The Effects of Bispectral Index-Guided Anesthesia on Postoperative Delirium in Elderly Patients: A Systematic Review and Meta-Analysis

World Neurosurg. 2021 Mar:147:e57-e62. doi: 10.1016/j.wneu.2020.11.110. Epub 2020 Dec 9.

Abstract

Objective: Postoperative delirium (POD) is a form of delirium that affects patients who have undergone surgical procedures and anesthesia, usually peaking between 1 and 3 days after their operation. The aim of this meta-analysis was to determine whether monitoring of depth of anesthesia may influence the incidence of POD.

Methods: A systematic literature search was conducted on studies that reported POD in elderly patients (>60 years old) who underwent surgery. This meta-analysis was carried out using random-effects model.

Results: Compared with control group, intraoperative bispectral index (BIS) monitoring reduced POD (odds ratio 1.32, 95% confidence interval 1.11-1.57, P = 0.001, I2 = 51%). In the mixed-surgery group, compared with the control group, BIS monitoring decreased the incidence of POD (odds ratio 1.24, 95% confidence interval 1.07-1.44, P = 0.004, I2 = 61%). There was also no significant difference in the incidence of POD among patients who underwent cardiac, colon, and orthopedic surgeries.

Conclusions: BIS monitoring during surgery can reduce the incidence of POD in elderly patients. Whether BIS monitoring may reduce the incidence of POD in a single type of surgery needs further study.

Keywords: Bispectral index; Elderly patients; Major surgery; Postoperative delirium.

Publication types

  • Meta-Analysis
  • Systematic Review

MeSH terms

  • Aged
  • Aged, 80 and over
  • Anesthesia / methods*
  • Consciousness Monitors*
  • Delirium / epidemiology
  • Emergence Delirium / epidemiology*
  • Humans
  • Incidence
  • Middle Aged
  • Monitoring, Intraoperative / methods*
  • Postoperative Complications / epidemiology
  • Randomized Controlled Trials as Topic