control of breathing under mechanical ventilation...control of breathing under mechanical...
TRANSCRIPT
Control of Breathing Under Mechanical Ventilation
Ewan C. Goligher MD PhDInterdepartmental Division of Critical Care MedicineUniversity of Toronto
Disclosures
• Conflicts of Interest• Equipment and personal fees from Getinge• Equipment from Timpel
Outline
• Why we care: targeting respiratory effort• Control of ventilation• In non-ventilated subjects• On the ventilator
• Determinants of respiratory effort
Challenge: Managing Respiratory Drive
Respiratory drive & effort
P-SILI
Myotrauma
Respiratory drive and effort
Bertoni et al Crit Care 2019
Volutrauma
Myotrauma
Control of Ventilation
Vaporidi et al AJRCCM 2019
Control of Ventilation
Ve
PaCO2
PaCO2 =k ⋅V
.CO2
Ve.⋅ 1−Vd Vt( )
⇒Ve.=
1PaCO2
⋅k ⋅V
.CO2
1−Vd Vt( )
Control of Ventilation
Ve
PaCO2
PaCO2 =k ⋅V
.CO2
Ve.⋅ 1−Vd Vt( )
⇒Ve.=
1PaCO2
⋅k ⋅V
.CO2
1−Vd Vt( )
Control of Ventilation
Vaporidi et al AJRCCM 2019
PaCO2 =k ⋅V
.CO2
Ve.⋅ 1−Vd Vt( )
⇒Ve.=
1PaCO2
⋅k ⋅V
.CO2
1−Vd Vt( )
Control of Ventilation: Pattern
Ve
Vt
RR
Control of Ventilation: Respiratory Failure
Vaporidi et al AJRCCM 2019
Diaphragm dysfunction
Impaired mechanics
Control of Ventilation in Respiratory Failure
Vaporidi et al AJRCCM 2019
Ve
PaCO2
Control of Ventilation: Modes
Apneathreshold
Respiratory drive and effort
Bertoni et al Crit Care 2019
Volutrauma
Myotrauma
Determinants of Respiratory Muscle Pressure
Desired tidal volumeDesired inspiratory flow
Respiratory mechanics
Diaphragm function
Determinants of respiratory drive: sleep-wake status, acid-base, sedation, hypoxia, central demands
Ventilator pressure, flow, PEEP
Patient-Ventilator Interaction
Vaporidi et al AJRCCM 2019
Patient-Ventilator Interaction
Vaporidi et al AJRCCM 2019
Patient-Ventilator Interaction
Vaporidi et al AJRCCM 2019
Patient-Ventilator Interaction
Vaporidi et al AJRCCM 2019
Summary
• Why we care: targeting respiratory effort• Control of ventilation• In non-ventilated subjects• On the ventilator
• Determinants of respiratory effort