Perform a quick check of the anaesthetic machine:

1. Increase fresh gas flow and FiO₂
   This compensates for small leaks and should increase alveolar PO₂ (Fig 1)
2. Manual ventilation
3. Monitor check – FiO₂, CO₂, SpO₂
4. Check ventilator mode and settings are appropriate
5. Check airway pressure and flow monitoring

Perform a quick check of the anaesthetic machine:

1. Increase fresh gas flow and FiO₂
2. Manual ventilation
   Manual ventilation tests both the integrity of the fresh gas delivery system and the patient’s respiratory compliance (Fig 2)
3. Monitor check – FiO₂, CO₂, SpO₂
4. Check ventilator mode and settings are appropriate
5. Check airway pressure and flow monitoring

Perform a quick check of the anaesthetic machine:

1. Increase fresh gas flow and FiO₂
2. Manual ventilation
3. Monitor check – FiO2, ETCO2, SpO2 (Fig 3)
   1. FiO₂ - Analyzed in the breathing circuit as close to the patient    as possible
   2. Capnography - Gives immediate information, for example:
   
   • Flat line - Complete failure of ventilation
   • Notched trace - Patient respiratory effort during IPPV
   • Slow rising initial phase - Upper airway obstruction
   • Slow rising “plateau” phase - Bronchospasm
   3. SpO₂ - Though a late sign of ventilation failure
4. Check ventilator mode and settings are appropriate
5. Check airway pressure and flow monitoring

Perform a quick check of the anaesthetic machine:

1. Increase fresh gas flow and FiO₂
2. Manual ventilation
3. Monitor check – FiO₂, CO₂, SpO₂
4. Check ventilator mode and settings are appropriate (Fig 4)
5. Check airway pressure and flow monitoring

Perform a quick check of the anaesthetic machine:

1. Increase fresh gas flow and FiO₂
2. Manual ventilation
3. Monitor check – FiO₂, CO₂, SpO₂
4. Check ventilator mode and settings are appropriate
5. Check airway pressure and flow monitoring (Fig 5)
   A rising inflation pressure indicates a fall in compliance or an obstructive airway problem