Table 2.

Contraindications and adverse events relating to NIV therapy

Absolute contraindications	Relative contraindications	Major adverse event	Transient physiological event
Cardiac or respiratory arrest	Mildly decreased level of consciousness	Anastomotic leak	Hypotension, defined as a decrease in blood pressure >20 mm Hg determined by pre/post blood pressure observations
Severe agitation or encephalopathy	Progressive severe respiratory failure as reported by the treating physician	Severe hypotension requiring increase in medical management	Decrease in SpO2 oxygen saturations >10% from baseline or<85% for >60 s
Undrained pneumothorax or intraoperative pneumothorax with ICC in situ	Uncooperative patient who can be calmed or comforted	Cardiac or respiratory arrest	Gastric distention as clinically reported by the treating surgeon
Uncontrolled vomiting	SpO2 falls below >10% below resting level of <85% for >60 s	Deterioration in medical condition requiring an increase in medical management	Vomiting during the NIV therapy
Inability to protect airway	MAP<target pressure despite vasopressor		Nasal bridge or facial erythema or ulceration
Severe upper GI bleeding or haemoptysis	Resting HR <50 or >140 or new untreated arrhythmia develops
Need for immediate intubation	RR <5 or >40 b/min
Facial trauma

HR, heart rate; ICC, intercostal catheter; MAP, mean arterial pressure; NIV, non-invasive ventilation; RR, respiratory rate; SpO₂, saturation of peripheral oxygen; upper GI, upper gastrointestinal.