Presented by Dr.Lllis Blanch at 8th Pulmonary Medicine Update Course 2008 held at Cairo, Egypt. (www.scribeofegypt.com)

1. 8th Pulmonary Medicine Update Course
The Egyptian Society of ICM & Trauma
Medical & Surgical ARDS:
Are the Same ?
Lluis Blanch M.D.
Consultant, Critical Care Center, Hospital of Sabadell
Scientific Director, Corporacio Parc Tauli
University Institut Fundació Parc Taulí
Universitat Autónoma de Barcelona
Sabadell, Spain
lblanch@tauli.cat
Cairo, February 6 - 7, 2008

2. Diagnostic Criteria for ARDS
Fan E, et al. JAMA 2005;294:2889-96

3. American–European Consensus Conference Definition and
Sensitivity, Specificity, and Likelihood Ratios Assessed in Patients
Who Died in the Intensive Care Unit
Reference Standard: Diffuse Alveolar Damage at Autopsy
The accuracy of the American–European Consensus Conference definition of
ARDS was only moderate. The definition was more accurate for patients
with extrapulmonary risk factors than for patients with pulmonary risk factors.

4. ! #
quot; $
$ % ! #
quot; $
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Pelosi P, et al. Acta Clinica Belgica 2007; 62;78-88

5. IAP 7 ± 3 cmH2O IAP 24 ± 5 cmH2O
IAP ! /quot; . 0 1 2 35.
0 ) . )4 .

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, : ;+
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+< += > ?+ +
@ (! A
% quot;
<
1 B 34 52 .
''* . 02 * *
% <! /
(
, 86 7
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7. Impairment in Chest Wall Mechanics
Clinical Criteria :
Abdominal distension
Abdominal surgery
Abdominal binding
Chest wall abnormalities
Pleural effusions
Laparoscopic procedures
Anasarca
Intestinal meteorism & obstruction
Obesity
Ascitis
Burns

8. Ranieri et al., Am J Respir Crit Care Med 1998; 156:1082-1091.

9. Surgical ARDS before & after laparotomy
RS CW Lung Abd

10. During Lung
Protective Ventilation:
PplatTM = Pplat – IAP/2
Normal Abdominal Wall Compliance
Poor Abdominal Wall Compliance

12. AJRCCM 2000;161:1485-94
Lavage Pneumonia
Responses to PEEP & VT differ among models of ALI

13. AJRCCM 2000;161:1485-94
OAI (extrapulmonary) Pneumonia
(pulmonary)
Responses to PEEP & VT differ among models of ALI

15. 71 ARDS patients:
29 pulmonary
16 extrapulmonary
26 uncertain group
Methods to Measure Recruitment P-V Curve: Recruitment with PEEP

16. PaO2 Vol. Rec. [Prot.]
RM Loss of Lung Aeration: Diffuse
Responders
RM Non
Responders
Loss of Lung Aeration: Focal

17. VT 7 ml/kg
PEEP 15 cmH2O

18. Patients r=-0.85
p<0.01
Am J Respir Crit Care Med 2002; 165: 165-170

19. Human ARDS
Direct
Indirect
Pulmonary
Extrapulmonary
Medical
Surgical
Primary
Secondary

20. ARDS:
What’s Important
Etiology
Time of Onset
Respiratory & Abdominal Mechanics
Gas Exchange
Avoid Ventilator-Induced Lung Injury
Avoid Excessive Muscle Workload

21. Observed Mortality According to the Quintile of
Dead-Space Fraction in 179 Patients with ARDS
Mechanisms:
1- Injury of pulmonary
capillaries by thrombotic and
inflammatory factors.
2- Obstruction of pulmonary
blood flow in pulmonary
circulation.
3- Lung areas with high V/Q
ratio (impaired CO2 excretion)
Nuckton TJ et al. N Engl J Med 2002; 346:1281.

22. PCO2
PaCO2
Phase III
PetCO2 20.0
50 samples
15.0
VCO2 (ml)
Phase II 10.0
5%
Effective
5.0 Cross point
Alveolar Ventilation VAE
0.0
Phase I
0 100 200 300 400
Exhaled Volume Expired Volume (ml)

23. Prognostic Value of Volumetric Capnography Indices in Patients
with ALI/ARDS receiving Mechanical Ventilation
VAE/VT S VAE/VT adm-48h
D
0.7
0,7
ns
Ns
D
S
0.6
0,6
0.5
0,5
VAE/VT 0.83 (0.67-0.93)
0.4
0,4
*
*
* #
0.3
0,3
p<0.05
0.2
0,2
P = 0.013
Adm
adm 244h
2 h 48 h
48h
The best predictor was VAE/VT at admission and after 48h (p = 0.013), with SS of
82% and SP of 64%. The difference between VAE/VT-48h and VAE/VT-adm
( VAE/VT) show SS of 73% and SP of 93% with LR 10.2 and area under ROC
curve of 0.83. Interaction between PaO2/FiO2 and VAE/VT-adm predict survival (p
= 0.003) with an area under ROC curve of 0.84, LR of 2.3, SS 100% and SP 57%.
Physiologic dead space after 48h predicted survival (p = 0.02) with an area under
ROC curve of 0.75, LR of 8.8, SS 63% and SP 93%. Chest 2008

24. TIPS to ventilate Surgical ARDS patients
• Minimize alveolar overdistension
during inspiration:
• Pplat < 28 cmH2O, VT < 8 ml/kg
• Minimize alveolar de-recruitment
during expiration:
• moderate, high PEEP
• Decrease transpulmonary cycling
pressure (difference between Pplat and
PEEP)
• Monitor IAP regularly
• Adjuncts to mechanical ventilation:
RM, prone position, HFOV,….??? but if
yes, do it early and in selected patients