HyperoxemiaORI-BCPNCT07404267
Oxygen Reserve Index-Guided Oxygen Titration During Surgery in the Beach Chair Position
A study testing ORi-Guided FiO₂ Titration and SpO₂-Guided FiO₂ Titration in people with Hyperoxemia and Intraoperative Oxygen Therapy, run by Fatih Sultan Mehmet Training and Research Hospital at 1 site in Turkey (Türkiye).
Trial summary
This study aims to evaluate whether guidance by the Oxygen Reserve Index (ORi) improves inspiratory oxygen fraction (FiO₂) titration compared with conventional pulse oximetry (SpO₂)-guided oxygen administration in adult patients undergoing surgery in the beach chair position. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Hyperoxemia, Intraoperative Oxygen Therapy, Beach Chair Position
- What is being tested?
- ORi-Guided FiO₂ Titration and SpO₂-Guided FiO₂ Titration
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 80 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Feb 2026to 31 Jul 2026
- Phase
- Interventional
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Adult patients aged 18 to 65 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective orthopedic surgery in the beach chair position
- Body mass index (BMI) <35 kg/m²
- Ability to provide written informed consent
Who cannot join
- Age <18 or ≥65 years
- Finger deformities preventing the use of Oxygen Reserve Index (ORi) monitoring
- Severe anemia (hemoglobin <8 g/dL)
- Pregnancy
- Refusal or inability to provide informed consent
- History of stroke or significant vascular pathology
- Severe cardiac or respiratory disease
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Turkey (Türkiye)1 site
Istanbul Provincial Health Directorate Fatih Sultan Mehmet Training and Research Hospital
Istanbul, 34000
cagla sancak, MD, +90 506 438 10 02, caglasancakk@gmail.com
cansu ofluoglu, MD, +905358640564, cansuakin.iu@gmail.com
About this study
Official title: The Utility of Oxygen Reserve Index Guidance in Inspiratory Oxygen Titration for Patients Undergoing Surgery in the Beach Chair Position: A Prospective Comparative Study
This study aims to evaluate whether guidance by the Oxygen Reserve Index (ORi) improves inspiratory oxygen fraction (FiO₂) titration compared with conventional pulse oximetry (SpO₂)-guided oxygen administration in adult patients undergoing surgery in the beach chair position.
Oxygen therapy is routinely used during general anesthesia to prevent hypoxemia; however, excessive oxygen administration may result in hyperoxia, which has been associated with adverse cardiovascular and pulmonary effects. Standard pulse oximetry may not adequately detect hyperoxia when oxygen saturation values are high.
In this prospective comparative study, patients will receive oxygen titration guided either by SpO₂ alone or by combined ORi and SpO₂ monitoring. The primary outcome is the incidence of intraoperative hyperoxemia, assessed by arterial blood gas analysis. Secondary outcomes include intraoperative oxygenation parameters and hemodynamic variables.
Read the detailed description
This prospective study will be conducted in adult patients (ASA physical status I-III) undergoing elective orthopedic surgery in the beach chair position under general anesthesia. Following approval by the institutional ethics committee and acquisition of written informed consent, eligible patients will be included in the study.
Standard monitoring will include electrocardiography, noninvasive blood pressure, peripheral oxygen saturation (SpO₂), bispectral index (BIS), perfusion index (PI), pleth variability index (PVI), near-infrared spectroscopy (NIRS), and multiwavelength pulse co-oximetry for Oxygen Reserve Index (ORi) monitoring. Invasive arterial blood pressure monitoring will be established via radial arterial cannulation to allow continuous hemodynamic monitoring and arterial blood gas sampling.
General anesthesia will be induced with intravenous propofol, fentanyl, and rocuronium, followed by orotracheal intubation. Mechanical ventilation will be applied in volume-controlled mode with lung-protective settings. Anesthesia will be maintained using sevoflurane and remifentanil infusion, targeting bispectral index values between 40 and 60.
