This document discusses acute respiratory distress syndrome (ARDS). ARDS is defined as an acute, diffuse inflammatory lung injury caused by diverse pulmonary and non-pulmonary insults, characterized by increased vascular permeability and loss of aerated lung tissue. The main criteria are hypoxemia, bilateral opacities on chest x-ray, decreased lung compliance, and increased physiological dead space. Management involves treating the underlying cause while providing supportive care such as mechanical ventilation. Outcomes depend on severity but may include long-term pulmonary dysfunction or neurocognitive impairments.

1. ACUTE RESPIRATORY DISTRESS
SYNDROME
ARDS
Mohammed A AlQauyyed
Pediatric Resident R3

2. OBJECTIVES
DEFINITION CRITERIA MANAGEMENT OUTCOMES

3. ARDS DEFINITION
 It is an acute, diffuse, inflammatory lung injury caused by diverse
pulmonary and non-pulmonary etiologies.
 It is characterized by increased vascular permeability, increased lung
weight and loss of aerated tissue within the 7 days of insult.

4. ARDS DEFINITION
 Hypoxemia, bilateral opacities on the chest x-ray, decreased lung
compliance and increased physiological dead space are the main
clinical signs.
 Diffuse alveolar damage characterized by edema, inflammation,
hyaline membrane formation or pulmonary hemorrhage are the
pathological hallmark.

5. ARDS CRITERIA
The Pediatric Acute Lung Injury Consensus Conference Group PALICC
Pediatr Crit Care Med. 2015 Jun; 16(5): 428–4

6. ARDS AT RISK
Pediatr Crit Care Med. 2015 Jun; 16(5): 428–4

7. ARDS EQUATION
Oxygenation Index (OI) = (FiO2 X mean airway pressure X 100)/PaO2
Oxygen Saturation Index (OSI) = FiO2 X mean airway pressure X 100 /
SPO2
The PaO2/FiO2 (P/F) ratio can be calculated using PaO2 in mm of Hg
and FiO2in decimal from 0.21 to 1.0.
Pediatr Crit Care Med. 2015 Jun; 16(5): 428–4

8. ARDS EXAMPLE
For example, a patient receiving mechanical ventilation with a mean
airway pressure of 20 cm H2O, FiO2 of 0.6 has SPO2 of 98% and
PaO2 of 85 mm Hg.
OI = (0.6 X 20 x 100)/85 = 14.11
OSI = (0.6 X 20 x 100)/98 = 12.24
P/F ratio = 85/0.6 = 141.66
This patient has moderate ARDS.
https://emedicine.medscape.com/article/803573-

9. ARDS CAUSES

10. ARDS
PATHOPHYSIOLOGY

11. ARDS PATHOPHYSIOLOGY
 Initial phase: areas of normal lungs are more so PEEP works, Later
(>5-7days) abnormal lung increases so PEEP is less effective,
PaCo2 increases.
 Fibroproliferative phase: slow recovery & ventilator dependency.
 Resolution phase: gradual recovery of hypoxemia, compliance, X
ray resolution

12. ARDS CLINICAL FEATURES
 Dyspnea, agitation, increased WOB
 Hypoxemia refractory to supplemental O2 ➞ Hypercarbia ➞
Acidosis.
 Lung:
scatter of normal alveoli along with various grades of severity of involvement
 Xray:
B/l infiltrates – patchy, asymmetric, may associated with pleural effusion
 In progressive fibrosing alveoli:
persistant hypoxemia, decreasing compliance, Pulmonary HT ➞ Rt ventricular
failure

13. ARDS
CASE
14 month-old boy K/C of
bronchopulmonary
dysplasia.
Chest X-Ray on day of
admission.

14. ARDS
CASE
14 month-old boy K/C of
bronchopulmonary
dysplasia.
Chest X-Ray on 2nd day of
admission in the morning.

15. ARDS
CASE
14 month-old boy K/C of
bronchopulmonary
dysplasia.
Chest X-Ray on 2nd day of
admission afternoon

16. ARDS
CASE
14 month-old boy K/C of
bronchopulmonary
dysplasia.
Chest X-Ray on 3rd day of
admission.

17. ARDS MANAGEMENT

18. ARDS OUTCOMES
 Pulmonary Function
Screening for pulmonary function abnormalities within the first year after
discharge.
Spirometry for older children.
pulmonologist referral.
 Neurocognitive Development
physical, neurocognitive, emotional, family, and social function be evaluated within
3 months

19. RESOURCES