From the Guidelines
Acute hypoxemic respiratory failure should be treated with supplemental oxygen therapy, starting with a reservoir mask at 15 L/min if the initial SpO2 is below 85%, or nasal cannulae or simple face mask otherwise, with the goal of maintaining an oxygen saturation target range of 94-98%. The causes of acute hypoxemic respiratory failure can be diverse, including pulmonary infection, inflammation, or exacerbation of chronic heart or lung disease, and treatment should be tailored to address the underlying cause 1.
Treatment Options
- Supplemental oxygen therapy is the first line of treatment, with the choice of device depending on the severity of hypoxemia and the patient's risk factors for hypercapnic respiratory failure 1.
- For patients with severe hypoxemia, high-flow nasal cannula (HFNC) may be used, providing airflows of up to 50-60 L/min and reliably achieving an FiO2 of up to 100% 1.
- Non-invasive ventilation, such as CPAP or BiPAP, may be used if oxygenation remains inadequate, and endotracheal intubation and mechanical ventilation may be necessary for severe cases 1.
Addressing Underlying Causes
- Antibiotics may be used to treat pneumonia, diuretics like furosemide may be used to treat pulmonary edema, and bronchodilators such as albuterol may be used to treat bronchospasm 1.
- Prone positioning may benefit patients with severe ARDS, and hemodynamic stability, adequate sedation, and monitoring of arterial blood gases, vital signs, and ventilator parameters are crucial throughout treatment 1.
Key Considerations
- The oxygen saturation target range should be individualized based on the patient's underlying condition, with a goal of 94-98% for most patients, but 88-92% for those with coexisting COPD or other risk factors for hypercapnic respiratory failure 1.
- HFNC has been shown to have several benefits over conventional oxygen therapy, including decreased risk of patient self-inflicted lung injury, improved ventilation, and enhanced secretion clearance 1.
From the Research
Causes of Acute Hypoxemic Respiratory Failure
- The exact causes of acute hypoxemic respiratory failure are not explicitly stated in the provided studies, but it can be inferred that conditions such as COPD, cardiogenic pulmonary edema, pneumonia, and acute respiratory distress syndrome (ARDS) can lead to this condition 2, 3, 4, 5.
Treatment Options for Acute Hypoxemic Respiratory Failure
- Noninvasive ventilation and high-flow nasal cannula oxygen are alternative strategies to conventional oxygen therapy for patients with acute hypoxemic respiratory failure 2, 3.
- Mechanical ventilation with lung-protective tidal volumes and positive end-expiratory pressure (PEEP) can be used to manage acute respiratory failure 4, 5.
- Rescue therapies such as airway pressure release ventilation, continuous neuromuscular blockade, inhaled nitric oxide, and extracorporeal membrane oxygenation can be considered for refractory hypoxemia 4, 5, 6.
- Prone positioning and inhaled vasodilators may also improve oxygenation in patients with severe hypoxemic respiratory failure 4, 6.
- Fluid-restricted strategy and consideration of nonrespiratory causes of hypoxemia are also important in the management of acute hypoxemic respiratory failure 4.
Predictors of Intubation in Acute Hypoxemic Respiratory Failure
- A respiratory rate greater than or equal to 30 breaths/min is a predictor of intubation under standard oxygen therapy 2.
- A PaO2/FIO2 ratio less than or equal to 200 mm Hg and a tidal volume greater than 9 mL/kg of predicted body weight are independent predictors of intubation under noninvasive ventilation 2.
- Increased heart rate is a factor associated with intubation one hour after high-flow nasal cannula oxygen initiation 2.