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Breathing - NIV (single level)


Type 1 respiratory failure

Cardiogenic pulmonary oedema


Acute Lung injury

Post traumatic (rib fractures or contusions)

Severe respiratory failure requiring intubation

Peri-intubation oxygenation

Contraindications (absolute in bold)

The presence of relative contraindications necessitates a higher level of supervision and early appraisal of whether to progress to intubation and invasive mechanical ventilation.


Facial and airway burns or haemorrhage

Fixed upper airway obstruction (unless directly prior to intubation)

Reduced ability to protect airway (GCS <8, copious secretions)


Aerosolisation of high-risk microbes

Pneumothorax (without chest drain)


Haemodynamic compromise


Confusion or agitation

Cognitive impairment


Face mask or nasal prong oxygen

High flow humidified nasal prong oxygen

Intubation and mechanical ventilation

Informed consent

Medical emergency

Consent is not required if the patient lacks capacity or is unable to consent

Brief verbal discussion is recommended if the situation allows


Verbal consent

Less complex non-emergency procedure with low risk of complications

Potential complications



Mucus plugging

Gastric insufflation


Facial pressure areas



Procedural hygiene

Standard precautions

PPE: non-sterile gloves, surgical mask, eye protection, gown


Resuscitation bay


Procedural clinician and additional nurse


Correctly sized interface (full face or oronasal mask preferred)

Ventilator and circuit


Patient upright avoiding neck flexion


Morphine 2.5-5mg IV (symptomatic relief of agitation and distress)

Midazolam 0.5-2mg IV (symptomatic relief of agitation and distress)

Sequence (CPAP Setup)

Chest radiography or POCUS to exclude pneumothorax (do not delay initiation if not available)

Initial CPAP: 5cm water (or 1cm water per 10 kg body weight)

Place mask ensuring adequate seal

Titrate oxygen to achieve saturations >92%

Increases to CPAP: 2-5cm water every 10 minutes (maximum 12cm water)

Sequence (trouble shooting worsening saturations, respiratory rate or patient distress)

Improve mask fit and seal

Sit upright without excessive neck flexion

Treat precipitant (e.g. bronchospasm, pulmonary oedema)

POCUS to exclude pneumothorax

Low saturations (increase CPAP then increase oxygen to maintain stats >92%)

Patient still distressed (consider sedation)

Failing all the above (consider intubation or de-escalation (HFNP, Hudson mask, palliation)

Post-procedure care

Continuous monitoring with regular assessment of patient comfort and respiratory effort

Repeat VBG or ABG if clinical deterioration to exclude type 2 respiratory failure with acidosis

Document settings, tidal volume, saturation targets, escalation and failure plan


NIV in pneumonia and acute lung Injury is usually temporising measure


In pneumonia and acute respiratory distress syndrome with type 1 respiratory failure, we suggest CPAP is only used temporarily while preparing for intubation.

A randomised controlled trial of 123 patients with acute lung injury (61 with pneumonia) published in 2000 found no reduction in intubation or improved outcome with CPAP. In addition, CPAP appeared to delay intubation in some patients with adverse consequences. In the non-COPD population with community acquired pneumonia, non-invasive modes of respiratory support are unlikely to be successful. This is particularly the case in patients developing another organ failure.

Peer review

This guideline has been reviewed and approved by the following expert groups:

Emergency Care Institute

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