The Impact of Multimodal Brain Monitoring on Postoperative Outcomes in Elderly Patients Undergoing Major Abdominal Surgery

Official title

Impact of Multimodal Brain Monitoring Under General Anesthesia on Postoperative Outcomes in Elderly Patients Undergoing Major Abdominal Surgery: A Multicenter, Prospective, Single-blind, Randomized Controlled Study

Overview

The purpose of this clinical trial is to investigate the effect of multimodal brain monitoring under general anesthesia on postoperative outcomes in elderly patients undergoing abdominal surgery.The research hypothesis is that multimodal brain monitoring under general anesthesia can reduce the incidence of postoperative composite complications and improve postoperative outcomes in elderly patients undergoing major abdominal surgery. Eligible patients will be randomly assigned in a 1:1 ratio to the Multimodal Brain Monitoring under General Anesthesia Group (MBMGA group) and the Bispectral Index Monitoring under General Anesthesia Group (BIS group). The primary outcome is the postoperative composite complication rate . Secondary outcomes include intraoperative hyperglycemia, adverse events during anesthesia induction and maintanance, changes in blood pressure and heart rate, intraoperative hypotension, the dosage of perioperative anesthetics and vasoactive drugs, changes in serum cortisol, cardiac troponin I, blood creatinine (Cr) level, extubation time and awake time, the rate of transferring to ICU or AICU, The time to first use analgesia pump and the cumulative dose of postoperative oxycodone, systemic complications, hospitalization time, first exhaust time , first oral intake time, rate of second surgery and mortality within 30 days postoperatively. Participants will: 1. Undergo routine preoperative fasting for 6-8 hours; 2. Prior to anesthesia induction, cooperate with the establishment of intravenous access, arterial catheterization, monitoring of physiological parameters, blood sample collection, and receive fluid preloading; 3. During surgery, for patients in the MBMGA group , propofol and remifentanyl will be adjusted according to multimodal brain monitoring indices (WLi and PTi), while for patients in the BIS group, only propofol will be adjusted based on bispectral index and remifentanyl will be adjusted according to anesthesiologists' experience; simultaneously, vital signs, including respiration, body temperature, fluid therapy, blood pressure, and heart rate regulation, will be monitored and managed. 4. After surgery, endotracheal tubes will be removed once extubation criteria are met, and patients will be transferred to the PACU, where they will receive routine monitoring and will be discharged from the PACU upon meeting corresponding scoring criteria; 5. Participates in follow-ups on the day of surgery and for 1-30 days postoperatively, during which investigators will record the primary outcome and secondary outcomes.

Interventions

• Other Multimodal brain monitoring guided anesthesia
  During the anesthesia induction phase, the dosage administration is guided by the goal of reducing PTi to the range of 40-70, and tracheal intubation is performed when both PTi and WLI are within 40-70. In the anesthesia maintenance phase, the propofol dosage is adjusted according to the WLI value to maintain WLI within 40-70, while the remifentanil dosage is adjusted based on the PTi value to keep PTi within 40-70. In the event of sudden increased intraoperative pain stimulation (PTi \> 70) acc
• Other Bispectral Index(BIS) monitoring guided anesthesia
  During the anesthesia induction phase, the dosage administration is guided by the goal of reducing BIS to the range of 40-60, with remifentanil supplemented based on clinical experience. In the anesthesia maintenance phase, the propofol dosage is adjusted according to BIS values to maintain BIS within 40-60, while the remifentanil dosage is adjusted based on anesthesiologists' experience. When there is a high suspicion of sudden tachycardia and hypertension induced by increased intraoperative pa

Primary outcome measures

• Incidence of Postoperative Composite Complication [Time frame: From post-extubation to postoperative Day 30]

Secondary outcome measures (12)

• Incidence of intraoperative stress-induced hyperglycemia [Time frame: From anesthesia induction to skin closure, assessed up to 5 minutes after surgery]
• Incidence of intraoperative composite adverse events [Time frame: during operation, assessed up to 5 minutes after surgery]
• Blood pressure change immediately after intubation [Time frame: at anesthesia induction and immediately after intubation, assessed up to 10 seconds after intubation]
• Duration of intraoperative hypotension [Time frame: From the anesthesia induction to the end of surgery, assesed up to 5 minutes after surgery]
• Total pintraoperative anesthetic/vasoactive drug dosages [Time frame: from the anesthesia induction to the end of surgery, assessed up to 5 minutes after surgery]
• Serum cortisol levels before surgery and 24 hours postoperatively [Time frame: From before surgery and 24 hours post-operation]
• Durations from drug cessation to awake/extubation [Time frame: From drug cessation to awake/extubation , assessed up to 2 hours after entering post-anesthsia care unit]
• Rate of postoperative Intensive Care Unit/Anesthesia Intensive Care Unit transfer [Time frame: From the end of surgery to Discharge, assessed up to 2 weeks after surgery]
• Duration to first patient controlled intravenous analgesia pump use [Time frame: From the initiation of patient controlled intravenous analgesia pump use to the discontinuation of analgesic pump use, assessed up to 3 days after surgery]
• Incidence of complications in other organ systems during the follow-up period except stress induced hyperglycemia [Time frame: From the start of surgery to 30 days post-operation]
• Length of hospital stay [Time frame: From patient admission to discharge, assessed up to 2 weeks after surgery]
• Rate of second operation [Time frame: From immediately after surgery to 30 days postoperatively]

Eligibility criteria

Inclusion criteria

Aged ≥65 years, regardless of gender; Scheduled for elective abdominal surgery with general anesthesia duration (from anesthesia induction to surgery completion) ≥ 2 hours; American Society of Anesthesiologists (ASA) physical status classification of I-III; Body mass index (BMI) of 18.5-29.9 kg/m²; Postoperative hospital stay expected to exceed 72 hours; Compliant with ethical standards, with voluntary signed informed consent.

