Potential for Inhaled Nitric Oxide and Ventilation-Perfusion Mismatch by Electrical Impedance Tomography in the ARDS Patients With Lung Recruitment

Far Eastern Memorial Hospital

Status: Invitation-only

Conditions: Acute Respiratory Distress Syndrome; Nitric Oxide

Treatments: Device: Lung recruitment; Device: Lung recruitment combined inhaled Nitric oxide

Study type: Interventional

Funder types: Other

Identifiers

NCT04776408

109200-F

Details and patient eligibility

About

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.

Full 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.

Enrollment: 100 estimated patients

Sex: All

Ages: 20 to 99 years old

Volunteers: No Healthy Volunteers

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

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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100 participants in 2 patient groups

Control group_Use Lung recruitment

Active Comparator group

Description:

Use the Lung recruitment,

Treatment:

Device: Lung recruitment

Study group_Use Lung recruitment combined inhaled Nitric oxide

Experimental group

Description:

Use the Lung recruitment combined inhaled Nitric oxide,

Treatment:

Device: Lung recruitment combined inhaled Nitric oxide