Laparoscopic Colorectal SurgeryNCT07445698
Oxygen Reserve Index in Laparoscopic Colorectal Surgery
An observational study of Laparoscopic Colorectal Surgery, run by Dr. Lutfi Kirdar Kartal Training and Research Hospital at 1 site in Turkey (Türkiye).
Trial summary
During laparoscopic procedures, certain physiological changes occur due to the creation of pneumoperitoneum. One such change is the reduction in portal venous blood flow, which can lead to decreased liver perfusion and acute liver cell injury. Read more about this study
- Who is it for?
- Ages 18 to 75 years
- Conditions the study is for
- Laparoscopic Colorectal Surgery
- What is being tested?
- Oxygen Administration During Extubation
- Type of treatment
- Lifestyle or therapy programme
- How many people
- 60 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 7 Jan 2025to 10 Feb 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 75 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Sixty volunteer patients, aged between 18 and 75, with a Body Mass Index (BMI) below 35 and ASA class I-III, who are scheduled to undergo elective laparoscopic colorectal surgery , will be included.
Who may be able to join
- Age: 18-75
- ASA: I-III
- Scheduled for elective laparoscopic surgery
- BMI <35
Who cannot join
- Patients undergoing emergency surgery due to trauma
- Patients with ASA physical status classification IV or higher
- Patients requiring intensive care unit admission
- Patients with active, clinically symptomatic anemia
- Patients with heart failure
- Patients with known allergy to the sensor material to be used
Show all 13Show fewer
- Patients with difficult mask ventilation or difficult intubation
- Patients with a platelet count below 30,000/mm³
- Patients with a history of gastrointestinal bleeding within the past 6 months
- Patients with a history of bleeding diathesis or increased risk of intracerebral hemorrhage
- Patients with oliguria and/or those who required dialysis or underwent dialysis within one month prior to surgery
- Patients with a known hypersensitivity reaction to any anesthetic or analgesic drug used in the study
- Patients who do not wish to participate in the study
Trial locations and contacts
1 site in 1 country.
Turkey (Türkiye)1 site
Kartal Dr. Lütfi Kırdar Eğitim ve Araştırma hastanesi
Istanbul, Kartal, 34865
About this study
Official title: Comparison of the Effects of 100% and 80% Oxygen Use During Extubation on Oxygen Reserve Index in Laparoscopic Colorectal Surgery
During laparoscopic procedures, certain physiological changes occur due to the creation of pneumoperitoneum. One such change is the reduction in portal venous blood flow, which can lead to decreased liver perfusion and acute liver cell injury. Additionally, due to an increased alveolar-arterial oxygen pressure gradient, postoperative atelectasis may occur, leading to hypoxia.
In other words, the increased intra-abdominal pressure during laparoscopic surgery-along with the effects of patient positioning and mechanical ventilation used during anesthesia-can worsen low blood oxygen levels, especially in patients with already reduced lung compliance and higher metabolic demands. This makes close monitoring of oxygenation crucial.
Read more
The Oxygen Reserve Index (ORI) is a relatively new tool that can help monitor both high oxygen levels (hyperoxemia) and drops in oxygen (desaturation) before they become clinically apparent. Studies have shown that ORI values range from 0 to 1, with an ORI of 0 typically corresponding to a PaO₂ level between 80-125 mmHg. A downward trend in ORI can act as an early warning sign of hypoxemia, giving clinicians a chance to act before it's too late.
Many studies have highlighted the potential harms of using high oxygen concentrations during surgery. For example, while most hospitals still give patients 100% oxygen before anesthesia (a process called preoxygenation), recent evidence suggests this might increase the risk of atelectasis. Therefore, using 80% or less oxygen is now being recommended in many settings. High oxygen levels have also been linked to increased oxidative stress in the body.
In this study, we aim to investigate whether monitoring ORI during extubation can help us detect and prevent both hyperoxemia and hypoxemia-situations that standard pulse oximetry often misses. We plan to compare two groups of patients: one receiving conventional 100% oxygen during extubation, and another receiving 80% oxygen. By monitoring ORI values in both groups, we hope to better understand how different oxygen levels affect patient safety and outcomes.
