Flow Controlled Ventilation in Thoracic Surgery

Flow-controlled ventilation (FCV) is a novel ventilation method with promising first results in porcine studies as well as clinical cross-over trials. A more efficient and maybe lung protective ventilation strategy would be crucial in the challenging situation of one lung ventilation during thoracic surgery, when the whole gas exchange has to be provided by just one half of the lungs.

Thus, individualized FCV, based on compliance guided pressure settings, will be compared to standard of pressure-controlled ventilation in thoracic surgery requiring one lung ventilation in a randomized controlled trial. Based on previous preclinical trials an improvement of oxygenation by 15% will be expected and in order to transfer the preclinical results to humans oxygenation assessed by paO2 / FiO2 ratio after 30 minutes of one lung ventilation is the main primary outcome parameter of this study. Furthermore, improved recruitment of lung tissue due to controlled expiratory flow in FCV will be anticipated without the need of recruitment maneuvers, which may cause deleterious effects on lung tissue. Accordingly any recruitment maneuvers will be omitted in the FCV group.

The investigators hypothesize that improved gas exchange in terms of improved oxygenation and reduced respiratory minute volume required for CO2-removal will be achieved with FCV compared to PCV. Secondary outcome parameters such as the incidence of postoperative pulmonary complications will be additionally assessed in order to plan future studies with clinically relevant outcome.

Inclusion criteria

• Male and female subjects ≥ 18 years
• Body weight ≥ 40 kg
• Elective thoracic surgery requiring OLV
• ASA I-III
• Written informed consent

Exclusion criteria

• Emergency surgery
• Female subjects known to be pregnant
• Known participation in another interventional clinical trial
• high pulmonary risk (ppo FEV1<20ml/kg in male or ppo FEV1<18ml/kg in female)
• Empyema evacuation or signs of pulmonary infection
• High grade CMP (EF<30%)