Impact of Propofol Versus Sevoflurane on Incidence of Postoperative Delirium in Elderly Patients After Spine Surgery

Study Overview
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Brief Summary
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Postoperative delirium in older adults is a common and costly complication after surgery. Propofol and sevoflurane are commonly used anesthetics to maintain sedation during spine surgery, and have different sedative and anti-inflammatory effects. The aim of this trial will be compare the impact of propofol versus sevoflurane on incidence of postoperative delirium in elderly patients after spine surgery.

Detailed Description
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Spine surgery is the third most common surgical procedure in older patients. With the increasing number of older patients undergoing spinal surgery, the risk of delirium after spinal surgery is currently expected to increase. The pathophysiological mechanisms of delirium remain poorly understood, leading models include neurotransmitter imbalance and neuroinflammation. Among precipitating factors, drugs (especially sedative hypnotic agents and anticholinergic agents), surgery, anesthesia, high pain levels, anemia, infections, acute illness, and acute exacerbation of chronic illness are the most commonly reported. Propofol and sevoflurane are commonly used anesthetics to maintain sedation during spinal surgery, and induce unconsciousness through different mechanisms. Meanwhile, previous studies have found that propofol and sevoflurane have different anti-inflammatory effects. Given their different sedative and anti-inflammatory effects, propofol and sevoflurane may have different effects on postoperative delirium. There are many studies to explore the effects of propofol and sevoflurane on postoperative delirium, but the conclusions are controversial. Therefore, a randomized, controlled, double-blind clinical study was designed to compare the impact of propofol and sevoflurane on delirium after spine surgery in elderly patients.

Official Title
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Impact of Propofol Versus Sevoflurane on Incidence of Postoperative Delirium in Elderly Patients After Spine Surgery: a Randomized Controlled Trial

Conditions
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Delirium in Old Age, Anaesthetic

Intervention / Treatment
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* Drug: propofol infusion
* Drug: sevoflurane inhalation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age ≥65 years and ≤90 years; scheduled to undergo surgery for spinal, under general anaesthesia; American Society of Anesthesiology (ASA) I-III; agree to participate, and give signed written informed consents. Exclusion Criteria: family history or history of malignant hyperthermia; History of propofol or sevoflurane allergy; demonstrated cognitive impairment on the modified Mini-Mental State Examination (score, <24of 30 or <20 of 30 if the patient's education year was less than 6 years or<17 if the patient is Illiterate); planned postoperative intubation or transferred to ICU; severe visual or auditory handicap; prior diagnoses of neurologic diseases or mental disorders (e.g., stroke, Parkinson's disease, dementia, schizophrenia, or depressive illness) take anticholinergic drugs or other drugs acting on the central nervous system for a long time before operation participating in other clinical studies in recent 3 months

