Processed Multiparameter Electroencephalogram-Guided General Anesthesia Management Can Reduce Postoperative Delirium Following Carotid Endarterectomy: A Randomized Clinical Trial

Abstract

Background: Patients undergoing carotid endarterectomy (CEA) for severe carotid stenosis are vulnerable to postoperative delirium, a complication frequently associated with poor outcome. This study investigated the impact of processed electroencephalogram (EEG)-guided anesthesia management on the incidence of postoperative delirium in patients undergoing CEA.Methods: This single-center, prospective, randomized clinical trial on 255 patients receiving CEA under general anesthesia compared the outcomes of patient state index (PSI) monitoring [SEDLine Brain Function Monitor (Masimo, Inc, Irvine, CA)] (standard group, n = 128) with PSI combined with density spectral array(DSA) -guided monitoring (intervention group, n = 127) to reduce the risk of intraoperative EEG burst suppression. All patients were monitored by continuous transcranial Doppler ultrasound (TCD) and near-infrared spectroscopy (NIRS) to avoid perioperative cerebral hypoperfusion or hyperperfusion. According to the surgical process, EEG suppression time was calculated separately for three stages: S1 (from anesthesia induction to carotid artery clamping), S2 (from clamping to declamping), and S3 (from declamping to the end of surgery). The primary outcome was incidence of postoperative delirium according to the Confusion Assessment Method algorithm during the first 3 days post-surgery, and secondary outcomes were other neurologic complications and length of hospital stay.Results: There were no episodes of cerebral hypoperfusion or hyperperfusion according to TCD and NIRS monitoring in either group during surgery. The incidence of postoperative delirium within 3 days post-surgery was significantly lower in the intervention group than the standard group (7.87 vs. 28.91%, P < 0.01). In the intervention group, the total EEG suppression time and the EEG suppression time during S2 and S3 were shorter (Total, 0 “0” vs. 0 “1.17” min, P = 0.04; S2, 0 “0” vs. 0 “0.1” min, P < 0.01; S3, 0 “0” vs. 0 “0” min, P = 0.02). There were no group differences in incidence of neurologic complications and length of postoperative hospital stay.Conclusion: Processed electroencephalogram-guided general anesthesia management, consisting of PSI combined with DSA monitoring, can significantly reduce the risk of postoperative delirium in patients undergoing CEA. Patients, especially those exhibiting hemodynamic fluctuations or receiving surgical procedures that disrupt cerebral perfusion, may benefit from the monitoring of multiple EEG parameters during surgery.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT03622515.

Desflurane is risk factor for postoperative delirium in older patients’ independent from intraoperative burst suppression duration

“…POD is the most frequent brain dysfunction seen after anesthesia procedures, most frequently occurring in elderly patients, where prolonged periods of too deep anesthesia are a known risk factor. It is today common sense, that EEG guidance of depth of anesthesia can reduce the risk to develop POD in elderly patients ( Chan et al, 2013 ; Radtke et al, 2013 ; Whitlock et al, 2014 ; Punjasawadwong et al, 2018 ; Chan et al, 2020 ; Sumner et al, 2022 ) by avoiding too deep anesthesia ( Evered et al, 2021 ) and prolonged periods of burst suppression ( Soehle et al, 2015 ; Fritz et al, 2016 ; Xu et al, 2021 ). However, in recent years some randomised control trials failed to prove the advantage of EEG guidance ( Zhou et al, 2018 ; Wildes et al, 2019 ; Tang et al, 2020 ; Wang et al, 2022 ).…”

Effect of combined use of cerebral oximetry and electroencephalogram monitoring on the incidence of perioperative neurocognitive disorders in adult cardiac and non-cardiac surgery: A systematic review of randomized and non-randomized trials

“…Table II shows the characteristics of the included studies. The included studies analyzed patients undergoing cardiac surgery (N = 7) 7,[16][17][18][19][20][21] , carotid surgery (N = 2) 22,23 , shoulder surgery in beach chair position (N = 3) [24][25][26] and other non-cardiac interventions (N = 3) 27,28 . Among the 15 included studies, two were retrospective 16,17 , eight were prospective 7,18,19,21,22,24,25,28 and five were a randomized controlled trial (RCT) 20,23,26,27,29 .…”

Geriatric Considerations

“…18 Despite the variable evidence of value of EEG monitoring, there are ongoing trials in this area; a recent smaller study suggested that processed EEG may have efficacy in reducing postoperative delirium in certain types of surgery. 19 Until more definitive larger studies are available, the clinical value of using processed EEG to reduce the occurrence of postoperative delirium through a reduction in burst suppression, particularly those with preoperative cognitive impairment, remains to be determined. 20…”