Acute Chest Syndrome

Author: Moises Gallegos, MD MPH
Updated: 1/23/2020

Acute Chest Syndrome

Background [1, 2]

  • A leading cause of hospitalization and mortality in sickle cell patients
  • Up to half of sickle cell patients will develop
  • More common in HbSS but can occur in any phenotype
  • Higher incidence in children but more severe and worse outcomes in adults
  • Definition: fever and/or respiratory symptoms + radiodensity on chest x-ray

Causes

  • Children: Most commonly associated with infection or reactive airway disease

    • Atypical bacteria or Respiratory Syncytial Virus (RSV)
    • Inflammation results in pulmonary vaso-occlusion

  • Adults: Bone marrow/fat emboli

    • Vaso-occlusion in bone marrow leads to release of bone marrow/fat emboli into circulation
    • Mechanical obstruction occurs in small vessels of lungs

Pathophysiology

  • Intra-pulmonary vascular obstruction, as a result of infection or emboli, causes hypoxia, inflammation, and acidosis that further worsen vaso-occlusion.

Management [3-5]

  • Supplemental oxygen and incentive spirometry

    • Consider noninvasive positive-pressure ventilation if unable to maintain oxygen saturation > 92% with nasal cannula or non rebreather mask.

  • IV fluids to avoid hypovolemia

    • D5 1/2 NS (resuscitate to euvolemia)

  • Antibiotics

    • Third generation cephalosporin + macrolide
    • Fluoroquinolone

  • Blood transfusion

    • Exchange transfusion has potential advantage- higher volume of packed Red Blood Cells to lower the Hgb S percentage.
    • Simple transfusion- should be used, regardless of severity, to achieve goal of Hgb > 10 g/dL if anemia present

  • Pain control

    • Caution over-sedation that can worsen respiratory drive

  • Adjuncts

    • Bronchodilators can be considered for patients with reactive airway disease.
    • Glucocorticoids shown to decrease hospital stay, but associated with re-admission

  • Venous thromboembolism prophylaxis

    • All patients with suspected Acute Chest Syndrome should receive prophylaxis of venous thromboembolism unless contraindicated.

Bottom Line

  • Acute Chest Syndrome occurs in both children and adults regardless of sickle cell disease phenotype.
  • Treatment focuses on minimizing vaso-occlusion in pulmonary vasculature: Oxygen, IV fluids, antibiotics, blood transfusion
  • Although pulmonary infection is less common in adults, cover with antibiotics since cannot distinguish from embolic cause in initial phase.

References

  1. Vichinsky EP, Styles LA, Colangelo LH, et al. Acute Chest Syndrome in Sickle Cell Disease: Clinical Presentation and Course. Cooperative Study of Sickle Cell Disease. Blood. Mar, 1997; 89(5):1787-1792.[PubMed]
  2. Lovett PB, Sule HP, Lopez BL. Sickle Cell Disease in the Emergency Department. Hematol Oncol Clin N Am. 2017; 31: 1061-1079. [PubMed]
  3. Simon E, Long B, Koyfman A. Emergency Medicine Management of Sickle Cell Disease Complications: An Evidence-Based Update. J Em Med. 2016; 51(4):370-381. [PubMed]
  4. Porter M. Rapid Fire: Sickle Cell Disease. Emerg Med Clin N Am. 2018; 36: 567-576. [PubMed]
  5. Farooq S, Omar MA, Salzman GA. Acute chest syndrome in sickle cell disease. Hosp Prac. Apr, 2018; 46(3): 144-151. [PubMed]