Key points Non-invasive Ventilation

Indications

Bedside observations

• Increased dyspnoea—moderate to severe
• Tachypnoea
• Signs of increased work of breathing, accessory muscle use, and abdominal paradox

Gas exchange

• Acute or acute on chronic ventilatory failure (best indication), >6.0 kPa, pH<7.35
• Hypoxaemia

Contraindications
Absolute

• Respiratory arrest
• Unable to fit mask

Relative

• Medically unstable—hypotensive shock
• Uncontrolled cardiac ischaemia or arrhythmia
• Uncontrolled copious upper gastrointestinal bleeding
• Agitated, uncooperative
• Unable to protect airway
• Swallowing impairment
• Excessive secretions not managed by secretion clearance techniques
• Multiple (i. two or more) organ failure
• Recent upper airway or upper gastrointestinal surgery 

– The strongest evidence for use of non-invasive ventilation (NIV) is in patients with respiratory failure secondary to either chronic obstructive pulmonary disease or cardiogenic pulmonary oedema

– NIV is emerging as an alternative to MV in a number of different clinical situations.

– When NIV is commenced outside critical care, a defined plan should already be in place if NIV is unsuccessful.

– NIV should not delay intubation and MV in those patients who fail to respond to or deteriorate on NIV.

– Type Il respiratory failure, COPD, It is now considered the first-line therapy in COPD but patients with severe academia (pH<7.25) and hypercarbic coma considered as contraindications to NIV.

– Some small RCTs suggest that using NPPV in acute exacerbations of asthma may improve respiratory parameters and reduce intubation rates.

– NIV Indicated in morbid obesity, associated with certain respiratory syndromes such as obstructive sleep apnoea and chronic alveolar hypoventilation.

– The use of NIV has been demonstrated to improve quality of life and survival in patients with advanced neuromuscular disorders

– There is good evidence to support the use of NIV in acute pulmonary oedema. Theoretical benefits include a reduction in both preload and afterload and improved oxygenation and reduced work of breathing

– Respiratory failure due to chest trauma or contusions responds well to NIV and may improve mortality compared with ‘standard treatment.

– The use of NIV in recently extubated patients provides an attractive alternative to MV and may improve outcomes and mortality

– Ater abdominal surgery, basal atelectasis, prolonged supine position, and diaphragmatic splinting may all Contribute to the development of postoperative respiratory failure. The use of NIV both prophylactically and as a treatment for hypoxic respiratory has been demonstrated to reduce reintubation rates and mortality in abdominal visceral surgery and cardiac surgery,

– In thoracic surgery, acute respiratory failure (ARF) after pneumonectomy or lobectomy confers a significant risk of poor outcome. NIV is safe and may reduce both reintubation rates and mortality in this at-risk surgical group.