Ventilator Induced Lung Injury. VIASYS Healthcare, Inc. Ventilator Induced Lung Injury Barotrauma...
-
Upload
norma-barber -
Category
Documents
-
view
236 -
download
3
Transcript of Ventilator Induced Lung Injury. VIASYS Healthcare, Inc. Ventilator Induced Lung Injury Barotrauma...
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Barotrauma
• Volutrauma
• Stretch Injury
• Biochemical Injury
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Barotrauma• Air leaking into
pleural space• Air leaking into
interstitial space (PIE)
• Tearing at Bronchio-Alveolar Junction as lung is recruited and allowed to collapse
• Most occurs in dependent lung zones (transition zone)
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Stretch Injury• Alters capillary
transmural pressures• Changes in transmural
pressure causes breaks in capillary endo and epithelium
• Increases leak of proteinacious material
• Promotes Atelectasis
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Rodents ventilated with three modes:• High Pressure
(45 cmH2O), High Volume
• Low Pressure (negative pressure ventilator), High Volume
• High Pressure (45 cmH2O), Low Volume (strapped chest and abdomen)
Dreyfuss,D ARRD 1988;137:1159
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Volutrauma• Caused by cycling of the
lung (change in surface area), independent of pressure required
• Alters Surfactant function• Promotes Atelectasis
• Increases capillary leak of proteinacious material
• Promotes Atelectasis
Dreyfuss,D ARRD 1988;137:1159
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Hyaline Membrane Disease is not really a disease, it’s the result of volume cycling the lungs
• CMV produces consolidation, over inflation and hyaline membrane formation
• HFOV uniformly inflates the lung without hyaline membrane formation
Meredith K, JAP 1989; 66:2150
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
Premature baboon model
Coalson J. Univ Texas San Antonio
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
Premature baboon model
Coalson J. Univ Texas San Antonio
VIASYS Healthcare, Inc.
Adult ARDS
• HFOV - Caring for the Baby in Adults• Baby Lung Sitting on
Top of a Consolidated Lung
• Tidal Volumes of 6-10 ml/kg based on weight
• Tidal Volumes of 20-50 ml/kg based on open lung units
• Histology is similar to infant lung injury
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Adult Acute Respiratory Failure– Atelectasis– Overdistended
airways and alveoli
– Cellular accumulation
– Hyaline Membranes Lamy ARRD 1976; 114:267
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Adult ARDS late stage lung structural changes• Enlarged air
space• Septal
destruction• Fibrotic lesions
VIASYS Healthcare, Inc.
ARDS Pulmonary Injury Sequence
• Phase 1 Early Exudative Treatment • Endo/Epithelial Damage• Type 1 Alveolar Cell Injury and/or Loss• Capillary Congestion• Interstitial/Alveolar Edema, Hemorrhage• Protein Accumulation• Surfactant Deactivation• Atelectasis• Hyaline Membrane Formation• Inflammatory Cell Migration• Volutrauma - Increased Protein Leak,
Atelectasis, etc.
VIASYS Healthcare, Inc.
ARDS Pulmonary Injury Sequence
• Phase 2 Proliferative (Day 5-10)• Proliferation of Type 2 Cells• Fibroblast Migration• Interstitial Collagen Formation• Increased Dead Space• Decreased Compliance• Increased Pulmonary Vascular Resistance
VIASYS Healthcare, Inc.
ARDS Pulmonary Injury Sequence
• Phase 3 Fibrotic (Day 10-14)• Lung Destruction• Emphysematous Changes• Fibrosis• Pulmonary Vascular Obliteration• Chronic Lung Disease
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Biochemical Injury• Biochemical agents
(mediators) attack the lung
• Recruit fibrotic proliferation cells to the lung
• Atelectasis promotes release of chemical mediators
• Mediators released in the lung can attack other organ systems
• Cells• Macrophages• Endothelial and
Epithelial Cells• Platelets• Neutrophils
• Mediators• Cytokines• Leukotrienes• PAF (Platelet
Activating Factor)• Thromboxane• TNF (Tumor
Necrotizing Factor)• Complement
Proteins• Interleukin-1,8
VIASYS Healthcare, Inc.
