Interleukin-6 Guided Treatment With Dexamethasone or Tocilizumab in Patients Hospitalized With Acute Respiratory Symptoms - a Feasibility Study

Acute hypoxemic respiratory failure (AHRF) happens when the lungs are unable to absorb enough oxygen. The bloodstream is deprived of oxygen which can eventually lead to more severe conditions like multi-organ failure (MOF) and death. AHRF accounts for over 30% of patients to critical care units, thus novel treatments are sorely needed. Research has shown that blood levels of the inflammatory biomarker Interleukin-6 (IL-6) may be a reliable marker for predicting which patients with AHRF will progress into requiring intensive care unit (ICU) admission, MOF, and eventually death. IL-6 levels were shown to reliably peak several days before MOF, ICU admission, and death. Thus, the investigators believe that by identifying patients before the peak of their IL-6 levels, they will be able to administer early treatment to prevent the patient's condition from worsening. The aim of this study is to test the feasibility of a treatment strategy for AHRF based on IL-6 measurement in patients who are admitted to hospital care with AHRF. This study has two phases: 1) observational and 2) interventional. In the observational phase 1, patients who meet the inclusion and a general exclusion criteria are eligible for participation. In the observational phase, patients will have their plasma IL-6 levels measured over 2 days. Patients' clinical condition will be observed till discharge or up to 28 days of admission, and data will be collected from their medical charts. Patients participating in the observational phase 1 will be considered eligible to join the interventional phase 2 if: they are found to have elevated IL-6 levels, and they meet additional randomization exclusion criteria. In the interventional phase, patients will be randomized into 1 of 3 treatment groups: standard of care only, standard of care plus a single IV infusion of Tocilizumab, or standard of care plus treatment with oral Dexamethasone for 10 days. Patients' clinical condition will be observed till discharge or up to 28 days of admission, and data will be collected from their medical charts. A follow-up phone interview will be conducted 6 months of the end of the observation period. Patients participating in the observational phase 1 who are not eligible to participate in the interventional phase 2 will continue in the observational phase 1 only. These patients will not be randomized to a group, receive any study medications, or be contacted for the 6-month follow-up.

Inclusion Criteria 1. Age ≥18 years 2. Presence of new onset of respiratory symptoms in the previous 14 days upon presentation at the emergency department. Respiratory symptoms are characterized by at least one of the following: cough, dyspnea, or requirement of oxygen supplementation 3. Requirement of inpatient hospital management Exclusion Criteria General Exclusion: 1. Inability to provide informed consent 2. Immediate need for admission to ICU 3. Immediate need for intubation 4. Imminent death 5. Clinical team refusal Randomization Exclusion 1. Patients with known contraindications to dexamethasone or tocilizumab, or any of their components 2. Allergic reaction to tocilizumab or other monoclonal antibodies 3. Patients who are using azathioprine or cyclophosphamide 4. Active tuberculosis infection 5. ALT or AST \>10x upper limit of normal 6. Neutrophil count \