Postoperative SpO₂/FiO₂ Ratio and Analgesic Methods in Laparoscopic Surgery

NCT07401589 | Not Yet Recruiting

• 1 other identifier: 293-2025
• Study Type: observational
• Target: 100
• Locations: 1 country
• Sites: 1

Brief 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. 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

Outcome Measures

Primary Outcomes (1)

• 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.

  Within the first postoperative hour (0-60 minutes after surgery)

Study Arms (2)

Postoperative Observational Cohort

Other: Standard of Care

control

Other: Standard of Care

Interventions

Standard of Care OTHER

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.

Postoperative Observational Cohort; control

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

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.

You may qualify if:

• 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

You may not qualify if:

• 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
• 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

Sponsors & Collaborators

• Istinye University: lead

Study Sites (1)

Istinye Üniversity

Istanbul, Merkez Mahallesi, 34250, Turkey (Türkiye)

Location

Related Publications (2)

• 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.

  PMID: 11094011 BACKGROUND

• Aboseif 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.

  PMID: 37645008 RESULT

MeSH Terms

Interventions

Standard of Care

Intervention Hierarchy (Ancestors)

Quality Indicators, Health Care; Quality of Health Care; Health Services Administration; Health Care Quality, Access, and Evaluation

Central Study Contacts

ilke dolğun

CONTACT

+905555485632; ilkeser2004@gmail.com

Study Design

• Study Type: observational
• Observational Model: CASE CONTROL
• Time Perspective: PROSPECTIVE
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: ass. prof

Study Record Dates

• First Submitted: February 3, 2026
• First Posted: February 10, 2026
• Study Start: February 15, 2026
• Primary Completion: March 15, 2026
• Study Completion: March 31, 2026
• Last Updated: February 10, 2026

Record last verified: 2026-02

Locations

TU (1)