Midbrain changes due to anaesthesia during routine elective surgery
Research type
Research Study
Full title
The use of non-invasive nasopharyngeal electroencephalography to detect midbrain changes associated with anaesthesia in normal healthy day-case surgical patients
IRAS ID
138286
Contact name
Katie Warnaby
Contact email
Sponsor organisation
University of Oxford
Research summary
Anaesthesia uses different monitoring systems to ensure patient safety during surgery. The brain, where anaesthetic drugs work, is not normally monitored directly. Instead the effects of anaesthesia on the brain are monitored indirectly by clinical observation. Although direct brain monitors do exist, they have been shown to be inconsistent and not specific enough for judging the depth of anaesthesia for the individual.
These brain monitors focus on measuring brain waves accessible from the scalp using electroencephalography (EEG) to record the changes that occur with anaesthesia. Deeper brain structures are increasingly thought to play a greater role in regulating consciousness, in particular the middle of the brain or midbrain. Scientifc evidence suggests that midbrain recordings might give different information to these conventional brain monitors. It might tell us about the body’s subconscious response to surgery. This sort of information is a clinically useful marker of anaesthetic unconsciousness. However the midbrain has not been investigated enough for scientists to be confident in the information it might be able to give.
We propose a simple observational study to establish the potential usefulness of these midbrain recordings as extra markers of anaesthesia-induced unconsciousness. We will use nasophayrngeal EEG, a non-invasive technique already used for epilepsy and sleep diagnostic tests, to record information from the midbrain and make comparisons to standard brain monitoring during elective surgery. Information collected may help design better ways of delivering safe anaesthesia for patients, with the bonus of helping clinicians understand better how anaesthetics work.
This research is partly funded by the Oxford Health Services Research Committee, and partly by internal funding from the study group. It will be recruiting participants and collecting data at Milton Keynes General Hospital (MK6 5LD) and storing, processing and analysing data at the John Radcliffe Hospital (OX3 9DU).
REC name
South Central - Oxford A Research Ethics Committee
REC reference
14/SC/0145
Date of REC Opinion
12 May 2014
REC opinion
Further Information Favourable Opinion