Updated: 5/27/2021

Adult Respiratory Distress Syndrome

0%
Topic
Review Topic
0
0
N/A
N/A
Questions
1
0
0
100%
0%
Evidence
2
0
0
Topic
Images
https://upload.orthobullets.com/topic/1006/images/ards.jpg
  • Summary
    • Adult respiratory distress syndrome (ARDS) is a pulmonary condition that can arise after polytrauma and long bone fractures leading to acute lung injury and progressive respiratory distress, refractory hypoxemia and pulmonary edema.
    • Diagnosis is made in the polytrauma patient by calculation of hypoxemia defined by PaO2 / FIO2 ratio < 200 mm Hg with chest x-ray revealing diffuse bilateral pulmonary infiltrates with pulmonary edema.
    • Treatment is focused on prevention with early stabilization of long bone fractures and PEEP ventilation when ARDS develops.
  • Etiology
    • Pathophysiology
      • acute endothelial damage resulting from
        • aspiration
        • infection
        • pancreatitis
        • multiple blood transfusions
        • lung injury
        • sepsis or shock
        • major trauma
        • large surface area burns
        • fat emboli
        • thromboembolism
        • multi-system organ failure
      • pathoanatomy
        • injury cascade leads to
          • non-cardiogenic pulmonary edema
          • respiratory distress
          • refractory hypoxemia
          • decreased lung compliance
  • Classification
    • ARDS is represented by three phases
    • 3 phases of ARDS
      Exudative phase

      Initially

      Hyaline membrane comprised of fibrin form
      Proliferative phase

      3 days

      Alveolar exudate resolves or organizes
      Fibrotic phase

      3-4 weeks

      Alveolar ducts and spaces undergo fibrosis
  • Presentation
    • Symptoms
      • acute onset (12-48 hours) of
        • dyspnea
        • fever
        • mottled or cyanotic skin
    • Physical exam
      • resistant hypoxia
      • intercostal retractions
      • rales/crackles and ronchi
      • tachypnea
  • Evaluation
    • Hypoxemia is refractory to O2
      • 3 different categories of ARDS based on degree of hypoxemia
      • PaO2 / FIO2 ratio < 300 mm Hg= mild
        • classified as acute lung injury (ALI)
      • PaO2 / FIO2 ratio < 200 mm Hg= moderate
        • values below 200 classified as ARDS
      • PaO2 / FIO2 ratio < 100 mm Hg= severe
    • Chest xray
      • shows patchy pulmonary edema (air space disease)
      • diffuse bilateral pulmonary infiltrates
        • normal sized heart
          • makes CHF less likely
    • Respiratory compliance (<40 mL/cm H20)
    • Positive end-expiratory pressure (>10cm H20)
    • Corrected expired volume per minute (>10L/min)
  • Differential
    • Cardiogenic pulmonary edema (i.e. CHF or MI), bilateral pneumonia, SARS
  • Treatment
    • Nonoperative
      • PEEP ventilation and steroids
      • treat the underlying pathology/disease
    • Operative
      • early stabilization of long bone fractures (femur)
    • Prevention
      • closely monitor PEEP in patients at-risk of ARDS
      • serial X-rays in concerning patients can assist in early identification and intervention
  • Complications
    • Pneumothorax
      • secondary to ventilator with high PEEP
  • Prognosis
    • High mortality rate (50% overall) is associated with ARDS even in setting of ICU

Please rate this review topic.

You have never rated this topic.

Thank you. You can rate this topic again in 12 months.

Flashcards (0)
Cards
1 of 0
Questions (1)
Question locked
Sorry, this question is for
PEAK Premium Subscribers only
Upgrade to PEAK
Evidence (2)
EXPERT COMMENTS (8)
Private Note