Indications for Non-Invasive Ventilation (NIV)

Primary Indications for NIV

The British Thoracic Society recommends NIV in patients with acute exacerbation of COPD who develop respiratory acidosis, as this reduces mortality, need for intubation, and treatment failure 1, 2
NIV is indicated in acute or acute-on-chronic hypercapnic respiratory failure due to chest wall deformity or neuromuscular disease, according to the British Thoracic Society 1, 2
Continuous positive airway pressure (CPAP) should be used in patients with cardiogenic pulmonary edema who remain hypoxic despite maximal medical treatment, with NIV reserved for patients in whom CPAP is unsuccessful, as recommended by the British Thoracic Society 2
NIV (bi-level pressure support) should be used for patients with decompensated obstructive sleep apnea if respiratory acidosis is present, according to the British Thoracic Society 1, 2
The British Thoracic Society recommends NIV for weaning patients from invasive ventilation when conventional weaning strategies fail 1, 2

A trial of NIV may be undertaken in patients with respiratory acidosis secondary to acute exacerbation of bronchiectasis, though excessive secretions may limit effectiveness, as noted by the British Thoracic Society 1, 2
NIV can be used as an alternative to tracheal intubation in patients with diffuse pneumonia who become hypercapnic after remaining hypoxic despite maximum medical treatment, according to the British Thoracic Society 1, 3

The British Thoracic Society recommends that NIV should not be used in patients after recent facial or upper airway surgery, with facial abnormalities, fixed upper airway obstruction, or if vomiting 2, 5
Other contraindications include recent upper gastrointestinal surgery, inability to protect the airway, copious respiratory secretions, life-threatening hypoxemia, severe comorbidity, confusion/agitation, or bowel obstruction, as stated by the British Thoracic Society 2, 5
NIV should not be used routinely in acute asthma, according to the British Thoracic Society 1, 2

Patients with more severe acidosis should be managed in a higher dependency area, such as HDU or ICU, as recommended by the British Thoracic Society 2, 5
Arterial blood gas analysis should be measured in most patients after 1-2 hours of NIV and after 4-6 hours if the earlier sample showed little improvement, according to the British Thoracic Society 2, 5
If there is no improvement in respiratory function after 4-6 hours despite optimal ventilator settings, NIV should be discontinued and invasive ventilation considered, as noted by the British Thoracic Society 5, 6

A decision about tracheal intubation should be made before commencing NIV in every patient and documented in the case notes, as recommended by the British Thoracic Society 2
Patients with conditions where the role of NIV is not yet clearly established should only receive NIV in an HDU or ICU where facilities for immediate tracheal intubation are available, according to the British Thoracic Society 2, 3
In chest wall trauma, CPAP should be used for patients who remain hypoxic despite adequate regional anesthesia and high-flow oxygen, with monitoring in the ICU due to pneumothorax risk, as stated by the British Thoracic Society 1, 3