None listed
Conditions
Brief summary
Emergence delirium is a distressing complication of surgery and anaesthesia which is common in the elderly population. It is associated with increased morbidity, mortality, hospital length of stay, discharge to residential care and future cognitive decline. From our previous work we have observed that emergence delirium seems to occur less frequency when alpha activity measured from frontal EEG lead is strong and maintained during emergence from anaesthesia. We plan to conduct a 2 by 2 factorial study to assess the efficacy of 2 interventions which we hope may prevent emergence delirium. Intervention 1 is the use of real-time frontal analysis and anaesthetic and opioid levels to guide anaesthesia to optimise alpha activity. Intervention 2 is the conversion from volatile (gas-based) anaesthesia to propofol anaesthesia for the emergence (waking) phase of anaesthesia. We aim to determine if these interventions are successful in improving the observed alpha activity and subsequently reduce the incidence of emergence delirium in this high risk population
Interventions
2 by 2 factorial design
INTERVENTION 1: Active manipulation of volatile anaesthesia and opioid to maximise frontal EEG alpha power. The frontal EEG will be continuously analysed and dose-response curves created during the anaesthetic. These will be used to guide bolus dosing of intravenous fentanyl, an opioid, and to guide the (inhaled) concentration of volatile anaesthesia administered. The bolus doses and maximum and minimum levels will be determined in conjunction with the attending anaes
2 by 2 factorial design INTERVENTION 1: Active manipulation of volatile anaesthesia and opioid to maximise frontal EEG alpha power. The frontal EEG will be continuously analysed and dose-response curves created during the anaesthetic. These will be used to guide bolus dosing of intravenous fentanyl, an opioid, and to guide the (inhaled) concentration of volatile anaesthesia administered. The bolus doses and maximum and minimum levels will be determined in conjunction with the attending anaesthetist and will be based on previous responses in a dynamic process. INTERVENTION 2: Conversion from inhaled volatile to propofol (intravenous) anaesthesia for emergence from anaesthesia. The volatile anaesthesia will be ceased at time of skin closure and propofol will be given by a target controlled infusion to an effect site concentration of 3ug/ml for at least 2 minutes and then ceased for emergence from anaesthesia
Sponsors
University of Auckland
Study design
Allocation
Randomised controlled trial
Intervention model
Factorial
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
60 Years to No maximum
Healthy volunteers
No
Inclusion criteria
Age > 60 years Capacity for informed consent Undergoing non-cardiac, non-intracranial surgery expected to take 2 hours or longer
Exclusion criteria
Inability to consent Chronic pain Deemed unsuitable for study protocol by anaesthetic care provider
Outcome results
None listed