HyperoxiaORiNCT06566690
The Association Between Sensory Block Level, Oxygen Therapy, and ORi in Varicose Vein Patients Undergoing Spinal Anesthesia (ORi: Oxygen Reserve Index)
An observational study of Hyperoxia and Hypoxia, run by Kocaeli University at 1 site in Turkey (Türkiye).
Trial summary
The assessment of peripheral capillary oxygen saturation (SpO2) by pulse oximetry has become standard in perioperative care for the detection of hypoxaemia. The oxygen reserve index (ORI) can provide an early warning of deteriorating oxygenation long before a change in SpO2 occurs, reflect the response to oxygen… Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- What is being tested?
- Addition of ORi monitoring to SpO2 monitoring
- Type of treatment
- Medical device
- How many people
- 56 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 29 Aug 2024to 6 Mar 2026
- Phase
- Observational
- Are there results?
- None posted in the registry
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
Study population: This study aims to include ASA I-II patients aged 18-65 years scheduled for elective varicose vein surgery, with the sample size to be determined by a pilot study
Who may be able to join
- ASA I-II
Who cannot join
- Chronic Obstructive Pulmonary Disease (COPD)
- Smoking history of >30 pack-years
- Cancer patients
- Interstitial lung disease patients
- Patients with Body Mass Index (BMI) >30 kg/m²
- Patient refusal of spinal anesthesia
- Refusal to participate in the study
Trial locations and contacts
1 site in 1 country.
About this study
Official title: Association Between Sensory Block Level, Oxygen Therapy, and ORi in Varicose Vein Patients Undergoing Spinal Anesthesia: A Correlation Study
The assessment of peripheral capillary oxygen saturation (SpO2) by pulse oximetry has become standard in perioperative care for the detection of hypoxaemia. The oxygen reserve index (ORI) can provide an early warning of deteriorating oxygenation long before a change in SpO2 occurs, reflect the response to oxygen administration, facilitate oxygen titration and prevent unwanted hyperoxia. The combination of ORI with pulse oximetry can help to accurately adjust inhaled oxygen concentration and prevent hypo- and hyperoxaemia. In spinal anaesthesia, neuraxial blockade can cause paralysis of accessory respiratory muscles and theoretically lead to bronchospasm. Therefore, in this study, the investigators planned to perform oxygen saturation monitoring using two modalities. The investigators wanted to investigate the correlation between ORI, SpO2, oxygen therapy and the degree of sensory block.
Read the detailed description
The assessment of peripheral capillary oxygen saturation (SpO2) by pulse oximetry has become standard in perioperative care for the detection of hypoxaemia. The oxygen reserve index (ORI) can provide an early warning of deteriorating oxygenation long before a change in SpO2 occurs, reflect the response to oxygen administration, facilitate oxygen titration and prevent unwanted hyperoxia. The combination of ORI with pulse oximetry can help to accurately adjust inhaled oxygen concentration and prevent hypo- and hyperoxaemia. In spinal anaesthesia, neuraxial blockade can cause paralysis of accessory respiratory muscles and theoretically lead to bronchospasm. The respiratory effects of neuraxial blockade up to mid-thoracic level are minimal in patients without lung disease. While the intercostal muscles may be paralysed by thoracic block, diaphragmatic function is preserved. Therefore, in this study, the investigators planned to perform oxygen saturation monitoring using two modalities. The investigators wanted to investigate the correlation between ORI, SpO2, oxygen therapy and the degree of sensory block.
- Being tested
- Addition of ORi monitoring to SpO2 monitoring
- Keywords
- hyperoxia, hypoxia, oxygen therapy, spinal anaesthesia
- Medical subject headings
- Hyperoxia, Hypoxia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Addition of ORi monitoring to SpO2 monitoringDevice
Integration of Oxygen Reserve Index (ORi) monitoring into standard SpO2 monitoring
What is being measured
The primary outcome is the main question the study is designed to answer.
The primary outcome of this study is to assess the correlation between the need for oxygen therapy, the ascension of sensory block level, and changes in Oxygen Reserve Index (ORi).
The primary outcome measure of this study is to evaluate the potential correlation between three variables: the need for supplemental oxygen therapy, the cephalad progression of sensory block level, and fluctuations in oxygen reserve index (ORi) values.
Measured: 9 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Aug 2024
- Study start29 Aug 2024
- Primary completion10 Feb 2026
- Study completion6 Mar 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (1)Papers the sponsor has linked to this study.
- Other trials for HyperoxiaStudies 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
- Observational
- Observational model
- Case-control
- Time perspective
- Prospective
- Enrolment
- 56 participants (actual)
Sponsor and investigators
- Lead sponsor
- Kocaeli University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Volkan Alparslan, Kocaeli University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06566690
- Sponsor's protocol ID
- 2024-KAEK-02
- Acronym
- ORi
- Status last verified
- Mar 2026
- First submitted
- 20 Aug 2024
- Last updated
- 9 Mar 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Publications
Scheeren TWL, Belda FJ, Perel A. The oxygen reserve index (ORI): a new tool to monitor oxygen therapy. J Clin Monit Comput. 2018 Jun;32(3):379-389. doi: 10.1007/s10877-017-0049-4. Epub 2017 Aug 8.
