The goal of this clinical trial is to explore the effect of NO treatment on diaphragm function after mechanical ventilation with ECMO assistance. We expect to enroll a total of 80 patients who will receive mechanical ventilation and mechanical ventilation combined with ECMO treatment. Depending on the indication, they will be given NO treatment or not. In ECMO assisted mechanical ventilation + NO treatment group, the subjects will be randomly assigned to NO treatment via ventilator or membrane oxygenator. The main questions it aims to answer are:

1. Observing the influences and potential therapeutic effects of different NO insertion methods through ventilator or membrane oxygenator on the occurrence and development of ventilator-induced diaphragm (VIDD) dysfunction during ECMO assisted mechanical ventilation.
2. Exploring the potential key molecular mechanisms of NO treatment on the occurrence and development of VIDD after ECMO assisted mechanical ventilation.

Inclusion Criteria:

1. Age ≥ 18 years;
2. Tracheal intubation in our emergency department;
3. Expected survival time ≥ 72 hours;
4. Family members agree to participate and sign the informed consent form.

Exclusion Criteria:

1. Pregnant women;
2. Patients with diaphragmatic hernia or other known diaphragmatic diseases and injuries;
3. Patients with mechanical ventilation treatment within 3 months;
4. Thoracic or abdominal tumor invading the diaphragm;
5. A large amount of ascites raises the diaphragm position;
6. Upper respiratory tract malformation;
7. Trauma leading to chest collapse, etc.

Patients of mechanical ventilation with or without ECMO assistance in emergency ward