From anesthesia induction onward, inspiratory oxygen fraction (FiO₂) will be titrated either according to SpO₂ values alone or using combined ORi and SpO₂ guidance. In the ORi-guided group, FiO₂ adjustments will aim to maintain ORi values between 0.2 and 0.5, with reassessment at regular intervals. In the SpO₂-guided group, FiO₂ will be adjusted to maintain SpO₂ values at or above 98%, in accordance with routine clinical practice.
Hemodynamic parameters, oxygenation variables, ORi values, and cerebral oxygenation assessed by NIRS will be recorded at predefined time points during surgery and recovery. Arterial blood gas analysis will be performed to determine PaO₂ and arterial oxygen saturation.
Hyperoxemia will be defined as a PaO₂ value of 100 mmHg or greater and classified as mild or severe. The primary outcome of the study is the incidence of intraoperative severe hyperoxemia. Secondary outcomes include overall oxygenation profiles and intraoperative hemodynamic stability.
The results of this study are expected to provide evidence regarding the utility of ORi-guided oxygen titration in reducing unnecessary hyperoxia during surgery performed in the beach chair position.
- Being tested
- ORi-Guided FiO₂ Titration, SpO₂-Guided FiO₂ Titration
- Keywords
- Oxygen Reserve Index, ORİ, FiO2 titration, Hyperoxia, Pulse oximetry, Arterial blood gas, Near-infrared spectroscopy, General anesthesia, Beach chair position, Orthopedic surgery
- Medical subject headings
- Hyperoxia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ORi-Guided FiO₂ TitrationOther
Inspiratory oxygen fraction (FiO₂) will be adjusted throughout surgery using combined Oxygen Reserve Index (ORi) and peripheral oxygen saturation (SpO₂) monitoring. FiO₂ will be titrated to maintain ORi values between 0.2 and 0.5, with reassessment every 2-3 minutes.
SpO₂-Guided FiO₂ TitrationOther
FiO₂ will be adjusted to maintain SpO₂ at or above 98% throughout surgery.
| Study group | Role | What they receive |
|---|---|---|
| ORi-Guided FiO₂ Titration | Experimental | Inspiratory oxygen fraction (FiO₂) will be titrated using combined Oxygen Reserve Index (ORi) and peripheral oxygen saturation (SpO₂) monitoring throughout surgery. Receives: Other: ORi-Guided FiO₂ Titration |
| SpO₂-Guided Oxygen Titration | Active comparator | Inspiratory oxygen fraction (FiO₂) will be titrated based on peripheral oxygen saturation (SpO₂) values according to routine clinical practice. Receives: Other: SpO₂-Guided FiO₂ Titration |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of Intraoperative Severe Hyperoxemia
Severe hyperoxemia will be defined as an arterial partial pressure of oxygen (PaO2) ≥200 mmHg, measured by arterial blood gas analysis at predefined intraoperative time points.
Measured: Perioperative/Periprocedural
Secondary outcomes (4)
Mean Peripheral Oxygen Saturation (SpO2) During Surgery
Peripheral oxygen saturation (SpO2) measured continuously during surgery using standard pulse oximetry.
Measured: Perioperative/Periprocedural
Mean Oxygen Reserve Index (ORi) During Surgery
Oxygen Reserve Index (ORi) values recorded intraoperatively to evaluate oxygenation status.
Measured: Perioperative/Periprocedural
Mean Fraction of Inspired Oxygen (FiO₂) During Surgery
Mean fraction of inspired oxygen (FiO₂) expressed as percentage (%), averaged over the surgical period.
Measured: Perioperative/Periprocedural
Mean Cerebral Oxygen Saturation Measured by Near-Infrared Spectroscopy During Surgery
Cerebral regional oxygen saturation values measured intraoperatively using near-infrared spectroscopy.
Measured: Intraoperative period (from induction of anesthesia to end of surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted11 Feb 2026
- Study start15 Feb 2026 (estimated)
- Primary completion30 Jun 2026 (estimated)
- Study completion31 Jul 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for HyperoxemiaStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Participants will be assigned to one of two parallel groups in which inspiratory oxygen fraction (FiO₂) is titrated either using combined Oxygen Reserve Index (ORi) and SpO₂ guidance or SpO₂ guidance alone throughout surgery.
