Transcript of Mechanical Ventilation. Trigger All breaths on a ventilator need to be triggered.
- Slide 1
- Mechanical Ventilation
- Slide 2
- Trigger All breaths on a ventilator need to be triggered
- Slide 3
- Trigger All breaths on a ventilator need to be triggered They
can be Time triggered
- Slide 4
- Trigger All breaths on a ventilator need to be triggered They
can be Time triggered Patient triggered
- Slide 5
- Trigger All breaths on a ventilator need to be triggered They
can be Time triggered Patient triggered Flow triggered
- Slide 6
- Trigger All breaths on a ventilator need to be triggered They
can be Time triggered Patient triggered Flow triggered Pressure
triggered
- Slide 7
- Time triggering Time triggering means the ventilator starts the
breath
- Slide 8
- Time triggering Time triggering means the ventilator starts the
breath This will happen when there is no patient effort
- Slide 9
- Time triggering Time triggering means the ventilator starts the
breath This will happen when there is no patient effort This is
based on the set respiratory rate
- Slide 10
- Patient Triggering A breath can be triggered by the
patient
- Slide 11
- Patient Triggering A breath can be triggered by the patient
Flow triggering is the most common
- Slide 12
- Patient Triggering A breath can be triggered by the patient
Flow triggering is the most common Pressure triggering is another
option
- Slide 13
- Flow Triggering Flow triggering starts with a base flow This
flow is continuously flowing through the circuit
- Slide 14
- Flow Triggering Flow triggering starts with a base flow This
flow is continuously flowing through the circuit The ventilator
knows how much flow is going through the circuit The liter flow
leaving the ventilator should be the same as the liter flow coming
back
- Slide 15
- Flow Triggering As the patient inhales some of the flow goes
into the patient lungs This means less flow is returning to the
ventilator The ventilator senses that as a patient effort and
starts a breath
- Slide 16
- Flow Triggering The difference in the flow coming out of the
ventilator and coming back to the ventilator is how sensitivity is
determined The less flow needed to be deflected by the patient the
more sensitive it is The more flow needed to be deflected by the
patient the more difficult it is to trigger, i.e. less
sensitive
- Slide 17
- Flow Triggering 10 lpm is leaving the ventilator 10 lpm is
returning to the ventilator As a patient inhales and takes in 2 lpm
8 lpm is returning to the ventilator This reduction in returned
flow tells the ventilator to start a breath
- Slide 18
- Flow Triggering If you increase the amount of flow needed to be
inhaled by the patient the less sensitive the machine is 10 lpm is
leaving the ventilator 10 lpm is returning to the ventilator As a
patient inhales and takes in 4 lpm 6 lpm is returning to the
ventilator
- Slide 19
- Pressure Triggering Negative pressure is generated when a
patient inhales
- Slide 20
- Pressure Triggering Negative pressure is generated when a
patient inhales This negative pressure is in both the patients
lungs and the ventilator circuit
- Slide 21
- Pressure Triggering Negative pressure is generated when a
patient inhales This negative pressure is in both the patients
lungs and the ventilator circuit The ventilator senses the negative
pressure as a patient effort and starts a breath
- Slide 22
- Pressure Triggering So the patient needs to generate -2cmH2O to
start a breath If you increase the amount of negative pressure
needed the more difficult it is for the patient to trigger, i.e.