Ages Eligible for Study
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Minimum Age: 65 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: propofol group<br>For patients in the propofol group, anaesthesia will be maintained with propofol infusion(target controlled infusion), of which the target concentration will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be maintained with remifentanil(0.1-0.5ug/(kg.min)), muscle relaxation will be maintained with atracurium(10ug/(kg.min)). Propofol infusion will be stopped at the end of surgery. | Drug: propofol infusion<br>* For patients in the propofol group, anaesthesia will be maintained with propofol infusion(target controlled infusion), of which the target concentration will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be maintained with remifentanil(0.1-0.5ug/(kg.min)), muscle relaxation will be maintained with atracurium(10ug/(kg.min)).Propofol infusion will be stopped at the end of surgery.<br>|
| Other: sevoflurane group<br>For patients in the sevoflurane group, anaesthesia will be maintained with sevoflurane inhalation, of which the concentration will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be maintained with remifentanil(0.1-0.5ug/(kg.min)), muscle relaxation will be maintained with atracurium(10ug/(kg.min)). Sevoflurane inhalation will be stopped at the end of surgery. | Drug: sevoflurane inhalation<br>* For patients in the sevoflurane group, anaesthesia will be maintained with sevoflurane inhalation, of which the concentration will be adjusted to maintain the BIS value between 40 and 60. Analgesia will be maintained with remifentanil(0.1-0.5ug/(kg.min)), muscle relaxation will be maintained with atracurium(10ug/(kg.min)). Sevoflurane inhalation will be stopped at the end of surgery.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of delirium after surgery | Delirium is assessed twice daily (8-10 AM and 6-8 PM ) with the 3 minute diagnostic interview for Confusion Assessment Method.Researchers will review all progress notes and nursing documentation for delirium diagnoses, and a thorough medical record review process using the Chart-based Delirium Identification Instrument. | Between postoperative day 1 to discharge or day 7, whichever came first | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The day of postoperative delirium duration among patients who developed delirium | Date; Delirium is assessed twice daily (8-10 AM and 6-8 PM ) with the 3 minute diagnostic interview for Confusion Assessment Method | Time from first to last delirium-positive day. Between postoperative day 1 to discharge or day 7, whichever came first | 
| The day of total delirium-positive days among patients who developed delirium | Days；Delirium is assessed twice daily (8-10 AM and 6-8 PM ) with the 3 minute diagnostic interview for Confusion Assessment Method | Between postoperative day 1 to discharge or day 7, whichever came first | 
| The types of delirium in patients who developed delirium | Richmond Agitation- Sedation Scale will be assessed in patients who developed delirium.Patients with delirium are classified into three subtypes: hyperactive (Richmond Agitation Sedation Scale score consistently positive, from +1 to +4), hypoactive (Richmond Agitation Sedation Scale score consistently neutral or negative, from -3 to 0), and mixed. | Between postoperative day 1 to discharge or day 7, whichever came first | 
| The intubation time in postanesthesia care unit (PACU) | minutes | From the patient transfered into PACU to tracheal extubation. Within 24 hours after surgery. | 
| The length of stay in in postanesthesia care unit (PACU) | minutes | Within 24 hours after surgery. | 
| Incidence of postoperative shivering in PACU | Postoperative shivering is assessed in PACU with The Crossley and Mahajan Scale. The Crossley and Mahajan Scale (0 No shivering 1 One or more of the following: piloerection, peripheral vasoconstriction, peripheralcyanosis with no other cause, but no muscle activity 2 Visible muscular activity confined to one muscle group 3 Visible muscular activity in more than one muscle 4 Gross muscular activity involving the whole body). | Within 24 hours after surgery. | 
| Postoperative nausea and vomiting | Postoperative nausea and vomiting is assessed in PACU and postoperative days 1-3(twice daily 8-10 AM and 6-8 PM ).Nausea is defined as a subjective,unpleasant sensation associated with awareness of the urge to vomit. Retching is defined as the laboured, spastic, rhythmic contraction of the respiratory muscles without expulsion of the gastric contents.Vomiting is defined as the forceful expulsion of gastric contents from the mouth. Each episode will be recorded as either present or absent. If the patients had nausea, severity will be recorded using the following scale: 1, mild nausea; 2, moderate nausea; 3, severe nausea. If the patients had retching or vomiting, severity of episodes will be recorded using the following scale: 1, one episode; 2, two episodes; 3, three or more episodes | Up to 3 days after surgery | 
| Incidence of emergence agitation(EA) | Emergence agitation(EA) is assessed with Richmond Agitation- Sedation Scale (RASS) .The RASS is divided into 10 levels (range of scores, -5 to +4, with higher scores indicating greater agitation). Patients with RASS score > +1 are evaluated as EA | Emergence agitation will be assessed immediately after extubation. Within 24 hours after surgery. | 
| Intensity of pain within 3 days after surgery | Intensity of pain is assessed twice daily ((8-10 AM and 6-8 PM) with the Visual Analogue Scale ( an 11-point rating scale where 0=no pain and 10=the worst pain ) | Up to 3 days after surgery | 
| Postoperative recovery quality | Postoperative recovery quality is assessed with Quality of Recovery-40 scale（ QoR40）on the first day(6-8 PM) after surgery. | The first day(6-8 PM) after surgery | 
| Length of stay in hospital after surgery | days | Up to 30 days after surgery | 
| The incidence of non-delirium complications within 30 days after surgery | The occurrence of non-delirium complications, which are defined as newly occur medical conditions that are harmful for patients' recovery and require therapeutic intervention | Up to 30 days after surgery | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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delirium, spine surgery, anaesthetic, propofol, sevoflurane