Cerebral Hemodynamic Effects of Individualized PEEP During Robotic Prostatectomy

NCT07784010 | Not Yet Recruiting

• 1 other identifier: E-24687260-604.01-1662792
• Study Type: interventional
• Target: 45
• Locations: 1 country
• Sites: 1

Brief Summary

This randomized clinical trial will compare two approaches to setting positive end-expiratory pressure (PEEP) during robot-assisted radical prostatectomy performed in the Trendelenburg position. The study aims to determine whether individualized PEEP, selected according to the lowest driving pressure, affects cerebral blood flow and brain oxygenation differently from standard PEEP. Approximately 45 adult patients undergoing robot-assisted radical prostatectomy will be randomly assigned to receive either individualized PEEP or standard PEEP during general anesthesia. Cerebral blood flow will be assessed noninvasively using transcranial Doppler ultrasound, and brain oxygenation will be monitored using near-infrared spectroscopy. Participants will also undergo brief assessments of attention, cognitive function, delirium, and sedation before and after surgery, with follow-up continuing for up to 48 hours after the operation. Both ventilation approaches are routinely used in clinical practice, and no experimental drug, device, or additional invasive procedure will be used as part of the study.

Conditions

Cerebral Hemodynamics; Mechanical Ventilation Strategies; Robotic Prostatectomy

Keywords

Positive End-Expiratory Pressure (PEEP); Driving Pressure; Transcranial Doppler Ultrasonography; Cerebral Hemodynamics; Robot-Assisted Radical Prostatectomy; Individualized PEEP; Near-Infrared Spectroscopy; Postoperative Cognitive Function

Outcome Measures

Primary Outcomes (1)

• Change in Noninvasive Estimated Intracranial Pressure

  Noninvasive estimated intracranial pressure (nICPPI), expressed in mmHg, will be calculated from the middle cerebral artery pulsatility index (PI) measured by transcranial Doppler ultrasonography using the formula nICPPI = 10.93 × PI - 1.28. The outcome is the change in nICPPI from after anesthesia induction to 60 minutes after initiation of steep Trendelenburg position and pneumoperitoneum, calculated as the later value minus the post-induction value.

  After anesthesia induction and 60 minutes after initiation of steep Trendelenburg position and pneumoperitoneum

Secondary Outcomes (6)

• Middle Cerebral Artery Pulsatility Index

  After anesthesia induction; 60 minutes after initiation of steep Trendelenburg position and pneumoperitoneum; and 10 minutes after termination of Trendelenburg position and pneumoperitoneum, before emergence from anesthesia

• Middle Cerebral Artery Resistance Index

  After anesthesia induction; 60 minutes after initiation of steep Trendelenburg position and pneumoperitoneum; and 10 minutes after termination of Trendelenburg position and pneumoperitoneum, before emergence from anesthesia

• Regional Cerebral Oxygen Saturation Measured by Near-Infrared Spectroscopy

  Before anesthesia induction; after anesthesia induction; 30 and 60 minutes after initiation of steep Trendelenburg position and pneumoperitoneum; immediately before termination of Trendelenburg position; and 10 minutes after termination, before emergence

• Months Backward Test Performance Score

  Preoperatively and at 12, 24, 36, and 48 hours after surgery

• Nursing Delirium Screening Scale Total Score

  In the post-anesthesia care unit or intensive care unit, and at 12, 24, 36, and 48 hours after surgery

Study Arms (2)

Individualized PEEP Group

EXPERIMENTAL

Patients assigned to this group will undergo a recruitment maneuver followed by decremental PEEP titration from 15 to 5 cmH2O in 1-cmH2O steps. After 12 respiratory cycles at each PEEP level, the PEEP associated with the lowest driving pressure will be selected and maintained.

Other: Individualized PEEP Titration

Standard PEEP Group

ACTIVE COMPARATOR

Patients assigned to this group will undergo a recruitment maneuver followed by standard fixed PEEP of 6 cmH2O during mechanical ventilation.

Other: Standard PEEP Group

Interventions

Individualized PEEP Titration OTHER

Following a recruitment maneuver, PEEP will be decreased from 15 to 5 cmH2O in 1-cmH2O steps. Respiratory mechanics will be assessed after 12 respiratory cycles at each step, and the PEEP level producing the lowest driving pressure will be selected as the individualized PEEP and maintained.

Also known as: Driving Pressure-Guided PEEP

Individualized PEEP Group

Standard PEEP Group OTHER

Following a recruitment maneuver, PEEP will be maintained at a fixed level of 6 cmH2O during mechanical ventilation.

Standard PEEP Group

Eligibility Criteria

• Age: 18 Years - 80 Years
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Age 18 to 80 years American Society of Anesthesiologists (ASA) physical status I-III Scheduled for robot-assisted laparoscopic radical prostatectomy Provision of written informed consent

You may not qualify if:

• Body mass index (BMI) \>35 kg/m² History of surgery requiring at least 1 hour of mechanical ventilation within the previous 2 weeks Severe pulmonary disease New York Heart Association (NYHA) class III-IV heart failure Progressive neuromuscular disease Known cerebrovascular malformation Head or neck anatomical conditions preventing adequate transcranial Doppler ultrasonography Refusal to participate in the study Intraoperative conversion to open surgery

Sponsors & Collaborators

• Istanbul University: lead

Study Sites (1)

Istanbul University-Cerrahpasa, Cerrahpasa Faculty of Medicine

Istanbul, 34077, Turkey (Türkiye)

Location

Central Study Contacts

Ezgi Budak Özyalçın

CONTACT

+905056043177; budakezgi@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: TRIPLE
• Who Masked: PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: Participants, investigators not involved in administration of the assigned ventilation strategy, the transcranial Doppler operator, postoperative outcome assessors, and the statistician will be blinded to group allocation. The anesthesiologist responsible for implementing the assigned PEEP strategy will not be blinded because knowledge of group allocation is required to perform the intervention.
• Purpose: BASIC SCIENCE
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Specialist Doctor

Study Record Dates

• First Submitted: August 18, 2026
• First Posted: August 25, 2026
• Study Start: August 19, 2026
• Primary Completion (Estimated): November 19, 2026
• Study Completion (Estimated): November 30, 2026
• Last Updated: August 25, 2026

Record last verified: 2026-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)