- Conditions
- Laparoscopic Colorectal Surgery
- Being tested
- Oxygen Administration During Extubation
- Keywords
- ORİ, FİO2, laparoscopic colorectal surgery, extubation, pao2
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Oxygen Administration During ExtubationBehavioural
This intervention involves the administration of oxygen during tracheal extubation in patients undergoing laparoscopic surgery. Two different oxygen concentrations are compared: the control group receives 100% oxygen, while the study group receives 80% oxygen during the extubation phase. All patients are monitored using the Oxygen Reserve Index (ORI) to assess oxygenation status continuously. The goal is to evaluate the effect of oxygen concentration on peri-extubation hyperoxia and hypoxia, as detected by ORI values. The intervention is non-invasive and administered via standard anesthesia breathing systems.
| Study group | Role | What they receive |
|---|---|---|
| Group 1 - 100% Oxygen Group | Patients in this group will receive 100% oxygen during tracheal extubation in laparoscopic colorectal surgery. Oxygenation will be monitored continuously using the Oxygen Reserve Index (ORI) and arterial PaO₂. The intervention is non-invasive and administered via standard anesthesia breathing systems. Receives: Behavioral: Oxygen Administration During Extubation | |
| Group 2 - 80% Oxygen Group | Patients in this group will receive 80% oxygen during tracheal extubation in laparoscopic colorectal surgery. Oxygenation will be monitored continuously using the Oxygen Reserve Index (ORI) and arterial PaO₂. The intervention is non-invasive and administered via standard anesthesia breathing systems. Receives: Behavioral: Oxygen Administration During Extubation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Oxygen Reserve Index (ORI ) at 60 minutes post-extubation
Oxygen Reserve Index (ORI) will be continuously monitored using a Masimo Radical-7 pulse co-oximeter from the time of extubation until 60 minutes post-extubation. The ORI value recorded at the 60th minute after tracheal extubation will be used for primary outcome analysis.
Measured: ORI will be recorded at 60 minutes post-extubation using a Masimo Radical-7 pulse co-oximeter to assess peri-extubation oxygen reserve.
Secondary outcomes (6)
Peripheral Oxygen Saturation (SpO₂, %) trends during and after extubation
Measured: Continuous monitoring during and up to 60 minutes after tracheal extubation
Arterial oxygen partial pressure (PaO₂, mmHg) at 5 minutes post-extubation
Arterial blood gas analysis will be performed to measure PaO₂ and evaluate early postoperative oxygenation status following extubation.
Measured: 5 minutes after tracheal extubation
Oxygen Reserve Index (ORI) at 5 minutes post-extubation
ORI will be continuously monitored from extubation until 60 minutes post-extubation using a Masimo Radical-7 device. The ORI value at the 5th minute will be recorded to assess sustained postoperative oxygen reserve.
Measured: 5 minutes after tracheal extubation
Arterial oxygen partial pressure (PaO₂, mmHg) at 60 minutes post-extubation
Arterial blood gas analysis will be used to measure PaO₂ at 60 minutes post-extubation to evaluate sustained oxygenation differences between study groups.
Measured: 60 minutes after tracheal extubation
Heart rate during the first postoperative hour
Heart rate will be continuously monitored to evaluate hemodynamic stability during emergence and the early postoperative period.
Measured: From extubation until 60 minutes post-extubation
Mean arterial pressure (mmHg) during the first postoperative hour
Mean arterial pressure will be continuously monitored to assess hemodynamic changes during emergence and the early postoperative period.