less sensitive
- Slide 23
- Limiting Limiting is what contols are in effect during the
inspiratory phase
- Slide 24
- Limiting Limiting is what contols are in effect during the
inspiratory phase After a breath is initiated certain limits will
be in effect depending on which type of breath is being
delivered
- Slide 25
- Limiting Limiting is what contols are in effect during the
inspiratory phase After a breath is initiated certain limits will
be in effect depending on which type of breath is being delivered
Limiting factors are what define a type of breath
- Slide 26
- Limiting Limiting is what contols are in effect during the
inspiratory phase After a breath is initiated certain limits will
be in effect depending on which type of breath is being delivered
Limiting factors are what define a type of breath The two most
common limits are
- Slide 27
- Limiting Limiting is what contols are in effect during the
inspiratory phase After a breath is initiated certain limits will
be in effect depending on which type of breath is being delivered
Limiting factors are what define a type of breath The two most
common limits are Pressure
- Slide 28
- Limiting Limiting is what contols are in effect during the
inspiratory phase After a breath is initiated certain limits will
be in effect depending on which type of breath is being delivered
Limiting factors are what define a type of breath The two most
common limits are Pressure Flow
- Slide 29
- Pressure Limited Pressure limited breaths have a set peak
airway pressure
- Slide 30
- Pressure Limited Pressure limited breaths have a set peak
airway pressure The pressure in the patients lungs will not go over
the set pressure
- Slide 31
- Pressure Limited Pressure limited breaths have a set peak
airway pressure The pressure in the patients lungs will not go over
the set pressure The following breaths are pressure limited
- Slide 32
- Pressure Limited Pressure limited breaths have a set peak
airway pressure The pressure in the patients lungs will not go over
the set pressure The following breaths are pressure limited PCV PSV
PRVC
- Slide 33
- Pressure Limited Pressure Control Ventilation (PCV) Pressure is
set with the intention of reaching the peak pressure and holding
the pressure for part of the inspiratory time
- Slide 34
- Pressure Limited Pressure Control Ventilation (PCV) Pressure is
set with the intention of reaching the peak pressure and holding
the pressure for part of the inspiratory time Pressure Support
Ventilation (PSV) Pressure is set to augment a patients own tidal
volume
- Slide 35
- Pressure Limited Pressure Control Ventilation (PCV) Pressure is
set with the intention of reaching the peak pressure and holding
the pressure for part of the inspiratory time Pressure Support
Ventilation (PSV) Pressure is set to augment a patients own tidal
volume Pressure Regulated Volume Control (PRVC) Pressure changes
with each breath with the intention of reaching a specific
volume
- Slide 36
- Flow Limited Flow limiting is used when a specific volume needs
to be delivered
- Slide 37
- Flow Limited Flow limiting is used when a specific volume needs
to be delivered Each breath has a rigid flow rate and pattern that
will deliver the specific volume
- Slide 38
- Flow Limited Flow limiting is used when a specific volume needs
to be delivered Each breath has a rigid flow rate and pattern that
will deliver the specific volume Therefore the breath is limited to
a predetermined flow Volume Control is a type of flow limited
breath
- Slide 39
- Pressure vs. Flow Limiting Pressure limited breaths have a
variable flow which allows better gas distribution
- Slide 40
- Pressure vs. Flow Limiting Pressure limited breaths have a
variable flow which allows better gas distribution The pressure is
limited therefore if lung conditions change the volume will
change
- Slide 41
- Pressure vs. Flow Limiting Pressure limited breaths have a
variable flow which allows better gas distribution The pressure is
limited therefore if lung conditions change the volume will change
If lungs become stiffer the volume will go down as the pressure
remains the same
- Slide 42
- Pressure vs. Flow Limiting Flow limiting will deliver a volume
no matter what the lung conditions
- Slide 43
- Pressure vs. Flow Limiting Flow limiting will deliver a volume
no matter what the lung conditions Volume will be consistent but
pressures will change
- Slide 44
- Pressure vs. Flow Limiting Flow limiting will deliver a volume
no matter what the lung conditions Volume will be consistent but
pressures will change If the lungs become stiffer the pressures
will go up
- Slide 45
- Pressure vs. Flow Limiting PRVC uses pressure limiting but will
automatically adjust the pressure to deliver a volume
