School of Medicine
Chair of Anaesthesiology I
Switch off conscious perception
The Chair of Anaesthesiology I focuses its teaching and research on the suppression of conscious perception. Its work also covers pain management, intensive care and emergency medicine. The Chair is based at the Helios University Hospital Wuppertal (HUKW), Department of Anaesthesiology. In day-to-day clinical practice, the Chair’s staff, as part of the hospital team, are responsible for the care of all the hospital’s patients before, during and after operations.
Chair holder
Prof. Dr. med.
Serge Thal
Chair Holder
Faculty of Health (School of Medicine) | Chair of Anaesthesiology I
Heusnerstraße 40
42283 Wuppertal
Research
Mechanisms of action of anaesthesia
At the department, our research focuses, amongst other things, on how anaesthesia affects the brain. We examine electrical and functional changes in brain activity in parallel – this provides insights into the general mechanisms of action of general anaesthesia, which suppress ‘consciousness’ and conscious perception.
In studies involving healthy volunteers and patients, we have been able to identify parameters of electroencephalography (EEG) – a method for measuring the brain’s electrical activity – and of the auditory evoked potential (AEP) – the response to auditory stimuli – that reflect the clinical state (awake/unconscious) of the individuals. Changes in clinical state can be clearly detected over time in the brain’s electrical signal; however, spatial localisation within the brain, particularly in deep regions, has so far been significantly limited.
fMRI on volunteers and patients
What happens in the brain during anaesthesia-induced unconsciousness? To find this out, we are supplementing the temporal data from electroencephalography (EEG) and auditory evoked potentials (AEP) with functional magnetic resonance imaging (fMRI) – which records changes in brain metabolism during unconsciousness. However, imaging techniques such as fMRI do not provide any insight into what caused these changes. It is only when combined with brain electrical data that the underlying mechanisms can be explained.
In particular, parallel measurements of cortical brain activity – which takes place in the cerebral cortex and is responsible for higher-order functions such as thinking and perception – and subcortical activity, which occurs in deeper regions and controls basic functions and emotions, are likely to help find explanations for the altered brain metabolism. The coordinated investigation of electrical signals at the cellular, superficial (cortical) and deep (subcortical) levels, as well as the (parallel) recording of changes in brain metabolism, therefore represent a promising approach for identifying the essential structures underlying anaesthesia-induced unconsciousness.
Understanding the perception of pain
The aim of analgesia is to prevent or reduce the perception of pain. It is the only one of the three main components of general anaesthesia that cannot yet be measured directly and objectively – even though it influences the entire anaesthetic process. Quantification is therefore essential to prevent pain-related intra- and post-operative complications and to ensure the safe management of general anaesthesia.
The working group dealing with this topic is investigating ways in which the analgesic and antinociceptive components of anaesthesia, which counteract the perception of pain, can be specifically assessed. It is also investigating the interplay and interaction with the hypnotic component of anaesthesia.
Making it possible to measure the depth of anaesthesia
In recent years, there has been a growing range of devices available that enable the measurement of ‘anaesthetic depth’ based on the effect of anaesthetics on the brain. They analyse spontaneous (electroencephalography, EEG) or stimulus-evoked activity (acoustically evoked potentials, AEP). As a rule, index values are calculated from this data which reflect the ‘depth of anaesthesia’ or the hypnotic component of anaesthesia.
The Neuromonitoring Working Group is investigating these devices. It also develops and evaluates algorithms that detect consciousness and unconsciousness. The research is carried out in close cooperation with the Department of Anaesthesiology at the Technical University of Munich.
Predicting the course of a disease
In health care research, we investigate predictors of clinical outcome; these can help to predict the course and outcome of a disease or treatment. Furthermore, at the Chair, we investigate factors that influence the prevalence of a disease in a specific population group (morbidity) and mortality. This research is carried out both in independent projects and in multicentre studies.
Mechanisms of action of anaesthesia
At the department, our research focuses, amongst other things, on how anaesthesia affects the brain. We examine electrical and functional changes in brain activity in parallel – this provides insights into the general mechanisms of action of general anaesthesia, which suppress ‘consciousness’ and conscious perception.
