Positive-Pressure Respiration, Intrinsic
Conditions
Keywords
flow controlled ventilation, pressure controlled ventilation, thoracic surgery, one lung ventilation
Brief summary
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.
Detailed 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.
Sponsors
Medical University Innsbruck
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
controlled, prospective
Eligibility
Sex/Gender
ALL
Age
18 Years to 99 Years
Healthy volunteers
No
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%)
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| paO2 / FiO2 ratio (Horowitz Index) | after 30 minutes of one lung ventilation | Comparison of oxygenation assessed by arterial partial pressure of oxygen (paO2) / fraction of inspired oxygen (FiO2) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| venous admixture (Qs / Qt) | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of calculated venous admixure from arterial and central venous blood gas analysis |
| respiratory minute volume | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of respiratory minute volume |
| respiratory rate | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of respiratory rate |
| tidal volume | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of applied tidal volume |
| positive end-expiratory pressure | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of set positive end-expiratory pressure |
| peak pressure | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of set peak pressure |
| driving pressure | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of resulting driving pressure |
| respiratory compliance | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of measured respiratory compliance |
| decarboxylation (paCO2) | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Required respiratory minute volume to achieve a taregeted paCO2 of 35-45 mmHg during two lung ventilation and 40-60 mmHg during one lung ventilation |
| respiratory resistance | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of measured respiratory resistance |
| heart rate | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of measured heart rate |
| mean arterial pressure | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of measured mean arterial pressure |
| central venous pressure | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of measured central venous pressure |
| Concentration of plamatic cytokine levels | preoperative before induction of general anesthesia and postoperative at PACU admission and 1 hour thereafter | Plasmatic cytokine level of IL-6, IL-8, IL-10 and TNF-alpha will be assessed pre- (before induction of general anesthesia) and postoperative (ad PACU admission and 60 minutes therafter). |
| length of PACU stay | Time from PACU admission to transfer to a general ward in hours | Duration of the patient at the post-anesthesia care unit (PACU) |
| length of hospital stay | days from surgery to hospital discharge | Comparison of length of hospital stay after thoracic surgery |
| postoperative pulmonary complications (PPC) | until hospital discharge or day 30 of hospital stay | PPC will be assessd daily until hospital discharge or day 30 of hospital stay from the medical records during the follow-up period. The European Perioperative Clinical Outcome (EPCO) definition will be used to assess the occurrence of PPC. |
| applied mechanical power | during two lung ventilation in supine position after anesthesia induction (T1) and change to lateral position (T2), after 15 (T3), 30 (T4) and 60 minutes (T5) of one lung ventilation and after reinflation before tracheal extubation (T6) | Comparison of calculated applied mechanical power from the ventilator |
Countries
Austria
Outcome results
None listed