1. Ventilatory Modes
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2. Mechanical Ventilation Goal
Generate a Minute Volume
Gases with a controlled FiO2
Avoiding:
Lung damage
Hemodynamic interference
Exesive Work of Breathing
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3. What is a Ventilatory Mode?
It´s the way in which the ventilator accomplish the goals of mechanical ventilation.
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4. Ventilatory Modes Classification
Control Variables
Control the inspiration
Constant behavior
Non controlled variable modification
PRESSURE Controlled Modes
FLOW Controlled Modes
VOLUME Controlled Modes
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5. Pressure Controlled Modes
The PRESSURE is the variable controlled by the
ventilator. It is constant during all Ti.
The ventilator try to reach and maintain a preset
inspiratory pressure
What happen with the non controlled variables?
Preset pressure
Respiratory impedance
Circuit impedance
Inspiratory effort
Volume and Flow
will change according
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6. Pressure controlled modes
Constant Pressure
Variable Flow
Flow /Time
Pressure/Time
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7. Flow Controlled Modes The FLOW is the controlled variable.
The VOLUME is also controlled in an indirect way: ( VT = Flow x Ti)
Rectangular – Decreasing ramp
Sinusoidal - Accelerated
The flow waveform can be changed
What happen with the non controlled variables?
Preset flow or volume
Respiratory impedance
Circuit impedance
Inspiratory effort
The airway PRESSURE
will change according:
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8. Flow Controlled Modes VariablePressure Constant Flow Pressure/Time
Flow/Time
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9. Volume Controlled Modes
Piston or bellows displacement
Controlled by a direct volume signal.
Modern ventilators control volume in an indirect way
by an integration of flow and time
Traditionally the flow controlled modes are also called
VOLUME controlled modes
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10. Volume or Flow Control Pressure Control
Variable Pressure
Constant Pressure
Constant volume
Variable volume
Constant inspiratory flow
Variable inspiratory flow
Volume or Flow
Control
Pressure Control
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11. Phase variables Trigger Time - Pressure – Flow – Volume
These are the signals used by the ventilator to determine
when a respiratory cycle phase must start or end
Trigger Time - Pressure – Flow – Volume
Limit Pressure – Flow - Volume
Cycling Time - Flow – Pressure – Volume
Base Pressure (PEEP)
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12. Phase Variables Pressure Control Ventilation mode Limit Cycling Base1 2 3 4 5 6
SEC
Paw
cmH2O 60
-20
120
INSP
EXH
Flow
L/min
Limit
Trigger
Cycling
Base
Phase Variables
Pressure Control Ventilation mode
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14. How a ventilator can be triggered? Respiratory Frecuency
It can be triggered by:
Time
(Controlled Ventilation)
Patient
(Assisted or Spontaneous Ventilation)
Respiratory Frecuency
Sensitivity
Pressure or Flow
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15. Where to look? Assisted Controlled (Pressure or Flow) (Time)
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16. Pressure trigger Pressure Which one is the most sensitive setting ?
Which one is the most
sensitive setting ?
-0.5 or -10
Trigger
(Sensitivity)
Pressure
Patient´s
effort
Sensitivity tthreshold
Post trigger response
(Ventilator´s flow)
Baseline
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17. Which one is the most sensitive setting?
Flow trigger
WITH patient
effort
Patient
NO patient
Sensitivity: 1 L/min 4 3
Setting: from 0.5 to 15 L/min
Which one is the most sensitive setting?
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18. Cycling (End of inspiration)
Volume controlled mode
Pressure Controlled modes
(PSV)
Cycling
(End of inspiration)
Volume
Flow
Time
(PCV)
(VCV)
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19. PEEP Positive End Expiratory Pressure
Restore FRC
Avoid alveolar collapse
Improve V/Q ratio
Correct Hipoxemia
Improve trigger with AutoPEEP
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20. Conditional Variables
Variables analyzed by the ventilator´s logic control and used to determine some criteria used to manipulate any phase of the respiratory cycle
Use sentences “ IF THEN “
“Closed Loop” Modes
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21. Respiratory Period Inspiration (Ti) Expiration (Te) (Ti/Tot) End Inspi
Trigger
Pause
Inspiration
(Ti)
Expiration
(Te)
Inspiratory
Flow
Expiratory
Flow
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22. According the Control Variable
Ventilatory Modes
According the Control Variable
Flow or Volume Controlled Modes
Pressure Controlled Modes
Dual Controlled Modes
(non conventional)
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23. Type of breathing Mandatory Breath
Started by the ventilator or the patient and ended by the ventilator.
Sponteneous Breath
Started and ended by the patient
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24. Graphnet Ventilator

