Effect of ORI-guided Oxygen Titration on Oxidative Stress in Rhinoplasty Surgery

NCT ID: NCT07158073

Last Updated: 2025-09-08

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 60 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2021-03-01
• Study Completion Date: 2021-08-30

Brief Summary

The aim of this study is to evaluate whether the use of Oxygen Reserve Index (ORİ) can prevent hyperoxia in patients undergoing rhinoplasty surgery and whether it can reduce oxidative stress caused by hyperoxia.

Detailed Description

ORI is a continuous, non-invasive parameter provided by new-generation pulse oximeters utilizing multi-wavelength pulse oximetry technology. ORI serves as an important monitoring tool for detecting both hyperoxemia and desaturation in patients with decreased PaO₂ levels. Studies have demonstrated that ORI provides values within a range of 0 to 1, and an ORI value of 0 corresponds to a PaO₂ level between 80 and 125 mmHg.

Oxygen is commonly used in clinical practice to prevent or treat hypoxia; however, excessive use may lead to oxidative stress. Oxidative stress is defined as a disruption of the oxidative balance resulting from an increased generation of reactive oxygen species (ROS) during cellular metabolism and an insufficient level of antioxidants to detoxify them. ROS are formed by the reaction of molecular oxygen with H₂O, the most stable form of oxygen. In this reaction, the stepwise addition of electrons to molecular oxygen (O₂) leads to the formation of superoxide anion (O₂ˉ), hydrogen peroxide (H₂O₂), and hydroxyl radical (-OH). Among these, the hydroxyl radical is the most reactive form of oxygen radicals.

Although ROS are essential for normal cellular functions such as intracellular signaling and defense against external threats, their excessive production can lead to molecular and cellular dysfunction. Excessive ROS attack nucleotide bases in nucleic acids, amino acid side chains in proteins, and double bonds in unsaturated fatty acids, resulting in oxidative stress that damages DNA, RNA, proteins, and lipids, leading to structural and metabolic changes in cells.

The primary aim of the investigators in this study is to determine whether ORI-guided oxygen titration during rhinoplasty surgery can help prevent hyperoxia and reduce oxidative stress compared with conventional oxygen therapy. To evaluate oxidative stress, thiol-disulfide balance and ischemia-modified albumin (IMA) levels will be assessed in the participants.

Conditions

Rhinoplasty; Oxidative Stress; Hyperoxia; Oxygen Reserve Index

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: PREVENTION
• Blinding Strategy: QUADRUPLE

Study Groups

ORI group (Group R)

Patients in Group R received ORI monitoring in addition to intraoperative standart monitoring (ECG, pulse oximetry, non-invasive arterial blood pressure). For this purpose, an ORI sensor (RD Rainbow SET sensor, Masimo Corp., Irvine, CA, USA) was placed on the fourth finger of the upper extremity where there was no blood pressure cuff. The sensor was wrapped to prevent exposure to light and connected to an oximeter device (Raical-7® Pulse CO-Oximater®, Masimo Corp., Irvine, CA, USA).In Group R, mask ventilation was administered with 50% oxygen. FiO₂ was titrated between 30% and 50% under the guidance of ORI and SpO₂ values. Accordingly, if SpO₂ was ≥ 98%, FiO₂ was reduced in 5% increments to a minimum of 30%, aiming to achieve an ORI value of 0 or as close to 0 as possible.

Group Type: ACTIVE_COMPARATOR

FiO₂ titration, under the guidance of ORI

Intervention Type: DEVICE

In Group R, FiO₂ was titrated between 30% and 50% under the guidance of ORI and SpO₂ values. Accordingly, if SpO₂ was ≥ 98%, FiO₂ was reduced in 5% increments to a minimum of 30%, aiming to achieve an ORI value of 0 or as close to 0 as possible.

Control group (Group C)

Patients in Group C received only standard monitoring. Mask ventilation was administered with 100% oxygen. FiO₂ was maintained at 50% throughout the surgery, provided that SpO₂ remained ≥ 98%.

Group Type: ACTIVE_COMPARATOR

Conventional oxygen administration

Intervention Type: DEVICE

In Group C, FiO₂ was maintained at 50% throughout the surgery, provided that SpO₂ remained ≥ 98%.

Interventions

FiO₂ titration, under the guidance of ORI

In Group R, FiO₂ was titrated between 30% and 50% under the guidance of ORI and SpO₂ values. Accordingly, if SpO₂ was ≥ 98%, FiO₂ was reduced in 5% increments to a minimum of 30%, aiming to achieve an ORI value of 0 or as close to 0 as possible.

Intervention Type: DEVICE

Conventional oxygen administration

In Group C, FiO₂ was maintained at 50% throughout the surgery, provided that SpO₂ remained ≥ 98%.

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• classified as ASA physical status I or II

Exclusion Criteria

• under 18 years of age
• ASA classification greater than II
• Mallampati score of 3 or 4
• findings suggestive of difficult intubation during physical examination
• any pathological findings on chest X-ray evaluation (e.g., pleural effusion, nodular density increase, emphysema, atelectasis, calcification, mediastinal widening, or infiltration)
• a history of circulatory disorders
• hematocrit or hemoglobin values outside the normal range (Hemoglobin: 12-16 g/dL for males, 11-14 g/dL for females; Hematocrit: 36-48% for males, 33-42% for females)
• a known hypersensitivity to any anesthetic agent to be used in the study.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: No

Sponsors

Dr. Lutfi Kirdar Kartal Training and Research Hospital

OTHER_GOV

Sponsor Role: lead

Responsible Party

Recep Karakaşoğlu

MD

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Banu E Çevik, MD

Role: STUDY_DIRECTOR

University of Health Sciences, Kartal Dr. Lütfi Kırdar City Hospital

Fatih D Geyik, MD

Role: PRINCIPAL_INVESTIGATOR

University of Health Sciences, Kartal Dr. Lütfi Kırdar City Hospital

Kemal T Saraçoğlu, MD

Role: PRINCIPAL_INVESTIGATOR

University of Health Sciences, Kartal Dr. Lütfi Kırdar City Hospital

Recep karakaşoğlu, MD

Role: PRINCIPAL_INVESTIGATOR

University of Health Sciences, Kartal Dr. Lütfi Kırdar City Hospital

Locations

Kartal Dr. Lütfi Kırdar City Hospital

Istanbul, kartal, Turkey (Türkiye)

Countries

Turkey (Türkiye)

Other Identifiers

DLKCH-AR-RK-01

Identifier Type: -

Identifier Source: org_study_id