Questions and All Correct Answers
Graded A+.
A potentially fatal syndrome of lung inflammation and injury - Answer Acute Reparatory
Distress Syndrome (ARDS)
ARDS is caused by: - Answer DIRECT injury to lungs or INDIRECTLY by severe illness
Examples of direct injuries that cause ARDS: - Answer Pneumonia/Sepsis**
Gastric aspiration.
Lung contusion.
Fat emboli.
Near Drowning.
Inhalation injury.
Reperfusion: Lung transplant and/or Pulm embolectomy.
Examples of indirect injuries that cause ARDS: - Answer Sepsis**
Severe trauma with shock & DIC.
Cardiopulm. bypass.
Overdose.
Acute pancreatitis.
TRALI.
Burns.
Gastric Aspirations and Near Drowning are examples of which type of lung injury? - Answer
Direct
Sepsis is caused by which type of lung injury? - Answer Can be caused by both direct and
indirect lung injuries.
Severe Trauma, Overdose and Burns are examples of which type of lung injury? - Answer
,~ decreased lung (pulmonary) compliance
~ dyspnea
~*noncardiac* associated *bilateral pulmonary edema*
~ *dense pulmonary infiltrates* on x-ray (ground glass)
Often ARDS occurs in people with no pulmonary disease after what? - Answer an *acute lung
injury*
Despite the different causes of acute lung injury - the trigger for ARDS is a - Answer systemic
inflammatory response
ARDS: The main site of injury in the lung is the - Answer alveolar-capillary membrane
The alveolar capillary membrane is normally permeable to only what? - Answer small
molecules
When injured, the alveolar capillary membrane becomes - Answer damaged and more
permeable to intravascular fluid! The osmotic gradient "shifts" which the allows debris, proteins
& H2O into the alveloi!
The alveolar capillary membrane can be injured during what things? - Answer sepsis - both
direct and indirect.
pulmonary embolism - direct.
shock - indirect.
gastric aspiration - direct.
Burns and inhalation injury - indirect.
The course of ARDS and its management are divided into 3 phases: - Answer 1.
Injury/exudative phase.
2. Reparative/proliferative phase.
3. Fibrotic/chronic phase.
Injury/exudative Phase - Answer Can last up to a week.
, that does not respond to supplemental O2.
Reparative/proliferative phase - Answer Can lasts up to 3 weeks.
Inflammatory response occurs/phase complete when the lung is dense with fibrous tissue.
Increased pulmonary vascular resistance & pulmonary hypertension may occur d/t the
destroyed pulmonary vasculature.
If phase persists widespread fibrosis results.
If arrested lesions resolve and pt. may recover fully.
Fibrotic/chronic phase - Answer Fibrotic tissue replaces normal tissue leading to vascular
occlusion & pulmonary hypertension.
Pulmonary Vessels destroyed.
Decreased lung compliance.
Gas exchange significantly reduced/hypoxemia continues.
Most likely pt. will not survive this stage.
Long term mechanical ventilation and therapy.
What happens to surfactant during ARDS? Why? - Answer Type II pneumocytes, which
produce surfactant, are damaged - therefore surfactant is reduced.
Surfactant is also diluted by the excess fluid that has entered the lungs
What does surfactant do? - Answer Increases lung compliance (elasticity) and prevents
alveolar collapse
As a result of the decreased surfactant activity - what happens to the alveoli? - Answer they
either collapse or they become fluid filled - either way they can no longer function in gas
exchange