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.
Age ≥ 18 years, gender unlimited;
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%);
Patients with spontaneous breathing and clear consciousness can cooperate with instructions and hold breath for ≥ 8s;
Patients with spontaneous breathing and clear consciousness can cooperate with instructions and hold breath for ≥ 8s;
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;
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;
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;
There are contraindications to the use of iNO: such as severe left ventricular dysfunction, active bleeding, etc;
Ming Zhong
Lead sponsor
Shanghai Zhongshan Hospital
Sponsor institution