Incline Positioning in COVID-19 Patients for Improvement in Oxygen Saturation (UPSAT)

Study Design: The investigators will conduct a pilot study to examine the acute effects of inclined posture on oxyhemoglobin saturation and the feasibility of conducting randomized controlled clinical trial among patients with confirmed or suspected COVID-19-associated hypoxia.

In a subgroup of participants, the investigators will examine the acute effect of postural therapy (15-degree incline on hospital beds) on oxyhemoglobin saturation among hypoxic patients to establish a biologic response. The investigators will enroll a subset of participants (n=16) who will lie supine on hospital beds, which will be placed in the horizontal (flat) or 15-degree inclined (reverse Trendelenberg) orientation in random order. During this time, the investigators will continuous record pulse oximetry, pulse rate and variations in peripheral arterial tone with WatchPAT one devices. Subjects will be visually monitored for work of breathing during this time. If work of breathing becomes excessive, as defined as a sustain respiratory rate of >25 and an increase of >5 breaths per minute from baseline, or oxygenation decreases below 88% for > 30 seconds in the inclined position, then maneuvers will be stopped. If the patient meets these criteria in the flat position, then the investigators sit the patient upright, and allow breathing to return to baseline before examining responses in the inclined position.

The investigators will randomize participants to have beds placed in 15-degree incline or usual care (ad-lib positioning) for 72 hours. During the first night in a subgroup of participants, the investigators will record oxygenation, sleep wake state and markers of sympathetic activity with WatchPAT One devices, which can obtain cardiopulmonary parameters with high temporal resolution. The investigators will obtain vital signs from the data warehouse, which archives telemetry data with a maximum sampling frequency of 1 minute. The investigators will record adherence with continuous accelerometry sensors placed on the bed rails and on the anterolateral surface of participants' chests to measure bed and participants' positions, respectively. Aside from position, participants will receive usual treatment for COVID-19.

The investigators will enroll in 3 phases. At the end of each phase, the investigators will assess for completion of milestones for proceeding to the subsequent phase, as detailed below:

1. Pilot Study: The investigators will pilot the study in 16 participants to obtain critical information on logistics of conducting the trial including performance of recording instruments in a biocontainment environment, to examine the feasibility of the intervention, perform preliminary safety evaluations to ascertain potential harm and to determine whether the intervention results in a meaningful difference in body position.
2. Phase II RCT: If inclined therapy results in a difference in body position and no significant safety issues were detected, the investigators will conduct a phase II randomized-controlled trial (RCT) in 70 participants (see sample size calculation below) to estimate the effect size of inclined position on rates of intubation and determine sample size for a Phase III trial.

Randomization will be occur in both phases and will be stratified by study phase and study site.