Lung Protective Strategies:Lung Protective Strategies:The Effects of Vt, PEEP & The Effects of Vt, PEEP &
Alveolar RecruitmentAlveolar Recruitment
David Grooms BS, RRTDavid Grooms BS, RRTSentara Norfolk General, Sentara Norfolk General,
Leigh & Bayside Leigh & Bayside HospitalsHospitals
Understanding ARDS…….Understanding ARDS…….2 Types2 Types
Extrapulmonary Extrapulmonary ARDS (In-direct)ARDS (In-direct)
Pulmonary ARDS Pulmonary ARDS (Direct)(Direct)
Identifying ARDS…….2 Types?Identifying ARDS…….2 Types?
Pulmonary ARDS Pulmonary ARDS (Direct)(Direct)
Pneumonia: Bacterial Pneumonia: Bacterial or Viralor Viral
Inhalation of noxious Inhalation of noxious agentagent
Aspiration of Gastric Aspiration of Gastric ContentsContents
Isolated pulmonary Isolated pulmonary contusioncontusion
Fat Embolus syndromeFat Embolus syndrome
Extrapulmonary Extrapulmonary ARDS (In-direct)ARDS (In-direct)
Multi-system TraumaMulti-system Trauma Transfusion related ALITransfusion related ALI Acute pancreatitisAcute pancreatitis SepsisSepsis Post- CABG surgeryPost- CABG surgery Hemorrahagic shockHemorrahagic shock
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
Characteristics of Extrapulmonary ARDS Characteristics of Extrapulmonary ARDS (In-direct)(In-direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present
Risk of Risk of overdistentionoverdistention
Recruitment Recruitment PotentialPotential
Response to PEEPResponse to PEEP
Characteristics of Extrapulmonary ARDS Characteristics of Extrapulmonary ARDS (In-direct)(In-direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present
Risk of Risk of overdistentionoverdistention
LowLow
Recruitment Recruitment PotentialPotential
Response to PEEPResponse to PEEP
Characteristics of Extrapulmonary ARDS Characteristics of Extrapulmonary ARDS (In-direct)(In-direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present
Risk of Risk of overdistentionoverdistention
LowLow
Recruitment Recruitment PotentialPotential
HighHigh
Response to PEEPResponse to PEEP Excellent (10-20 cm)Excellent (10-20 cm)
Characteristics of Extrapulmonary ARDS Characteristics of Extrapulmonary ARDS (In-direct)(In-direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present <10 cm often absent<10 cm often absent
Risk of Risk of overdistentionoverdistention
LowLow
Recruitment Recruitment PotentialPotential
HighHigh
Response to PEEPResponse to PEEP Excellent (10-20cm)Excellent (10-20cm)
Characteristics of Pulmonary ARDS (Direct)Characteristics of Pulmonary ARDS (Direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present <10 cm often absent<10 cm often absent
Risk of Risk of overdistentionoverdistention
LowLow HighHigh
Recruitment Recruitment PotentialPotential
HighHigh
Response to PEEPResponse to PEEP Excellent (10-20cm)Excellent (10-20cm)
Characteristics of Pulmonary ARDS (Direct)Characteristics of Pulmonary ARDS (Direct)
Viera et al. Am J Respir Crit Care Med 1998:158
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
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ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
# 60# 60
ARDS ARDS CT and PV Curve (slow inflation)CT and PV Curve (slow inflation)
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present <10 cm often absent<10 cm often absent
Risk of Risk of overdistentionoverdistention
LowLow HighHigh
Recruitment Recruitment PotentialPotential
HighHigh LowLow
Response to PEEPResponse to PEEP Excellent (10-20cm)Excellent (10-20cm)
Characteristics of Pulmonary ARDS (Direct)Characteristics of Pulmonary ARDS (Direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Contrasts between 2 types of ARDSContrasts between 2 types of ARDS
Kallet, R & Branson, R. Resp. Care Journal, Apr 2007, Vol 52 No 4
MechanicsMechanics Extrapulmonary Extrapulmonary ARDSARDS
Pulmonary ARDSPulmonary ARDS
Chest Wall Chest Wall ComplianceCompliance
ReducedReduced NormalNormal
Lung Compl.Lung Compl. ReducedReduced Severely ReducedSeverely Reduced
Lower inflec. PtLower inflec. Pt >10 usually present>10 usually present <10 cm often absent<10 cm often absent
Risk of Risk of overdistentionoverdistention
LowLow HighHigh
Recruitment Recruitment PotentialPotential
HighHigh LowLow
Response to PEEPResponse to PEEP Excellent (10-20cm)Excellent (10-20cm) Good (8-12cm)Good (8-12cm)
Characteristics of Pulmonary ARDS (Direct)Characteristics of Pulmonary ARDS (Direct)
Viera et al. Am J Respir Crit Care Med 1998:158
Effects of Mechanical/Physical Stretch Effects of Mechanical/Physical Stretch on Rat Alveolar Epithelial Cellson Rat Alveolar Epithelial Cells
Tschumperlin, D et al. Am J Respir Crit Tschumperlin, D et al. Am J Respir Crit Care Med, Vol 162. pp 357-362, 2000Care Med, Vol 162. pp 357-362, 2000
Excised Rat lungs Excised Rat lungs Placed Alveolar Epithelial Cells in a “cell-Placed Alveolar Epithelial Cells in a “cell-
stretching device”stretching device”
Tschumperlin, D et al. Am J Respir Crit Care Tschumperlin, D et al. Am J Respir Crit Care Med, Vol 162. pp 357-362, 2000Med, Vol 162. pp 357-362, 2000
Tschumperlin, D et al. Am J Respir Crit Care Tschumperlin, D et al. Am J Respir Crit Care Med, Vol 162. pp 357-362, 2000Med, Vol 162. pp 357-362, 2000
Both static and single deformations were significantly less injuriousthan cyclic deformations at each deformation level
Tschumperlin, D et al. Am J Respir Crit Care Tschumperlin, D et al. Am J Respir Crit Care Med, Vol 162. pp 357-362, 2000Med, Vol 162. pp 357-362, 2000
Reducing the amplitude reduced cell death
Cell Death dependent on frequency
ARDS NetworkARDS Network
ARDS NetworkARDS Network Multicenter, Randomized trialMulticenter, Randomized trial 861 Patients recruited from March 1996 through March 861 Patients recruited from March 1996 through March
1999 at 10 university centers.1999 at 10 university centers. Patients enrolled if:Patients enrolled if:
1) They were receiving mechanical ventilation 1) They were receiving mechanical ventilation 2) Had acute decrease in the P/F ratio (<300)2) Had acute decrease in the P/F ratio (<300)3) Bilateral pulmonary infiltrates on a chest radiograph 3) Bilateral pulmonary infiltrates on a chest radiograph consistent with the presence of edemaconsistent with the presence of edema4) No clinical evidence of left atrial hypertension or if 4) No clinical evidence of left atrial hypertension or if measure a PCWP<18mmHgmeasure a PCWP<18mmHg..
ResultsResults
Trial was stopped after fourth interim analysis.Trial was stopped after fourth interim analysis. Mortality ratesMortality rates
12 cc/Kg VT group- 39.8%12 cc/Kg VT group- 39.8% 6cc/Kg Vt group- 31.0% 6cc/Kg Vt group- 31.0%
Mortality decreased by 22%Mortality decreased by 22% Vt & Plat were significantly lowerVt & Plat were significantly lower Question to you- Question to you- What group had better PaO2’s?What group had better PaO2’s? 12 & they died more often- so better PaO2 does 12 & they died more often- so better PaO2 does
not translate into better outcomesnot translate into better outcomes
What did we do then?What did we do then?
We were skeptical at the results. Didn’t We were skeptical at the results. Didn’t like it because Vt was so low. like it because Vt was so low.
Also questioned that mortality could have Also questioned that mortality could have been better if more PEEP was used or use been better if more PEEP was used or use of Recruitment Maneuvers.of Recruitment Maneuvers.
Did we interpret the results of the studies Did we interpret the results of the studies right???right???
