Invasive ventilation

1
Invasive ventilation

• P Ramnarayan, Consultant, CATS/ SMH
• Simon Nadel, Consultant, SMH
• Lynn Shields, ANP, CATS

2
Invasive ventilation

• Induction agents
• Endotracheal tubes
• Ventilatory modes
• Initial settings
• Monitoring ventilation
• Weaning and extubation

3
Induction agents

• Thiopentone
• OK when CVS stable
• 2-5 mg/kg
• Good for raised ICP
• Ketamine fentanyl
• Appropriate for CVS instability

4
Induction agents

• Propofol
• OK when CVS stable
• Inhalational agents
• Airway obstruction
• Asthmatic if adequate air entry

5
Endotracheal tubes

• Cuffed ETT
• Down to 3.5 mm
• Cuff uninflated
• Ideal for poor lung compliance or risk of
• Check cuff pressure

6
Endotracheal tubes

• Size (age/4)4
• Term neonate 3.5 mm
• Oral preferable
• Nasal contraindicated in many situations
• Fixation is important

7
(No Transcript)
8
Fixation of ETT
9
Ventilatory modes

• Set tidal volume
• Set peak pressure
• Controlled
• Assisted
• Both

10
Ventilatory modes

• Set tidal volume
• 6-8 ml/kg
• Avoid barotrauma (pressure regulated)
• Flow sensors for weight

11
Ventilatory modes

• Set pressures
• Ensure adequate chest rise
• Measure adequate tidal volume
• Monitoring ventilation

12
PEEP

• High PEEP in pneumonitis
• Start at 6-8
• Titrate to FiO2 lt0.60
• Normal PEEP in asthma head injury
• Some ventilators no PEEP delivered

13
Initial settings

• Inspiratory time
• Neonate 0.3-0.4 s
• Infant 0.5-0.8 s
• Young child 0.75-1.0 s
• Older child 0.90-1.2 s

14
Initial settings

• PIP
• Adequate chest rise
• Poor compliance high pressures
• Can check with manometer and bagging
• PEEP
• 4-6 to start
• 6-8 if bad lung disease
• 8-10 if wet lungs

15
Initial settings

• Resp rate
• Neonate 40-60
• Infant 30-45
• Young child 20-40
• Older child 15-30

16
Monitoring

• CO2
• End tidal measurement
• VQ mismatch
• Poor cardiac output
• Leaky tube
• Blood gases
• Permissive hypercapnia

17
Monitoring

• O2
• SpO2
• PaO2
• PaO2/FiO2 ratio
• A-a DO2
• OI
• Target sats 88-95

18
Weaning

• Tied to sedation weaning
• Usually introduce assisted mode
• Pressure support
• Occasionally volume support
• Reduce PIP by 2, PEEP by 1-2
• Reduce rate by 5

19
Extubation

• Minimal vent settings
• Neurology satisfactory
• Stable haemodynamics
• Spontaneous breathing test used infrequently
• Extubation failure rate 5-8

20
Questions?