Effects of Trendelenburg Position and Pneumoperitoneum on Mechanical Power and Respiratory Mechanics During V-NOTES Surgery

NCT07885111 | Not Yet Recruiting

• 1 other identifier: Bayvazoglu
• Study Type: observational
• Target: 14
• Locations: 0 countries
• Sites: N/A

Brief Summary

The purpose of this observational study is to evaluate the effects of Trendelenburg positioning and pneumoperitoneum on mechanical power and respiratory mechanics in adult women undergoing vaginal natural orifice transluminal endoscopic surgery (vNOTES) for bilateral tubal ligation. The main questions this study aims to answer are:

• Does Trendelenburg positioning and pneumoperitoneum increase mechanical power during vNOTES surgery?
• How do Trendelenburg positioning and pneumoperitoneum affect respiratory mechanics, including driving pressure, lung compliance, and airway pressures? Participants who are already scheduled to undergo vNOTES bilateral tubal ligation as part of their routine medical care will receive standard general anesthesia and mechanical ventilation. Researchers will record mechanical power and respiratory parameters at six predefined time points during surgery, before and after the application of pneumoperitoneum and Trendelenburg positioning. A total of 14 adult women will be included. No additional experimental treatment or intervention will be performed as part of the study.

Conditions

Respiratory Mechanics During vNOTES Surgery

Outcome Measures

Primary Outcomes (1)

• Changes in Intraoperative Mechanical Power During vNOTES Surgery

  Mechanical power (J/min) will be calculated using recorded mechanical ventilation parameters. Changes in mechanical power associated with pneumoperitoneum and Trendelenburg positioning will be evaluated at six predefined intraoperative time points (T0-T5). Kopyala

  Intraoperatively, from immediately after endotracheal intubation to the end of surgery, at six predefined time points (T0-T5).

Secondary Outcomes (3)

• Changes in Intraoperative Driving Pressure

  Intraoperatively, from immediately after endotracheal intubation to the end of surgery, at six predefined time points (T0-T5).

• Changes in Static Respiratory System Compliance

  Intraoperatively, from immediately after endotracheal intubation to the end of surgery, at six predefined time points (T0-T5).

• Changes in Dynamic Respiratory System Compliance

  Intraoperatively, from immediately after endotracheal intubation to the end of surgery, at six predefined time points (T0-T5).

Study Arms (1)

Patients Undergoing vNOTES Surgery

This cohort will include 14 adult female patients undergoing elective bilateral tubal ligation using the vaginal natural orifice transluminal endoscopic surgery (vNOTES) technique under general anesthesia with controlled mechanical ventilation. All participants will receive standard surgical and anesthetic care. Trendelenburg positioning and pneumoperitoneum will be performed as part of the routine surgical procedure. Mechanical power and respiratory mechanics parameters will be recorded at six predefined intraoperative time points to evaluate changes associated with Trendelenburg positioning and pneumoperitoneum. No additional experimental intervention or modification of routine clinical care will be performed.

Eligibility Criteria

• Age: 18 Years+
• Gender Eligibility Details: Only female patients undergoing elective bilateral tubal ligation using the vNOTES technique are eligible for this study.
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The study population will consist of 14 adult female patients aged 18 years or older who are scheduled to undergo elective bilateral tubal ligation using the vaginal natural orifice transluminal endoscopic surgery (vNOTES) technique at Yahyali State Hospital, Kayseri, Türkiye. Eligible participants will have an American Society of Anesthesiologists (ASA) physical status of I-III and will undergo general anesthesia with endotracheal intubation and controlled mechanical ventilation. Participants will be recruited prospectively from patients scheduled for elective vNOTES surgery. All patients will receive standard surgical and anesthetic care without any study-specific intervention.

You may qualify if:

• Female patients aged 18 years or older.
• Scheduled for elective bilateral tubal ligation using the vaginal natural orifice transluminal endoscopic surgery (vNOTES) technique at Yahyali State Hospital.
• Requesting permanent contraception and considered surgically eligible for bilateral tubal ligation.
• American Society of Anesthesiologists (ASA) physical status I, II, or III.
• Scheduled to undergo general anesthesia with endotracheal intubation and controlled mechanical ventilation.
• Eligible for the standardized anesthesia and mechanical ventilation protocol.
• No clinical condition preventing reliable intraoperative recording of ventilation parameters and respiratory mechanics.
• Willing to participate in the study and undergo the planned intraoperative measurements.
• Able to provide written informed consent.

You may not qualify if:

• Age younger than 18 years.
• Emergency surgery.
• Surgery performed using a technique other than vNOTES or conversion to conventional laparoscopy or open surgery.
• ASA physical status IV or higher.
• Severe chronic pulmonary disease, including severe chronic obstructive pulmonary disease, severe asthma, or interstitial lung disease.
• Uncontrolled cardiovascular disease or advanced heart failure.
• Body mass index (BMI) ≥35 kg/m².
• Pregnancy or suspected pregnancy.
• Chest wall deformity or neuromuscular disease that may affect mechanical ventilation parameters.
• Missing or unreliable intraoperative measurements.
• Refusal to participate or failure to provide written informed consent.

Sponsors & Collaborators

• Burcu Ayvazoğlu: lead

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Anesthesiology and Reanimation Specialist

Study Record Dates

• First Submitted: October 13, 2026
• First Posted: October 21, 2026
• Study Start: October 15, 2026
• Primary Completion (Estimated): December 15, 2026
• Study Completion (Estimated): December 30, 2026
• Last Updated: October 21, 2026

Record last verified: 2026-10

Data Sharing

• IPD Sharing: Will not share