EIT Evaluation of the Impact of Inhaled Nitric Oxide on Ventilation/Perfusion Mismatch in ARDS Patients Receiving Noninvasive Respiratory Support

EIT Evaluation of the Impact of Inhaled Nitric Oxide on Ventilation/Perfusion Mismatch in ARDS Patients Receiving Noninvasive Respiratory Support: A Prospective Physiological Study

This study aimed to quantitatively evaluate the immediate effect of inhaled nitric oxide on the ventilation / perfusion ratio in ARDS patients receiving nasal high flow oxygen therapy or noninvasive ventilation using electrical impedance tomography.

Study Overview

• Status: Not yet recruiting
• Conditions: ARDS (Acute Respiratory Distress Syndrome)
• Intervention / Treatment: Device: Inhale different doses of nitric oxide

Detailed Description

The immediate effect of different doses of iNO (5-40 ppm) on the degree of v/q mismatch in the lungs of ARDS patients receiving hfnc or NIV was quantitatively evaluated by EIT. Objective to explore the effects of different doses of iNO on oxygenation, ventilation distribution and perfusion distribution in ARDS patients using hfnc or NIV, as well as the differences and influencing factors of individual response.

• Study Type: Observational
• Enrollment (Estimated): 40

Contacts and Locations

• Study Contact: Name: Dang Xinya Dang Xinya, bachelor; Phone Number: +86 158 2199 3005; Email: dang.xinya@zs-hospital.sh.cn
• Study Contact Backup: Name: Liu Kai Liu Kai, bachelor; Phone Number: +86 135 1213 6346; Email: Liu.kai1@zs-hospital.sh.cn

Study Locations

• China
  • Shanghai, China, 200000
    • Nitric Oxide Therapy Device
    • Contact: Nanjing Nuoling Biotechnology Co., Ltd Nuoling Nanjing Nuoling; Phone Number: 025-58222737-8001; Email: contact@novlead.com
    • Principal Investigator: Liu Kai Kai Liu, bachelor
    • Sub-Investigator: Dang Xinya Xinya Dang, bachelor

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Non invasive ventilation (NIV) with PEEP or CPAP ≥ 5 cmH2O or nasal high flow oxygen therapy (hfnc) with flow rate ≥ 30 l/min met the diagnostic criteria of non intubated ARDS according to the new global definition of ARDS: pao2/fio2 ≤ 300MMHG or spo2/fio2 ≤ 315 (SpO2 ≤ 97%);

Description

Inclusion Criteria:

1. Age ≥ 18 years, gender unlimited;
2. Non invasive ventilation (NIV) with PEEP or CPAP ≥ 5 cmH2O or nasal high flow oxygen therapy (hfnc) with flow rate ≥ 30 l/min met the diagnostic criteria of non intubated ARDS according to the new global definition of ARDS: pao2/fio2 ≤ 300MMHG or spo2/fio2 ≤ 315 (SpO2 ≤ 97%);
3. Patients with spontaneous breathing and clear consciousness can cooperate with instructions and hold breath for ≥ 8s;
4. Patients with spontaneous breathing and clear consciousness can cooperate with instructions and hold breath for ≥ 8s;

Exclusion Criteria:

1. There are signs of worsening respiratory failure requiring immediate intubation: respiratory rate > 40 times / min with severe use of auxiliary respiratory muscles or contradictory breathing, or Paco ₂ > 50 mmHg and pH < 7.25;
2. Hemodynamic instability or the presence of refractory shock; That is, the vasoactive drugs increased by more than 30% within 6 hours, or the norepinephrine dose exceeded 0.5 μ g /kg/min;
3. There are contraindications to EIT monitoring, such as thoracic implantable defibrillator / pacemaker, large area of severe skin damage on the chest, serious allergy to electrode patches, etc;
4. There are contraindications to the use of iNO: such as severe left ventricular dysfunction, active bleeding, etc;
5. Patients with intracranial hypertension, severe arrhythmia or digestive tract obstruction;
6. Pneumothorax and massive pleural effusion were not treated;
7. Chronic kidney disease;
8. Pregnant or lactating women;
9. Participating in other studies;
10. The investigator judged that there were any other circumstances not suitable for participation in this study. -

