A comparison of single-dose dexmedetomidine or propofol on the incidence of emergence delirium in children undergoing general anaesthesia for magnetic resonance imaging

Abstract Background Although used extensively worldwide, the effects of general anaesthesia on the human brain remain largely elusive. Moreover, general anaesthesia may contribute to serious conditions or adverse events such as postoperative cognitive dysfunction and delirium. To understand the basic mechanisms of general anaesthesia, this project aims to study and compare possible de novo neuroplastic changes induced by two commonly used types of general anaesthesia, i.e. inhalation anaesthesia by sevoflurane and intravenously administered anaesthesia by propofol. In addition, we wish to to explore possible associations between neuroplastic changes, neuropsychological adverse effects and subjective changes in fatigue and well-being. Methods This is a randomised, participant- and assessor-blinded, cross-over clinical trial. Thirty healthy volunteers (male:female ratio 1:1) will be randomised to general anaesthesia by either sevoflurane or propofol. Multimodal magnetic resonance imaging (MRI) of the brain will be performed before and after general anaesthesia and repeated after 1 and 8 days. Each magnetic resonance imaging session will be accompanied by cognitive testing and questionnaires on fatigue and well-being. After a wash-out period of 4 weeks, the volunteers will receive the other type of anaesthetic (sevoflurane or propofol), followed by the same series of tests. Primary outcomes: changes in T1-weighted 3D anatomy and diffusion tensor imaging. Secondary outcomes: changes in resting-state functional magnetic resonance imaging, fatigue, well-being, cognitive function, correlations between magnetic resonance imaging findings and the clinical outcomes (questionnaires and cognitive function). Exploratory outcomes: changes in cerebral perfusion and oxygen metabolism, lactate, and response to visual stimuli. Discussion To the best of our knowledge, this is the most extensive and advanced series of studies with head-to-head comparison of two widely used methods for general anaesthesia. Recruitment was initiated in September 2019. Trial registration Approved by the Research Ethics Committee in the Capital Region of Denmark, ref. H-18028925 (6 September 2018). EudraCT and Danish Medicines Agency: 2018-001252-35 (23 March 2018). www.clinicaltrials.gov, ID: NCT04125121. Retrospectively registered on 10 October 2019.

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Exposure to surgery under general anaesthesia and brain magnetic resonance imaging changes in older adults

British Journal of Anaesthesia ◽

10.1016/j.bja.2019.08.024 ◽

2019 ◽

Vol 123 (6) ◽

pp. 808-817 ◽

Cited By ~ 6

Author(s):

Juraj Sprung ◽

S. Chandralekha Kruthiventi ◽

David O. Warner ◽

David S. Knopman ◽

Ronald C. Petersen ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Older Adults ◽

Magnetic Resonance ◽

General Anaesthesia ◽

Brain Magnetic Resonance Imaging ◽

Resonance Imaging

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Cerebral Functional Magnetic Resonance Imaging Activation Modulated by a Single Dose of the Monoamine Neurotransmission Enhancers Fluoxetine and Fenozolone during Hand Sensorimotor Tasks

Journal of Cerebral Blood Flow & Metabolism ◽

10.1097/00004647-199912000-00010 ◽

1999 ◽

Vol 19 (12) ◽

pp. 1365-1375 ◽

Cited By ~ 50

Author(s):

Isabelle Loubinoux ◽

Keder Boulanouar ◽

Jean-Philippe Ranjeva ◽

Christophe Carel ◽

Isabelle Berry ◽

...

Keyword(s):

Magnetic Resonance Imaging ◽

Single Dose ◽

Magnetic Resonance ◽

Functional Magnetic Resonance Imaging ◽

Motor Activity ◽

Healthy Subjects ◽

Drug Effects ◽

Functional Magnetic Resonance ◽

Resonance Imaging

Fluoxetine inhibits the reuptake of serotonin, and dextroamphetamine enhances presynaptic release of monoamines. Although the excitatory effect of both noradrenaline and dopamine on motor behavior generally is accepted, the role of serotonin on motor output is under debate. In the current investigation, the authors evidenced a putative role of monoamines and, more specifically, of serotonin in the regulation of cerebral motor activity in healthy subjects. The effects on cerebral motor activity of a single dose of fluoxetine (20 mg), an inhibitor of serotonin reuptake, and fenozolone (20 mg/50 kg), an amphetamine-like drug, were assessed by functional magnetic resonance imaging. Subjects performed sensorimotor tasks with the right hand. Functional magnetic resonance imaging studies were performed in two sessions on two different days. The first session, with two scan experiments separated by 5 hours without any drug administration, served as time-effect control. A second, similar session but with drug administration after the first scan assessed drug effects. A large increase in evoked signal intensity occurred in the ipsilateral cerebellum, and a parallel, large reduction occurred in primary and secondary motor cortices (P < 10–3). These results are consistent with the known effects of habituation. Both drugs elicited comparable effects, that is, a more focused activation in the contralateral sensorimotor area, a greater involvement of posterior supplementary motor area, and a widespread decrease of bilateral cerebellar activation (P < 10–3). The authors demonstrated for the first time that cerebral motor activity can be modulated by a single dose of fluoxetine or fenozolone in healthy subjects. Drug effects demonstrated a direct or indirect involvement of monoamines and serotonin in the facilitation of cerebral motor activity.

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EFFECT OF GENERAL ANAESTHESIA ON THE MAGNETIC RESONANCE IMAGING SIGNAL FROM THE BRAIN

British Journal of Anaesthesia ◽

10.1093/bja/62.6.694 ◽

1989 ◽

Vol 62 (6) ◽

pp. 694-696 ◽

Cited By ~ 10

Author(s):

A. WHITFIELD ◽

R.H.B. DOUGLAS

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

General Anaesthesia ◽

Resonance Imaging ◽

Magnetic Resonance Imaging Signal ◽

The Brain

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Midventricular Takotsubo cardiomyopathy associated with ventricular fibrillation during general anaesthesia in a 34-year-old woman: Insight from cardiac computed tomography and magnetic resonance imaging

Archives of Cardiovascular Diseases ◽

10.1016/j.acvd.2011.04.016 ◽

2012 ◽

Vol 105 (5) ◽

pp. 329-331 ◽

Cited By ~ 6

Author(s):

Jérôme Caudron ◽

Nathalie Rey ◽

Jean-Nicolas Dacher

Keyword(s):

Magnetic Resonance Imaging ◽

Computed Tomography ◽

Magnetic Resonance ◽

Ventricular Fibrillation ◽

General Anaesthesia ◽

Takotsubo Cardiomyopathy ◽

Cardiac Computed Tomography ◽

Resonance Imaging

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Asymptomatic oropharyngeal lipoma complicating intubation

The Journal of Laryngology & Otology ◽

10.1258/0022215054273106 ◽

2005 ◽

Vol 119 (6) ◽

pp. 483-485 ◽

Cited By ~ 4

Author(s):

J Rimmer ◽

A Singh ◽

C Irving ◽

D J Archer ◽

P Rhys Evans

Keyword(s):

Magnetic Resonance Imaging ◽

Magnetic Resonance ◽

Airway Obstruction ◽

General Anaesthesia ◽

Supraglottic Airway ◽

Resonance Imaging ◽

Rare Tumours ◽

Magnetic Resonance Imaging Mri ◽

Anaesthetic Assessment

Oropharyngeal lipomas are rare tumours. We present the case of a young man with an asymptomatic lipoma almost completely occluding his supraglottic airway, found on magnetic resonance imaging (MRI) for a separate oral cavity lesion. Pre-operative anaesthetic assessment was undertaken because of the risk of airway obstruction at induction of general anaesthesia. We discuss the awake fibre-optic technique used for induction, as well as the treatment and follow-up of these tumours. This case highlights the need for formal anaesthetic assessment, in such cases, to avoid total airway obstruction at induction of general anaesthesia. It also emphasizes the extent of supraglottic obstruction that can be present without giving rise to any symptoms.

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