by prof dr samie alanasary prof of icu ain shams university

1. ARDS
MANAGEMENT
SAMIR EL ANSARY
ICU PROFESSOR
AIN SHAMS
CAIRO

2. Pulmonary
capillary leak
Inactivation of
surfactant
Interstitial
& alveolar edema
Severe & refractory hypoxemia
SHUNTING - Stiff lungs
Alveolar atalectasis
Damage to alveolar capillary
membrane
DIFFUSE lung injury
CAUSES

3. Early pathologic features of ARDS
• Diffuse alveolar damage (DAD)
• There is minimal alveolar septal thickening,
hyperplasia of pneumocytes
• Eosinophilic hyaline membranes present

7. Links Between VILI and MSOF
Biotrauma and Mediator Injuries

8. What does surfactant do?
Alveoli
without
surfactant
Alveoli
with
surfactant

9. Cyanosis
Pao2 / Fio2 < 200
REFRACTORY HYPOXEMIA

10. Gas Extravasation
Barotrauma

11. 1 
A Portal for Gas
& Bacteria?
Microvascular
Fracture in ARDS

12. Excessive PEEP, particularly in combination with
hypovolemia, can decrease cardiac output and
oxygen delivery, and increase the risk of
barotrauma

13. Subcutaneous emphysema

15. CT scan showed Severe surgical emphysema and pneumomediasteum

19. Diseased Lungs Do
Not Fully Collapse,
Despite Tension Pneumothorax
…and
They cannot always
be fully “opened”
Dimensions of a fully
Collapsed Normal Lung

20. Tension Cysts

21. Spectrum of Regional Opening Pressures
(Supine Position)
Superimposed
Pressure Inflated 0
Alveolar Collapse
(Reabsorption) 20-60 cmH2O
Small Airway
Collapse
10-20 cmH2O
Consolidation 
Lung Units at Risk for Tidal
Opening & Closure
=
Opening
Pressure

22. How Much Collapse Depends on the Plateau
R = 100%
20
60
100
Pressure [cmH2O]
20 40 60
TotalLungCapacity[%]
R = 22%
R = 81%
R = 93%
0
0
R = 0%
R = 59%
Some potentially
recruitable units
open only at high
pressure
More Extensive
Collapse But
Lower PPLAT
Less Extensive
Collapse But
Greater PPLAT

23. Mechanical Ventilator

24. PRESSURE VOLUME CURVE

25. Recruitment Maneuvers (RMs)
Proposed for improving
Arterial oxygenation
Enhancing alveolar recruitment
All consisting of short-lasting increases in
intrathoracic pressures

26. Recruitment Maneuvers (RMs)
–Vital capacity maneuver
(inflation of the lungs up to 40 cm H2O,
maintained for 15 - 26 seconds)
–Intermittent sighs
–Extended sighs

27. Recruitment Maneuvers (RMs)
–Intermittent increase of PEEP
–Continuous positive airway pressure
(CPAP)
–Increasing the ventilatory pressures to a
plateau pressure of 50 cm H2O for 1-2
minutes

28. Other manoeuvres
• Prone positioning ventilation
• Prolonged inspiration
• Inverse ratio ventilation

29. Limit of open lung strategy
• To minimise VILI
to the less damaged alveoli
Max insp pressure
(plateau pressure 30-32cm H20)

30. Limit of open lung strategy
Max pressure remains unchanged
TV will decrease
Alveolar ventilation will decrease
Alv V: dead space vent ratio
will decrease

31. Increasing PaCO2
• Management options
Increase resp rate
Minute
volume
Delivered TV TV ml/kg Resp rate
6.4 L 640 ml 8 10
6.4 L 480 ml 6 14
6.4 L 320 ml 4 20
6.4 L 160 ml 2 40
Anatomical dead space 150ml