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Using transnasal high flow; ARDS patients using high nasal flow	Device: Inhale different doses of nitric oxide; T0 (baseline): 20 to 30 minutes after initial stabilization; T1 (iNO 5ppm 1h): The patient non invasively inhales 5ppm NO for 1h. If the reaction standard (PaO2/FiO2 improvement ≥ 20%) is met, maintain the dose until the end of the study. Otherwise, continue to double the NO concentration and proceed with the following steps:; T2 (iNO 10ppm 1h): The patient non invasively inhales 10ppm of NO for 1h. If the reaction standard is met, maintain the dose until the end of the study, otherwise continue to double the NO concentration and proceed with the following steps; T3 (iNO 20ppm 1h): The patient non invasively inhales 20ppm NO for 1h. If the reaction standard is met, maintain the dose until the end of the study, otherwise continue to double the NO concentration and proceed with the following steps; T4 (iNO 40ppm 1h): The patient non invasively inhales 40ppm NO for 1h. All subjects completed the evaluation regardless of whether they met the response criteria.
Use a non-invasive mask; ARDS patients using non-invasive face masks	Device: Inhale different doses of nitric oxide; T0 (baseline): 20 to 30 minutes after initial stabilization; T1 (iNO 5ppm 1h): The patient non invasively inhales 5ppm NO for 1h. If the reaction standard (PaO2/FiO2 improvement ≥ 20%) is met, maintain the dose until the end of the study. Otherwise, continue to double the NO concentration and proceed with the following steps:; T2 (iNO 10ppm 1h): The patient non invasively inhales 10ppm of NO for 1h. If the reaction standard is met, maintain the dose until the end of the study, otherwise continue to double the NO concentration and proceed with the following steps; T3 (iNO 20ppm 1h): The patient non invasively inhales 20ppm NO for 1h. If the reaction standard is met, maintain the dose until the end of the study, otherwise continue to double the NO concentration and proceed with the following steps; T4 (iNO 40ppm 1h): The patient non invasively inhales 40ppm NO for 1h. All subjects completed the evaluation regardless of whether they met the response criteria.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Oxygenation index	Blood gas analyzer was used for analysis after arterial extraction	baseline, before intervention; Time point 1: After inhaling 5ppm of NO for 1 hour; Time point 2: After inhaling 10ppm of NO for 1 hour; Time point 3: After inhaling 20ppm of NO for 1 hour; Time point 4: After inhaling 40ppm of NO for 1 hour
Ventilation/perfusion ratio	Electrical impedance tomography	baseline, before intervention; After inhaling 5ppm of NO for 1 hour; After inhaling 40ppm of NO for 1 hour

Collaborators and Investigators

• Sponsor: Ming Zhong
• Investigators: Principal Investigator: Liu Kai Liu Kai, bachelor, Fudan University; Study Chair: Dang Xinya Xinya Dang, bachelor, Fudan University; Study Director: Zhong Ming Ming Zhong, doctor, Fudan University

Study record dates

Study Major Dates

• Study Start (Estimated): June 30, 2026
• Primary Completion (Estimated): December 30, 2027
• Study Completion (Estimated): December 31, 2027

Study Registration Dates

• First Submitted: May 7, 2026
• First Submitted That Met QC Criteria: May 24, 2026
• First Posted (Actual): June 1, 2026

Study Record Updates

• Last Update Posted (Actual): June 1, 2026
• Last Update Submitted That Met QC Criteria: May 24, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: ARDS; inhaled nitric oxide
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Lung Diseases; Lung Injury; Acute Lung Injury
• Other Study ID Numbers: B2026-187

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: All IPDs collected during the trial period
• IPD Sharing Time Frame: 2027/6/30-2028/12/30
• IPD Sharing Access Criteria: publish a paper
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: Yes
• product manufactured in and exported from the U.S.: No