Pragmatic Trial Exploring Impact of Patient Positioning in the Management of Patients Infected With COVID-19: Supine vs. Prone

Disease Progression and Timing of Intervention The intervention described herein focuses on adjustment of patient positioning aimed at improving gas exchange and lung function in patients harboring COVID-19. This intervention will target the inpatient setting generally.

Scientific/Clinical Rationale for Approach Since emergence of the novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) now designated coronavirus disease 2019 (COVID-19), one in six affected patients becomes seriously ill. The lung appears to be the most susceptible target organ, with a large swath of symptomatic patients struggling with mild upper respiratory tract illness and severe viral pneumonia resulting in respiratory failure. This respiratory failure is often fatal, with one study showing 28% non-survivors having experienced respiratory failure. Moreover, 81-97% of patients requiring mechanical ventilation do not survive.

Like its interaction with Severe Acute Respiratory Syndrome (SARS-CoV), angiotensin converting enzyme 2 (ACE2) is the functional receptor for COVID-19. Viral adherence to host-cell membrane associated ACE2 facilitates the proximity required for viral "spike" mediated genetic material injection. In COVID-19, this spike is 10-20 times more likely to bind ACE2 than SARS. ACE2 is expressed in 0.64% of all human lung cells, with 83% of those cells being alveolar epithelial type II. In addition, gene ontology enrichment analysis showed that the ACE2-expressing alveolar epithelial type II have high levels of multiple viral process-related genes, including regulatory genes for viral processes, viral life cycle, viral assembly, and viral genome replication, suggesting that the ACE2-expressing alveolar epithelial type II cells facilitate coronaviral replication in the lung. Thus, these cells likely serve as a ready reservoir for viral invasion. Perhaps more importantly, alveolar type II cells function to generate and recycle surfactant essential to respiratory activity. Surfactant defends against alveolar collapse at low lung volume and protects the lung from injuries/infections caused by inhaled particles and micro-organisms. In COVID-19, if these vital cells are being destroyed, alveolar failure may ensue with severe lung impairment. Thus, interventions that are aimed at improving pressure normalization and alveolar protection may be beneficial in these patients.

Prone positioning (PP) has long been used to combat hypoxemia in acute respiratory distress syndrome (ARDS). Improvements in gas exchange result from improved alveolar ventilation and blood flow redistribution with enhanced perfusion following. PP reduces lung over inflation and bolsters alveolar recruitment. PP also promotes uniformity of vertical pleural pressure gradients resulting in more uniform alveolar size. Considering these physiologic factors together, the investigators hypothesize PP serves to balance stress and strain within the lungs of non-critically ill patients with COVID-19 leading to improved outcomes compared to traditional supine positioning.

Prior Research Supporting the Positioning Model: