Postoperative HypoxemiaNCT07401589
Postoperative SpO₂/FiO₂ Ratio and Analgesic Methods in Laparoscopic Surgery
An observational study of Postoperative Hypoxemia, run by Istinye University at 1 site in Turkey (Türkiye).
Trial summary
This prospective observational study aims to evaluate the association between postoperative oxygenation, assessed by the SpO₂/FiO₂ ratio, and body mass index (BMI), STOP-BANG score, and postoperative analgesic methods in patients undergoing elective laparoscopic cholecystectomy in the reverse Trendelenburg position. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Postoperative Hypoxemia
- How many people
- 100 participants
- Where
- 1 siteTurkey (Türkiye)
- Study dates
- 15 Feb 2026to 31 Mar 2026
- Phase
- Observational
- 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 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: The study population consists of adult patients aged 18 years and older with ASA physical status I-III who undergo elective laparoscopic cholecystectomy in the reverse Trendelenburg position. All participants provide written informed consent. Patients with significant respiratory or cardiovascular comorbidities, emergency surgery, or perioperative respiratory complications are excluded.
Who may be able to join
- Age ≥ 18 years
- Patients who provide written informed consent
- ASA physical status I-III
- Patients undergoing elective laparoscopic cholecystectomy
- Surgery performed in the reverse Trendelenburg position (30°)
- Expected operative duration < 3 hours
Who cannot join
- Age < 18 years
- Refusal or inability to provide informed consent
- ASA physical status IV or higher
- Known chronic respiratory diseases (e.g., asthma, COPD)
- Severe cardiac failure (NYHA class III-IV) or advanced cardiovascular disease
- Emergency surgery
Show all 10Show fewer
- Preoperative oxygen supplementation or baseline SpO₂ < 90%
- Prolonged intubation or perioperative respiratory complications
- Requirement for postoperative noninvasive ventilation or intensive care unit admission
- Missing SpO₂ or FiO₂ data preventing calculation of the SpO₂/FiO₂ ratio
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
Istinye Üniversity
Istanbul, Merkez Mahallesi, 34250
About this study
Official title: Association of Postoperative SpO₂/FiO₂ Ratio With Body Mass Index, STOP-BANG Score, and Analgesic Methods in Patients Undergoing Laparoscopic Surgery in Reverse Trendelenburg Position
This prospective observational study aims to evaluate the association between postoperative oxygenation, assessed by the SpO₂/FiO₂ ratio, and body mass index (BMI), STOP-BANG score, and postoperative analgesic methods in patients undergoing elective laparoscopic cholecystectomy in the reverse Trendelenburg position. Postoperative SpO₂ and FiO₂ values will be recorded within the first postoperative hour, and the SpO₂/FiO₂ ratio will be calculated. Analgesic techniques applied as part of routine clinical practice will be documented. The study does not involve any additional intervention beyond standard care. The findings are expected to contribute to a better understanding of factors associated with early postoperative oxygenation and hypoxemia risk.
- Conditions
- Postoperative Hypoxemia
- Being tested
- Standard of Care
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Standard of CareOther
No intervention is applied in this study. Patients are managed according to routine clinical practice. Demographic data, body mass index, STOP-BANG score, postoperative analgesic methods, and postoperative SpO₂ and FiO₂ values are recorded, and the SpO₂/FiO₂ ratio is calculated. All data are collected observationally without any additional procedures or changes to standard care.
| Study group | Role | What they receive |
|---|---|---|
| Postoperative Observational Cohort | Not described Receives: Other: Standard of Care | |
| control | Not described Receives: Other: Standard of Care |
What is being measured
The primary outcome is the main question the study is designed to answer.
postoperative SpO₂/FiO₂ Ratio
The SpO₂/FiO₂ ratio calculated using peripheral oxygen saturation (SpO₂) and fraction of inspired oxygen (FiO₂) measured during the early postoperative period to assess postoperative oxygenation.
Measured: Within the first postoperative hour (0-60 minutes after surgery)
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Feb 2026
- Study start15 Feb 2026 (estimated)
- Primary completion15 Mar 2026 (estimated)
- Study completion31 Mar 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Postoperative HypoxemiaStudies of the same condition, open and under way.
- More trials run by Istinye UniversityThe sponsor's other registered studies.
- 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
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Istinye University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, İlke Dolgun, Istinye University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07401589
- Sponsor's protocol ID
- 293-2025
- Status last verified
- Feb 2026
- First submitted
- 3 Feb 2026
- Last updated
- 10 Feb 2026
- Results posted
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
Publications
Perilli V, Sollazzi L, Bozza P, Modesti C, Chierichini A, Tacchino RM, Ranieri R. The effects of the reverse trendelenburg position on respiratory mechanics and blood gases in morbidly obese patients during bariatric surgery. Anesth Analg. 2000 Dec;91(6):1520-5. doi: 10.1097/00000539-200012000-00041.
