Management Based on Multimodal Brain Monitoring May Improve Functional Connectivity and Post-operative Neurocognition in Elderly Patients Undergoing Spinal Surgery

Abstract

Perioperative neurocognitive disorder (PND) is a common condition in elderly patients undergoing surgery. Sedation, analgesia, regional cerebral oxygen saturation (rSO2), and body temperature are known to be associated with PND, but few studies have examined the contribution of these factors combined in detail. This prospective, randomized, controlled, double-blinded study investigated whether anesthesia management based on multimodal brain monitoring—an anesthesia management algorithm designed by our group—could improve the post-operative cognitive function and brain functional connectivity (FC) in elderly patients undergoing elective spinal surgery with general anesthesia. The patients (aged ≥65 years) were randomized into two groups [control (Group C), n = 12 and intervention (Group I), n = 14]. Patients in Group I were managed with multimodal brain monitoring (patient state index, spectral edge frequency, analgesia nociception index, rSO2, and temperature), and those in Group C were managed with routine anesthesia management. All patients were pre- and post-operatively evaluated (7 days after surgery) with the Montreal Cognitive Assessment (MoCA). Amplitude of low-frequency fluctuation (ALFF) and FC were analyzed after resting-state functional MRI. Serum C-reactive protein (CRP) and lipopolysaccharide levels were measured, and the correlation between FC and changes in inflammatory marker levels was analyzed. Mean post-operative MoCA score was higher in Group I (24.80 ± 2.09) than in Group C (22.56 ± 2.24) (p = 0.04), with no difference in PND incidence between groups (28.57 vs. 16.67%; p = 0.47). Group I also showed significantly increased ALFF values in several brain regions after surgery (p < 0.05), and FC between the left hippocampus and left orbital inferior frontal gyrus (FG), left middle FG, left superior temporal gyrus, and left precentral gyrus was enhanced (p < 0.05), which was negatively correlated with the change in serum CRP (pre vs. post-intervention) (R = −0.58, p = 0.01). These results suggest that management of elderly patients undergoing surgery by multimodal brain monitoring may improve post-operative neurocognition and FC by reducing systemic inflammation.Clinical Trial Registration:http://www.chictr.org.cn/index.aspx, identifier: ChiCTR1900028024.

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

“…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 . However, the RCT by Meghawry et al 26 randomized the patients according to a hypotension induced protocol for shoulder surgery in beach chair position.…”

“…Postoperative delirium (POD) alone was the primary endpoint in 4 studies 18,21,23,28 . Five studies analyzed postoperative cognitive function as primary endpoint [24][25][26][27]29 . Two studies evaluated postoperative cognitive function as well as POD 7,20 .…”

“…The BIS value was here the studied parameter. Two studies used the Patient State Index (PSI) and the EEG based Density Spectral Analysis (DSA) 23,29 . In one study the authors analyzed bilateral raw EEG and the corresponding DSA provided by the NeuroSENSE ® DOA monitor 7 .…”

“…In 4 studies the raw channel EEG was the used monitor 16,17,19,22 . Only 8 studies used an algorithm to avoid/treat cerebral oxygen desaturation and/or to treat EEG abnormalities, EEG suppression or abnormally low BIS values 7,16,17,20,23,25,27,29 . The double-blind RCT by Xu et al analyzed whether a processed EEG-guided anesthesia management, including PSI combined with DSA monitoring could reduce the incidence of POD in Method (2.4% in the intervention group vs 20% in the control group).…”

“…The small sample sized RCT of Yang et al divided 26 patients undergoing spinal surgery into an intervention group where a multimodal brain management strategy involved EEG-based PSI and DSA together with Analgesia Nociception Index and cerebral oximetry 29 . In the control group the DOA was based on BIS.…”