Lower PEEP/Higher FiO2
FiO2 .3 .4 .4 .5 .5 .6 .7 .7 .7 .8 .9 .9 .9 1.0PEEP 5 5 8 8 10 10 10 12 14 14 14 16 18 18-24
Higher PEEP/Lower FiO2
FiO2 .3 .3 .4 .4 .5 .5 .5-.8 .8 .9 1.0 PEEP 12 14 14 16 16 18 20 22 22 22-24
Recruitment Maneuver AttemptsRecruitment Maneuver Attempts
RM’s were performed on the first 80 patients RM’s were performed on the first 80 patients assigned to the higher PEEP group.assigned to the higher PEEP group.
1 or 2 manuevers per day @ 35-40cmH2O for 1 or 2 manuevers per day @ 35-40cmH2O for 30 seconds.30 seconds.
Mean increase in O2sat was “small & Mean increase in O2sat was “small & transient.” Therefore RM were DC’d for the transient.” Therefore RM were DC’d for the remainder of the trial.remainder of the trial.
ResultsResults
Trial stopped @ the 2Trial stopped @ the 2ndnd interim analysis after 549 interim analysis after 549 pts. Had been enrolled.pts. Had been enrolled.
Stopped based on the specified futility stopping Stopped based on the specified futility stopping rule.rule.
Surprising ResultsSurprising Results
Interpretation…..Interpretation….. PEEP does not improve PEEP does not improve
mortality of ARDS patients. mortality of ARDS patients. Added to our own confusionAdded to our own confusion Now what do we do if PEEP Now what do we do if PEEP
doesn’t help survivaldoesn’t help survival Instead of developing my Instead of developing my
own interpretation of the own interpretation of the results, I will wait around results, I will wait around until someone shows me until someone shows me the right way to do it.the right way to do it.
Do our dirty work for us!!!Do our dirty work for us!!!
So what can we do to try to do it So what can we do to try to do it right??right??
Question aspects of personal satisfaction vs. Question aspects of personal satisfaction vs. patient overall satisfactionpatient overall satisfaction
VS
I got the PaO2 up from 70-80 by turning the Vt up to 1200cc. You know I am
the man right?
Wow, awesome job, I will try to get it higher
than you did today! You are the man
So what can we do to try to do it So what can we do to try to do it right??right??
Example: Patient with ALI/ARDSExample: Patient with ALI/ARDSSteps to take to minimize progression of Steps to take to minimize progression of
syndromesyndromeMinimize FIO2, make all attempts to Minimize FIO2, make all attempts to
decrease FIO2 decrease FIO2 <<60%. 60%.
Oxygen Dissociation CurveOxygen Dissociation CurveARDSnet Study
88-94%PaO2 55-80
So what can we do to try to do it So what can we do to try to do it right??right??
Example: Patient with ALI/ARDSExample: Patient with ALI/ARDSSteps to minimize progression of Steps to minimize progression of
disease/syndromedisease/syndromeMinimize FIO2, make all attempts to Minimize FIO2, make all attempts to
decrease FIO2 decrease FIO2 <<60%. 60%. Management and consideration of VtManagement and consideration of Vt
Can mechanical ventilation actually Can mechanical ventilation actually produce lung injury?produce lung injury?
Webb & Tierney, 1974, Webb & Tierney, 1974, Am Rev Respir Dis 110:556-565Am Rev Respir Dis 110:556-565
Key Findings of the studyKey Findings of the study
1)1) Healthy Lungs with low PIP Healthy Lungs with low PIP does not cause lung injurydoes not cause lung injury
2)2) Ventilation with high PIP Ventilation with high PIP (30-45) & no PEEP (30-45) & no PEEP produces perivascular produces perivascular edema & leads to severe edema & leads to severe injury.injury.
3)3) PEEP provides protection PEEP provides protection from alveolar edema due to from alveolar edema due to high PIP.high PIP.
Webb & Tierney, 1974, Webb & Tierney, 1974, Am Rev Respir Dis Am Rev Respir Dis
110:556-565110:556-565
Overdistention/Increased Transalveolar Overdistention/Increased Transalveolar Pressure of Good alveoliPressure of Good alveoli Nieman, GNieman, G
Take HomeTake Home
Minimize Stretching of Healthy Alveoli by Minimize Stretching of Healthy Alveoli by reducing Vt or Plat pressure.reducing Vt or Plat pressure.
OK but what about patients that do not OK but what about patients that do not have ALI/ARDS??have ALI/ARDS??
