Non-Invasive Ventilation Guidelines

Initiation and Adjustment of Non-Invasive Ventilation

Aim for as many hours as possible in the first 24 hours or until improvement in patients with respiratory failure, especially in those with COPD, with stability expected to be reached by 4-6 hours 1
If non-invasive ventilation (NIV) is failing, consider adjustments such as increasing EPAP, target pressure, or IPAP, and checking for mask fit and circuit leaks to improve patient synchronization with the ventilator 1
Initial NIV settings should include IPAP: 15-20 cmH2O and EPAP: 3-5 cmH2O, as recommended by the British Thoracic Society and the American College of Physicians 2, 3, 4

Consider non-invasive ventilation if respiratory rate > 25 breaths/min and SpO2 < 90% in patients with respiratory failure 5
Long-term NIV should be considered in patients who have had three or more episodes of acute hypercapnic respiratory failure in the previous year 1
NIV is indicated for hypercapnic respiratory failure, especially in patients with chronic obstructive pulmonary disease (COPD), and for high-risk patients after extubation, as recommended by the British Thoracic Society and the American College of Physicians 2, 3, 4

Consider IV vasodilators if systolic BP > 100 mmHg for relief of dyspnea in patients with heart failure 5
Consider acetazolamide in combination with loop diuretics for resistant fluid overload in heart failure 5
Consider the use of bronchodilators, systemic corticosteroids, and antibiotics if indicated for COPD exacerbation, and opioids such as morphine sulfate for persistent breathlessness, as recommended by the British Thoracic Society and other authorities 2, 6

The goal of oxygen therapy is to maintain adequate oxygenation and prevent complications, with target saturations of 94-98% for patients without a risk of hypercapnia, and 88-92% for patients with a risk of hypercapnia, as recommended by the British Thoracic Society 7, 2

The following oxygen therapy devices and initial flow rates are recommended:

Severity	Device	Initial Flow Rate	Target SpO₂
Mild hypoxemia	Nasal cannulae	1-2 L/min	94-98%
Moderate hypoxemia	Simple face mask	5-6 L/min	94-98%
COPD/hypercapnic risk	Venturi mask 24-28%	2-6 L/min	88-92%
Severe hypoxemia	Reservoir mask	15 L/min	94-98%

Escalation of oxygen therapy devices should be based on clinical scenario:

Device	Initial Flow	Escalation
Nasal Cannulas	1-2 L/min	Increase up to 6 L/min
Simple Mask	5 L/min	Increase up to 10 L/min
Venturi Mask 24%	2-3 L/min	Switch to 28% (4-6 L/min)
Reservoir Mask	15 L/min	Maintain and seek specialized help

All patients treated with NIV for acute respiratory failure should undergo spirometric testing and arterial blood gas analysis while breathing air before discharge 1
Consider referral for domiciliary NIV if NIV is still needed more than one week after the acute episode 1
Target normalization of PaCO2 with high-intensity NIV settings, and monitor arterial blood gases within 60 minutes of any change in inspired oxygen concentration 9, 10, 11
Target a PaCO2 of 35-40 mmHg (5.0-5.5 kPa) to avoid extreme hyperventilation 10, 11

Invasive mechanical ventilation (IMV) should use low tidal volume (6 mL/kg predicted body weight) and apply PEEP to prevent alveolar collapse, with a recommended minute ventilation of 2-3 times normal and 100% oxygen at maximum flow, as recommended by the Critical Care society 12, 13

Consider Extracorporeal Membrane Oxygenation (ECMO) for refractory hypoxemia if PaO2/FiO2 <100 mmHg despite optimized ventilation, early in disease course, and if patient has potentially reversible condition, as recommended by the Extracorporeal Life Support Organization 14
Positioning the patient upright can optimize respiratory mechanics, and assist with airway clearance techniques if secretions are present, as recommended by the British Thoracic Society and other authorities 15, 16

The American Heart Association recommends using BNP cutoffs for suspected heart failure, with a sensitivity of 98% and specificity of 47% at 100 pg/mL, and a sensitivity of 87% and specificity of 64% at 200 pg/mL 17
Age-adjusted NT-proBNP cutoffs can improve specificity for suspected heart failure 17
The American College of Cardiology recommends considering non-invasive ventilation for respiratory failure in patients with suspected heart failure 18