Measured: From extubation until 60 minutes post-extubation
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted3 Mar 2026
- Study start7 Jan 2025
- Primary completion30 Dec 2025
- Study completion10 Feb 2026
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Laparoscopic Colorectal SurgeryStudies 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
- Cohort
- Time perspective
- Prospective
- Enrolment
- 60 participants (actual)
Sponsor and investigators
- Lead sponsor
- Dr. Lutfi Kirdar Kartal Training and Research Hospital
- Sponsor type
- Other government
- Responsible party
- Principal investigator, Türker Kan Taşcı, Dr. Lutfi Kirdar Kartal Training and Research Hospital
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07445698
- Sponsor's protocol ID
- 2025/01/990
- Status last verified
- Feb 2026
- First submitted
- 19 Sep 2025
- Last updated
- 10 Aug 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Undecided
Study at a glance
From the registry record, last updated by the sponsor on 10 Aug 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Comparison of the Effects of 100% and 80% Oxygen Use During Extubation on Oxygen Reserve Index in Laparoscopic Colorectal Surgery
- ClinicalTrials.gov ID
- NCT07445698
- Acronym / sponsor ID
- 2025/01/990
- Conditions
- Laparoscopic Colorectal Surgery
- Keywords
- ORİ, FİO2, laparoscopic colorectal surgery, extubation, pao2
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 60 participants (actual)
- Lead sponsor
- Dr. Lutfi Kirdar Kartal Training and Research HospitalOther government
- Study start
- 7 Jan 2025 (actual)
- Primary completion
- 30 Dec 2025 (actual)
- Study completion
- 10 Feb 2026 (actual)
- First posted
- 3 Mar 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.
During laparoscopic procedures, certain physiological changes occur due to the creation of pneumoperitoneum. One such change is the reduction in portal venous blood flow, which can lead to decreased liver perfusion and acute liver cell injury. Additionally, due to an increased alveolar-arterial oxygen pressure gradient, postoperative atelectasis may occur, leading to hypoxia.
In other words, the increased intra-abdominal pressure during laparoscopic surgery-along with the effects of patient positioning and mechanical ventilation used during anesthesia-can worsen low blood oxygen levels, especially in patients with already reduced lung compliance and higher metabolic demands. This makes close monitoring of oxygenation crucial.
The Oxygen Reserve Index (ORI) is a relatively new tool that can help monitor both high oxygen levels (hyperoxemia) and drops in oxygen (desaturation) before they become clinically apparent. Studies have shown that ORI values range from 0 to 1, with an ORI of 0 typically corresponding to a PaO₂ level between 80-125 mmHg. A downward trend in ORI can act as an early warning sign of hypoxemia, giving clinicians a chance to act before it's too late.
Many studies have highlighted the potential harms of using high oxygen concentrations during surgery. For example, while most hospitals still give patients 100% oxygen before anesthesia (a process called preoxygenation), recent evidence suggests this might increase the risk of atelectasis. Therefore, using 80% or less oxygen is now being recommended in many settings. High oxygen levels have also been linked to increased oxidative stress in the body.
In this study, we aim to investigate whether monitoring ORI during extubation can help us detect and prevent both hyperoxemia and hypoxemia-situations that standard pulse oximetry often misses. We plan to compare two groups of patients: one receiving conventional 100% oxygen during extubation, and another receiving 80% oxygen. By monitoring ORI values in both groups, we hope to better understand how different oxygen levels affect patient safety and outcomes.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Group 1 - 100% Oxygen Group | – | Behavioral: Oxygen Administration During ExtubationPatients in this group will receive 100% oxygen during tracheal extubation in laparoscopic colorectal surgery. Oxygenation will be monitored continuously using the Oxygen Reserve Index (ORI) and arterial PaO₂. The intervention is non-invasive and administered via standard anesthesia breathing systems. |
| Group 2 - 80% Oxygen Group | – | Behavioral: Oxygen Administration During ExtubationPatients in this group will receive 80% oxygen during tracheal extubation in laparoscopic colorectal surgery. Oxygenation will be monitored continuously using the Oxygen Reserve Index (ORI) and arterial PaO₂. The intervention is non-invasive and administered via standard anesthesia breathing systems. |
Who may qualify
- Ages
- 18 to 75 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Sixty volunteer patients, aged between 18 and 75, with a Body Mass Index (BMI) below 35 and ASA class I-III, who are scheduled to undergo elective laparoscopic colorectal surgery , will be included.
Key inclusion criteria (4 listed)
- Age: 18-75
- ASA: I-III
- Scheduled for elective laparoscopic surgery
- BMI <35
Key exclusion criteria (13 listed)
- Patients undergoing emergency surgery due to trauma
- Patients with ASA physical status classification IV or higher
- Patients requiring intensive care unit admission
- Patients with active, clinically symptomatic anemia
- Patients with heart failure
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 |
|---|---|---|
| Oxygen Administration During ExtubationThis intervention involves the administration of oxygen during tracheal extubation in patients undergoing laparoscopic surgery. Two different oxygen concentrations are compared: the control group receives 100% oxygen, while the study group receives 80% oxygen during the extubation phase. All patients are monitored using the Oxygen Reserve Index (ORI) to assess oxygenation status continuously. The goal is to evaluate the effect of oxygen concentration on peri-extubation hyperoxia and hypoxia, as detected by ORI values. The intervention is non-invasive and administered via standard anesthesia breathing systems. | Behavioural | Group 1 - 100% Oxygen Group, Group 2 - 80% Oxygen Group |
Primary outcome
Oxygen Reserve Index (ORI ) at 60 minutes post-extubation
Time frame: ORI will be recorded at 60 minutes post-extubation using a Masimo Radical-7 pulse co-oximeter to assess peri-extubation oxygen reserve.
Oxygen Reserve Index (ORI) will be continuously monitored using a Masimo Radical-7 pulse co-oximeter from the time of extubation until 60 minutes post-extubation. The ORI value recorded at the 60th minute after tracheal extubation will be used for primary outcome analysis.
6 secondary outcomes
Peripheral Oxygen Saturation (SpO₂, %) trends during and after extubation
Time frame: Continuous monitoring during and up to 60 minutes after tracheal extubation
Arterial oxygen partial pressure (PaO₂, mmHg) at 5 minutes post-extubation
Time frame: 5 minutes after tracheal extubation
Oxygen Reserve Index (ORI) at 5 minutes post-extubation
Time frame: 5 minutes after tracheal extubation
Arterial oxygen partial pressure (PaO₂, mmHg) at 60 minutes post-extubation
Time frame: 60 minutes after tracheal extubation
Heart rate during the first postoperative hour
Time frame: From extubation until 60 minutes post-extubation
Mean arterial pressure (mmHg) during the first postoperative hour
Time frame: From extubation until 60 minutes post-extubation
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 10 Aug 2026.
- Individual participant dataSharing planned: Undecided
Related trials for Laparoscopic Colorectal Surgery
RecruitingPhase 3
Intravenous Lidocaine Plus Port-Site Ropivacaine for Recovery After Laparoscopic Surgery
Intravenous Lidocaine, Laparoscopic Surgery
Recruiting
Quality of Recovery After Colorectal Surgery (Robots vs Laparoscopic)
Recovery Outcomes
Recruiting
Effect of Oral Laxative Use Before Colorectal Surgery on Intraoperative Surgical Difficulty
Colorectal Diseases, Mechanical Bowel Preparation
Active, not recruitingPhase 1/2
Opioid-Free Anesthesia in Colorectal Surgery, 2025 (OFA-CRC-2025)
Pain Management, Colorectal Surgery
RecruitingObservational study
Internal Jugular Vein Collapsibility Index as a Predictor of Hypotension
Intraoperative Hypotension
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 Laparoscopic Colorectal Surgery, run by Dr. Lutfi Kirdar Kartal 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 4 inclusion and 13 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 10 Aug 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?
Oxygen Reserve Index (ORI ) at 60 minutes post-extubation (time frame: ORI will be recorded at 60 minutes post-extubation using a Masimo Radical-7 pulse co-oximeter to assess peri-extubation oxygen reserve.). 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 10 Aug 2026.