NIV should be considered for use in patients with a persisting Acute Hypercapnic Respiratory Failures after a maximum of one hour of standard medical therapy.
- Complete the Ad-hoc form
- Increase pressures from Initial 12/5 cmH2O to 20/5cmH2O – as tolerated over 1st hour
However, ICU should be contacted early if the patient has one of the following:
- Asthma – Intubation the option of choice in Life threatening
- Pneumonia – NIV should only be considered as a bridge to intubation
- No pre-exisiting respiratory issue – NIV not likely helpful
- pH <7.25 (low threshold for ICU input)
- pCO2 >6.5kPa (low threshold for ICU input)
- Type 1 Respiratory Failure (low threshold for ICU input)
Practical
Using NIV – position 45°, correct mask
- IPAP – Starts 102cms H2O
- Titrated rapidly by 5cm/15min
- Target of 20cm H2O or therapeutic
- EPAP – 5cm H2O is recommended
- Oxygen – to achieve SpO2 of 88-92%
- ABG’s – after at 1, 4 and 12 hrs [minimum]
- Intubation decision – within 4 hrs of NIV
Contraindications
- Recent facial, upper airway or upper gastrointestinal* surgery
- Fixed obstruction of the upper airway
- Vomiting
- Inability to protect the airway*
- Copious respiratory secretions*
- Life threatening hypoxaemia*
- Severe co-morbidity*
- Confusion/agitation*
- Bowel obstruction*
- Pneumothorax [chest drain 1st]
*NIV can be used if contingency plans for tracheal intubation have been made, or if a decision has been made not to proceed to invasive ventilation.