- Slide 46
- Pressure vs. Flow Limiting PRVC uses pressure limiting but will
automatically adjust the pressure to deliver a volume So the
pressure is not set, the volume is set
- Slide 47
- Pressure vs. Flow Limiting PRVC uses pressure limiting but will
automatically adjust the pressure to deliver a volume So the
pressure is not set, the volume is set The ventilator will adjust
the pressure to achieve the volume
- Slide 48
- Pressure vs. Flow Limiting PRVC uses pressure limiting but will
automatically adjust the pressure to deliver a volume So the
pressure is not set, the volume is set The ventilator will adjust
the pressure to achieve the volume This allows for the variable
flow which is better for gas distribution
- Slide 49
- Pressure vs. Flow Limiting PRVC uses pressure limiting but will
automatically adjust the pressure to deliver a volume So the
pressure is not set, the volume is set The ventilator will adjust
the pressure to achieve the volume This allows for the variable
flow which is better for gas distribution If the lungs become
stiffer the pressures will go up
- Slide 50
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale
- Slide 51
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale Most breaths are time cycled
- Slide 52
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale Most breaths are time cycled Any breath
type that requires a set Ti is time cycled These include the
following breath types
- Slide 53
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale Most breaths are time cycled Any breath
type that requires a set Ti is time cycled These include the
following breath types PRVC
- Slide 54
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale Most breaths are time cycled Any breath
type that requires a set Ti is time cycled These include the
following breath types PRVC PCV
- Slide 55
- Cycling Cycling is what determines how the breath will stop and
allow the patient to exhale Most breaths are time cycled Any breath
type that requires a set Ti is time cycled These include the
following breath types PRVC PCV Volume Control
- Slide 56
- Cycling Flow is also used to cycle a breath off
- Slide 57
- Cycling Flow is also used to cycle a breath off Pressure
Support Ventilation (PSV) is flow cycled
- Slide 58
- Cycling Flow is also used to cycle a breath off Pressure
Support Ventilation (PSV) is flow cycled As the inspiratory flow
starts to slow down the ventilator will sense that the lungs are
getting full and cycle off allowing the patient to exhale
- Slide 59
- Cycling Flow is also used to cycle a breath off Pressure
Support Ventilation (PSV) is flow cycled As the inspiratory flow
starts to slow down the ventilator will sense that the lungs are
getting full and cycle off allowing the patient to exhale During
that same breath it is being pressure limited
- Slide 60
- Cycling Flow is also used to cycle a breath off Pressure
Support Ventilation (PSV) is flow cycled As the inspiratory flow
starts to slow down the ventilator will sense that the lungs are
getting full and cycle off allowing the patient to exhale During
that same breath it is being pressure limited So pressure is being
held in the lungs until the flow slows down at which time the
ventilator will release the pressure and the patient exhales
- Slide 61
- Baseline Baseline is what limits are in effect during
exhalation Exhalation is passive The only limit will be added
pressure, i.e. PEEP The baseline should be assessed via total PEEP
to accurately measure the baseline
- Slide 62
- Rise Time or Slope Rise time is part of the inspiration so
could be considered a limiting factor
- Slide 63
- Rise Time or Slope Rise time is part of the inspiration so
could be considered a limiting factor It is usually not included in
the definition of a breath
- Slide 64
- Rise Time or Slope Rise time is part of the inspiration so
could be considered a limiting factor It is usually not included in
the definition of a breath Rise time adjusts the initial flow rate
of a breath
- Slide 65
- Rise Time or Slope Rise time is part of the inspiration so
could be considered a limiting factor It is usually not included in
the definition of a breath Rise time adjusts the initial flow rate
of a breath It determines how much time is allowed for the breath
to reach the peak flow needed to deliver the breath in the allotted
time (Ti)
- Slide 66
- Rise Time/Slope The less time the Rise time is the faster the
breath ramps up to full speed
- Slide 67
- Rise Time/Slope The less time the Rise time is the faster the
breath ramps up to full speed The longer the Rise Time is the
slower the breath reaches peak flow
- Slide 68
- Rise Time/Slope So if you have an inspiratory time of 1 second
