Category II - ARDS

Question 1

It is a clinical syndrome of severe dyspnea of rapid onset, hypoxemia, and diffuse pulmonary infiltrates leading to respiratory failure.

Answer 1

ARDS

Question 2

According to BERLIN classification, ARDS happens within 2 weeks of a known clinical insult with new/worsening respiratory symptoms. TRUE or FALSE?

Answer 2

FALSE. It happens within 1 week.

Question 3

Chest Xray findings of patients with ARDS

Answer 3

Bilateral alveolar or interstitial infiltrates/opacities

Question 4

Give at least 5 causes of ARDS

Answer 4

Direct lung injury:
Pneumonia
Aspiration of gastric contents
Pulmonary contusion
Near drowning
Toxic inhalation injury

Indirect lung injury:
Sepsis
Severe trauma: multiple bone fractures, flail chest, head trauma, burns
Multiple transfusions
Drug overdose
Pancreatitis
Postcardiopulmonary bypass

Question 5

Phase of ARDS where there is accumulation of edema fluid rich in protein in the interstitial and alveolar spaces

Answer 5

Exudative phase - 1st 7 days after exposure to precipitating risk factor

In exudative phase, neutrophils predominate.
There is injury of alveolar capillary endothelial cells and type I pneumoncytes with loss of the normally tight alveolar barrier to fluid and macromolecules.

Question 6

In proliferative phase of ARDS, what cells predominate?

Answer 6

Lymphocytes

Question 7

There is proliferation of type ___ pneumocytes along alveolar basement membranes to synthesize new pulmonary surfactant in PROLIFERATIVE phase of ARDS.

Answer 7

Type II pneumocytes.

In exudative phase - proliferation of Type I pneumocytes (alveolar epithelial cells)

BUT, among patients who fail to improve, proliferative phase involves progressive lung injury, early changes of pulmonary fibrosis, with presence of alveolar type III procollagen peptide (marker of pulmonary fibrosis): associated with a protracted clinical course and increased mortality in ARDS.

Question 8

ARDS principally involves ___________ portions of the lung with relative sparing of other regions.
A. Upper (apex)
C. Middle
C. Lower (dependent)

Answer 8

Dependent portions

Differing compliance leads to overdistension and injury to the more “normal” areas of the lung during attempts to fully inflate the consolidated lung

Question 9

Strategy to reduce risk of ventilator associated injury among pxs with ARDS?
A. High tidal volume ventilation
B. Low tidal volume ventilation

Answer 9

C. Low tidal volume ventilation –> strong clinical evidence

Question 10

PEEP level of _______ mmHg in ARDS is optimal for alveolar recruitment and is used to minimize FIO2 and optimize PaO2.

Answer 10

12-15 mmHg

Question 11

TRUE or FALSE.

Supine position improves arterial oxygenation but with uncertain effect on survival among pxs with ARDS.

Answer 11

FALSE –> PRONE position

Question 12

Lower left atrial filling pressures are associated with a lower mortality in both medical and surgical ICU patients with ARDS. How will you achieve this?

Answer 12

Fluid restriction and diuretics. But this is limited only by hypotension and hypoperfusion of critical organs such as the kidneys.

Question 13

Alternative therapies for ARDS aside from use of low tidal vlume ventilation?

Answer 13

High PEEP
"Open lung"
Prone position
Recruitment maneuvers
ECMO

Question 14

Mortality estimates in ARDS

Answer 14

26-44%

Mortality largely attributable to nonpulmonary causes: sepsis and nonpulmonary organ failure (>80% of deaths)