B is for BreathingIrene Bouras

Anaesthetic SpR UCLH

the centre forAnaesthesia UCL

Pre-Operative Considerations

• Assessment of respiratory function– History– Examination– Investigations

• Functional assessment is the most important

Pre-Operative Considerations

• Assessment of respiratory function– History– Examination– Investigations

• Functional assessment is the most important• Will they be difficult to ventilate? • What are your options?

Optimising Respiratory Function

Intra-operative

• Pre-operative monitoring & IV access• ?Pre-oxygenation• Induction of anaesthesia

Intra-operative

• Pre-operative monitoring & IV access• ?Pre-oxygenation• Induction of anaesthesia

ApnoeaAirway obstruction

Take over ventilation & secure airway

Intra-operative Ventilation

Spontaneous• Don’t need to stop & start

breathing• RR good guide to degree of

pain

BUT

• Prone to hypoventilation

IPPV• Prevent atelectasis• Can control ETCO2

BUT

• Can cause barotrauma & volutrauma

• Higher risk of awareness

Monitoring Ventilation

Patient Parameters

Monitoring Ventilation

Ventilator Parameters

Monitoring

Oxygen Saturations• Monitors oxygenation

not ventilation

End-Tidal CO2

• Measures adequacy of ventilation

• Confirms circuit is intact & that patient has CO

•Tidal Volume 8-10mls/kg

•Frequency 10-12/min•FiO2

Post- Operative

• Respiratory compromise may be caused by many factors– Patient factors: pre-existing lung disease– Anaesthetic factors: high epidural, high dose

opiates– Surgical factors: diaphragmatic splinting

• May need to keep some patients intubated on ICU post-op

Summary

• A good pre-operative assessment is essential• Get respiratory function as good as possible

pre-op• If you’re worried about ventilation intra-

operatively the monitors should give you an idea where the problem lies