Crit Care Med 2004 Vol. 32, No. 9
ResultsResults
VT’s above 9cc/Kg VT’s above 9cc/Kg cause VILI in non- cause VILI in non- ARDS patients.ARDS patients.
The incidence of The incidence of
VILI is higher in pts.VILI is higher in pts.
who get >9cc/Kgwho get >9cc/Kg
VT. & blood VT. & blood transfusions.transfusions.
What if I go too low on the Vt because I am trying to protect?
WOB & P0.1 comparison of pt. placed on low tidal volume strategy
0
1
2
3
4
5
6
7
8
1 101 201 301 401 501 601 701 801 901 1001 1101
# of Breaths
P0.1
(- v
alue
)
-0.2
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
WOB
(J/L
)
P01 (cmH2O) Wob (J/L) Linear (Wob (J/L)) Linear (P01 (cmH2O))
Pt. SwitchedTo AVTS Mode. Maintained @
8-9cc’s/Kg
Pt. Placed on 6cc/Kg Vt
Pt. Placed on 8-9cc/Kg Vt
Pt. Placed on 6cc/Kg VtSNGH Burn/Trauma Unit
So what can we do to try to do it So what can we do to try to do it right??right??
Example: Patient with ALI/ARDSExample: Patient with ALI/ARDSSteps to take to minimize progression of Steps to take to minimize progression of
syndromesyndromeMinimize FIO2, make all attempts to Minimize FIO2, make all attempts to
decrease FIO2 decrease FIO2 <<60%. 60%. Management and consideration of VtManagement and consideration of VtManagement of PEEPManagement of PEEP
How to set PEEP How to set PEEP
Use PEEP FIO2 table from ARDSnet Use PEEP FIO2 table from ARDSnet studystudy
FiO2 .3 .4 .4 .5 .5 .6 .7 .7 .7 .8 .9 .9 .9 1.0 PEEP 5 5 8 8 10 10 10 12 14 14 14 16 18 18-24
This table is designed to be appropriate for the average patient, but sometimes PEEP needs to be individualized
How to set PEEP How to set PEEP
Use PEEP FIO2 table from ARDSnet Use PEEP FIO2 table from ARDSnet studystudy
Set PEEP based off Lower Inflection point Set PEEP based off Lower Inflection point (pflex)(pflex)
Rimensberger P et al. CCM 1999;27:1940-1945Rimensberger P et al. CCM 1999;27:1940-1945
Crit Care Med 2006 Vol. 34, No. 5
Villar, et al. Crit Care Med 2006 Vol. 34, No. 5
Amato, M. et al. 1998. NEJM
Minimizing AtelectatictraumaMinimizing Atelectatictrauma(repeated opening and closing)(repeated opening and closing)
Nieman, G.
How to manage PEEP How to manage PEEP
Use PEEP FIO2 table from ARDSnet Use PEEP FIO2 table from ARDSnet studystudy
Set PEEP based off Lower Inflection point Set PEEP based off Lower Inflection point (pflex) +1-2cm(pflex) +1-2cm
Set PEEP based off Point of maximum Set PEEP based off Point of maximum Curvature or recruitable lung volume via Curvature or recruitable lung volume via deflation limb of PV curvedeflation limb of PV curve
The Effects of Recruitment on End-The Effects of Recruitment on End-expiratory Lung Volumeexpiratory Lung Volume
Barbas CSV Am J Respir Crit Care Med 2002;165:A218
APRV/HFOV puts pt. at this point
Figure 2
Pressure (cmH2O)
0 10 20 30 40 50 60
Vol
ume
(ml)
0
500
1000
1500
2000
2500
3000
Incremental PEEP10 cmH2O
IncrementalPEEP 20
IncrementalPEEP 25
DecrementalPEEP 15
DecrementalPEEP 10
DecrPEEP 5
Open-lung PEEP 18 cmH2O
Hickling K. AJRCCM 2001;163:69-78.
