Flow Controlled Ventilation in Thoracic Surgery

Medical University Innsbruck

Status: Completed

Conditions: Positive-Pressure Respiration, Intrinsic

Treatments: Device: Evone; Device: Primus

Study type: Interventional

Funder types: Other

Identifiers

NCT04534933

1014/2020

Details and patient eligibility

About

This trial investigates effects of individualized (by compliance guided pressure settings) flow-controlled ventilation compared to best clinical practice pressure-controlled ventilation in thoracic surgery requiring one lung ventilation.

Full description

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.

Enrollment: 46 patients

Sex: All

Ages: 18 to 99 years old

Volunteers: No Healthy Volunteers

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%)

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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46 participants in 2 patient groups

FCV

Experimental group

Description:

Artificial ventilation will be performed with individualized flow-controlled ventilation (Evone, Ventinova Medical B.V., Eindhoven, the Netherlands) during thoracic surgery. Individualization will be established by compliance guided end-expiratory and peak pressure setting during two lung ventilation as well as one lung ventilation, flow setting will be adjusted to secure normocapnia during two lung ventilation and the targeted paCO2 during one lung ventilation is 40-60 mmHg, provided that pH \>7.2. The I:E ratio will be set to 1:1. The FiO2 will be set to achieve normoxia during two lung ventilation, increased to 100% before lung isolation and after 15 minutes of one-lung ventilation again decreased to secure normoxia or mild hyperoxia (target paO2 of 75-120 mmHg). No recruitment maneuver will be performed for re-inflation of the separated lung and after regain of spontaneous breathing tracheal extubation performed in the operating room.

Treatment:

Device: Evone

PCV

Active Comparator group

Description:

Artificial ventilation will be performed with pressure-controlled ventilation (Primus, Dräger, Lübeck, Germany) during thoracic surgery. Peak pressure will be set to achieve a tidal volume of 6-8 ml/kg predicted body weight (PBW) at a compliance titrated positive end-expiratory pressure during two lung ventilation and the tidal volume will be reduced to 4-6 ml/kg PBW during one lung ventilation. Respiratory rate will be set to maintain normocapnia during two lung ventilation and a targeted paCO2 level during one lung ventilation of 40-60 mmHg, provided that pH \> 7.2. The I:E ratio will be set to 1:1.5 except extension of expiration is necessary in order to avoid air trapping. The FiO2 will be set to achieve normoxia during two lung ventilation, increased to 100% before lung isolation until 15 minutes of one lung ventilation and decreased thereafter to achieve a targeted paO2 level of 75-120 mmHg. For re-inflation a manual recruitment maneuver will be performed under surgical guidance.

Treatment:

Device: Primus