and you set your Rise Time at 0.2 seconds the peak flow will be
reached in 0.2 seconds creating a blast of air at the beginning of
the breath
- Slide 69
- Rise Time/Slope So if you have an inspiratory time of 1 second
and you set your Rise Time at 0.2 seconds the peak flow will be
reached in 0.2 seconds creating a blast of air at the beginning of
the breath If you increase the Rise Time to 0.5 seconds the breath
will not reach peak flow until half way through the breath creating
a slower overall flow
- Slide 70
- Rise Time/Slope A short Rise Time may be helpful in patient
with high inspiratory demands, such as asthma
- Slide 71
- Rise Time/Slope A short Rise Time may be helpful in patient
with high inspiratory demands, such as asthma A longer Rise Time is
usually more comfortable because there is not the blast of air at
the beginning
- Slide 72
- Rise Time/Slope A short Rise Time may be helpful in patient
with high inspiratory demands, such as asthma A longer Rise Time is
usually more comfortable because there is not the blast of air at
the beginning Where it is set is very patient dependent
- Slide 73
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath
- Slide 74
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath Pressure Support Ventilation (PSV)
- Slide 75
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath Pressure Support Ventilation (PSV) Flow cycling is
used to end a PSV breath
- Slide 76
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath Pressure Support Ventilation (PSV) Flow cycling is
used to end a PSV breath Normal inspiration goes to zero flow and
then reverses the flow to exhale
- Slide 77
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath Pressure Support Ventilation (PSV) Flow cycling is
used to end a PSV breath Normal inspiration goes to zero flow and
then reverses the flow to exhale Because it is difficult to achieve
a tight seal on the circuit and patient, it is impractical to
require the patient to get to zero flow before exhaling
- Slide 78
- Inspiratory Cycle Off Inspiratory cycle off is part of the flow
cycling breath Pressure Support Ventilation (PSV) Flow cycling is
used to end a PSV breath Normal inspiration goes to zero flow and
then reverses the flow to exhale Because it is difficult to achieve
a tight seal on the circuit and patient it is impractical to
require the patient to get to zero flow before exhaling Flow
cycling allow the breath to end prior to reaching zero flow
- Slide 79
- Inspiratory Cycle Off Some ventilators have a preset flow rate
that will cycle the PSV breath into exhalation
- Slide 80
- Inspiratory Cycle Off Some ventilators have a preset flow rate
that will cycle the PSV breath into exhalation Some ventilators
allow the flow rate to be adjusted
- Slide 81
- Inspiratory Cycle Off Some ventilators have a preset flow rate
that will cycle the PSV breath into exhalation Some ventilators
allow the flow rate to be adjusted When setting Inspiratory Cycle
Off it is a percentage
- Slide 82
- Inspiratory Cycle Off Some ventilators have a preset flow rate
that will cycle the PSV breath into exhalation Some ventilators
allow the flow rate to be adjusted When setting Inspiratory Cycle
Off it is a percentage The percentage is based on the peak
inspiratory flow achieved during the breath
- Slide 83
- Inspiratory Cycle Off Some ventilators have a preset flow rate
that will cycle the PSV breath into exhalation Some ventilators
allow the flow rate to be adjusted When setting Inspiratory Cycle
Off it is a percentage The percentage is based on the peak
inspiratory flow achieved during the breath The percent is what
determines when the breath will release the pressure and allow
exhalation
- Slide 84
- Inspiratory Cycle Off If you set the Inspiratory Cycle Off at
25% the inspiratory breath will end when the flow is 25% of the
peak flow during that breath
- Slide 85
- Inspiratory Cycle Off If you set the Inspiratory Cycle Off at
25% the inspiratory breath will end when the flow is 25% of the
peak flow during that breath If the peak flow was 60 lpm the breath
will end at 25% of that or 15 lpm
- Slide 86
- Inspiratory Cycle Off If you set the Inspiratory Cycle Off at
25% the inspiratory breath will end when the flow is 25% of the
peak flow during that breath If the peak flow was 60 lpm the breath
will end at 25% of that or 15 lpm The higher the % set the sooner
the breath will be cycled off
- Slide 87
- Inspiratory Cycle Off If you set the Inspiratory Cycle Off at
25% the inspiratory breath will end when the flow is 25% of the
peak flow during that breath If the peak flow was 60 lpm the breath
will end at 25% of that or 15 lpm The higher the % set the sooner
the breath will be cycled off This may cut off a patient breath
early