I’m a senior research scientist in the Nuffield Department of Clinical Neurosciences, and I received MRC Confidence in Concept Funding.

What is slow-wave activity saturation (SWAS)?

So slow-wave activity saturation is an interesting change in the electrical activity of the brain that we think signals when people lose perception of the outside world under anaesthesia, and we discovered it during some functional imaging experiments where we were trying to look at the brain and see how individuals’ brain activity changes as they experience an anaesthetic. Once they became unresponsive we saw a really interesting change in the slow-wave frequencies of the brain. We saw that this change in the electrical activity signalled a very different change in how the brain processed stimuli under anaesthesia, and we think that this point indicates where they lose perception of the outside world. What this means is if we have an endpoint that we can deliver anaesthesia too in the brain, that we can give them just the right amount of anaesthesia to make sure that they’re switched off. 

How did MRC Confidence in Concept allow you to advance your research into SWAS?

So we received two separate Confidence in Concept grants, and the first one allowed us to try and see if SWAS occurs clinically, so look at clinical data sets recorded during surgical anaesthesia. And then the second one was to develop a real-time model, so we can try and deliver anaesthesia to achieve SWAS, and this would really form the first stage of a depth of anaesthesia monitor, and allow really to show that we can achieve SWAS on an individual basis, but also that it does equal perception loss for an individual when they’re under anaesthesia.

What are your aspirations for the future of your research?

So the plan, or we have already put an application in for MRC Development Pathway Funding Scheme, and this will provide funds to further develop this model, and also try and deliver anaesthesia to patients and show that it improves their outcomes after surgery.