PubMed 28791567
Study at a glance
From the registry record, last updated by the sponsor on 9 Mar 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Association Between Sensory Block Level, Oxygen Therapy, and ORi in Varicose Vein Patients Undergoing Spinal Anesthesia: A Correlation Study
- ClinicalTrials.gov ID
- NCT06566690
- Acronym / sponsor ID
- ORi / 2024-KAEK-02
- Keywords
- hyperoxia, hypoxia, oxygen therapy, spinal anaesthesia
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 56 participants (actual)
- Lead sponsor
- Kocaeli UniversityUniversity, hospital or other
- Study start
- 29 Aug 2024 (actual)
- Primary completion
- 10 Feb 2026 (actual)
- Study completion
- 6 Mar 2026 (actual)
- First posted
- 22 Aug 2024 (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.
The assessment of peripheral capillary oxygen saturation (SpO2) by pulse oximetry has become standard in perioperative care for the detection of hypoxaemia. The oxygen reserve index (ORI) can provide an early warning of deteriorating oxygenation long before a change in SpO2 occurs, reflect the response to oxygen administration, facilitate oxygen titration and prevent unwanted hyperoxia. The combination of ORI with pulse oximetry can help to accurately adjust inhaled oxygen concentration and prevent hypo- and hyperoxaemia. In spinal anaesthesia, neuraxial blockade can cause paralysis of accessory respiratory muscles and theoretically lead to bronchospasm. Therefore, in this study, the investigators planned to perform oxygen saturation monitoring using two modalities. The investigators wanted to investigate the correlation between ORI, SpO2, oxygen therapy and the degree of sensory block.
Detailed description
The assessment of peripheral capillary oxygen saturation (SpO2) by pulse oximetry has become standard in perioperative care for the detection of hypoxaemia. The oxygen reserve index (ORI) can provide an early warning of deteriorating oxygenation long before a change in SpO2 occurs, reflect the response to oxygen administration, facilitate oxygen titration and prevent unwanted hyperoxia. The combination of ORI with pulse oximetry can help to accurately adjust inhaled oxygen concentration and prevent hypo- and hyperoxaemia. In spinal anaesthesia, neuraxial blockade can cause paralysis of accessory respiratory muscles and theoretically lead to bronchospasm. The respiratory effects of neuraxial blockade up to mid-thoracic level are minimal in patients without lung disease. While the intercostal muscles may be paralysed by thoracic block, diaphragmatic function is preserved. Therefore, in this study, the investigators planned to perform oxygen saturation monitoring using two modalities. The investigators wanted to investigate the correlation between ORI, SpO2, oxygen therapy and the degree of sensory block.
Study design
- Observational model
- Case-control
- Time perspective
- Prospective
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
- Study population
- This study aims to include ASA I-II patients aged 18-65 years scheduled for elective varicose vein surgery, with the sample size to be determined by a pilot study
Key inclusion criteria (1 listed)
- ASA I-II
Key exclusion criteria (7 listed)
- Chronic Obstructive Pulmonary Disease (COPD)
- Smoking history of >30 pack-years
- Cancer patients
- Interstitial lung disease patients
- Patients with Body Mass Index (BMI) >30 kg/m²
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 |
|---|---|---|
| Addition of ORi monitoring to SpO2 monitoringIntegration of Oxygen Reserve Index (ORi) monitoring into standard SpO2 monitoring | Device | – |
Primary outcome
The primary outcome of this study is to assess the correlation between the need for oxygen therapy, the ascension of sensory block level, and changes in Oxygen Reserve Index (ORi).
Time frame: 9 months
The primary outcome measure of this study is to evaluate the potential correlation between three variables: the need for supplemental oxygen therapy, the cephalad progression of sensory block level, and fluctuations in oxygen reserve index (ORi) values.
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 9 Mar 2026.
- Results publication: PubMed 28791567Scheeren TWL, Belda FJ, Perel A. The oxygen reserve index (ORI): a new tool to monitor oxygen therapy. J Clin Monit Comput. 2018 Jun;32(3):379-389. doi: 10.1007/s10877-017-0049-4. Epub 2017 Aug 8.
- Related InfoLink provided by the sponsor.
- Individual participant dataSharing planned: Undecided
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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. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Hyperoxia and Hypoxia, run by Kocaeli University 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 1 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: finished, as of the sponsor's last update on 9 Mar 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?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The primary outcome of this study is to assess the correlation between the need for oxygen therapy, the ascension of sensory block level, and changes in Oxygen Reserve Index (ORi). (time frame: 9 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT06566690, which also lists 1 linked publication.
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 9 Mar 2026.