Exclusion criteria

Severe cardiovascular diseases, including:

History of myocardial infarction within the past 6 months; Bradycardia (resting heart rate <50 beats/min); Uncontrolled hypertension (sitting systolic blood pressure ≥160 mmHg and/or diastolic blood pressure ≥100 mmHg during screening); Sitting systolic blood pressure ≤90 mmHg during screening; History of severe valvular heart disease; Uncontrolled severe respiratory infections: e.g., severe pneumonia, acute bronchitis.

Abnormal liver function: Aspartate Aminotransferase (AST) and/or Alanine Aminotransferase (ALT) ≥2.5×Upper Limit of Normal (ULN), Total Bilirubin (TBIL) ≥1.5×Upper Limit of Normal (ULN); Abnormal renal function: urea or blood urea nitrogen (BUN) ≥1.5×Upper Limit of Normal (ULN), serum creatinine >Upper Limit of Normal (ULN); Admission hemoglobin A1c (HbA1c) ≥6.5% or ≥2 fasting blood glucose measurements ≥180 mg/dl (10 mmol/L) and/or random blood glucose ≥200 mg/dL (≈11.1 mmol/L); Preoperative anemia (Hemoglobin \[Hb\] ≤90 g/L), thrombocytopenia (Platelet \[PLT\] ≤80×10⁹/L), hypoproteinemia (Albumin \[Alb\] ≤30 g/L); History of drug abuse and/or alcoholism within the past 2 years (alcoholism defined as daily average alcohol consumption >2 units, where 1 unit = 360 mL beer or 45 mL 40% ethanol liquor or 150 mL wine); Neurological diseases (e.g., stroke within 6 months, Alzheimer's disease, Parkinson's disease, mental disease, myasthenia gravis) or psychiatric disorders (e.g., schizophrenia, mania, bipolar disorder, delirium), history of long-term use of neuropsychiatric medications, or cognitive impairment; Allergy or contraindication to study medications; Patients refusing or unable to cooperate with the study; Scheduled for pancreatic surgery; Other conditions deemed inappropriate for participation by the investigator.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Prevention

Study locations

China · 4 centers

• Xuanwu Hospital Capital Medical University — Beijing
• Peking University International Hospital — Beijing
• The First Affiliated Hospital of Zhengzhou University — Zhengzhou
• Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology — Wuhan

Publications

• American Diabetes Association Professional Practice Committee. 16. Diabetes Care in the Hospital: Standards of Care in Diabetes-2025. Diabetes Care. 2025 Jan 1;48(1 Suppl 1):S321-S334. doi: 10.2337/dc25-S016. PMID 39651972
• You J, Chen X, Rong Y, Pan S, Liu T, Xie Y. Application value of different frailty assessment tools in older patients undergoing major abdominal surgery. Exp Gerontol. 2025 Oct 1;209:112852. doi: 10.1016/j.exger.2025.112852. Epub 2025 Jul 29. PMID 40744366
• Trocheris-Fumery O, Flet T, Scetbon C, Tarpin P, Meynier J, Badaoui R, De Broca B, Sabbagh C, Regimbeau JM, De Sousa P, Foulon A, Josse E, Dupont H, Bar S, Abou-Arab O. Early Use of Norepinephrine in High-risk Patients Undergoing Major Abdominal Surgery: A Randomized Controlled Trial. Anesthesiology. 2025 Nov 1;143(5):1160-1170. doi: 10.1097/ALN.0000000000005704. Epub 2025 Aug 4. PMID 40758953
• Zhang Y, Yan R, Kurexi A, Yuan T, Taati Z, Mijiti M, Li D, Wei F. The relationship between preoperative SPPB scores and 30-day postoperative pulmonary complications in elderly patients undergoing elective major abdominal surgery. BMC Surg. 2025 Oct 28;25(1):507. doi: 10.1186/s12893-025-03260-6. PMID 41152837
• Bieze M, McGinn R, Berrio-Valencia M, Talarico R, Martel G, McCluskey SA, McIsaac DI. Temporal trends in postoperative outcomes after major abdominal surgery: a population-based cohort study. Br J Anaesth. 2026 Jan;136(1):237-246. doi: 10.1016/j.bja.2025.08.030. Epub 2025 Oct 23. PMID 41136320
• Gameiro J, Neves JB, Rodrigues N, Bekerman C, Melo MJ, Pereira M, Teixeira C, Mendes I, Jorge S, Rosa R, Lopes JA. Acute kidney injury, long-term renal function and mortality in patients undergoing major abdominal surgery: a cohort analysis. Clin Kidney J. 2016 Apr;9(2):192-200. doi: 10.1093/ckj/sfv144. Epub 2016 Jan 18. PMID 26985368
• Teixeira C, Rosa R, Rodrigues N, Mendes I, Peixoto L, Dias S, Melo MJ, Pereira M, Bicha Castelo H, Lopes JA. Acute kidney injury after major abdominal surgery: a retrospective cohort analysis. Crit Care Res Pract. 2014;2014:132175. doi: 10.1155/2014/132175. Epub 2014 Feb 24. PMID 24719758
• Zhang W, Cheng Y, Zhang L, Wei Y, Xie H, Huang J. Association between emergence delirium and brain status parameters in children undergoing general anesthesia: A prospective observational study. Paediatr Anaesth. 2024 Feb;34(2):130-137. doi: 10.1111/pan.14779. Epub 2023 Oct 3. PMID 37788105

Identifiers

NCT: NCT07713355 · Linyanshen[2025]075-004-xz-1

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