Aging, Anesthesia Brain Monitor, Anesthesia Depth Monitoring, Blood-Brain Barrier Permeability, Inflammaging, Inflammation, Inflammation Biomarkers, Monocyte
Conditions
Keywords
Aging, Inflammation, General Anesthesia, Anesthetic Sensitivity, Cytokines, Alpha Oscillations, Blood Brain Barrier, Monocyte phenotype, macrophage phenotype
Brief summary
The goal of this observational study is to determine whether macrophage/monocyte mediated inflammatory signaling contributes to reduced anesthetic requirements in older adults undergoing major abdominal surgery. The main questions it aims to answer are: * Is there a difference in anesthetic dosing requirements (minimum effective dose) between young and older patients undergoing major abdominal surgery? * How do electroencephalographic (EEG) signatures under anesthesia correlate with age and systemic inflammatory markers? * Is there an association between age, levels of circulating inflammatory cytokines, and monocyte/macrophage phenotypes with anesthetic requirements? If there is a comparison group: Researchers will compare older adult patients undergoing major abdominal surgery to younger adult patients undergoing major abdominal surgery to see if macrophage/monocyte-mediated inflammatory signaling influences anesthetic sensitivity and the risk of postoperative neurocognitive complications in the older population. Participants will: * Receive general anesthesia for major abdominal surgery, with continuous recording of anesthetic dose requirements. * Undergo electroencephalographic (EEG) monitoring during the anesthetic period. * Provide blood samples for the measurement of circulating inflammatory cytokines and the assessment of monocyte phenotypes. * Provide peritoneal tissue samples (collected during surgery) to evaluate tissue macrophage populations. * Provide cerebrospinal fluid (CSF) samples to assess biomarkers of blood-brain barrier permeability.
Interventions
None listed
Sponsors
University of Chile
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age between 18-30 years or over 60 years old * Scheduled for abdominal surgery * General anesthesia planned with or without spinal anesthesia * Able and willing to provide written informed consent.
Exclusion criteria
* Chemotherapy or systemic corticosteroid use within the past 2 weeks. * Pregnancy. * Active sepsis or systemic infection. * Emergency surgery. * Requirement of ketamine or dexmedetomidine during the first hour of anesthesia. * History or diagnosis of: stroke with persistent neurological deficit, dementia, Alzheimer's disease, Huntington's disease, amyotrophic lateral sclerosis, central nervous system autoimmune disorders, systemic autoimmune diseases, or infectious diseases of the central nervous system. * Current treatment with immunomodulatory medications. * Psychiatric disorders with psychotic features. * Use of psychoactive or psychotropic recreational drugs within the week prior to surgery.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Frontal EEG alpha-band power | Perioperative | Relative EEG alpha power during surgery under general anesthesia guided by standard age-adjusted dosing |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Time-to-loss of consciousness | Perioperative | During propofol slow induction, the time required for unresponsiveness to verbal stimuli |
| Intraoperative anesthetic requirements | Perioperative | Total dose and infusion rate of propofol and/or sevoflurane adjusted using frontal EEG monitoring |
| Time to emergence | Perioperative | Time in minutes to eye opening since end of anesthesia, with verbal stimuli. |
| Cytokine circulating profile | Baseline | Serum inflammatory cytokine profile |
| Monocyte/Macrophage phenotype in blood and peritoneal samples | Periprocedural | inflammatory cell Pheontype present in circulating blood (monocytes) and in peritoneal lavage and tissue samples. |
| Blood-brain barrier permeability | Baseline | CSF biomarkers present: albumin, cytokines. |
Countries
Chile
Contacts
CONTACTCatalina Andrea Díaz Papapietro, Anesthesiologist, MD PhD (c)
CONTACTRodrigo Gutiérrez Rojas, Assitant Professor, MD PhD
STUDY_CHAIRAntonello Penna Silva, Anesthesia Professor, MD PhD
Brain and Anesthesia Laboratory (BAL), University of Chile
Outcome results
None listed