Effect of Electroencephalography-Guided Anesthetic Administration on Postoperative Delirium Among Older Adults Undergoing Major Surgery: The ENGAGES Randomized Clinical Trial

JAMA. 2019 Feb 5;321(5):473-483. doi: 10.1001/jama.2018.22005.

Abstract

Importance: Intraoperative electroencephalogram (EEG) waveform suppression, often suggesting excessive general anesthesia, has been associated with postoperative delirium.

Objective: To assess whether EEG-guided anesthetic administration decreases the incidence of postoperative delirium.

Design, setting, and participants: Randomized clinical trial of 1232 adults aged 60 years and older undergoing major surgery and receiving general anesthesia at Barnes-Jewish Hospital in St Louis. Recruitment was from January 2015 to May 2018, with follow-up until July 2018.

Interventions: Patients were randomized 1:1 (stratified by cardiac vs noncardiac surgery and positive vs negative recent fall history) to receive EEG-guided anesthetic administration (n = 614) or usual anesthetic care (n = 618).

Main outcomes and measures: The primary outcome was incident delirium during postoperative days 1 through 5. Intraoperative measures included anesthetic concentration, EEG suppression, and hypotension. Adverse events included undesirable intraoperative movement, intraoperative awareness with recall, postoperative nausea and vomiting, medical complications, and death.

Results: Of the 1232 randomized patients (median age, 69 years [range, 60 to 95]; 563 women [45.7%]), 1213 (98.5%) were assessed for the primary outcome. Delirium during postoperative days 1 to 5 occurred in 157 of 604 patients (26.0%) in the guided group and 140 of 609 patients (23.0%) in the usual care group (difference, 3.0% [95% CI, -2.0% to 8.0%]; P = .22). Median end-tidal volatile anesthetic concentration was significantly lower in the guided group than the usual care group (0.69 vs 0.80 minimum alveolar concentration; difference, -0.11 [95% CI, -0.13 to -0.10), and median cumulative time with EEG suppression was significantly less (7 vs 13 minutes; difference, -6.0 [95% CI, -9.9 to -2.1]). There was no significant difference between groups in the median cumulative time with mean arterial pressure below 60 mm Hg (7 vs 7 minutes; difference, 0.0 [95% CI, -1.7 to 1.7]). Undesirable movement occurred in 137 patients (22.3%) in the guided and 95 (15.4%) in the usual care group. No patients reported intraoperative awareness. Postoperative nausea and vomiting was reported in 48 patients (7.8%) in the guided and 55 patients (8.9%) in the usual care group. Serious adverse events were reported in 124 patients (20.2%) in the guided and 130 (21.0%) in the usual care group. Within 30 days of surgery, 4 patients (0.65%) in the guided group and 19 (3.07%) in the usual care group died.

Conclusions and relevance: Among older adults undergoing major surgery, EEG-guided anesthetic administration, compared with usual care, did not decrease the incidence of postoperative delirium. This finding does not support the use of EEG-guided anesthetic administration for this indication.

Trial registration: ClinicalTrials.gov Identifier: NCT02241655.

Publication types

  • Comparative Study
  • Pragmatic Clinical Trial
  • Randomized Controlled Trial
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Aged, 80 and over
  • Algorithms
  • Anesthesia, General / adverse effects
  • Anesthetics, General / administration & dosage*
  • Anesthetics, General / adverse effects
  • Cardiotonic Agents / therapeutic use
  • Electroencephalography*
  • Emergence Delirium / epidemiology
  • Emergence Delirium / prevention & control*
  • Female
  • Humans
  • Hypotension / chemically induced
  • Hypotension / drug therapy
  • Incidence
  • Intraoperative Complications / chemically induced
  • Male
  • Middle Aged
  • Monitoring, Intraoperative / methods*
  • Phenylephrine / therapeutic use
  • Postoperative Nausea and Vomiting
  • Surgical Procedures, Operative / adverse effects
  • Surgical Procedures, Operative / mortality

Substances

  • Anesthetics, General
  • Cardiotonic Agents
  • Phenylephrine

Associated data

  • ClinicalTrials.gov/NCT02241655