None listed
Conditions
Brief summary
This study aims to investigate if markers of neuronal damage (neurofilament light and tau) are associated with general anesthesia and surgery. Specifically, we wish to confirm and expand our recent preliminary findings that this damage is associated with anesthetic type and with clinical outcomes of delirium and postoperative cognitive dysfunction. To establish this, patients undergoing major elective non-cardiac surgery will be randomly allocated to receive sevoflurane maintenance anaesthesia or propofol maintenance anaesthesia. Cognitive and memory testing will take place prior to surgery, at 7 days after surgery and at 3 months after surgery. Tests for delirium and collection of blood samples will also be conducted during the participants' time in hospital.
Interventions
Participants involved in the study will be randomly assigned to either a sevoflurane or propofol maintenance anaesthesia group before undergoing major elective non-cardiac surgery. We will quantitate the change in two blood biomarkers of neurological damage (neurofilament light and tau) to further investigate preliminary evidence that sevoflurane protects against neuronal damage. No further alterations or additions to anaesthetic or surgical technique are required.
Characteristics of both types
Participants involved in the study will be randomly assigned to either a sevoflurane or propofol maintenance anaesthesia group before undergoing major elective non-cardiac surgery. We will quantitate the change in two blood biomarkers of neurological damage (neurofilament light and tau) to further investigate preliminary evidence that sevoflurane protects against neuronal damage. No further alterations or additions to anaesthetic or surgical technique are required. Characteristics of both types of anaesthesia are as follows: TIVA Anaesthesia (Propofol): intravenous remifentanyl infusion 0.3mcgs/kg or 4 nanograms/ml or appropriate dose titrated to effect; propofol TCI 4mcg/ml or titrated to effect; oxygen and air. Volatile Anaesthesia (Sevoflurane): intravenous midazolam up to 5 mg, fentanyl 100 micrograms or as required, induction intravenous propofol 2 mg/kg or as required; inspired sevoflurane concentration at MAC or as required in air and oxygen. General anaesthesia is always administered prior to the commencement of surgery. Specific time frames cannot be provided as this is contingent on the type of surgery, but it generally occurs 10-15 minutes before surgical incision.
Sponsors
St Vincent's Hospital
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Prevention
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
65 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1. 65 years of age 2. Scheduled for elective non-cardiac surgery 3. Undergoing a procedure equally suited to intravenous (TIVA) or volatile anaesthetic management 4. Have no contraindication to neuropsychological testing (e.g. language, visual or hearing impairment) 5. Reside in an accessible proximity to the hospital for neuropsychological testing
Exclusion criteria
1. Pre-existing neurological or clinically evident neurovascular disease (e.g. stroke) 2. Dementia of any aetiology 3. Received a general anaesthetic in previous 6 months 4. Associated medical problems that may lead to significant complications and loss to follow-up
Outcome results
None listed