Cardiac Surgery, Mechanical Ventilation After Surgery
Conditions
Brief summary
Airway opening pressure is a key parameter in assessing respiratory mechanics. Current practice primarily relies on indirect assessments of lung mechanics, but growing evidence suggests that direct airway opening pressure measurement could enhance individualized ventilatory strategies. Significant airway opening pressure suggests incomplete alveolar recruitment at end-expiration, which may contribute to ventilation-perfusion mismatch, increased respiratory effort, and postoperative pulmonary complications such as atelectasis and impaired gas exchange. Determining the prevalence and clinical relevance of significant airway opening pressure in post-cardiac surgery patients could contribute to more personalized respiratory strategies and improve postoperative care.
Interventions
DIAGNOSTIC_TESTAirway opening pressure
Airway opening pressure will be measured within one hour of intensive care unit admission (using a standardized low-flow insufflation maneuver flow 5-6 LPM). The inflection point on the pressure-time or pressure-volume waveform- depending on ventilator model-will define the airway opening pressure.
Sponsors
Laval University
Study design
Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
DIAGNOSTIC
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Months to No maximum
Healthy volunteers
No
Inclusion criteria
* Adult (≥18 years) * Undergoing elective coronary artery bypass grafting (CABG) or valve surgery, or combined procedures with expected postoperative mechanical ventilation
Exclusion criteria
\- Patient receiving invasive mechanical ventilation prior to surgery
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Prevalence of significant airway opening pressure | up to 1 hour after intensive care admission | airway opening pressure ≥ 5 cmH₂O |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Airway opening pressure prevalence based on body mass index | up to 1 hour | Airway opening pressure prevalence base on Obesity status (body mass index ≥30 vs. \<30 kg/m²) |
| Airway opening pressure prevalence based on cardiopulmonary bypass duration | up to 1 hour | Airway opening pressure prevalence based on cardiopulmonary bypass duration (minutes) |
| Airway opening pressure prevalence based on left ventricular dysfunction | up to 1 hour | Airway opening pressure prevalence based on left ventricular dysfunction (Ieft ventricular ejection fraction \< 50 percent vs \> 50 percent) |
| Airway opening pressure prevalence based on inotropic support | up to 1 hour | Airway opening pressure prevalence based on use of amines (\< 0.1 mcg/kg/min or norepinephrine equivalent vs \> 0.1 mcg/kg/min or norepinephrine equivalent) |
| Airway opening pressure prevalence based on age | up to 1 hour | Airway opening pressure prevalence base on age |
| Airway opening pressure prevalence based on intraoperative fluid balance | up to 1 hour | Airway opening pressure prevalence base on intraoperative fluid balance |
| Patient position | up to 1 hour | Comparison of airway opening pressure values in flat versus semi-recumbent (30-degree) positions |
| Positive end expiratory pressure level | up to 1 hour | Number of times Positive end expiratory pressure is set greater than measured airway opening pressure |
| Extubation | Day7 | Correlation between airway opening pressure and time to extubation |
| Hemodynamic tolerance base on blood pressure drop | up to 15 minutes | Evaluation of hemodynamic tolerance based on arterial pressure during positive end-expiratory pressure adjustment (if inotropic agents are required, an increase of more than 0.05 mcg/kg/min in norepinephrine equivalent is considered significant) |
| Hemodynamic tolerance base on pulse oxygen saturation drop | up to 15 minutes | Evaluation of hemodynamic tolerance based on pulse oxygen saturation. A decrease in pulse oxygen saturation of 5 percent from baseline or more is considered significant. |
| Non-interruptive airway opening pressure measurement method | up to 1 hour | The novel non-interruptive airway opening pressure measurement method will be validated |
| Feasibility of airway opening pressure measurement | up to 1 hour | proportion of patients in whom the maneuver is successfully completed |
Countries
Canada
Outcome results
None listed