Flow-Controlled Ventilation to Improve Postoperative Pulmonary Outcome After Thoracic Surgery

Condition(s) studied

Investigational drug(s) / intervention(s)

Flow-Controlled Ventilation: In the FCV group, patients will be ventilated using the EVONE ventilator with dynamic compliance-guided titration of PEEP and driving pressure. Ventilation starts with a PEEP of 5 cmH2O and a Ppeak of 15 cmH2O. Both parameters are increased stepwise to identify the PEEP associated with the highest tidal volume and best dynamic compliance, followed by further adjustment of Ppeak to determine the optimal driving pressure. No recruitment maneuvers are routinely performed. Ventilation is provided with an I:E ratio of 1:1, while flow is adjusted to maintain normocapnia (target etCO2 4.5-5.8 kPa). FiO2 is titrated to maintain SpO2 \>92%. Rescue crossover to conventional VCV is permitted in cases of ventilator malfunction or unresolved impairment of oxygenation, ventilation, or CO2 elimination, at the discretion of the attending anesthesiologist.

Volume-Controlled Ventilation: In the VCV group, intraoperative ventilation will be provided using standard anesthesia ventilators routinely used at the participating centers. Patients will receive lung-protective VCV with tidal volumes of 7-9 ml/kg predicted body weight during two-lung ventilation and 5-6 ml/kg during one-lung ventilation. Respiratory rate and FiO2 will be adjusted to maintain normocapnia (target etCO2 4.5-5.8 kPa) and SpO2 \>92%, with an inspiratory-to-expiratory ratio of 1:1 to 1:2. Ventilation will start with a PEEP of 5 cmH2O, while further adjustments of ventilatory parameters, including PEEP, are left to the discretion of the attending anesthesiologist according to routine clinical practice. Rescue crossover to FCV is not permitted; however, switching to another conventional ventilation mode is allowed in cases of ventilator malfunction or unresolved impairment of oxygenation, ventilation, or CO2 elimination.

Study summary

In an international multicenter randomized clinical pilot trial, intraoperative flow-controlled ventilation (FCV) will be compared with volume-controlled ventilation (VCV) in patients scheduled for (open, video- or robot-assisted) thoracic surgery with one-lung ventilation (OLV). This pilot trial is designed to test the feasibility and safety of FCV during all phases of intraoperative ventilation, and in particular during OLV, and to inform the design of a future trial testing the efficacy of FCV with regard to postoperative outcomes, including postoperative pulmonary complications (PPC).

The ventilation modes are conducted with CE-marked medical devices (anesthesia ventilators or medical ventilators), however these medical devices themselves are not under investigation. All CE-marked standard medical devices from varied manufacturers in use at the participating study centers will be used in full accordance with their instructions for use. FCV has shown safety and feasibility in various surgical settings, including thoracic surgery with OLV, however its feasibility in a multicenter trial has not been investigated yet.

Eligibility

Primary outcome measure(s)

• Feasibility (Proportion of Full Adherence to the Ventilation Protocols) — From enrollment to the end of intraoperative surgical procedures at the day of surgery.
  Outcomes in this pilot study are selected to support the evaluation of feasibility of the ventilation protocols used and study protocol integrity. The primary outcome of this pilot study is a composite of feasibility issues of the ventilation protocols, including * correct use of predefined standard ventilator settings; * correct titration of PEEP and driving pressure (with FCV), and correct PEEP and tidal volume (with VCV); * correct titration of FiO2; * correct respiratory monitoring; * any significant deviation from the predefined standard ventilator settings, beyond pre-approved deviations for safety; and * any significant deviation in ventilator settings based on surgeon's assessment of surgical conditions. At least 80% of patients must receive ventilation according to the study protocol to progress to the future trial.

Trial sites (7)

Other trials for the same condition