The Effect of Positive End-Expiratory Pressure Levels on Perfusion Index and Neurocognitive Functions in Geriatric Patients

NCT07505550 | Completed

• 1 other identifier: Geriatric and PEEP
• Study Type: interventional
• Target: 78
• Locations: 1 country
• Sites: 1

Brief Summary

With the increasing geriatric population, age-related physiological changes and common comorbidities increase the risk of surgical and anesthesia-related complications in this patient group. Therefore, careful planning of anesthesia management and ventilation strategies is crucial to achieve safe and successful clinical outcomes. Positive end-expiratory pressure (PEEP), one of these strategies, should be applied with careful consideration of the balance between ensuring oxygenation and maintaining cardiovascular stability in geriatric patients. Early detection of hypoperfusion during the intraoperative period is also an important part of perioperative management. To this end, near-infrared spectroscopy (NIRS) is used as a noninvasive monitoring method to assess cerebral oxygenation, while the perfusion index (PI) is used to evaluate peripheral circulation, providing clinicians with valuable information for predicting potential complications. However, one of the most important neurological complications that can occur after surgery in geriatric patients is postoperative cognitive dysfunction (POCD). The Mini-Mental State Examination (MMSE) is widely preferred for assessing cognitive function during the perioperative period due to its ease of application and reliability. The primary objective of this study is to investigate the effects of different PEEP levels on PI in geriatric patients undergoing laparoscopic cholecystectomy and to reveal changes in neurocognitive function by comparing preoperative and postoperative MMSE scores. Our secondary objectives are to evaluate the effects of PEEP on NIRS values and to analyze the possible relationships between NIRS, PI, hemodynamic parameters, and MMSE scores.

Conditions

General Anesthesia; Elective Laparoscopic Cholecystectomy

Keywords

Geriatric Patient; Laparoscopic Cholecystectomy; Near Infrared Spectroscopy; Perfusion Index; Positive End-Expiratory Pressure; Post-Operative Cognitive Dysfunction

Outcome Measures

Primary Outcomes (2)

• Neurocognitive functions

  The diagnosis of postoperative cognitive dysfunction is based on the evaluation of differences in preoperative and postoperative cognitive performance. One of the most commonly used methods for assessing cognitive functions is the Mini-Mental State Examination (MMSE). The MMSE covers subheadings such as orientation, memory, language, attention, calculation, and recall, and is scored out of 30 points. Results are interpreted as follows: 24-30 points indicate normal cognitive function, 18-23 points indicate mild cognitive impairment, and 0-17 points indicate moderate to severe cognitive impairment.

  2 hours before the operation and on the first postoperative day, The MMSE test was administered again to patients and the results were recorded.

• Evaluate changes in perfusion index (PI)

  Perfusion index (PI) is defined as the ratio of the pulsatile signal obtained by photoplethysmography to the nonpulsatile signal. Photoplethysmography is a noninvasive, rapidly applicable method widely used in intraoperative patient monitoring. PI is an indirect indicator of central and peripheral perfusion and is primarily determined by the sympathetic-parasympathetic balance that regulates cardiac output and vascular tone. Changes in PI were evaluated at different applied PEEP levels.

  Baseline, 1 minute after anesthesia induction; 1 minute after intubation; 1 minute before pneumoperitoneum;at 1, 5, 10, 15, 30, 45, 60, 90, 120 and 150 minutes after pneumoperitoneum;1 minutes after at the end of pneumoperitoneum, surgery and extubation.

Secondary Outcomes (4)

• Evaluate changes in near infrared spectroscopy (NIRS)

  Baseline, 1 minute after anesthesia induction; 1 minute after intubation; 1 minute before pneumoperitoneum;at 1, 5, 10, 15, 30, 45, 60, 90, 120 and 150 minutes after pneumoperitoneum;1 minutes after at the end of pneumoperitoneum, surgery and extubation.

• To determine the possible correlations between NIRS and hemodynamic data

  Baseline, 1 minute after anesthesia induction; 1 minute after intubation; 1 minute before pneumoperitoneum;at 1, 5, 10, 15, 30, 45, 60, 90, 120 and 150 minutes after pneumoperitoneum;1 minutes after at the end of pneumoperitoneum, surgery and extubation.

• To determine the possible correlations between PI and hemodynamic data

  Baseline, 1 minute after anesthesia induction; 1 minute after intubation; 1 minute before pneumoperitoneum;at 1, 5, 10, 15, 30, 45, 60, 90, 120 and 150 minutes after pneumoperitoneum;1 minutes after at the end of pneumoperitoneum, surgery and extubation.

• To determine the possible correlations between PI and MMSE scores

  2 hours before surgery through postoperative day 1

Study Arms (3)

5 cmH₂O PEEP Ventilation

ACTIVE COMPARATOR

Group 5 was ventilated with 5 cmH₂O PEEP.

Other: PEEP levels

7 cmH₂O PEEP Ventilation

ACTIVE COMPARATOR

Group 7 was ventilated with 7 cmH₂O PEEP.

Other: PEEP levels

9 cmH₂O PEEP Ventilation

ACTIVE COMPARATOR

Group 9 was ventilated with 9 cmH₂O PEEP.

Other: PEEP levels

Interventions

PEEP levels OTHER

78 patients undergoing elective surgery in the General Surgery Operating Room were divided into three groups using a computer-assisted randomization method. Group 5 was ventilated with 5 cmH₂O PEEP, Group 7 with 7 cmH₂O PEEP, and Group 9 with 9 cmH₂O PEEP.

5 cmH₂O PEEP Ventilation; 7 cmH₂O PEEP Ventilation; 9 cmH₂O PEEP Ventilation

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Older Adult (65+)

You may qualify if:

• Patients who are 65 years and older
• Patients in the ASA I-III risk group
• Under elective conditions, patients those undergo elective laparoscopic cholecystectomy
• Voluntary patients

You may not qualify if:

• Patients under age 65
• Emergency surgical procedures
• Patients with neurological or psychiatric disorders
• Patients with severe restrictive or obstructive lung disease
• Patients with serious cardiac pathology (EF\<40 or presence of arrhythmia)
• Patients with peripheral artery disease
• Patients with increased intracranial pressure
• Morbidly obese patients
• Patients do not want to participate in the study

Sponsors & Collaborators

• Ankara City Hospital Bilkent: lead

Study Sites (1)

Ankara Bilkent City Hospital

Ankara, Çankaya, 06800, Turkey (Türkiye)

Location

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: SCREENING
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Prof. MD

Study Record Dates

• First Submitted: February 18, 2026
• First Posted: April 1, 2026
• Study Start: April 2, 2025
• Primary Completion: August 15, 2025
• Study Completion: August 29, 2025
• Last Updated: April 1, 2026

Record last verified: 2026-03

Locations

TU (1)