Anesthesia Depth Increases the Degree of Postoperative Dementia, Delirium, and Cognitive Dysfunction (BIS & Dementia)

Anesthesia Depth Increases the Degree of Postoperative Dementia, Delirium, and Cognitive Dysfunction by a Higher Load of Neurotrophic Drugs

Anesthetics and anesthesia are suspicious to induce dementia or aggravate preexistent cognitive deficits with or without evoking postoperative delirium. In animal trials various anesthetics induce increased levels of misfolded amyloid beta and protein tau, the molecular substance of pathophysiologic brain tissues of demented patients. The amount of those markers seems to correlate well with the degree of dementia [1]. In contradiction, a single study indicates that the incidence of postoperative cognitive deficit (POCD) decreases if hypnotic depth is deep [2]. Unfortunately the study did not sum up the amount of anesthetic drug load, since this would have clarified if the amount of anesthetics used is associated to POCD and dementia. Another possibility is that stress and noxious stimulation induced by light anesthesia results in POCD, whereas deep anesthesia protects from it or inhibits implicit memory.

The investigators' prospective randomized trial is underway to verify the impact of anesthetics and narcotic depth upon grade of dementia and incidence of early postoperative cognitive dysfunction on postoperative day 1 as well as the incidence of delirium within a 90 day period.

The investigators' hypothesis is that the incidence of POCD and delirium and the degree of early cognitive dysfunction is less when anesthetic and vasoactive drug load is less in the BIS- guided anesthesia group with the superficial but sufficient anesthesia level.

Study Overview

• Status: Completed
• Conditions: Delirium; Dementia; Anesthesia; Bispectral Index Monitor
• Intervention / Treatment: Device: Anesthesia depth monitor; Drug: propofol and sevoflurane; Device: Sham control

• Study Type: Interventional
• Enrollment (Actual): 138
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Germany
  • BW
    • Mannheim, BW, Germany, 69163
      • Diakonissen Hospital

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 16 years to 108 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• adults older than 70 years
• major surgery ( spine, orthopedic, urologic, gynecology, abdominal)

Exclusion Criteria:

• adults younger than 71 years
• major blood loss surgery
• allergy to soja oil, nuts, other ingredients of propofol
• patient wants to have spinal or regional anesthesia only

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Anesthesia depth monitor; Anesthesia depth is aimed to be between BIS 50-60	Device: Anesthesia depth monitor; Other Names: Aim at an anesthesia level of BIS 50-60 titrating propofol and sevoflurane in the experimental; Drug: propofol and sevoflurane
Sham Comparator: Control group; Anesthesia depth is monitored but blinded to the anesthesiologist	Drug: propofol and sevoflurane; Device: Sham control; Standard care as usual. Bis m Standard care as usual. Bispectral index monitor is not visible for anesthesia provider.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative cognition and mental capacity of elderlies following major surgery	Mini Mental State Test (MMSE) and automated Memory and Attention Test (MAT) were performed on the day before and after the surgery. The MAT is a validated computerized test for the discrimination of short and long time memory, for visual and auditory comprehension and attention capacity.	One day after surgery

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of mental and other complications (serious adverse events)	Incidences of delirium and mental dysfunction until hospital discharge is counted. Delirium was postoperatively diagnosed by the NUDESC, postoperative cognitive dysfunction (POCD) by the MAT, other serious adverse events in the course of the hospital stay were noted.	90 postoperative days

Collaborators and Investigators

• Sponsor: Heidelberg University
• Investigators: Study Director: Thomas Frietsch, Prof, MD, Universitätsmedizin Mannheim

Study record dates

Study Major Dates

• Study Start: January 1, 2014
• Primary Completion (Actual): May 8, 2017
• Study Completion (Actual): May 8, 2017

Study Registration Dates

• First Submitted: August 11, 2014
• First Submitted That Met QC Criteria: March 5, 2015
• First Posted (Estimate): March 6, 2015

Study Record Updates

• Last Update Posted (Actual): May 24, 2022
• Last Update Submitted That Met QC Criteria: May 17, 2022
• Last Verified: May 1, 2022

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Brain Diseases; Central Nervous System Diseases; Nervous System Diseases; Neurologic Manifestations; Confusion; Neurobehavioral Manifestations; Neurocognitive Disorders; Cognition Disorders; Delirium; Dementia; Cognitive Dysfunction; Physiological Effects of Drugs; Central Nervous System Depressants; Anesthetics, Intravenous; Anesthetics, General; Platelet Aggregation Inhibitors; Hypnotics and Sedatives; Anesthetics, Inhalation; Anesthetics; Propofol; Sevoflurane
• Other Study ID Numbers: BIS-Diako-Ma-2014