Pulmonary Injury Sequence
• There are two injury zones during mechanical ventilation• Low Lung Volume
Ventilation tears adhesive surfaces
• High Lung Volume Ventilation over-distends, resulting in “Volutrauma”
• The difficulty is finding the “Sweet Spot”
Froese AB, Crit Care Med 1997; 25:906
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
Twenty Years of One Year Follow Up of Lung Function (DLCO) in ARDS Survivors
Suchyta MR, ERS 1997
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• HFOV with Surfactant as Compared to CMV with Surfactant in the Premature Primate– HFOV resulted in
• Less Radiographic Injury
• Less Oxygenation Injury
• Less Alveolar Proteinaceous Debris
Jackson C AJRCCM 1994; 150:534
Alveolar Protein
0%
5%
10%
15%
20%
25%
30%
CM
V
CM
V-S
HF
OV
HF
OV
-S
Mode
Per
cen
t D
ebri
s
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• High Lung Volume Strategies with HFOV• Extended Surfactant
Activity• Normalized Lamellar
Body Phospholipid levels• Improved lung mechanics
• All Conventional Ventilator Strategies• Resulted in Death or
Decreased Surfactant Performance
Froese A, ARRD 1993; 148:569
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
Control animal histology
Sugiura M, JAP 1994; 77:1355
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
HFOV animal histology
Sugiura M, JAP 1994; 77:1355
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
CMV animal histology
Sugiura M, JAP 1994; 77:1355
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• HFOV Stimulates Significantly Less Neutrophil Activity Than CMV
• Neutrophil Activity Has a Role in the Genisis of ARDS, Releasing Active Oxygen Species, Proteinases and Arachidonic Acid Metabolites.
Sugiura M, JAP 1994; 77:1355
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• HFOV produces less inflammatory markers than CMV Imai Y, AJRCCM 1994; 150:1550
VIASYS Healthcare, Inc.
Ventilator Induced Lung Injury
• Activation of alveolar macrophages and pro-inflammatory cytokines play a pivotal role in Ventilator Induced Lung Injury
Takata M, AJRCCM 1997; 156:272
VIASYS Healthcare, Inc.
Risk Factors for ARDS
• Trauma• Shock Syndromes - Sepsis, Cardiogenic• Gastric Aspiration • Burns• Diffuse Pneumonias• Near Drowning• Drug Overdose• Metabolic Events - Pancreatitis, Uremia• Systemic Mediator Release Associated Diseases
– Disseminated Intravascular Coagulopathy– Cardiopulmonary Bypass -- Anaphylaxis– Extrapulmonary Infection -- Transfusion
Reaction
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT (10 scans/sec)
Weiler N. et al, 1999, personal communication
30 kg Pig
Pre Lavage
Pressure Control Ventilation
Paw 13 cmH2O PEEP 5 cmH2O
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT (10 scans/sec)
Weiler N et al, 1999, personal communication
30 kg Pig
Pre Lavage
Pressure Control Ventilation
Paw 23 cmH2OPEEP 15 cmH2O
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT (10 scans/sec)
Weiler N et al, 1999, personal communication
30 kg Pig
Post Lavage
Pressure Control Ventilation
Paw 13 cmH2O PEEP 5 cmH2O
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT (10 scans/sec)
Weiler N et al, 1999, personal communication
30 kg Pig
Post Lavage
Pressure Control Ventilation
Paw 23 cmH2OPEEP 15 cmH2O
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT (10 scans/sec)
Weiler N et al, 1999, personal communication
30 kg Pig
Post Lavage
Pressure Control Ventilation
Paw 33 cmH2OPEEP 25 cmH2O
VIASYS Healthcare, Inc.
Lung Inflation PatternsMulti-Scan CT(10 scans/sec)
30 kg PigPost LavageHFOV Paw 23 cmH2O
Weiler N. Heinrichs W, et al 1999