25. PRVC Pressure Regulated Volume Control
Dual Control mode
Pressure Control with a target VT
Assist/Control
Maximum Limit: Pmax – 5 cmH2O
Minimun PCV 5 cmH2O
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26. VCV asist/control Volume Controlled Ventilation
Trigger: patient (assist) or time (control)
Pressure: variable and influenced by the
patient´s respiratory mechanics. Risk of
excessive alveolar pressure
Volume: preset and guaranteed
Cycling: volume
Inspiratory Flow: Controlled and fixed
Possibility to change the waveform
It can generate patient-ventilator asynchrony
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27. Different waveforms . Volume Control Ventilation Paw Vt V Square or
rectangular
Decreasing ramp
Sinusoidal
Paw Vt V .
Volume Control Ventilation
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29. VCV The most common problem…..
Disadvantages
Excessive pressure
Asynchrony
Increased WOB
Advantages
Experience
VE Guaranteed
and predictable
The most common problem…..
Mismatch between patient´s demand and inspiratory flow
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30. VE VT
(set)
Flow Ti F Te
Period
I : E
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31. Flow set: Ti set: Flow / 2 Ti x 2 Flow x 2 Ti / 2 I:E is modified
Ti / Flow x 2
Ti x Flow / 2
I:E is modified
Te: Frecuency x Te / I:E is modified
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32. PCV asist/control Pressure Controlled Ventilation
Trigger: patient or time
Pressure: controlled and preset
Less risk of barotrauma
Cycling: time
Volume : variable and influenced by the patient´s respiratory mechanics and effort , the preset pressure and Ti.
Inspiratory flow: variable and decelerated
Influenced by the respiratory mechanics
Deceleration is close related to Time Constant
Improves patient-ventilatos synchrony
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34. VE Ti Te I : E Raw VT F.R. CT Crs Rise Time P PEEP (set) MAP P
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35. “Rise Time”
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36. Pressure Controlled Modes
Modes: PCV and PSV
Disadvantages
VT variable
VE unpredictable
VT influenced by impedance
Advantages
Mean pressure
Barotrauma
Better distribution
WOB
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37. Pressure Support Ventilation
PSV
Pressure Support Ventilation
Trigger: patient only
Pressure: controlled and preset
Less risk of barotrauma
Volume : variable and influenced by the patient´s respiratory mechanics and effort , the preset pressure and Ti.
Inspiratory flow: variable and decelerated
Influenced by the respiratory mechanics
Deceleration is close related to Time Constant
Improves patient-ventilatos synchrony
Cycling: Flow (default)
Pressure (safety), Time (safety)
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39. PSV Variable End Inspiration criteria (Expiratory Sensitivity)
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40. PSV Advantages Disadvantages Similar to PCV
Work of breathing reduction
Better synchrony
Less sedation requirements
Disadvantages
Variable volume
Asynchrony in some COPD patients
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41. Sinchronized Intermitent Mandatory Ventilation
(SIMV)
Synchronized combination of mandatory and spontaneous breaths.
The mandatory breaths are delivered according the preset respiratory frecuency and they are synchronized with the patient´s respiratory effort
The patient determines the tidal volume and the frequency of the spontaneous breaths
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44. Graphnet Ventilator

45. Ventilation Mandatoria Intermitente
(SIMV)
Respiración mandatoria VCV
Respiración espontánea
con CPAP 0
con Presión de Soporte
SIMV VCV + CPAP 0
SIMV VCV + PSV
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46. CPAP Inspiration Paw (cmH2O) Expiration Graphnet Ventilator sec 16 148 10 12 14 16
Paw (cmH2O)
sec
Expiration
Inspiration
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47. Graphnet Ventilator

48. CPAP The patient must have spontaneous breaths.
This is not a respiratory support mode
Same physiological effects that PEEP.
Tidal volume and frecuency determined by the patient
Commonly used as a pre extubation test.
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49. Closed Loop Modes Mandatory Minute Volume PRVC
Inter breath dual control
Pressure controlled and flow cycled
Similar to PRVC, but with a VE target
PRVC
Pressure controlled and time cycled with a VT target
PSV + Assured Tidal Volume
Intra breath dual control
PSV with a MINIMUM tidal volume as target
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50. Graphnet Ventilator

51. PSV + Assured Tidal Volume
Constant Pressure (Pressure Controlled phase)
Variable Pressure (Flow Controlled phase)
Transition point
Decelerated Flow (pressure Controlled phase)
Continuous Flow (Flow Controlled phase)
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54. PRVC Pressure Regulated Volume Control
Dual Control mode
Pressure Control with a target VT
Assist/Control
Maximum Limit: Pmax – 5 cmH2O
Minimun PCV 5 cmH2O
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57. APRV 2 levels of CPAP with intermitent pressure release.
Spontaneous breaths
Higher Mean pressure
CO2 removal.
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58. Graphnet Ventilator

59. APRV Two CPAP levels (Hi and Lo)
Intermitent pressure release toward a lower pressure level
Two different CPAP times (TiHi and TiLo)
Spontaneous breaths possible in any moment of the respiratory cycle (Active Expiratory Valve)
PSV can be added to spontaneous breaths
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60. APRV Advantages Better gaseous exchange Dead space reduction
Less sedation requirements
Better hemodynamics
Less risk of barotrauma
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61. Ventilatory
Modes