ARDS

Question 1

Define ARDs

Answer 1

Life-threatening lung condition that prevents enough oxygen from getting to the lungs and into the blood

Question 2

What general class of pulmonary dysfunction does ARD fall under?

Answer 2

Form of pulmonary edema that can quickly lead to acute respiratory failure

Question 3

What can ARDs follow?

Answer 3

May follow direct or indirect injury to lungs

Question 4

What can happen if ARDs isn’t promptly diagnosed and treated?

Answer 4

Death can occur within 48 hours of onset if ARDS isn’t promptly diagnosed and treated

Question 5

What is the number 1 cause of Ards? What are number 2 and 3?

Answer 5

1. Sepsis
# 1 cause
2. Severe multiple trauma
A. Fat emboli
B. Pulmonary contusion
3. Aspiration pneumonia (gastric contents)

Question 6

What percentage of ARDs cases are due to the top 3 causes?

Answer 6

75%

Question 7

What are the less common causes of ARDs?

Answer 7

1. Shock
2. Toxic inhalation
   A. Ammonia
   B. Chlorine
3. Near drowning
4. Multiple transfusions

Question 8

What is the pathophys of ARDs?

Answer 8

Injury involves both pulmonary capillary epithelium and alveolar epithelium

Question 9

What is direct damage that can cause ARDs?

Answer 9

Direct – aspiration of gastric contents or noxious fumes

Question 10

What is the indirect damage that can cause ARDs?

Answer 10

Indirect – chemical mediators released in response to systemic disease

Question 11

How does pulmonary edema develop in ARDs?

Answer 11

↑ permeability of alveolar capillary membrane which leads to development of protein rich pulmonary edema

Question 12

What is the cascade of biochemical and cellular changes seen in ARDs?

Answer 12

1. Injury reduces normal blood flow to lungs
2. Platelets aggregate & release histamine, serotonin, and bradykinins
3. → inflame & damage alveolar capillary membrane
4. ↑ capillary permeability
5. Proteins & fluid leak out  increasing interstitial osmotic pressure  pulmonary edema
6. Fluid in alveoli  alveoli collapse
7. ↓ gas exchange

Question 13

What are the symptoms of ARDs?

Answer 13

1. Restlessness, apprehension, mental sluggishness

2. Frothy pink sputum

Question 14

What are the signs of ARDs?

Answer 14

Tachypnea
Shallow breathing
Diffuse rales

Question 15

What are the CXR results seen in ARDs?

Answer 15

1. May be normal in early stages, w/ ↑ abnormal findings as progresses
   A. Peripheral infiltrates, sparing costophrenic angles
   B. Air bronchograms in 80% patients
   -Air-filled bronchi (dark) being made visible by the opacification of surrounding alveoli
2. In later stages, lung fields with “white outs” of both lung fields

Question 16

What are the initial results of ABG dx studies in ARDs?

Answer 16

1. Dec pO2 (< 60 mm Hg)
2. Decreased pCO2 (< 35 mm Hg)
3. pH = ↑ (respiratory alkalosis)

Question 17

What are the results of ABG dx studies in ARDs if the pt is septic?

Answer 17

Metabolic acidosis → +/- resp compensation

Question 18

What is the hallmark of ARDs?

Answer 18

Hypoxemia despite increased supplemental oxygen

Question 19

What are the later stage results of ABG dx studies in ARDs?

Answer 19

1. As ARDS worsens:
A. ↑ pCO2 (> 45 mmHg)
B. → resp acidosis
C. ↓ HCO3 level (< 22 meq/l)
D. ↓ pO2
-Despite oxygen therapy

Question 20

What test results indicate multi-organ failure?

Answer 20

A. ↑ BUN/Cr
B. ↑ LFT’s
C. ↑ coagulation parameters

Question 21

What is the supportive care treatment for ARDs?

Answer 21

1. Supportive care for severe resp dysfunction
   A. Oxygen via ET intubation with positive pressure ventilation
   B. Hypoxia often resistant to oxygen

Question 22

What is the treatment for ARDs?

Answer 22

1. Antibiotics
2. Respiratory support: ventilator
3. Diuretics
4. Situate patient in semi-prone position

Question 23

What is the prognosis for ARDs?

Answer 23

1. High mortality rate
2. 33% of deaths occur within 3 days of onset of sx’s
3. Remaining deaths occur within 2 weeks of Dx
   A. Caused by multi-organ failure or infection