- Masking
- None (open label)
- Enrolment
- 80 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Fatih Sultan Mehmet Training and Research Hospital
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Çağla Sancak, Fatih Sultan Mehmet Training and Research Hospital
- Investigators
- cagla sancak, MD, Principal investigator, ISTANBUL PROVINCIAL HEALTH DIRECTORATE FATIH SULTAN MEHMET TRAINING AND RESEARCH HOSPITAL
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07404267
- Sponsor's protocol ID
- ORI-FIO2-BCP-2025
- Other IDs
- 2025/234
- Acronym
- ORI-BCP
- Status last verified
- Jan 2026
- First submitted
- 18 Jan 2026
- Last updated
- 11 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Study at a glance
From the registry record, last updated by the sponsor on 11 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Utility of Oxygen Reserve Index Guidance in Inspiratory Oxygen Titration for Patients Undergoing Surgery in the Beach Chair Position: A Prospective Comparative Study
- ClinicalTrials.gov ID
- NCT07404267
- Acronym / sponsor ID
- ORI-BCP / ORI-FIO2-BCP-2025
- Keywords
- Oxygen Reserve Index, ORİ, FiO2 titration, Hyperoxia, Pulse oximetry, Arterial blood gas, Near-infrared spectroscopy, General anesthesia
- Study type
- Interventional
- Recruitment status
- Not yet recruiting
- Enrolment
- 80 participants (estimated)
- Lead sponsor
- Fatih Sultan Mehmet Training and Research HospitalUniversity, hospital or other
- Study start
- 15 Feb 2026 (estimated)
- Primary completion
- 30 Jun 2026 (estimated)
- Study completion
- 31 Jul 2026 (estimated)
- First posted
- 11 Feb 2026 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to evaluate whether guidance by the Oxygen Reserve Index (ORi) improves inspiratory oxygen fraction (FiO₂) titration compared with conventional pulse oximetry (SpO₂)-guided oxygen administration in adult patients undergoing surgery in the beach chair position.
Oxygen therapy is routinely used during general anesthesia to prevent hypoxemia; however, excessive oxygen administration may result in hyperoxia, which has been associated with adverse cardiovascular and pulmonary effects. Standard pulse oximetry may not adequately detect hyperoxia when oxygen saturation values are high.
In this prospective comparative study, patients will receive oxygen titration guided either by SpO₂ alone or by combined ORi and SpO₂ monitoring. The primary outcome is the incidence of intraoperative hyperoxemia, assessed by arterial blood gas analysis. Secondary outcomes include intraoperative oxygenation parameters and hemodynamic variables.
Detailed description
This prospective study will be conducted in adult patients (ASA physical status I-III) undergoing elective orthopedic surgery in the beach chair position under general anesthesia. Following approval by the institutional ethics committee and acquisition of written informed consent, eligible patients will be included in the study.
Standard monitoring will include electrocardiography, noninvasive blood pressure, peripheral oxygen saturation (SpO₂), bispectral index (BIS), perfusion index (PI), pleth variability index (PVI), near-infrared spectroscopy (NIRS), and multiwavelength pulse co-oximetry for Oxygen Reserve Index (ORi) monitoring. Invasive arterial blood pressure monitoring will be established via radial arterial cannulation to allow continuous hemodynamic monitoring and arterial blood gas sampling.
General anesthesia will be induced with intravenous propofol, fentanyl, and rocuronium, followed by orotracheal intubation. Mechanical ventilation will be applied in volume-controlled mode with lung-protective settings. Anesthesia will be maintained using sevoflurane and remifentanil infusion, targeting bispectral index values between 40 and 60.
From anesthesia induction onward, inspiratory oxygen fraction (FiO₂) will be titrated either according to SpO₂ values alone or using combined ORi and SpO₂ guidance. In the ORi-guided group, FiO₂ adjustments will aim to maintain ORi values between 0.2 and 0.5, with reassessment at regular intervals. In the SpO₂-guided group, FiO₂ will be adjusted to maintain SpO₂ values at or above 98%, in accordance with routine clinical practice.
