Pulmonary Edema and Acute Lung Injury Flashcards
Refers to collection of exudate (fluid) in the alveolar spaces
pulmonary edema
What are the causes of pulmonary edema?
- hemodynamic imbalance
- direct alveolar injury
What are the components of hemodynamic imbalance?
- increased hydrostatic pressure
- decreased oncotic pressure
- lymphatic obstruction (rare)
What are the components of direct alveolar injury?
- infectious, chemical, thermal, immune injury
- other (altitude, neurogenic)
What does increase hydrostatic pressure cause in pulmonary capillaries?
Increased pulmonary capillary pressure causing “plasma” transudate to form in alveoli
Is edema independent or dependent?
dependent - settles with gravity
What are the causes of increased hydrostatic pressure?
- left HF
- volume overload
- pulmonary hypertension
What are the causes of decreased oncotic pressure?
- Hypoalbuminemia
- Nephrotic syndrome
- Liver failure
- Protein losing enteropathies (malabsorption)
- Malnutrition
What results when there is injury to alveolar septal tissues?
results in leakage of fluid from blood into alveolar spaces
What are some examples of direct alveolar injury?
- inhaled gases
- liquid aspiration
- drug and chemicals
- shock, sepsis, trauma
- radiation
- transfusion mismatch
What does ARDS stand for?
acute respiratory distress syndrome
ARDS is a clinical syndrome resulting from what?
resulting from diffuse alveolar capillary damage
ARDS is characterized by rapid onset of what?
- severe respiratory insufficiency
- cyanosis
- hypoxemia
What is ARDS resistant to?
resistant to oxygen therapy
What is ARDS resistant to oxygen therapy?
due to loss of gas exchange surface as alveoli are filled with fluid
What are causes of ARDS?
- direct injury
- systemic disorders
What is the main pathological feature of ARDS?
diffuse alveolar damage
What does endothelial injury result in?
increased permeability
In ARDS, what collects in alveoli?
protein-rich exudate
In ARDS, what are attracted and activated?
neutrophils
In ARDS, what contribute to tissue injury and signs/symptoms?
- cytokines
- phagocyte-release digestive enzymes
- oxygen radicals
What is recovery from ARDS usually associated with to some degree?
Recovery usually associated with some degree of pulmonary fibrosis
What kind of onset is ARDS?
progressive
What does ARDS present with?
acute respiratory distress
In ARDS, what is often resistant to respiratory support?
hypoxemia
In ARDS, what is present on chest xray?
bilateral infiltrates
What can pulmonary HTN progress to?
right HF
In ARDS, how long does resolution occur over?
6-12 months
In ARDS, what is the overall mortality?
approx 40%
