Laparoscopic Gynecological Surgery
Conditions
Keywords
Trendelenburg position, Optic Nerve Sheath Diameter, Near-Infrared Spectroscopy, Cerebral Oxygenation, Intracranial Pressure, Modified Z-Trendelenburg, Pneumoperitoneum, Laparoscopic surgery
Brief summary
The purpose of this study is to compare the effects of the standard Trendelenburg position and the modified Z-Trendelenburg position on cerebral oxygenation and optic nerve sheath diameter (ONSD) in patients undergoing laparoscopic surgery. The prolonged use of the standard Trendelenburg position combined with pneumoperitoneum can increase intracranial pressure and affect cerebral blood flow. In this study, researchers will use non-invasive methods, including Near-Infrared Spectroscopy (NIRS) to monitor regional cerebral oxygenation, and ocular ultrasonography to measure ONSD as an indicator of intracranial pressure changes. The main goal is to determine whether the modified Z-Trendelenburg position serves as a safer physiological alternative by reducing these potential adverse effects compared to the standard position.
Detailed description
Laparoscopic surgeries frequently require patients to be placed in a steep Trendelenburg position with pneumoperitoneum to provide optimal surgical exposure. However, this combination induces significant physiological alterations, most notably an increase in intracranial pressure (ICP) and a potential compromise in cerebral venous drainage and regional cerebral oxygen saturation (rSO2). Non-invasive monitoring techniques, such as measuring the optic nerve sheath diameter (ONSD) via ultrasonography, provide reliable, real-time estimates of ICP changes. Additionally, Near-Infrared Spectroscopy (NIRS) allows for the continuous monitoring of cerebral oxygenation. This prospective clinical study is designed to evaluate and compare the cerebral and hemodynamic impacts of the standard straight Trendelenburg position versus a modified Z-Trendelenburg position. Participants scheduled for elective laparoscopic procedures will be divided into specific positioning groups. Hemodynamic parameters, NIRS values, and ONSD measurements will be recorded at predefined time points throughout the surgery: at baseline, post-induction, after the establishment of pneumoperitoneum and positioning, at specific intervals during the surgery, and post-operatively in the recovery room. The primary hypothesis is that the modified Z-Trendelenburg position will attenuate the rise in ICP (reflected by a smaller increase in ONSD) and provide better cerebral oxygenation stability compared to the traditional standard position.
Interventions
PROCEDUREStandard Trendelenburg Position
Placement of the patient in the traditional straight head-down tilt position required for laparoscopic surgical access and pneumoperitoneum
PROCEDUREModified Z-Trendelenburg Position
Placement of the patient in a modified head-down tilt position combined with leg flexion
Sponsors
Ankara Etlik City Hospital
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
FEMALE
Age
18 Years to 80 Years
Healthy volunteers
Yes
Inclusion criteria
Patients aged between 18 and 70 years American Society of Anesthesiologists (ASA) physical status I or II Scheduled for elective laparoscopic surgery requiring Trendelenburg position Provided written informed consent
Exclusion criteria
Patient refusal to participate History of severe cerebrovascular disease Known increased intracranial pressure Pre-existing ocular pathology that could affect optic nerve sheath diameter (ONSD) measurements (e.g., glaucoma, optic neuritis, ocular trauma) Severe cardiovascular or pulmonary disease Body Mass Index (BMI) greater than 35 kg/m\^2 Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Regional Cerebral Oxygen Saturation (rSO2) | Baseline (before anesthesia induction), at 10, 45, 60, and 90 minutes after establishing pneumoperitoneum and surgical positioning, and 10 minutes after returning to the supine position. | Regional cerebral oxygen saturation (rSO2) will be measured bilaterally using Near-Infrared Spectroscopy (NIRS) sensors placed on the patient's forehead. This non-invasive monitoring will be used to evaluate cerebral oxygenation changes during different surgical positions and pneumoperitoneum. Values will be recorded as percentages (%). |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Mean Arterial Pressure (MAP) | Baseline ( 10 minutes after anesthesia induction), at 10,45, 60, and 90 minutes after establishing pneumoperitoneum and surgical positioning, and 10 minutes after returning to the supine position. | Mean Arterial Pressure (MAP) will be continuously monitored and recorded to evaluate the cardiovascular effects of the pneumoperitoneum and modified positioning. Values will be reported in mmHg. |
| Change in Optic Nerve Sheath Diameter (ONSD) | Baseline ( 10 minutes after anesthesia induction), at 10, 45, 60, and 90 minutes after establishing pneumoperitoneum and surgical positioning, and 10 minutes after returning to the supine position. | Intracranial pressure changes will be evaluated indirectly by measuring the optic nerve sheath diameter (ONSD) using ocular ultrasonography. Measurements will be taken bilaterally and recorded in millimeters (mm). |
| Change in Peak Airway Pressure (Ppeak) | Baseline (10 minutes after anesthesia induction), at 10,45, 60, and 90 minutes after establishing pneumoperitoneum and surgical positioning, and 10 minutes after returning to the supine posi | Peak airway pressure will be monitored continuously and recorded to evaluate the effects of pneumoperitoneum and different surgical positions on respiratory mechanics. Values will be reported in centimeters of water (cmH2O). |
| Change in End-tidal Carbon Dioxide (EtCO2) | Baseline (10 minutes after anesthesia induction), at 10, 45, 60, and 90 minutes after establishing pneumoperitoneum and surgical positioning, and 10 minutes after returning to the supine positi | End-tidal carbon dioxide levels will be monitored continuously via capnography to evaluate ventilation status during pneumoperitoneum and different positioning. Values will be reported in millimeters of mercury (mmHg). |
Countries
Turkey (Türkiye)
Outcome results
None listed