PROtective Ventilation With FLOW-Controlled Ventilation

NCT06703814 | Recruiting

• 1 other identifier: PROFLOW-ROBOTic pilot
• Study Type: interventional
• Target: 100
• Locations: 3 countries
• Sites: 3

Brief Summary

The investigators want to investigate in patients undergoing robot-assisted laparoscopic surgery (a minimally invasive procedure) how applicable flow-controlled ventilation is, and whether it might also be safer than the current ventilation techniques, as well as its impact on potentially reducing the risk of lung-specific complications. Flow-controlled ventilation has already been tested in several studies on animals and humans and has proven to be a safe form of ventilation for patients undergoing surgery under general anesthesia. When patients undergo major surgery, general anesthesia is required and, as a result, mechanical ventilation of the lungs. Especially in long and complex surgeries, ventilation can become more difficult or lead to complications postoperatively. These patients may then experience shortness of breath, coughing, or require medication to improve lung function. In some cases, reintubation or additional mechanical ventilation may be necessary for support. Previous human studies have shown that flow-controlled ventilation is less stressful and, therefore, potentially safer for the lungs compared to traditional ventilation techniques, and that less supplemental oxygen is required. This effect and the safety of flow-controlled ventilation have been demonstrated in several studies. Therefore, in this study, the investigators aim to explore whether flow-controlled ventilation is potentially safer and easier to apply than traditional ventilation techniques and whether it can reduce the risk of lung-specific complications following robot-assisted surgeries, thereby improving the recovery process postoperatively.

Conditions

Postoperative Pulmonary Complications (PPCs); Feasibility Studies; Pilot Study

Keywords

flow-controlled ventilation; postoperative pulmonary complications; mechanical ventilation; intraoperative ventilation

Outcome Measures

Primary Outcomes (1)

• Safety of intraoperative FCV

  The primary objective of this pilot trial is to evaluate the safety of intraoperative FCV in patients undergoing robot-assisted laparoscopic surgery. Herein the investigators focus on, gas exchange, including both oxygenation and decarboxylation; minute ventilation, during all phases of intraoperative ventilation; key ventilator settings and ventilation parameters; respiratory complications, including pneumothorax and hemodynamic complications, including hypotension and arrhythmias.

  After induction of general anesthesia and beginning of intraoperative mechanical ventilation to the end of surgery and the end of mechanical ventilation (up to a duration of 12 hours of mechanical ventilation).

Secondary Outcomes (1)

• feasibility of intraoperative FCV, study protocol and database completeness

  After induction of general anesthesia and beginning of intraoperative mechanical ventilation to the seventh postoperative day or until end of hospitalization, whatever comes first (i.e., up to 7 days after surgery)

Other Outcomes (1)

• Explorative objective incidence of PPC

  After induction of general anesthesia and beginning of intraoperative mechanical ventilation to the seventh postoperative day or until end of hospitalization, whatever comes first (i.e., up to 7 days after surgery)

Study Arms (2)

Intraoperative flow-controlled ventilation FCV

EXPERIMENTAL

Flow-controlled ventilation (FCV) differs from conventional ventilation modes in several key ways. Unlike pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV), FCV maintains a constant airflow during both the inspiration and expiration phases. This method generates smooth linear pressure variations by delivering a constant positive flow during inspiration and a constant negative flow during expiration, resulting in linearly changing airway pressures. Additionally, FCV operates without any interruptions in flow throughout the cycle. This consistent rate of pressure and volume change in the lungs, particularly the linear decrease in airway pressure during expiration, has been shown to improve lung recruitment. This approach may thus reduce the risk of pulmonary complications commonly associated with conventional ventilation modes.

Other: Intraoperative flow-controlled ventilation strategy

Intraoperative pressure-controlled ventilation PCV

ACTIVE COMPARATOR

Pressure-controlled ventilation (PCV) is the standard of care in patients undergoing mechanical ventilation during general anesthesia in robot-assisted laparoscopic surgery. The operator sets the inspiratory pressure (rather than tidal volume as in VCV) and respiratory rate (along with FiO2, I:E ratio and PEEP). Typically, the pressure is titrated to achieve a targeted tidal volume.

