DSA ARDS

Question 1

ARDS Diagnosis

Answer 1

Question 2

What is important in the dx of ARDS from other respiratory problems?

Answer 2

Identification of an underlying cause or inciting event is important in differentiating ARDS from other lung diseases or syndromes that may be misidentified as ARDS

Question 3

What are the most common causes of ARDS?

Answer 3

Pulmonary and non Pulmonary sepsis

Question 4

What are the presenting ARDS sx? Progress to what?

Answer 4

1. dyspnea, cough, SOB
2. altered mentaiton, hypercapnia, tachypnea

*leukocytosis is nonspecific, but can suggest underlining cause is an infection

Question 5

What do we see on CXR in ARDS?

Answer 5

• b/l, diffuse airspace infiltrates
• patchy infiltrates become more confluent as the syndrome evolves

Question 6

Answer 6

Question 7

Which cells are injured in ARDS? When?

Answer 7

1. Type I pneumoncyte injury - accounts for early disease due to disruption of barrier integrity; accounts for movement of fluid out of capillary compartment (=pulmonary edema)
2. Type II pneumoncyte injury - leads to impaired surfactant function that contributes to the atelectasis and worsening pulmonary compliance

Question 8

Increases in pulmonary artery pressures secondary to ______, decreases in pulmonary circulation _____, and direct damage to the vascular endothelium lead to _______. Together, each of these contributes to increased ______.

Answer 8

Increases in pulmonary artery pressures secondary to hypoxemic pulmonary vasoconstriction, decreases in pulmonary circulation due to microthrombi, and direct damage to the vascular endothelium lead to worsening dead space ventilation. Together, each of these contributes to increased work of breathing

Question 9

What are the stages of ARDS?

Answer 9

1. Exudative
2. Proliferative
3. Fibrotic OR Resolution

Question 10

What happens in the proliferative stage?

Answer 10

• Type II pneumocytes begin to regenerate in order to reconstitute the surfactant layer
• Type I cells rebuild the damaged alveolar epithelium
• can lead to healing very quickly

Question 11

As vascular changes in the exudative phase become more irreversible, the risk of what increases?

Answer 11

Pulmonary HTN

Question 12

What do you need to dx ARDS?

Answer 12

• b/l infiltrates
• Hypoxemia (PaO2/FiO2 =200
• abrupt onset of sx
• noncardiac in nature

*helfpul to have DADs, but not required for clinical dx

Question 13

What is ventilator induced injury?

Answer 13

The abnormalities in surfactant physiology characterizing ARDS lead to excessive closure of some alveoli during expiration. Repeated closure and over distention leads to additional alveolar damage

Question 14

How does mechanical ventilation improve ARDS?

Answer 14

• allows decreased work of breathing by off-loading respiratory muscles and improving effective minute ventilation
• as the work of breathing decreases, CO2 production is decreased and overall acid-base status is improved.

Question 15

What is a danger to using mechanical ventilation? What is a possible solution?

Answer 15

1. Atelectatic segments, especially those in an area of transition near normal lung, are especially susceptible to overstretching during the inspiratory phase of respiration. The abnormalities in surfactant physiology characterizing ARDS lead to excessive closure of some alveoli during expiration.
2. Lower tidal volumes

Question 16

What is HFOV?

Answer 16

• High frequency oscillatory ventilation
• provides low tidal volumes with increases RR
• decreases risk of over distention

Question 17

Conservative fluid management reduces what?

Answer 17

the number of days spent on a ventilator and in the ICU in ARDS pts without causing nonpulmonary organ dysfunction

Question 18

Benefits of Extracorporeal membrane oxygenation (ECMO)

Answer 18

Extracorporeal membrane oxygenation (ECMO) has the advantage of supporting hypoxemia without the potentially injurious ventilator settings sometimes needed in severe ARDS. Extracorporeal membrane oxygenation (ECMO) has the advantage of supporting hypoxemia without the potentially injurious ventilator settings sometimes needed in severe ARDS. Some of the positive results may reflect that centers comfortable with ECMO may also be expert in general ARDS management.Extracorporeal membrane oxygenation (ECMO) has the advantage of supporting hypoxemia without the potentially injurious ventilator settings sometimes needed in severe ARDS. Some of the positive results may reflect that centers comfortable with ECMO may also be expert in general ARDS management.Extracorporeal membrane oxygenation (ECMO) has the advantage of supporting hypoxemia without the potentially injurious ventilator settings sometimes needed in severe ARDS. Some of the positive results may reflect that centers comfortable with ECMO may also be expert in general ARDS management.

Question 19

What must always be addressed in ARDS patients?

Answer 19

underlying cause

Question 20

Prophylaxis must be taken to avoid what comorbidities in ARDS pts

Answer 20

• DVTs
• bleeding
• stress ulcers
• raise bed to 30 degrees to avoid ventilator associated pneumonia

*perform daily screenings to see if they are able to be removed from the ventilator along with daily interruption of all sedative and analgesic infusions

Question 21

What is the #1 predictor of outcome in ARDS?

Answer 21

• Hypoxemia
• others include: age, no decreased O2 by day 7, length of stay, net positive volume stasus, sepsis

Question 22

A review of 1-year ARDS survivors found that none of the patients were requiring oxygen supplementation and their lung function testing, with the exception of ________ had returned to normal. Most frequently patients experienced functional limitation caused primarily by ________. ________ administration and prolonged duration of _______ are associated with more functional sequelae in these ARDS survivors

Answer 22

A review of 1-year ARDS survivors found that none of the patients were requiring oxygen supplementation and their lung function testing, with the exception of low diffusion capacity, had returned to normal. Most frequently patients experienced functional limitation caused primarily by muscle weakness and fatigue. Corticosteroid administration and prolonged duration of respiratory failure are associated with more functional sequelae in these ARDS survivors