An observational study in One-lung Ventilation (OLV), sponsored by Ankara Ataturk Sanatorium Training and Research Hospital. Not yet recruiting at 1 site in Turkey (Türkiye). Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-02-02.
Sponsored by Ankara Ataturk Sanatorium Training and Research Hospital · Observational
One-lung ventilation is commonly used during thoracic surgery but is frequently associated with impaired oxygenation and altered respiratory mechanics. Traditional oxygenation indices require arterial blood gas analysis and do not fully reflect the mechanical stress applied to the lungs.
This prospective observational study aims to evaluate the correlation between oxygenation indices and oxygen saturation indices during one-lung ventilation in adult patients undergoing elective thoracic surgery. Modified indices incorporating driving pressure and mechanical power will also be assessed.
No intervention beyond standard clinical care will be applied. The findings of this study may help clarify the clinical utility of non-invasive oxygenation indices for intraoperative monitoring during one-lung ventilation.
One-lung ventilation induces complex changes in pulmonary physiology, including increased intrapulmonary shunt and altered respiratory mechanics, which may challenge conventional approaches to intraoperative oxygenation assessment. While invasive oxygenation indices are widely used, their applicability during one-lung ventilation is limited by the need for arterial blood gas sampling and the lack of integration of mechanical ventilation-related stress.
Non-invasive oxygen saturation-based indices have been proposed as alternatives; however, data regarding their performance under the dynamic physiological conditions of one-lung ventilation remain scarce. Furthermore, emerging concepts in lung-protective ventilation emphasize the importance of driving pressure and mechanical power as determinants of ventilator-induced lung injury, yet these parameters are not incorporated into traditional oxygenation metrics.
In this prospective observational study, invasive and non-invasive oxygenation indices, including modified forms incorporating driving pressure and mechanical power, will be recorded simultaneously during one-lung ventilation in adult patients undergoing elective thoracic surgery. The relationships and agreement between these indices will be analyzed to assess their comparability across different levels of mechanical respiratory load.
No intervention beyond standard clinical care will be applied. Ventilatory settings and perioperative management will be determined solely by routine clinical practice. This study is designed to provide methodological insight into the intraoperative applicability of non-invasive oxygenation indices during one-lung ventilation.
Adult patients aged 18 years and older with ASA physical status I-III who are scheduled for elective thoracic surgery requiring intraoperative one-lung ventilation for at least one hour. All participants undergo standard perioperative management with simultaneous arterial blood gas analysis and continuous pulse oximetry monitoring during surgery.
Exclusion Criteria:
Adult patients undergoing elective thoracic surgery requiring one-lung ventilation. All patients will be managed according to standard clinical practice. No intervention is assigned as part of this observational study.
Correlation between oxygenation indices and oxygen saturation indices
Correlation between invasive oxygenation indices (oxygenation index and its derivatives) and non-invasive oxygen saturation indices (oxygen saturation index and its derivatives) measured during one-lung ventilation.
Time frame: During intraoperative one-lung ventilation
Plan to share: No
This study is not yet recruiting, as verified in Jan 2026. You cannot join it, but the record below documents what was studied.
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Ankara Ataturk Sanatorium Training and Research Hospital