Adult Respiratory Failure Intervention Study Africa (ARISE-AFRICA)

A Multicentre, Randomized, Clinical Trial of Respiratory Support With Standard Low Flow Oxygen Therapy, Continuous Positive Airway Pressure, and High-flow Oxygen Therapy in Adults With Acute Hypoxemic Respiratory Failure in Uganda

The dearth of Intensive care units in low resource settings portends for poor outcomes amongst patients with acute hypoxemic respiratory failure (AHRF) . To our knowledge, the effect of CPAP and HFNC on major outcomes has not been assessed in adults with AHRF in resource-limited settings. The aim of this prospective, multicenter, randomized, controlled, trial is to determine whether High-flow oxygen through a nasal cannula (HFNC) or Continuous positive airway pressure (CPAP) system can reduce mortality among patients with acute hypoxemic respiratory failure (AHRF) in a limited resource setting as compared with standard low flow oxygen therapy?

The care for the critically ill patient typically takes place in the intensive care unit (ICU). ICU care is quite expensive, even in resource rich countries. The most common reason for ICU admission globally is respiratory support for acute hypoxemic respiratory failure (AHRF). In patients with AHRF, the need for invasive mechanical ventilation is associated with high mortality, especially in low income countries (LICs), given the scarce availability of invasive mechanical ventilation. Some studies suggest that administration of ventilatory support through a mask may be effective in resource-limited settings. However, there is no clinical study data in adults to support this evidence. Human and material constraints are major barriers for the care of critically-ill patients in resource limited settings , advocating the need for a frugal approach. Furthermore, the scarcity of intensive care unit care in LICs contributes to a high mortality among acutely ill patients. The current corona virus pandemic has further highlighted the need for frugal acute care interventions in LICs. Continuous positive airway pressure (CPAP) is a simple to use and affordable technique for noninvasive ventilatory support. High-flow oxygen through a nasal cannula (HFNC) may also offer an alternative in patients with hypoxemia. The high flow rates may also decrease physiological dead space by flushing expired carbon dioxide from the upper airway, a process that potentially explains the observed decrease in the work of breathing. Frugal CPAP or HFNC , as compared with standard oxygen therapy, could reduce the mortality among adults presenting with AHRF in a resource-limited setting.

In the high-flow-nasal cannula group, oxygen will be delivered through a heated humidifier and applied continuously through large-bore bi-nasal prongs, with a gas flow rate of 40-60 liters per minute and adjusted based on the clinical response.

Patients assigned to the CPAP plus oxygen group will receive periods of CPAP in addition to the standard treatment. CPAP will be started at 7.5 cm of water. The level will be decreased to 5 cm of water or increased to 10 cm of water as needed based on the clinical response and tolerance.

Patients assigned to the standard treatment group will receive oxygen delivered through a Non-rebreather face mask until endotracheal intubation, death, or fulfillment of oxygen delivery cessation criteria (an oxygen saturation by pulse oximetry (SpO2) above 92% without oxygen and a respiratory rate below 25 cycles/min).

Inclusion Criteria: De novo acute respiratory distress, as defined by dyspnea, use of accessory respiratory muscles, and a respiratory rate of 25 breaths per minute or more, Hypoxemia, as defined by a ratio of the partial pressure of arterial oxygen (PaO2) to the fraction of inspired oxygen (FiO2) of less than 300 mm Hg or a oxygen saturation by pulse oximetry SpO2/FiO2 ratio <315 will be considered for inclusion Informed consent obtained in accordance with local regulations; Exclusion Criteria: Exacerbation of asthma, chronic obstructive pulmonary disease or another known or suspected chronic respiratory disease; Absolute contraindications to CPAP or HFNC Cardiac arrest; severe ventricular arrhythmia; shock defined by the need for vasopressors (dopamine > 5 microg/kg/min or adrenaline or noradrenaline at any dose) Altered consciousness (Coma Glasgow Score below 12 points); Do not intubate order, do not resuscitate order, or decision to limit full care taken before obtaining informed consent; Refusal to participate, prior enrolment in the trial, participation in another interventional study on respiratory distress;