PubMed 11094011Aboseif A, Bedewy A, Nafei M, Hammad R, Amin S. Effect of Intraoperative Lung Recruitment and Transversus Abdominis Plane Block in Laparoscopic Bariatric Surgery on Postoperative Lung Functions: A Randomized Controlled Study. Anesth Pain Med. 2023 Mar 5;13(2):e128440. doi: 10.5812/aapm-128440. eCollection 2023 Apr.
PubMed 37645008
Study at a glance
From the registry record, last updated by the sponsor on 10 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Association of Postoperative SpO₂/FiO₂ Ratio With Body Mass Index, STOP-BANG Score, and Analgesic Methods in Patients Undergoing Laparoscopic Surgery in Reverse Trendelenburg Position
- ClinicalTrials.gov ID
- NCT07401589
- Acronym / sponsor ID
- 293-2025
- Conditions
- Postoperative Hypoxemia
- Study type
- Observational
- Recruitment status
- Not yet recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Istinye UniversityUniversity, hospital or other
- Study start
- 15 Feb 2026 (estimated)
- Primary completion
- 15 Mar 2026 (estimated)
- Study completion
- 31 Mar 2026 (estimated)
- First posted
- 10 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 prospective observational study aims to evaluate the association between postoperative oxygenation, assessed by the SpO₂/FiO₂ ratio, and body mass index (BMI), STOP-BANG score, and postoperative analgesic methods in patients undergoing elective laparoscopic cholecystectomy in the reverse Trendelenburg position. Postoperative SpO₂ and FiO₂ values will be recorded within the first postoperative hour, and the SpO₂/FiO₂ ratio will be calculated. Analgesic techniques applied as part of routine clinical practice will be documented. The study does not involve any additional intervention beyond standard care. The findings are expected to contribute to a better understanding of factors associated with early postoperative oxygenation and hypoxemia risk.
Study design
- Observational model
- Case-control
- Time perspective
- Prospective
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| Postoperative Observational Cohort | – | Other: Standard of Care |
| control | – | Other: Standard of Care |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- The study population consists of adult patients aged 18 years and older with ASA physical status I-III who undergo elective laparoscopic cholecystectomy in the reverse Trendelenburg position. All participants provide written informed consent. Patients with significant respiratory or cardiovascular comorbidities, emergency surgery, or perioperative respiratory complications are excluded.
Key inclusion criteria (6 listed)
- Age ≥ 18 years
- Patients who provide written informed consent
- ASA physical status I-III
- Patients undergoing elective laparoscopic cholecystectomy
- Surgery performed in the reverse Trendelenburg position (30°)
Key exclusion criteria (10 listed)
- Age < 18 years
- Refusal or inability to provide informed consent
- ASA physical status IV or higher
- Known chronic respiratory diseases (e.g., asthma, COPD)
- Severe cardiac failure (NYHA class III-IV) or advanced cardiovascular disease
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 |
|---|---|---|
| Standard of CareNo intervention is applied in this study. Patients are managed according to routine clinical practice. Demographic data, body mass index, STOP-BANG score, postoperative analgesic methods, and postoperative SpO₂ and FiO₂ values are recorded, and the SpO₂/FiO₂ ratio is calculated. All data are collected observationally without any additional procedures or changes to standard care. | Other | Postoperative Observational Cohort, control |
Primary outcome
postoperative SpO₂/FiO₂ Ratio
Time frame: Within the first postoperative hour (0-60 minutes after surgery)
The SpO₂/FiO₂ ratio calculated using peripheral oxygen saturation (SpO₂) and fraction of inspired oxygen (FiO₂) measured during the early postoperative period to assess postoperative oxygenation.
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 10 Feb 2026.
- Background: PubMed 11094011Perilli V, Sollazzi L, Bozza P, Modesti C, Chierichini A, Tacchino RM, Ranieri R. The effects of the reverse trendelenburg position on respiratory mechanics and blood gases in morbidly obese patients during bariatric surgery. Anesth Analg. 2000 Dec;91(6):1520-5. doi: 10.1097/00000539-200012000-00041.
- Results publication: PubMed 37645008Aboseif A, Bedewy A, Nafei M, Hammad R, Amin S. Effect of Intraoperative Lung Recruitment and Transversus Abdominis Plane Block in Laparoscopic Bariatric Surgery on Postoperative Lung Functions: A Randomized Controlled Study. Anesth Pain Med. 2023 Mar 5;13(2):e128440. doi: 10.5812/aapm-128440. eCollection 2023 Apr.
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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.
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 Postoperative Hypoxemia, run by Istinye 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 6 inclusion and 10 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 10 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 ilke dolğun (+905555485632, ilkeser2004@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
postoperative SpO₂/FiO₂ Ratio (time frame: Within the first postoperative hour (0-60 minutes after surgery)). 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 NCT07401589, which also lists 2 linked publications.
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 Feb 2026.