Lluís Blanch M.D., Ph.D. Consultant Critical Care Scientific Director Corporació Parc Taulí Universitat Autónoma de Barcelona Sabadell, Spain. Cairo 3 - 4 February 2010 Lung Mechanics Beyond Basics 10th Pulmonary Medicine Update Course
May 21, 2015
Lluís Blanch M.D., Ph.D.Consultant Critical Care
Scientific Director Corporació Parc TaulíUniversitat Autónoma de Barcelona
Sabadell, Spain.
Cairo 3 - 4 February 2010
Lung Mechanics Beyond Basics
10th Pulmonary Medicine Update Course
kC
VRVPaos Pr
Equation of motion
PeepiPelesPaos PrPr
Time
VCV. Effects of an End-Inspiratory Occlusion
Effect of Increasing Elastance during CF.VCVChange in the Slope of Pao(t) Curve
Lucangelo U, Bernabè F, and Blanch L. Resp Care 2005; 50 : 55-65
Time course of Airway Pressure During Constant-Flow Inflation
Albaiceta GM, Blanch L, Lucangelo U. Current Opinion in Crtical Care 2008 (in press)
Human ARDS
VT
PEEP
Obese patientStroke + Moderate ALI
FRCFRC
V V inducedinducedby PEEPby PEEP
Static P-V Curves at Different PEEPStatic P-V Curves at Different PEEP
Recruited Recruited lung volumelung volume
Nil recruitmentNil recruitmentat PEEP 20 at PEEP 20
Closing pressureClosing pressure
Pt # 1
0
300
600
900
1200
1500
1800
2100
0 10 20 30 40 50
Pel (cm H2O)
Vol
ume
(mL
)
Pt # 17
0
300
600
900
1200
1500
1800
2100
0 10 20 30 40 50
Pel (cm H2O)
Vol
ume
(mL
)
Pt # 14
0
300
600
900
1200
1500
1800
2100
0 10 20 30 40 50
Pel (cm H2O)
Vol
ume
(mL
)
Pt # 4
0
300
600
900
1200
1500
1800
2100
0 10 20 30 40 50
Pel (cm H2O)
Vol
ume
(mL
)
Maggiore S et al. AJRCCM 2001; 164: 795-801
0
500
1000
1500
2000
2500
0 5 10 15 20 25 30 35 400
500
1000
1500
2000
2500
0 5 10 15 20 25 30 35 40
0
200
400
600
800
1000
1200
0 5 10 15 20 25 30 35 40
0
100
200
300
400
500
600
700
800
900
1000
0 5 10 15 20 25 30 35 40
Paw (cmH2O)
Vol (ml)
2 1
3 4
Galileo Ventilator's Built-in PV Tool-2
Pressure/Time Ramp 3 cmH2O/s
Pressure/Time Ramp 5 cmH2O/s Piacentini E, Wysocki M, Blanch L.Intensive Care Med 2009.
Nahum A. Yearbook in Intensive Care Medicine. 1995.
Dynamic P-V Curves at Different Flows & Equal Tidal Volume
Inspiratory P-V Curves in ARDS Patients Inspiratory P-V Curves in ARDS Patients with Different CT Patternswith Different CT Patterns
Rouby et al. Intensive Care Med 2000;26:1046Rouby et al. Intensive Care Med 2000;26:1046
LobarLobar
DiffuseDiffuse
PatchyPatchy
Effect of Increasing Resistance during CF.VCVUpward Shift in the Pao(t) Curve
Airway Pressure
Tracheal Pressure
Blanch L et al. Am J Respir Crit Care Med 1995;151:A328
Partitioning of Rrs in Patients (CF.VCV)
Alveolar Heterogeneity during Histamine Challenge
AutoPEEP: Pendelluft Effect
Romero P, Lopez J, Blanch L. Pulmonary mechanics beyond peripheral airways. In: Milic_Emili J, ed. Applied Physiology in Respiratory Mechanics. Springer 1997; p.190-210.
Air TrappingAir Trapping
InspirationInspiration
ExpirationExpiration
NormalNormalPatientPatient
Time (sec)Time (sec)
Flo
w (
L/m
in)
Flo
w (
L/m
in)
Air TrappingAir TrappingAuto-PEEPAuto-PEEP
}}
BeforeBefore
Time (sec)Time (sec)
Flo
w (
L/m
in)
Flo
w (
L/m
in)
PEFRPEFR
AfterAfter
Long TLong TEE
Higher Higher PEFRPEFR
Shorter TShorter TEE
Response to BronchodilatorRajiv Dhand. Respiratory Care 2005 (February). Vol 50. Nº 2.
Response to BronchodilatorRajiv Dhand. Respiratory Care 2005 (February). Vol 50. Nº 2.
43210-1.0
-0.5
0.0
0.5
1.0
AutoPEEP
Time Time (s)(s)
AirflowAirflow(L/s)(L/s)
AutoPEEP Generation: Lengthen Ti at equal TtotAutoPEEP Generation: Lengthen Ti at equal Ttot(Airflow decreased for a similar VT)(Airflow decreased for a similar VT)
Blanch L, Bernabe F, Lucangelo U. Respir Care 2005;50:110-123
Lucangelo U, Bernabè F, and Blanch L. Resp Care 2005; 50 : 55-65Lucangelo U, Bernabè F, and Blanch L. Resp Care 2005; 50 : 55-65
Progressive increase of inspiratory pause during VCV
INTRINSIC PEEP (PEEPi) in static and dynamic conditions
Flow (l/s)
0
DynamicPEEPi (4cm H20)
TrachealPressure (cmH2O)
0
1
10
20
30
StaticPEEPi (8 cmH20)
END EXPIRATORY OCCLUSION
Respir Care 2005;50(1):110-123
Leatherman JW et al. Crit Care Med 1996; 24:541-546Leatherman JW et al. Crit Care Med 1996; 24:541-546
Expiratory Airway Occlusion in AsthmaExpiratory Airway Occlusion in AsthmaMeasured AutoPEEP = 5 cmHMeasured AutoPEEP = 5 cmH22OO
55
Mechanisms of Auto PEEP Generation
Vieillard-Baron A et al. Crit Care Med 2002; 30:1407-12Vieillard-Baron A et al. Crit Care Med 2002; 30:1407-12
Increasing Respiratory Rate in ARDSIncreasing Respiratory Rate in ARDS
AJRCCM 2000;161:1590-6
PEEP & AutoPEEP in COPD Patients
Blanch L, Fernandez R. In: Mancebo J, Brochard L, eds. Arnette 1996; 329-345.
Ventilator Waveforms at the Bedside
Displays of pressure, flow and volume, and
derived loops are available in the majority of
modern ventilators.
Ventilator waveforms are important to
understand basic respiratory pathophysiology,
and play a role in treatment decisions in
patients receiving mechanical ventilation.