In studies involving healthy volunteers and patients, we have been able to identify parameters of electroencephalography (EEG) – a method for measuring the brain’s electrical activity – and of the auditory evoked potential (AEP) – the response to auditory stimuli – that reflect the clinical state (awake/unconscious) of the individuals. Changes in clinical state can be clearly detected over time in the brain’s electrical signal; however, spatial localisation within the brain, particularly in deep regions, has so far been significantly limited.
fMRI on volunteers and patients
What happens in the brain during anaesthesia-induced unconsciousness? To find this out, we are supplementing the temporal data from electroencephalography (EEG) and auditory evoked potentials (AEP) with functional magnetic resonance imaging (fMRI) – which records changes in brain metabolism during unconsciousness. However, imaging techniques such as fMRI do not provide any insight into what caused these changes. It is only when combined with brain electrical data that the underlying mechanisms can be explained.
In particular, parallel measurements of cortical brain activity – which takes place in the cerebral cortex and is responsible for higher-order functions such as thinking and perception – and subcortical activity, which occurs in deeper regions and controls basic functions and emotions, are likely to help find explanations for the altered brain metabolism. The coordinated investigation of electrical signals at the cellular, superficial (cortical) and deep (subcortical) levels, as well as the (parallel) recording of changes in brain metabolism, therefore represent a promising approach for identifying the essential structures underlying anaesthesia-induced unconsciousness.
Understanding the perception of pain
The aim of analgesia is to prevent or reduce the perception of pain. It is the only one of the three main components of general anaesthesia that cannot yet be measured directly and objectively – even though it influences the entire anaesthetic process. Quantification is therefore essential to prevent pain-related intra- and post-operative complications and to ensure the safe management of general anaesthesia.
The working group dealing with this topic is investigating ways in which the analgesic and antinociceptive components of anaesthesia, which counteract the perception of pain, can be specifically assessed. It is also investigating the interplay and interaction with the hypnotic component of anaesthesia.
Making it possible to measure the depth of anaesthesia
In recent years, there has been a growing range of devices available that enable the measurement of ‘anaesthetic depth’ based on the effect of anaesthetics on the brain. They analyse spontaneous (electroencephalography, EEG) or stimulus-evoked activity (acoustically evoked potentials, AEP). As a rule, index values are calculated from this data which reflect the ‘depth of anaesthesia’ or the hypnotic component of anaesthesia.
The Neuromonitoring Working Group is investigating these devices. It also develops and evaluates algorithms that detect consciousness and unconsciousness. The research is carried out in close cooperation with the Department of Anaesthesiology at the Technical University of Munich.
Predicting the course of a disease
In health care research, we investigate predictors of clinical outcome; these can help to predict the course and outcome of a disease or treatment. Furthermore, at the Chair, we investigate factors that influence the prevalence of a disease in a specific population group (morbidity) and mortality. This research is carried out both in independent projects and in multicentre studies.
Publications
All publications by the Chair of Anaesthesiology I are gradually being included in the university bibliography.
Teaching
The Chair of Anaesthesiology I, in close collaboration with the Chair of Anaesthesiology II at the Cologne-Merheim campus, is responsible for delivering the full anaesthesiology training programme for students in medicine at Witten/Herdecke University.
Our teaching activities are not limited to anaesthesia alone – our remit also includes teaching the theory and practice of emergency and intensive care medicine. The Department is also involved in the teaching of pain and palliative care medicine and the restructuring of these programmes.
During their practical year, we introduce medical students to clinical work in anaesthesiology through one-to-one supervision. This enables them to gain practical experience quickly. We complement this practical work with interdisciplinary clinical year seminars, which take place throughout the year at Helios University Hospital Wuppertal.
It is important to us to teach effectively and sustainably. That is why we are moving away from lecturer-centred knowledge transfer and a ‘school-like’ approach to the degree programme towards a student-centred approach to learning: rather than simply imparting knowledge, we create learning spaces. In this way, students engage with the learning processes they will encounter in their everyday professional lives as doctors. We follow an evidence-based model of cooperative learning: ‘Evidence-Based Teaching’ (EBT) is a teaching and learning process in which scientific findings, practical experience and the needs of both lecturers and students are integrated to ensure the best possible teaching and learning.
Review articles and meta-analyses show that the equivalence of cooperative and traditional teaching methods is demonstrated when it comes to achieving subject-specific learning outcomes. However, when it comes to cross-disciplinary learning objectives, they are significantly superior. As lecturers, we therefore see ourselves in the role of facilitators on an equal footing. We create the conditions under which deep learning and social learning become possible.
Secretariat
Nicole Pöhlmann
Secretariat
Faculty of Health (School of Medicine) | Chair of Anaesthesiology I