Acute Respiratory Distress Syndrome, Nitric Oxide
Conditions
Keywords
Electrical Impedance Tomography, Acute Respiratory Distress Syndrome, Inhaled Nitric Oxide, Ventilation-Perfusion mismatch, Lung recruitment
Brief summary
In the recent years, the treatment of Acute Respiratory Distress Syndrome has been proved that lung recruitment re-opens the non-ventilated alveolar to improve ventilation, and inhaled Nitric Oxide dilates non-perfused pulmonary vascular to improve perfusion. Both of these could improve ventilation-perfusion mismatch to enhance oxygenation. However, Ventilation-Perfusion mismatch is devided into ventilated nonperfused lung units(dead space) or perfused nonventilated units(shunt). No published study has evaluated the availability of lung recruitment combined with inhaled Nitric oxide in patients with ARDS. The aims of our study are to measure dead space or shunt fraction before and after inhaled Nitric Oxide in moderate to severe Acute Respiratory Distress Syndrome patients indicated Nitric oxide in FEMH MICU on 2021/01-2022/12, injected a bolus of 10mL of 3% NaCl solution via the central venous catheter with two-step recruitment maneuver by Electrical Impedance Tomography, which monitors ventilation-perfusion mismatch to evaluate whether the patient has potential to improve V/Q mismatch by Nitric oxide.
Detailed description
Normally, pulmonary arteries in areas of alveolar hypoxia will constrict as a physiologic response to preserve ventilation/perfusion (V¬/Q¬) matching. However, in ARDS, this normal vasoconstrictive response is impaired. Because the body is unable to shunt blood away from the diseased alveoli, these nonaerated alveoli receive excessive blood flow, which contributes to severe V¬/Q¬ mismatching and an intrapulmonary right-to-left shunting of blood flow, which causes hypoxemia. In the recent years, the treatment of Acute Respiratory Distress Syndrome has been proved that lung recruitment re-opens the non-ventilated alveolar to improve ventilation, and inhaled Nitric Oxide dilates non-perfused pulmonary vascular to improve perfusion. Both of these could improve ventilation-perfusion mismatch to enhance oxygenation. However, Ventilation-Perfusion mismatch is devided into ventilated nonperfused lung units(dead space) or perfused nonventilated units(shunt). No published study has evaluated the availability of lung recruitment combined with inhaled Nitric oxide in patients with ARDS. The aims of our study are to measure dead space or shunt fraction before and after inhaled Nitric Oxide in moderate to severe Acute Respiratory Distress Syndrome patients indicated Nitric oxide in FEMH MICU on 2021/01-2022/12, injected a bolus of 10mL of 3% NaCl solution via the central venous catheter with two-step recruitment maneuver by Electrical Impedance Tomography, which monitors ventilation-perfusion mismatch to evaluate whether the patient has potential to improve V/Q mismatch by Nitric oxide.
Interventions
Ventilator combined inhaled Nitric oxide and Electrical Impedance Tomography monitor the V/Q mismatch
Ventilator and Electrical Impedance Tomography monitor the V/Q mismatch
Sponsors
Study design
Masking description
During this period, all patients were total sedation using continuous infusion, to prevent any spontaneous breathing .All patients were ventilated using a ventilator
Intervention model description
Moderate to severe ARDS patient on mechanical ventilation in Far Eastern Memorial Hospital MICU
Eligibility
Inclusion criteria
* Moderate to severe ARDS patient on mechanical ventilation in MICU. (P/F≦ 200 with PEEP ≥ 5cmH20) (PEEP greater than or equal to 5 cm H2O and Berlin criteria for ARDS)
Exclusion criteria
* Hemodynamic instability or severe COPD, pulmonary embolism * Acute brain injury, seizure attack, AMI, AIDS, severe arrhythmia * On pacemaker * Pregnant * Thoracic trauma or burn injury * Pneumothorax
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| V/Q mismatch | 15 minutes | Compare the V/Q mismatch between two groups |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| PaO2/FiO2 ratio improvement rate | 15 minutes | Oxygention improve rate |
Countries
Taiwan