Treatment of ARDS With Instilled T3

Inclusion Criteria:

Study population is critically ill patients requiring mechanical ventilatory support for ARDS in an intensive care unit.

• Adults (≥18 years of age).

• Male or female (non-pregnant).

• Clinical diagnosis of ARDS (all are required):

1. Onset: <= 7 days.

2. Chest x-ray: Bilateral Patchy Opacities, Infiltrates.

3. Mechanical Vent Support: PEEP or CPAP Support >= 5 cm H2O.

4. Pulmonary Edema: Not fully explained by cardiogenic etiology.

5. Hypoxia: PaO2/FIO2 Ratio <300, or O2Sat/FIO2 Ratio <315.

• On mechanical ventilatory support.

• Capable of giving informed consent directly or from the subject's legally authorizedrepresentative (LAR) as determined by the site Principal Investigator and/or Sub-Investigators.

Exclusion Criteria:

Patients with any of the following conditions will be excluded from this trial:

• Inadequate medical history for determining inclusion/exclusion criteria, asdetermined by the Principal Investigator and/or Sub- Investigators.

• Unlikely to complete the protocol with clinic follow-up after discharge, asdetermined by the Principal Investigator and/or Sub- Investigators or hospicestatus.

• Prior history of thyroid cancer or hyperthyroidism, per thorough patient/familyinterviews, review of past medical history, medication list, laboratory test.

• Prior history of cardiovascular disease defined as:

1. Hypertensive crisis in the past 3 months (systolic >200, or diastolic >120mmHg),

2. Sustained ventricular arrhythmia in the past 3 months (duration >30 seconds)

3. Coronary artery disease (documented >=70% occlusion untreated in any coronaryvessel), as per the 2021 ACC/AHA/SCAI Guidelines for Coronary ArteryRevascularization.

4. Cardiac-related angina pectoris (>=2 episodes in the past 3 months)

5. Myocardial infarction with ischemia on ECG (i.e.,new ST- elevation/depressionof >1mm in contiguous leads).

6. Peripheral vascular disease (documented >=70% occlusion untreated in anyperipheral vessel), as per the 2018 ACC/AHA/SCAI/SIR/SVM Guidelines forAppropriate Use Criteria for Peripheral Artery Intervention.

7. Decompensated or symptomatic heart failure (i.e., hospitalized for CHFexacerbation, or a change in CHF medications within two weeks prior)

• Currently pregnant or breastfeeding.

• Known allergy to study drug.