Hemodynamic parameters, oxygenation variables, ORi values, and cerebral oxygenation assessed by NIRS will be recorded at predefined time points during surgery and recovery. Arterial blood gas analysis will be performed to determine PaO₂ and arterial oxygen saturation.
Hyperoxemia will be defined as a PaO₂ value of 100 mmHg or greater and classified as mild or severe. The primary outcome of the study is the incidence of intraoperative severe hyperoxemia. Secondary outcomes include overall oxygenation profiles and intraoperative hemodynamic stability.
The results of this study are expected to provide evidence regarding the utility of ORi-guided oxygen titration in reducing unnecessary hyperoxia during surgery performed in the beach chair position.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Participants will be assigned to one of two parallel groups in which inspiratory oxygen fraction (FiO₂) is titrated either using combined Oxygen Reserve Index (ORi) and SpO₂ guidance or SpO₂ guidance alone throughout surgery.
| Arm | Type | Receives |
|---|---|---|
| ORi-Guided FiO₂ Titration | Experimental | Other: ORi-Guided FiO₂ TitrationInspiratory oxygen fraction (FiO₂) will be titrated using combined Oxygen Reserve Index (ORi) and peripheral oxygen saturation (SpO₂) monitoring throughout surgery. |
| SpO₂-Guided Oxygen Titration | Active comparator | Other: SpO₂-Guided FiO₂ TitrationInspiratory oxygen fraction (FiO₂) will be titrated based on peripheral oxygen saturation (SpO₂) values according to routine clinical practice. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adult patients aged 18 to 65 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective orthopedic surgery in the beach chair position
- Body mass index (BMI) <35 kg/m²
- Ability to provide written informed consent
Key exclusion criteria (7 listed)
- Age <18 or ≥65 years
- Finger deformities preventing the use of Oxygen Reserve Index (ORi) monitoring
- Severe anemia (hemoglobin <8 g/dL)
- Pregnancy
- Refusal or inability to provide informed consent
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| ORi-Guided FiO₂ TitrationInspiratory oxygen fraction (FiO₂) will be adjusted throughout surgery using combined Oxygen Reserve Index (ORi) and peripheral oxygen saturation (SpO₂) monitoring. FiO₂ will be titrated to maintain ORi values between 0.2 and 0.5, with reassessment every 2-3 minutes. | Other | ORi-Guided FiO₂ Titration |
| SpO₂-Guided FiO₂ TitrationFiO₂ will be adjusted to maintain SpO₂ at or above 98% throughout surgery. | Other | SpO₂-Guided Oxygen Titration |
Primary outcome
Incidence of Intraoperative Severe Hyperoxemia
Time frame: Perioperative/Periprocedural
Severe hyperoxemia will be defined as an arterial partial pressure of oxygen (PaO2) ≥200 mmHg, measured by arterial blood gas analysis at predefined intraoperative time points.
4 secondary outcomes
Mean Peripheral Oxygen Saturation (SpO2) During Surgery
Time frame: Perioperative/Periprocedural
Mean Oxygen Reserve Index (ORi) During Surgery
Time frame: Perioperative/Periprocedural
Mean Fraction of Inspired Oxygen (FiO₂) During Surgery
Time frame: Perioperative/Periprocedural
Mean Cerebral Oxygen Saturation Measured by Near-Infrared Spectroscopy During Surgery
Time frame: Intraoperative period (from induction of anesthesia to end of surgery)
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Feb 2026.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
cagla sancak, MD principal investigator
ISTANBUL PROVINCIAL HEALTH DIRECTORATE FATIH SULTAN MEHMET TRAINING AND RESEARCH HOSPITAL
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing ORi-Guided FiO₂ Titration and SpO₂-Guided FiO₂ Titration in people with Hyperoxemia and Intraoperative Oxygen Therapy, run by Fatih Sultan Mehmet Training and Research Hospital at 1 site in Turkey (Türkiye).
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: opening soon, as of the sponsor's last update on 11 Feb 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Turkey (Türkiye). Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact cagla sancak, md (+905064381002 ext. +90216 578 30, caglasancakk@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Incidence of Intraoperative Severe Hyperoxemia (time frame: Perioperative/Periprocedural). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Feb 2026.