One Lung Ventilation in Thoracic Surgery
Conditions
Keywords
One-Lung Ventilation, oxygen reserve index, Hyperoxia, Thoracic surgery, Oxidative stress, Oxygen
Brief summary
One-lung ventilation (OLV) is routinely used during thoracic surgery to facilitate surgical exposure but is associated with an increased risk of intraoperative hypoxemia. To prevent hypoxia, high fractions of inspired oxygen (FiO₂) are commonly administered; however, excessive oxygen delivery may lead to hyperoxia and oxidative tissue injury. The Oxygen Reserve Index (ORi) is a novel, noninvasive monitoring parameter that provides real-time information on moderate hyperoxia and may allow more precise titration of FiO₂ during anesthesia. The aim of this prospective, randomized clinical trial is to evaluate whether ORi-guided intraoperative oxygen management can reduce oxygen exposure during OLV without increasing hypoxemia and to assess its effects on oxidative stress biomarkers and postoperative outcomes. Adult patients undergoing elective thoracic surgery with OLV are randomized to receive either ORi-guided FiO₂ titration or conventional oxygen management. Oxidative stress biomarkers and postoperative pulmonary complications are compared between groups.
Detailed description
One-lung ventilation is an essential component of thoracic anesthesia but poses significant challenges in maintaining adequate oxygenation. In clinical practice, high FiO₂ levels are often applied to prevent hypoxemia; however, prolonged exposure to hyperoxia has been associated with increased oxidative stress, inflammatory responses, and potential tissue damage. Despite growing awareness of oxygen toxicity, optimal intraoperative oxygen titration strategies during OLV remain poorly defined. The Oxygen Reserve Index is derived from multiwavelength pulse oximetry and provides continuous, noninvasive information on moderate hyperoxia (corresponding to arterial oxygen tensions above normoxia but below severe hyperoxia). ORi monitoring may enable anesthesiologists to titrate FiO₂ more precisely, thereby avoiding unnecessary oxygen exposure while maintaining adequate oxygenation. In this prospective, randomized clinical trial, adult patients scheduled for elective thoracic surgery requiring OLV are allocated to either an ORi-monitored group or a control group. In the ORi group, FiO₂ is adjusted intraoperatively according to predefined ORi thresholds, whereas in the control group FiO₂ is managed according to standard clinical practice based on pulse oximetry. Blood and tracheal aspirate samples are collected preoperatively and at predefined postoperative time points to measure interleukin-6, superoxide dismutase, and malondialdehyde levels as markers of inflammation and oxidative stress. Postoperative pulmonary complications and surgical site infections are recorded during intensive care unit and ward follow-up. This study aims to determine whether ORi-guided oxygen titration during OLV can safely reduce intraoperative oxygen exposure and to clarify its impact on biochemical markers of oxidative stress and clinical outcomes such as postoperative pulmonary complications and surgical site infection.
Interventions
DEVICEOxygen Reserve Index (ORi)-guided oxygen titration
FiO₂ adjusted intraoperatively according to predefined ORi thresholds during thoracic surgery and one lung ventilation period.
Sponsors
Gazi University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
A prospective, randomized, parallel-group clinical trial comparing ORi-guided intraoperative FiO₂ titration with conventional oxygen management in adult patients undergoing thoracic surgery with one-lung ventilation.
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
* Patients age between 18-85 years Elective case Thoracic surgeries performed with one-lung ventilation using a double-lumen endotracheal tube Left ventricule ejection fraction(LVEF)\>45%
Exclusion criteria
* heart failure (LVEF) \< 45% severe valvular disease admission as an emergency case history of prior lung resection presence of peripheral arterial disease.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean intraoperative FiO₂ | From anesthesia induction to the extubation | The primary outcome is the mean fraction of inspired oxygen (FiO₂) administered during one-lung ventilation and throughout the entire duration of surgery, recorded continuously intraoperatively and compared between the ORi-guided and conventional oxygen management groups. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Oxidative stress biomarkers (IL-6, SOD, MDA) | Anesthesia induction, extubation, postoperative 12th hour, postoperative 24th hour | Changes in serum and tracheal aspirate levels of interleukin-6, superoxide dismutase, and malondialdehyde assessed at four time points. Serum biomarker levels are measured at anesthesia induction and at the 12th and 24th postoperative hours, while tracheal aspirate biomarker levels are measured at extubation. Results are compared between the ORi and Non-ORİ groups. |
| Postoperative pulmonary complications | up to 2 weeks | Incidence of postoperative pulmonary complications, including prolonged drainage, hemothorax, bronchopleural fistula, reintubation, atelectasis, bronchopneumonia, and acute respiratory distress syndrome, assessed during intensive care unit and ward follow-up. |
| Surgical site infections | up to 2 weeks | Incidence of surgical site infections recorded during postoperative hospital stay. |
Countries
Turkey (Türkiye)
Contacts
PRINCIPAL_INVESTIGATORBuğra Aykenar
Gazi University
Outcome results
None listed