Oxygen Reserve Index Guided FiO₂ Titration in One-Lung Ventilation

NCT07359833 | Completed FDA Device

• 1 other identifier: GaziU-AR-BA-01
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 1

Brief Summary

One-lung ventilation (OLV) is routinely used during thoracic surgery to facilitate surgical exposure but is associated with an increased risk of intraoperative hypoxemia. To prevent hypoxia, high fractions of inspired oxygen (FiO₂) are commonly administered; however, excessive oxygen delivery may lead to hyperoxia and oxidative tissue injury. The Oxygen Reserve Index (ORi) is a novel, noninvasive monitoring parameter that provides real-time information on moderate hyperoxia and may allow more precise titration of FiO₂ during anesthesia. The aim of this prospective, randomized clinical trial is to evaluate whether ORi-guided intraoperative oxygen management can reduce oxygen exposure during OLV without increasing hypoxemia and to assess its effects on oxidative stress biomarkers and postoperative outcomes. Adult patients undergoing elective thoracic surgery with OLV are randomized to receive either ORi-guided FiO₂ titration or conventional oxygen management. Oxidative stress biomarkers and postoperative pulmonary complications are compared between groups.

Conditions

One Lung Ventilation in Thoracic Surgery

Keywords

One-Lung Ventilation; oxygen reserve index; Hyperoxia; Thoracic surgery; Oxidative stress; Oxygen

Outcome Measures

Primary Outcomes (1)

• Mean intraoperative FiO₂

  The primary outcome is the mean fraction of inspired oxygen (FiO₂) administered during one-lung ventilation and throughout the entire duration of surgery, recorded continuously intraoperatively and compared between the ORi-guided and conventional oxygen management groups.

  From anesthesia induction to the extubation

Secondary Outcomes (3)

• Oxidative stress biomarkers (IL-6, SOD, MDA)

  Anesthesia induction, extubation, postoperative 12th hour, postoperative 24th hour

• Postoperative pulmonary complications

  up to 2 weeks

• Surgical site infections

  up to 2 weeks

Study Arms (2)

ORi group.

EXPERIMENTAL

In this group, intraoperative FiO₂ was titrated according to predefined Oxygen Reserve Index (ORi) thresholds during one-lung ventilation and all intraoperative period, with the aim of maintaining adequate oxygenation while avoiding unnecessary hyperoxia.

Device: Oxygen Reserve Index (ORi)-guided oxygen titration

Non-ORi group

NO INTERVENTION

In this group, intraoperative FiO₂ was adjusted based solely on pulse oximetry (SpO₂) monitoring, without the use of Oxygen Reserve Index (ORi) guidance.

Interventions

Oxygen Reserve Index (ORi)-guided oxygen titration DEVICE

FiO₂ adjusted intraoperatively according to predefined ORi thresholds during thoracic surgery and one lung ventilation period.

ORi group.

Eligibility Criteria

• Age: 18 Years - 85 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Patients age between 18-85 years Elective case Thoracic surgeries performed with one-lung ventilation using a double-lumen endotracheal tube Left ventricule ejection fraction(LVEF)\>45%

You may not qualify if:

• heart failure (LVEF) \< 45% severe valvular disease admission as an emergency case history of prior lung resection presence of peripheral arterial disease.

Sponsors & Collaborators

• Gazi University: lead

Study Sites (1)

Gazi University

Ankara, 06560, Turkey (Türkiye)

Location

Related Publications (1)

• Saracoglu A, Yamansavci Sirzai E, Yildizeli B, Yuksel M, Aykac ZZ. Oxygen reserve index guided oxygen titration in one lung ventilation with low fresh gas flow. Turk J Med Sci. 2021 Oct 21;51(5):2413-2419. doi: 10.3906/sag-2009-149.

  PMID: 34051711 RESULT

MeSH Terms

Conditions

Hyperoxia

Condition Hierarchy (Ancestors)

Signs and Symptoms, Respiratory; Signs and Symptoms; Pathological Conditions, Signs and Symptoms

Study Officials

• Buğra Aykenar

  Gazi University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Anesthesia resident

Model Details: A prospective, randomized, parallel-group clinical trial comparing ORi-guided intraoperative FiO₂ titration with conventional oxygen management in adult patients undergoing thoracic surgery with one-lung ventilation.

Study Record Dates

• First Submitted: January 17, 2026
• First Posted: January 22, 2026
• Study Start: August 5, 2022
• Primary Completion: July 15, 2023
• Study Completion: August 30, 2023
• Last Updated: January 22, 2026

Record last verified: 2022-08

Data Sharing

• IPD Sharing: Will not share

Locations

TU (1)