32. Increasing PaCO2
• Permissive hypercapnia
• Tracheal gas
insuflation
•Reduce
•dead space

33. Increasing PaCO2
As alveolar ventilation decreases
will require increasing FIO2
Otherwise will result
in alveloar hypoxia and arterial
hypoxaemia

34. Liquid
Ventilation
More clinical trials are req. to demonst.
efficacy.

35. • Inert
• No odor
• No color
• Low surface tension
• Carry large amount of O2 & CO2
Perfluorocarbon
(PFC)

36. Medication:
Morphine sulfate
(0.1mg/kg/dose), pavulon
(0.1 mg/kg/dose)
Rimar (30 ml/kg)
Ventilation settings:
Ti 5 sec, hold 10 sec, Te 5
sec (3-6 cycles/min)
CO2 eleminated by
increase tidal volume
O2 managed by change O2
content and FRC

38. ON START OF GAS
VENTILATION
ONE HOUR AFTER
PLV
48 HOUR AFTER PLV 3 WEEKS AFTER PLV
Partial liquid ventilation with perflubron in premature infants with severe
respiratory distress syndrome

39. High-frequency Oscillatory Ventilation
• Active expiration Pressurised circuit

40. High-frequency Ventilation

41. 35cm
H20
90 cm
3-9 hz
0.1-3ml/kg

42. 42
Pressure transmission HFOV
P
T
proximal
trachea
alveoli
Due to the attenuation of the
pressure wave
by the time it reaches the alveolar
region
it is reduced down to .1 - 5 cmH2O

43. BRONCHOTRON
VENTILATOR
CONVENTIONAL
( = LOW FREQUENCY )
VENTILATION UNIT
PULSATION
( = HIGH FREQUENCY )
VENTILATION UNIT

44. However …
Risks of barotrauma and hemodynamic compromise with high frequency
ventilation can approximate those of conventional ventilation

45. KINETIC THERAPY
MEDISCUS AIR CUSHION
BED PULMONAIR
MEDISCUS TRAUMA BED
ROTOREST

47. APPLICATION OF SURFACTANT
CUROSURF - SURVANTA
ALVEOLFACT
50 – 200 mg/kgBW
BY ENDOTRACHEAL OR ENDOBRONCHIAL ROUTE

48. APPLICATION OF SURFACTANT
• PREVENT END-EXPIRATORY COLLAPSE OF
ALVEOLI
• RECRUITMENT OF ATELECTATIC LUNG
AREAS
• IMPROVED COMPLIANCE
• IMPROVED OXYGENATION
• IMPROVED VENTILATION /PERFUSION
RATIO

49. SECRETION ELEMINATION
VIA IPPB
• BETTER DISTRIBUTION OF
MEDICATED AEROSOLS
• BRONCHOSPASMOLYTIC
• IMPROVED OXYGENATION
• SECRETOLYSIS

50. JET THERAPY
• SECRETOLYSIS ( SECRETION MOBILISATION )
• DISSOLUTION OF RESORPTIVE ATELECTASES
• IMPROVED OXYGENATION
• INTRACRANIAL PRESSURE REDUCTION

51. CLINI – JET
HIGH FREQUENCY JET VENTILATION
HFJV
 HANDY INSTRUMENT
 PRODUCES SHORT
GAS PULSES
 FOR SECRETOLYSIS
 DISSOLVE SECRETIONS
( KETCHUP EFFECT )

52. INCENTIVE SPIROMETRY
SUSTAINED MAXIMAL INSPIRATION
• ALVEOLAR RECRUITMENT
• PREVENTION OF ATELECTASES
• MUSCLE TRAINING
• COUGH PROVOCATION
• IMPROVED OXYGENATION AND VENTILATION

53. Dilates pulmonary
blood vessels and
helps reduce
shunting
REDUCTION IN INTRAPULMONARY R-L SHUNT
Nitric Oxide

54. GOOD LUCK
SAMIR EL ANSARY
ICU PROFESSOR
AIN SHAMS
CAIRO
elansarysamir@yahoo.com