American Society for Enhanced Recovery and Perioperative Quality Initiative Joint Consensus Statement on the Role of Neuromonitoring in Perioperative Outcomes: Electroencephalography

Abstract

Electroencephalographic (EEG) monitoring to indicate brain state during anesthesia has become widely available. It remains unclear whether EEG-guided anesthesia influences perioperative outcomes. The sixth Perioperative Quality Initiative (POQI-6) brought together an international team of multidisciplinary experts from anesthesiology, biomedical engineering, neurology, and surgery to review the current literature and to develop consensus recommendations on the utility of EEG monitoring during anesthesia. We retrieved a total of 1023 articles addressing the use of EEG monitoring during anesthesia and conducted meta-analyses from 15 trials to determine the effect of EEG-guided anesthesia on the rate of unintentional awareness, postoperative delirium, neurocognitive disorder, and long-term mortality after surgery. After considering current evidence, the working group recommends that EEG monitoring should be considered as part of the vital organ monitors to guide anesthetic management. In addition, we encourage anesthesiologists to be knowledgeable in basic EEG interpretation, such as raw waveform, spectrogram, and processed indices, when using these devices. Current evidence suggests that EEG-guided anesthesia reduces the rate of awareness during total intravenous anesthesia and has similar efficacy in preventing awareness as compared with end-tidal anesthetic gas monitoring. There is, however, insufficient evidence to recommend the use of EEG monitoring for preventing postoperative delirium, neurocognitive disorder, or postoperative mortality.

Comparison of Bispectral Index-Guided Individualized Anesthesia with Standard General Anesthesia on Inadequate Emergence and Postoperative Delirium in Elderly Patients Undergoing Esophagectomy: A Retrospective Study at a Single Center

“…In previous studies, PD was associated with deeper anesthesia or burst depression of ECG, and BIS-guided anesthesia reduced the occurrence of PD [ 15 – 18 ]. However, these conclusions were not supported in several recent studies [ 32 , 33 ]. The brain of elderly patients is vulnerable to general anesthetics.…”

Improving perioperative brain health: an expert consensus review of key actions for the perioperative care team

“…Specifically, the use of processed EEG is still controversial; randomised trials which achieved separation of anaesthetic dosing based on protocol-based algorithms have found a difference in the incidence of delirium. 50 Those that did not show separation found no effect. 53,54 There is minimal evidence on longer-term outcomes and intraoperative depth as measured by processed EEG, at least in part because of fewer studies of lower quality.…”

“…These include consensus statements from the American Society of Enhanced Recovery (ASER) on postoperative delirium prevention 17 and on the role of processed EEG monitoring in perioperative outcomes. 50 In addition, major studies such as 'NeuroVision' have highlighted the incidence of covert stroke in older surgical patients, the relationship to subsequent postoperative cognitive decline, and the significant incidence of cognitive decline in patients who did not have a stroke. 51 Evidence is also strengthening for the association of frailty with delirium and the need for preoperative cognitive screening to be linked with frailty screening.…”

Investigating Association between Intraoperative Hypotension and Postoperative Neurocognitive Disorders in Non-Cardiac Surgery: A Comprehensive Review

“…Intraoperative monitoring of brain function is rather limited and encompasses two main techniques, namely brain perfusion assessment with cerebral near-infrared spectroscopy (NIRS) or transcranial Doppler (TCD), and electroencephalography (EEG), bispectral index (BIS), qualitative EEG (i.e., patient state analyzer) or EEG-based entropy [ 61 , 62 , 63 ]. The effects of NIRS monitoring of brain oxygenation for reducing the occurrence of POCD are uncertain and there is also uncertainty as to whether active cerebral NIRS monitoring has an important effect on postoperative delirium [ 63 ].…”

“…Ultrasound-guided neuromonitoring can detect vasospasm, cerebral embolism, assess cerebral perfusion and helps in clinical decisions and early therapeutic interventions [ 62 ]. Current evidence suggests that EEG-guided anesthesia reduces the rate of awareness during total intravenous anesthesia but there is insufficient evidence to recommend it for preventing postoperative delirium or postoperative neurocognitive decline [ 61 ].…”