Obesity (BMI>30), Postoperative Cognitive Function
Conditions
Keywords
Obesity, Cognitive Function, Mini-Mental State Examination, MMSE, Sevoflurane, Total Intravenous Anesthesia, TIVA, Low-Flow Anesthesia, BIS Monitoring, Laparoscopic Surgery
Brief summary
Obese patients are at increased risk of postoperative cognitive dysfunction (POCD). The effects of different anesthetic techniques on postoperative cognitive function remain controversial. This prospective randomized study aimed to compare the effects of low-flow sevoflurane anesthesia, normal-flow sevoflurane anesthesia, and total intravenous anesthesia (TIVA) on postoperative cognitive function and recovery characteristics in obese patients undergoing elective laparoscopic abdominal surgery. Cognitive function was assessed using the Mini-Mental State Examination (MMSE) before surgery, at postoperative 30 minutes, and on postoperative day 3.
Detailed description
Obesity is associated with physiological alterations that may increase the risk of postoperative cognitive dysfunction (POCD). The influence of anesthetic techniques on postoperative cognitive outcomes in obese patients remains uncertain. This prospective randomized study was conducted in obese patients (BMI ≥30 kg/m²) aged 18-65 years undergoing elective laparoscopic abdominal surgery under general anesthesia. Patients were randomly assigned to one of three groups: low-flow sevoflurane anesthesia, normal-flow sevoflurane anesthesia, or total intravenous anesthesia (TIVA). Anesthetic depth was monitored using bispectral index (BIS) monitoring and maintained between 40 and 60 in all groups. The primary objective was to compare postoperative cognitive function among the three anesthetic techniques using the Mini-Mental State Examination (MMSE). MMSE scores were evaluated preoperatively, at postoperative 30 minutes, and on postoperative day 3. Secondary objectives included comparison of recovery characteristics, including eye-opening time, extubation time, Modified Aldrete Recovery Scores, and perioperative hemodynamic parameters. The study was approved by the Marmara University Faculty of Medicine Clinical Research Ethics Committee (Approval No. 09.2022.744) and written informed consent was obtained from all participants before enrollment.
Interventions
Maintenance of general anesthesia with sevoflurane inhalation. Patients were assigned to either low-flow (1 L/min) or normal-flow (3 L/min) fresh gas flow anesthesia protocols.
DRUGpropofol
Maintenance of total intravenous anesthesia using continuous propofol infusion under BIS monitoring.
DRUGRemifentanil
Continuous remifentanil infusion was administered during maintenance of anesthesia according to study protocol.
Sponsors
Gaziantep City Hospital
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Masking description
Participants were unaware of the anesthetic technique assigned to them. Postoperative cognitive assessments were performed by an outcome assessor blinded to group allocation. Anesthesia providers were aware of treatment allocation because of the nature of the interventions.
Intervention model description
Participants were randomly assigned to one of three parallel groups: low-flow sevoflurane anesthesia, normal-flow sevoflurane anesthesia, or total intravenous anesthesia (TIVA). Cognitive function was evaluated using the Mini-Mental State Examination before surgery, at postoperative 30 minutes, and on postoperative day 3.
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Age between 18 and 65 years * Body mass index (BMI) ≥30 kg/m² * ASA physical status I-III * Scheduled for elective laparoscopic abdominal surgery * Provision of written informed consent
Exclusion criteria
* History of psychiatric disease * Dementia or known cognitive impairment * Hearing or language disorders preventing MMSE assessment * Refusal to participate * Conversion from laparoscopic to open surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mini-Mental State Examination (MMSE) Score | Preoperative, postoperative 30 minutes, and postoperative day 3 | Postoperative cognitive function assessed using the Mini-Mental State Examination (MMSE). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Eye Opening Time | End of surgery | Time from discontinuation of anesthetic administration to spontaneous eye opening |
| Extubation Time | End of surgery | Time from discontinuation of anesthetic administration to tracheal extubation. |
| Modified Aldrete Recovery Score | Postoperative recovery period | Recovery status assessed using the Modified Aldrete Score. |
| heart rate | During surgery | patient's intraoperative measured heart rate |
| mean arterial pressure | during surgery | patient's intraoperative measured mean arterial pressure |
| oxygen saturation | During surgery | oxygen saturation of the patient will be recorded |
| end-tidal carbon dioxide | During surgery | end-tidal carbon dioxide of the patient will be recorded |
Countries
Turkey (Türkiye)
Contacts
PRINCIPAL_INVESTIGATORAhmet Tunca, MD
Department of Anesthesiology and Reanimation, Gaziantep City Hospital
STUDY_CHAIRSeniyye Ü Zengin, MD
Department of Anesthesiology and Reanimation, Marmara University Faculty of Medicine, Pendik Training and Research Hospital
STUDY_DIRECTORMeliha O Ergün, MD
Department of Anesthesiology and Reanimation, Marmara University Faculty of Medicine, Pendik Training and Research Hospital
Outcome results
None listed