Other: Intraoperative pressure-controlled ventilation strategy

Interventions

Intraoperative flow-controlled ventilation strategy OTHER

In the FCV group, intraoperative ventilation will be provided with the EVONE (IES Ventinova Medical).PEEP and Ppeak are titrated guided by dynamic compliance, as follows: Starting from a default setting of 5 cmH2O of PEEP and 15 cmH2O of Ppeak, PEEP and Ppeak are equally increased by 1 cmH2O steps and the PEEP value with the highest VT and thus highest dynamic compliance is defined as "best" PEEP. Subsequently, Ppeak is stepwise (+1 cmH2O) increased until there is no further over-proportional increase in tidal volume (VT) (i.e. measured VT \> expected VT according to measured dynamic compliance), defined as best driving pressure. No recruitment maneuvers are carried out during FCV. With the I:E ratio set to 1:1, flow is adjusted to establish normocapnia (target etCO2 4.5 to 5.8 kPa). FiO2 is adjusted to maintain oxygen saturation (SpO2) \> 92%.

Also known as: FCV

Intraoperative flow-controlled ventilation FCV

Intraoperative pressure-controlled ventilation strategy OTHER

In the PCV group, intraoperative ventilation will be provided by a standard anesthesia ventilator in use in the respective participating centers. Patients will be ventilated in PCV mode, at the lowest inspired oxygen fraction (FiO2), to maintain oxygen saturation (SpO2) \> 92%. It is left to the discretion of the attending anesthesiologist to use a higher fraction of FiO2. Inspiratory to expiratory ratio is set at 1:1 to 1:2, respiratory rate will be adjusted to target normocapnia (target etCO2 4.5 to 5.8 kPa. VT will be set at 7 to 9 ml/kg predicted body weight (PBW). The PBW is calculated according to a predefined formula: 50 + 0.91 x (centimeters of height - 152.4) for males and 45.5 + 0.91 x (centimeters of height - 152.4) for females. Ventilation starts with 5 cm H2O PEEP, and can be increased to 10 cm H2O PEEP.

Also known as: PCV

Intraoperative pressure-controlled ventilation PCV

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• undergoing elective robot-assisted laparoscopic surgery in supine or Trendelenburg position (either abdominal, urologic or gynecologic surgery);
• AND increased risk of PPCs according to the ARISCAT risk score (≥ 26 points);
• OR the combination of age \> 40 years, scheduled surgery lasting \> 2 hours and planned to receive an intra-arterial catheter for blood pressure monitoring during the surgery;
• aged ≥ 18 years; and
• able to give written informed consent to participate in the study and agree to comply with the study protocol prior to initiation of any study-mandated procedure and study intervention.

You may not qualify if:

• ideal body weight \< 40 kg;
• ASA Physical Status Classification System score IV - VI;
• previous enrolment into the current study;
• being the study investigator, his/her family members, employees and other dependent persons;
• if female and of childbearing potential, known pregnancy or a positive urine pregnancy test (confirmed by a positive serum pregnancy test), or lactating; or
• No informed consent

Sponsors & Collaborators

• Cantonal Hospital of St. Gallen: lead
• University Hospital Bergmannsheil Bochum: collaborator
• Medical University Innsbruck: collaborator

Study Sites (3)

Department of Anaesthesiology, Medical University Innsbruck

Innsbruck, Tyrol, 6020, Austria

RECRUITING

Department of Anesthesiology, Intensive Care and Pain Medicine, BG University Hospital Bergmannsheil, Ruhr-University Bochum, Germany

Bochum, Germany, 44789, Germany

COMPLETED

Department of Anaesthesiology, Rescue- and Pain Medicine Cantonal Hospital St. Gallen

Sankt Gallen, Canton of St. Gallen, 9000, Switzerland

COMPLETED

Study Officials

• Timur Yurttas, MD

  Department of Anesthesiology, Rescue- and Painmedicine, Cantonal Hospital St. Gallen, Switzerland

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Timur Yurttas, MD

CONTACT

+41714949158; proflow@kssg.ch

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: MD

Model Details: intraoperative Flow-controlled ventilation versus intraoperative pressure-controlled ventilation during general anesthesia

Study Record Dates

• First Submitted: November 19, 2024
• First Posted: November 25, 2024
• Study Start: August 2, 2025
• Primary Completion: April 30, 2026
• Study Completion (Estimated): May 31, 2026
• Last Updated: April 21, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

CH (1); DE (1); AU (1)