STIMIT Activator 1 IDE Study

Inclusion Criteria:

1. Are 21 years or older, and,

2. Have recently been placed on invasive MV (enroll and randomized as soon as possibleafter intubation), and have received no more than 7 days of MV

3. Are predicted to remain on mechanical ventilation for an additional 48 hours orlonger post randomization

Exclusion Criteria:

1. Patients that are actively treated with continuous infusion of neuromuscularblocking agents beyond the enrollment period.

2. Medical condition known to affect the phrenic nerve or respiratory muscles (examplesof possible medical conditions that could affect the phrenic nerve provided in Annex 1 below).

3. Any patients with ICP probe.

4. Patients with metallic device implants or body penetrating metallic devices in theupper body area within 30cm (12inches) from the coils; known anatomy or devices inthe neck area (e.g., ECMO cannulas in the neck area, collars or cranial appliances)that would interfere with headset placement or stimulation.

5. Any non-removable electrical / electronic device (device internal or external) thatmay be prone to interaction with, or interference from the STIMIT Activator, such aspacemakers, implantable defibrillators, implanted medication pumps, bio-stimulators,deep brain stimulators, implanted nerve stimulator, deep brain stimulators orcochlear device implants.

6. BMI >40.

7. Cardiogenic or septic shock with ongoing severe hemodynamic instability that cannotbe stabilized within the enrollment period.

8. Physician thinks that the patient will not tolerate initial installation of theSTIMIT respiratory sensor.

9. Anticipating withdrawal of life support and/or shift to palliation as the goal ofcare.

10. Known to be pregnant.

11. Participating in another clinical trial studying an experimental Intervention thatcould affect the study primary outcome.

12. Patients whose ultrasonographic assessment of right-sided diaphragmatic thicknesswould be too difficult (e.g. local subcutaneous emphysema surrounding the zone ofapposition, large dressings in the zone of apposition that cannot be removed).

13. Patients with neck condition that would not allow placing the coils on the neck (e.g. open wounds that cannot be covered, skin at risk for burns).

14. Patients with significant spontaneous efforts (P0.1 < - 2) that would not be at riskfor diaphragmatic atrophy/ dysfunction.