ALI/ARDS Zsolt Moln

1
ALI/ARDS Zsolt MolnárUniversity of SzegedAITI
2
Introduction

• ARDS is not a definitive illness
• Mortality 26 -74
• Furtos-Vivar F et al. Curr Opin Crit Care 2004
  10 1-6
• Definition Acute Lung Injury (ALI), ARDS
• Ashbaugh-1967, Murray-1988, American-European
  Consensus Conference on ARDS-1994, etc.

3
Pathophysiology

• Disorders associated with ARDS
• Primary
• Aspiration, inhalation
• Pneumonia
• Secondary
• Shock
• Infection
• Trauma
• Pancreatitis

4
Acute respiratory failure

• Classification
• Type I hypoxic
• Type II hypercapnic
• Mixed
• Participating factors
• Initial insult
• Inflammatory cascade
• Endothelium demage
• Non-cardiogenic pulmonary oedema
• Fibrosis

5
Diagnosis of severity

• CXR
• Atelectasis/quadrant 0-4
• PaO2/FiO2
• lt100 - 300lt 0-4
• PEEP (cmH2O)
• ?5 - 15? 0-4pont
• Compliance (ml/cmH2O)
• ?29 - ?80 0-4pont

• 2,5 ARDS
• 1,5-2,5ALI

Murray JF et al. Am Rev Respir Dis 1988 138
720-723
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Diagnostic signs

• Clinical
• Acute onset
• Tachypnea (gt30)
• Laboured breathing
• Physiologic
• Hypoxia (PaO2/FiO2lt250Hgmm)
• X-ray
• Bilateral infiltrates

7
Physiology, pathophysiology
8
Alveolar oxygenation
PAO2FiO2 x (PB-PH2O) PaCO2/R
PvO240 Hgmm
PAO2
120 Hgmm
PA-aO2 ? 20Hgmm
PaO2120 Hgmm
Molnár 99
9
Atelectasis and shunt
O2
PvO240 Hgmm
120 Hgmm
PaO2 (12040)/2 80 Hgmm
Molnár 99
10
Closing capacity (CC)

• In normal lungs
• CC in ERV
• FRCgtCC
• ALI/ARDS
• CC within VT
• FRCltCC

VT
ERV
FRC
CC
RV
CC
11
The degree of shunt
0
5
10
400
15
20

• Iso-shunt diagram
• Nunn JF. Appl. Resp Physiol., 1993

300
25
PaO2 Hgmm
200
30
100
50
0,2
0,6
1,0
FiO2
Molnár 99
12
Therapeutic dilemma

• Inflammed organs need rest
• IPPV life saving intervention
• WareLB, Matthay MA. N Engl J Med 2000 342
  1334-49
• IPPV if applied incorrectly can be deadly
• Tobin MJ. N Engl J Med 2001 344 1986-96

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Atelectasy and radiology
Gattinoni L, et al. Intensive Care Med 1986 12
137-142
14
Gary F. Nieman SUNY USA
Correlation between alveolar recruitment/derecruit
ment and inflection point on the pressure-volume
curve
DiRocco J, et al. Intensive Care Med 2007 33
1204-11
Normal lung
ARDS lung
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Alveolar recruitment
UIP
LIP
Open up the lung and keep it open! Lachmann B.
ICM 1992 18 319-321
Pelosi P, et al. AJRCCM 2001 164 122 Gattinoni
L, et al AJRCCM 2001 164 1701
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Ideal PEEP
Atelectasy
Overdistension
Increasing PEEP
Ideal PEEP moving tartget
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Physiology - revisited

• Breathing
• 15/min
• VT 4-7 ml/kg
• Ppleur 2-3 cmH2O
• FiO2 0.21
• Result
• PaO2 100 mmHg
• PaCO2 40 mmHg

Why?
Because its good for us!
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Case history

• 40 year old woman
• Committed sucide (20 tbl chlorpromazine)
• Ambulance Psychiatry
• Gastric lavage
• A few hours later acute abdominal pain
• Surgery
• Gastric perforation emergency surgery
• ICU

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Case history

• In a few days
• Secondary ARDS LISgt2.5
• FiO2 0.8
• PaO2 65 Hgmm
• PEEP 15 H2Ocm

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Hemodynamic and respiratory changes during lung
recruitment and descending optimal PEEP
titration in patients with ARDS
Tóth I, et al. Crit Care Med 2007 35 787-793
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Methods

• Lung recruitment
• Anaesthesia muscle relaxation
• PCV, IE11, RR 20/min
• FiO2 1.0
• PEEP 26 H2Ocm
• ?P 40 H2Ocm/40 sec

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Paninspiratory, tidal recruitment
Pelosi P, et al. AJRCCM 2001 164 122
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Paninspiratory, tidal recruitment
Pelosi P, et al. AJRCCM 2001 164 122
24
Methods

• Optimal PEEP titration
• Closing pressure
• Ideal PEEP when PaO2 gt 10
• VT4ml/kg
• PEEP 26-24-22/4 min

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Optimal PEEP

• Optimal PEEP titration
• PEEP0 15 H2Ocm - PaO2 276
• PEEP 26 H2Ocm - PaO2 436 Hgmm
• .
• PEEP 18 H2Ocm - PaO2 445 Hgmm
• PEEP 16 H2Ocm - PaO2 375 Hgmm

• Optimális PEEP 18 vízcm

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Outcome

• After PEEP titration
• Opening (40/40) at PEEP of 18
• Result
• FiO2 0.5 vs 0.8
• VT(6ml/kg) 350 vs 675 ml
• ?P 14 vs 20 H2Ocm
• PEEP 18 vs 15 H2Ocm
• PaO2 115 vs 62 Hgmm
• 40 days ICU Surgery Home

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Tidal volume VT
28
Volu-, or baro-trauma
large VT
small VT
29
Volu-, or baro-trauma
large VT
small VT
30
VT and inflammatory response

• Inflammatory response small VT vs large VT
• Reduced cytokine levels in BAL after 36 h
• Ranieri VM et al, JAMA 1999 28254
• Reduced plasma IL-6 on 3rd day on vent.
• ARDS Network, N Engl J Med 2000 342 1301

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VT and mortality

• No difference
• Brochard et al n116, VT10-15 vs 6-10 ml/kg
• Am J Respir Crit Care Med 1998 158 1831
• Stewart et al n120, VT10-15 vs 8 ml/kg
• N Engl J Med 1998 338 355
• Difference
• Amato n53, VT12 vs 6 ml/kg, M 28. nap 71 vs
  38
• N Engl J Med 1998 338347
• Network n861, VT12 vs 6 ml/kg, M 40 vs 31
• ARDS Network, N Engl J Med 2000 342 1301
• Network n549, 6 ml/kg, M 25
• ARDS Network, N Engl J Med 2004 351 327

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Other therapeutic consideration

• Supportive therapy
• Invasive haemodinamic monitoring
• Antibiotics
• Alternative therapies
• Prone positioning
• ECMO
• Nitric oxide (NO)
• Haemofiltration

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Summary

• ARDS is not a defintive diagnosis
• IPPV is against physiology
• Protect the lung
• Keep physiolology in mind

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Motto

• There is no substitute for the clinicians
• standing by the ventilator, making necessary
• adjustments and monitoring the effects of such
• adjustments.
• Tobin MJ, N Engl J Med 2000 3421360-1