Use of Brain Wave Monitoring During Surgery to Reduce Postoperative Cognitive Dysfunction

The Role of Brain Wave Monitoring in Reducing the Incidence of Postoperative Cognitive Dysfunction

This research study is being done to determine if indices derived from monitoring brain wave activity while under general anesthesia will predict the likelihood of post-operative cognitive dysfunction in patients over 60 years old.

Study Overview

• Status: Recruiting
• Conditions: Postoperative Cognitive Dysfunction

Detailed Description

Postoperative cognitive dysfunction (POCD) occurs in 30-40% of older adults after undergoing surgical procedures. POCD be subtle, such as a formerly avid reader unable to read for comprehension, to more overt, such as the inability to perform self-care. This deterioration in cognitive function leads to increased mortality, premature departure from the labor market and economic hardship. With 25 million people over the age of 60 undergoing surgical procedures annually in the United States and most of them living long into their 8th decade, prevention of POCD is an important public health issue.

The causal mechanism of POCD remains unclear, though older patients who receive general anesthesia are at increased risk relative to younger patients. While the association between age and POCD is not fully understood, several normal, age-related changes to brain anatomy and physiology may explain the increased susceptibility. These include decreased brain volume, notably in the prefrontal cortex, cortical thinning and altered neurotransmitter function. Taken together, these changes decrease the anesthetic requirements for older patients to achieve a similar anesthetic state and make them susceptible to overdosing of anesthetic agents. This is supported by studies using electroencephalography (EEG) to measure cerebral cortical activity which have demonstrated profound age-related differences for patients receiving general anesthesia. Older patients are more likely to develop burst suppression, an EEG pattern associated with an excessive anesthetic state. Currently, a major limitation in the field is the absence of studies that have used raw EEG data to examine the association between the dosing of anesthetic agents and POCD in older patients. Although prior studies have used EEG-derived depth of anesthesia indices to explore this association, these indices have been shown to be an unreliable measure of anesthetic state in older patients. Thus, the question of whether an excessive anesthetic state in this population causes POCD remains unanswered.

The investigators will recruit 100 adults over 60 years of age who undergo elective surgery under general anesthesia with EEG monitoring. A brief neurocognitive test battery will be conducted before surgery, 3-7 day post-surgery, and 3 months post-surgery to assess the association between EEG suppression and POCD.

In this study, the investigators hypothesize that the duration of EEG suppression is associated with POCD.

• Study Type: Observational
• Enrollment (Estimated): 100

Contacts and Locations

• Study Contact: Name: M. Dustin Boone, MD; Phone Number: 603-650-5922; Email: myles.d.boone@hitchcock.org
• Study Contact Backup: Name: Crystallee J Newton, BA; Phone Number: 603-653-0495; Email: Crystallee.J.Newton@Hitchcock.org

Study Locations

• United States
  • New Hampshire
    • Lebanon, New Hampshire, United States, 03756
      • Recruiting
      • Dartmouth-Hitchcock Medical Center
      • Contact: Crystallee J Newton, BA; Phone Number: 603-653-0495; Email: Crystallee.J.Newton@Hitchcock.org
      • Contact: Sean G Dabney; Phone Number: 603-653-3337; Email: Sean.G.Dabney@hitchcock.org

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 60 years to 80 years (Adult, Older Adult)
• Accepts Healthy Volunteers: Yes

• Sampling Method: Non-Probability Sample

Study Population

60-80 years of age who present for elective, non-cardiac surgical procedure requiring general anesthesia and an anticipated two-day or longer inpatient hospital stay

Description

Inclusion Criteria:

• 60-80 years of age who present for elective, non-cardiac surgical procedure requiring general anesthesia and an anticipated two-day or longer inpatient hospital stay
• English as the native and primary language
• Presence of an informant who has had weekly contact with the participant for at least the last year
• Participant is capable of providing written informed consent.

Exclusion Criteria:

• history of persistent and severe mental illness (e.g., schizophrenia, bipolar disorder)
• neurological disorder (e.g., Parkinson's disease, epilepsy, stroke)
• active substance use disorder as defined by the Diagnostic and Statistical Manual Diploma in Social Medicine(DSM-V)
• history of prior diagnosis of learning disability per the DSM-V
• estimated premorbid intellectual functioning below a scaled score of 70 based on the Test of Premorbid Functioning (TOPF)
• severe visual or hearing impairments that prevent the participant from undergoing the neurocognitive assessment.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Cognitive Decline	The investigators will use a Composite Cognitive Change Score (between baseline and 3 months) to determine POCD	3 months postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Effective and Functional Connectivity	The investigators will use a multi-channel EEG (standard 10-20 montage) to assess changes to effective and functional connectivity during general anesethesia	Day of surgery

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative Delirium	The investigators will use CAM-ICU to screen for postoperative delirium	Postoperative days 2-7

Collaborators and Investigators

• Sponsor: Dartmouth-Hitchcock Medical Center
• Investigators: Principal Investigator: M. Dustin Boone, MD, Dartmouth-Hitchcock Medical Center

Publications and helpful links

General Publications

• Monk TG, Weldon BC, Garvan CW, Dede DE, van der Aa MT, Heilman KM, Gravenstein JS. Predictors of cognitive dysfunction after major noncardiac surgery. Anesthesiology. 2008 Jan;108(1):18-30. doi: 10.1097/01.anes.0000296071.19434.1e.
• Purdon PL, Pavone KJ, Akeju O, Smith AC, Sampson AL, Lee J, Zhou DW, Solt K, Brown EN. The Ageing Brain: Age-dependent changes in the electroencephalogram during propofol and sevoflurane general anaesthesia. Br J Anaesth. 2015 Jul;115 Suppl 1(Suppl 1):i46-i57. doi: 10.1093/bja/aev213.
• Morrison JH, Baxter MG. The ageing cortical synapse: hallmarks and implications for cognitive decline. Nat Rev Neurosci. 2012 Mar 7;13(4):240-50. doi: 10.1038/nrn3200.
• Steinmetz J, Christensen KB, Lund T, Lohse N, Rasmussen LS; ISPOCD Group. Long-term consequences of postoperative cognitive dysfunction. Anesthesiology. 2009 Mar;110(3):548-55. doi: 10.1097/ALN.0b013e318195b569.
• Peters R. Ageing and the brain. Postgrad Med J. 2006 Feb;82(964):84-8. doi: 10.1136/pgmj.2005.036665.
• Brown EN, Purdon PL. The aging brain and anesthesia. Curr Opin Anaesthesiol. 2013 Aug;26(4):414-9. doi: 10.1097/ACO.0b013e328362d183.
• Deiner S, Westlake B, Dutton RP. Patterns of surgical care and complications in elderly adults. J Am Geriatr Soc. 2014 May;62(5):829-35. doi: 10.1111/jgs.12794. Epub 2014 Apr 14.

Helpful Links

• CDC

Study record dates

Study Major Dates

• Study Start (Actual): January 24, 2020
• Primary Completion (Estimated): January 1, 2025
• Study Completion (Estimated): January 1, 2025

Study Registration Dates

• First Submitted: December 3, 2019
• First Submitted That Met QC Criteria: December 4, 2019
• First Posted (Actual): December 6, 2019

Study Record Updates

• Last Update Posted (Actual): February 16, 2024
• Last Update Submitted That Met QC Criteria: February 15, 2024
• Last Verified: February 1, 2024

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Mental Disorders; Pathologic Processes; Postoperative Complications; Neurocognitive Disorders; Cognition Disorders; Cognitive Dysfunction; Postoperative Cognitive Complications
• Other Study ID Numbers: D19171

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No