Clinical Research Directory

Comparison of FCV and VCV in One-Lung Ventilation

One-lung ventilation (OLV) is commonly used during thoracic surgery but may negatively affect lung mechanics and gas exchange. Different ventilation strategies are used during OLV, and their effects on respiratory parameters remain an important clinical concern. Flow-controlled ventilation (FCV) is a newer ventilation mode that allows precise control of inspiratory and expiratory flow, potentially improving lung mechanics and gas exchange. Volume-controlled ventilation (VCV) is a widely used conventional ventilation strategy during thoracic anesthesia. The FCVOLVent study is a multicenter, prospective observational study designed to compare the effects of FCV and VCV during one-lung ventilation in adult patients undergoing thoracic surgery. Patients will be ventilated with either FCV or VCV as part of routine clinical practice. The study aims to evaluate respiratory mechanics and oxygenation parameters, including the PaO₂/FiO₂ ratio, airway pressures, lung compliance, and mechanical power during surgery. Data will be collected at predefined time points during one-lung ventilation. The results of this study are expected to provide real-world clinical evidence on the potential advantages and limitations of flow-controlled ventilation compared with volume-controlled ventilation during one-lung ventilation.

Individualized Open Lung Ventilation and Postoperative Pulmonary Complications in Thoracic Surgery

This prospective, single-center, randomized controlled trial aims to evaluate the efficacy of an intraoperative "Individualized Open Lung Ventilation" strategy compared to a standard lung-protective ventilation strategy in patients undergoing thoracic surgery. One-lung ventilation (OLV) is essential for thoracic surgery but can cause lung injury. While standard care often uses fixed ventilation parameters, this study investigates whether personalizing Positive End-Expiratory Pressure (PEEP) to achieve the lowest driving pressure can reduce the incidence of postoperative pulmonary complications (PPCs) within 7 days after surgery.

Correlation of Oxygenation and Saturation Indices in One-Lung Ventilation

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.

The Role of Existing Formulas in the Double-lumen Tube in Thoracic Surgery Anesthesia

In most clinical scenarios, left DLT is preferred for one-lung ventilation because of its anatomical ease of placement; these tubes allow separate ventilation of both lungs. If the DLT is not placed in the proper size and depth, it may result in repeated intubation attempts, airway and dental trauma, failed lung isolation, tube dislodgement, and various unwanted events such as hypoxemia. The first and most common method for correct placement of a DLT is the conventional technique, blindly advanced into the left main bronchus, and then confirmed with fiberoptic bronchoscopy (FOB). In this method, the depth at which the tube should be left before performing FOB is left to the clinician's experience. Generally, the DLT is advanced in the trachea until a slight resistance is felt. This may lead to excessive advancement of the DLT into the left main bronchus or premature resistance due to the tube tip touching the carina, causing the clinician to stop before entering the left main bronchus. Therefore, just as selecting the correct size of the DLT is crucial, correctly estimating the appropriate depth is also of great importance. For this reason, different formulas have been proposed in the literature, and new formulas are still being investigated. The patient's gender and height are determinant in selecting the appropriate size of the DLT. However, studies in the literature indicate that the accuracy of these formulas may be limited in Asian populations. Therefore, it is important to evaluate the applicability of these formulas in different populations and, if necessary, develop new formulas. In the Turkish population as well, verifying the accuracy of these formulas for determining the proper size and depth of DLT-and if needed, developing new recommendations and formulas-holds clinical importance. In this study, conducted at Ankara Atatürk Sanatorium Training and Research Hospital, the aim is to evaluate the accuracy of six different formulas available in the literature for predicting DLT depth in patients undergoing thoracic surgery. Additionally, the correlations between DLT depth and demographic parameters as well as external airway measurements (mouth opening, sternomental distance, thyromental distance, distance between the mentum and manubrio-sternal angle, distance between tragus and manubrio-sternal angle, distance between sternal angle and xiphoid process) will be analyzed. Furthermore, challenges during DLT application, malposition rates and types, and complications will be assessed. The primary objective of this study is to evaluate, in patients undergoing thoracic surgery at Ankara Atatürk Sanatorium Training and Research Hospital, how accurate and applicable six different formulas defined in the literature are for predicting the placement depth of the DLT. If the existing formulas are insufficient, the aim is to develop a new formula.

Study of Cardiac Power Index During Supine, Lateral, and Between Left and Right Positions During Two- and One-Lung Ventilation (OLV): Comparison of Hemodynamic Changes After Lung Recruitment Maneuver and Fluid Challenge Among Responders and Non-Responders (SVI, MAP, CPI Changes).

The aim of this trial is to study the changes of the Cardiac Power Index (CPI) during supine and lateral decubitus position in two and one lung ventilation respectively. Moreover, CPI variations will be compared among patients in left versus patients in right lateral decubitus position. A secondary goal is to compare the changes in hemodynamic parameters after a lung recruitment maneuver during one lung ventilation and a fluid challenge test among patients that respond (responders) or do not respond to fluids (non-responders) according to changes of Stroke Volume Index (SVI) and Mean Arterial Pressure (MAP).