APRV/HFOV puts pt. at this point
Rimensberger P et al. CCM 1999;27:1940-1945Rimensberger P et al. CCM 1999;27:1940-1945
+350 cc’s
Maximizing a current modalityMaximizing a current modality
Not how much but HOW!Not how much but HOW!Pressure Modes: Use of Flow Time Pressure Modes: Use of Flow Time
pattern for adequate inspiratory phase to pattern for adequate inspiratory phase to improve gas distribution and minimize improve gas distribution and minimize level of pressure needed for ventilationlevel of pressure needed for ventilation
I-times in Pressure Modes for Full Flow deceleration improve gas distribution and
minimize PC level
F
T
P
T
MAP MAP
Vt Vt
I-times in Pressure Modes for Full Flow deceleration improve gas distribution and
minimize PC level
F
T
P
T
MAP
VtVt
F
T
P
T
MAP
Vt
Min.Insp. PressureAdjustments
Needed
Vt
Vt
I-times in Pressure Modes for Full Flow deceleration improve gas distribution and
minimize PC level
Maximizing a current or alternative Maximizing a current or alternative modalitymodality
Not how much but HOW!Not how much but HOW!Pressure Modes: Use of Flow Time Pressure Modes: Use of Flow Time
pattern for adequate inspiratory phase to pattern for adequate inspiratory phase to improve gas distribution and minimize improve gas distribution and minimize level of pressure needed for ventilationlevel of pressure needed for ventilation
Use of Airway Pressure Release Use of Airway Pressure Release Ventilation (APRV), HFOV, Jet VentilationVentilation (APRV), HFOV, Jet Ventilation
Normal Ventilation with Normal Normal Ventilation with Normal MAPMAP
P
Time
PEEP PEEP
Plat
PeakInsp
Mean InspPressure
Mean ExpPressure+ = MAP
5
20
15
Increase in Insp. PressureIncrease in Insp. PressureWhat will happen to MAP?What will happen to MAP?
P
Time
PEEP PEEP
Plat
PeakInsp
Mean InspPressure
Mean ExpPressure+ = MAP
5
20
15
25
Increase in Insp. PressureIncrease in Insp. PressureWhat will happen to What will happen to PlatPlat??
P
Time
PEEP PEEP
PlatPeakInsp
Mean InspPressure
Mean ExpPressure+ = MAP
5
20
15
25
Increase in PEEP, What will Increase in PEEP, What will happen to MAP & Plat?happen to MAP & Plat?
P
Time
PEEP PEEP
Plat
PeakInsp
Mean InspPressure
Mean ExpPressure+ = MAP
5
20
1510
APRV (Basically inverse Ratio with Spont. APRV (Basically inverse Ratio with Spont. Breathing during insp. Phase.) Can Increase Breathing during insp. Phase.) Can Increase
MAP and keep safe Plat. & spont. Breath.MAP and keep safe Plat. & spont. Breath.P
Time
PEEP PEEP
PlatPeak
Insp
Mean InspPressure
Mean ExpPressure+ = MAP
5
20
15
= If Flow isFully dec.
Spontaneous Breaths
SummarySummary Understand disease type, what is cause for Understand disease type, what is cause for
inflammation of the Lunginflammation of the Lung Manage FIO2 Manage FIO2 <<60% with PaO2 60% with PaO2 >>60mmHg & 60mmHg &
SpO2 SpO2 >>88%88% Manage Vt (4-8cc/KgIBW) & Plateau Pressure Manage Vt (4-8cc/KgIBW) & Plateau Pressure
<<30cmH2O to minimize stretch on good and bad 30cmH2O to minimize stretch on good and bad alveoli. >9cc/Kg IBW in non ARDS patients alveoli. >9cc/Kg IBW in non ARDS patients increases incidence of ALI developementincreases incidence of ALI developement
Commericial Vents actually incorporate an Commericial Vents actually incorporate an automatic Lung Protective Strategy (Hamilton automatic Lung Protective Strategy (Hamilton Galileo/ASV Mode & Drager Evita XL)Galileo/ASV Mode & Drager Evita XL)
SummarySummary
PEEP can be managed by multiple PEEP can be managed by multiple options, Goal is to prevent repeated options, Goal is to prevent repeated alveolar opening and closing, and proper alveolar opening and closing, and proper recruitment of dependent lung unitsrecruitment of dependent lung units
Alternative Modes can improve specific Alternative Modes can improve specific indices, but lack appropriate randomized indices, but lack appropriate randomized clinical trials for universal acceptanceclinical trials for universal acceptance
Optimize settings to improve gas Optimize settings to improve gas distribution on conventional modesdistribution on conventional modes
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me!!