The number of COVID-19 cases has been growing exponentially, so that the industrialized economies are facing a significant shortage in the number of ventilators available to meet the demands imposed by the disease. Noninvasive ventilatory support can be valuable for certain patients, avoiding tracheal intubation and its complications. However, non-invasive techniques have a high potential to generate aerosols during their implementation, especially when masks are used in which it is virtually impossible to completely prevent air leakage and the dispersion of aerosols with viral particles. In this context, a helmet-like interface system with complete sealing and respiratory isolation of the patient's head can allow the application of ventilatory support without intubation and with safety and comfort for healthcare professionals and patients. This type of device is not accessible in Brazil, nor is it available for immediate import, requiring the development of a national product. Meanwhile, a task force under the coordination of the School of Public Health (ESP) and Fundação Cearense de Apoio à Pesquisa (FUNCAP), with support from SENAI / FIEC and the Federal Universities of Ceará (UFC) and the University of Fortaleza (UNIFOR) advanced in the development of a prototype and accessory system capable of providing airway pressurization through a helmet-type interface, which was called the Elmo System.

Objectives: 1. Validate the functionalities to fulfill the requirements and evaluate the usability of the Elmo System and 2. Evaluate the effectiveness of the Elmo system in the treatment of support to patients with hypoxemic respiratory failure caused by COVID-19.

Methods: This is a study divided into two stages. For objective 1, tests will be carried out on healthy volunteers using prototypes of the Elmo system and assessing whether their effectiveness in providing positive airway pressure and their usability from the perspective of their primary users (doctor, physiotherapist and nurses) and the comfort of the volunteer. After the tests to meet the requirements: continuous positive airway pressure (CPAP) offer, guarantee of the maintenance of alveolar ventilation without carbon dioxide (CO2) rebreathing, monitoring of intra-ELMO pressure, minimization of the adverse effects of the system such as noise, face temperature, dryness of the airways and overall comfort . In addition, realistic simulations will be carried out, centered on the assessment based on heuristic principles by a multiprofessional team with experience in mechanical ventilation, to assess the performance of the new equipment in the execution of the pre-defined skills. The second phase will consist of a clinical trial with application of the Elmo System to 10 patients with hypoxemic respiratory failure by COVID-19, to evaluate its effectiveness, through the analysis of physiological variables and patient comfort, as well as their clinical outcomes (need for tracheal intubation) and Insuf recovery time. Resp. Hypoxemic and need for O2 in a referral hospital for the treatment of this condition in Fortaleza / Ceara.

Inclusion Criteria:

• Adult patient, age> or = 18 years, both sexes;
• Patient should be alert, oriented, and cooperative;
• When using oxygen therapy by CNO2> or = 4L/min, MR> or = 8 L/min of O2 or MV 50%, for maintain SpO2> 92%;
• Gasometric parameters (pre ELMO, up to 30 min before): pH> 7.35, PaO2> 60 mmHg;
• RX or chest CT scan with bilateral parenchymal opacities from the last 24 hours.

Exclusion Criteria:

• Exacerbation of Asthma, Chronic Obstructive Pulmonary Disease (COPD), pulmonary fibrosis or other lung diseases;
• Hemodynamic instability (SBP <90 mmHg or MBP <65 mmHg or need for vasoactive drugs);
• Pneumothorax or pneumomediastinum;
• Respiratory acidosis (pH <7.35 with PaCO2 >46mmHg);
• Signs of respiratory muscle fatigue (paradoxical breathing, accessory muscle use);
• Nausea or vomiting;
• Disorders of the auditory canal;
• Use of nasoenteric or nasogastric feeding tubes;
• Imminent risk of respiratory arrest.