The EPigenetic Consequences in Children of Intravenous vs Volatile Anaesthesia for Surgery (EPIVA)

More than half a million children have an anaesthetic each year in the UK. Though anaesthesia is usually thought to be safe and necessary to improve health, concerns remain the effects that the drugs used may have on brain development in children and the potential long-term consequences for health. The two techniques used to keep someone asleep during anaesthesia are either giving the appropriate drugs through a small plastic tube into a vein or introducing different drugs into the lungs in gas form. Gene expression is the process by which instructions in DNA are used to make products such as proteins. Anaesthetic drugs may change how a child's genes are expressed; a process called epigenetics. Studies have shown that different anaesthetic drugs can cause epigenetic changes in animals and affect the processing ability of their brains. This study will focus on children aged under 3 undergoing general anaesthesia for planned hypospadias surgery (a developmental condition where the look and function of the penis may not be completely normally). Participants will either receive their general anaesthetic in gas form or through directly into their veins - both techniques are commonly used. A small blood sample (between 1 and 2 teaspoons) will be collected at the start and end of the operation whilst under anaesthetic. Samples will be analysed to look for any changes in signals on DNA (epigenetic changes) and other markers. Further analysis may then look at other measures of gene expression and additional processes/markers that could be affected. There is relatively less medical research carried out in children and this work will show whether this type of study is possible in this age-group and provide information for future trials. It will help towards improving our understanding of the effects of anaesthesia ultimately help doctors and families make better informed decisions.

Sex

Male

Minimum age

6 Months

Maximum age

3 Years

Inclusion Criteria:

* Age ≥6 months and ≤ 3 years at time of initial operation
* Undergoing hypospadias surgery
* Maintenance phase of anaesthesia for procedure has an estimated length of ≥1 hour (established through MDT discussion prior to surgery).
* Completed informed consent form (ICF) from legal representative (LR (this is the person who is empowered to give informed consent on behalf of a participant. For most children this will be one or both parents. This may also be a guardian or custodian with legal custody)).

Exclusion Criteria:

* LR unable to provide completed ICF
* Withdrawal of consent at any stage
* Previous exposure to general anaesthesia at any stage of life, including in-utero (through maternal exposure at any stage until delivery)
* Neurodevelopmental/neurodisability diagnosis (given or under investigation) from a paediatric service including autistic specturm disorder (ASD), attention deficit disorder (ADHD), traumatic brain injury (TBI), down's syndrome, cerebral palsy, epilepsy
* Known contraindication to either volatile-based inhalational anaesthesia or TIVA (surgery or participant)
* Clinician refusal

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