Clinical trial NCT04776408: Potential for Inhaled Nitric Oxide and Ventilation-Perfusion Mismatch by Electrical Impedance Tomography in the ARDS Patients With Lung Recruitment
Official title: Potential for Inhaled Nitric Oxide and Ventilation-Perfusion Mismatch by Electrical Impedance Tomography in the Acute Respiratory Distress Syndrome Patients With Lung Recruitment
Study type: INTERVENTIONAL
Overall status: UNKNOWN
Phase: NA
Conditions: Nitric Oxide
Acute Respiratory Distress Syndrome
Keywords: Electrical Impedance Tomography
Acute Respiratory Distress Syndrome
Inhaled Nitric Oxide
Ventilation-Perfusion mismatch
Lung recruitment
Lead sponsor: Far Eastern Memorial Hospital
Sponsor class: OTHER
First posted: 2021-03-01
Enrollment: 100
Sex: ALL
Minimum age (years): 20
Maximum age (years): 99
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Allocation: RANDOMIZED
Intervention model: PARALLEL
Intervention model description: Moderate to severe ARDS patient on mechanical ventilation in Far Eastern Memorial Hospital MICU
Primary purpose: TREATMENT

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.

Eligibility criteria: 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

Primary outcomes:
measure: V/Q mismatch
timeFrame: 15 minutes
Secondary outcomes:
measure: PaO2/FiO2 ratio improvement rate
timeFrame: 15 minutes
Other outcomes:
Locations:
city: Taipei county
country: Taiwan
facility: Far Eastern Memorial Hospital
state: Banqiao Dist
Study officials:
affiliation: Far Eastern Memorial Hospital
name: Hou T Chang, Doctor
role: STUDY_DIRECTOR
affiliation: Far Eastern Memorial Hospital
name: Ping H Wang, Bachelor
role: STUDY_DIRECTOR
affiliation: Far Eastern Memorial Hospital
name: Mei Y Chang, Master
role: STUDY_DIRECTOR
References:
citation: Bluth T, Kiss T, Kircher M, Braune A, Bozsak C, Huhle R, Scharffenberg M, Herzog M, Roegner J, Herzog P, Vivona L, Millone M, Dossel O, Andreeff M, Koch T, Kotzerke J, Stender B, Gama de Abreu M. Measurement of relative lung perfusion with electrical impedance and positron emission tomography: an experimental comparative study in pigs. Br J Anaesth. 2019 Aug;123(2):246-254. doi: 10.1016/j.bja.2019.04.056. Epub 2019 May 31.
citation: Mauri T, Spinelli E, Scotti E, Colussi G, Basile MC, Crotti S, Tubiolo D, Tagliabue P, Zanella A, Grasselli G, Pesenti A. Potential for Lung Recruitment and Ventilation-Perfusion Mismatch in Patients With the Acute Respiratory Distress Syndrome From Coronavirus Disease 2019. Crit Care Med. 2020 Aug;48(8):1129-1134. doi: 10.1097/CCM.0000000000004386.