EM@3AM – Acute Chest Syndrome

Author: Erica Simon, DO, MHA (@E_M_Simon, EM Chief Resident, SAUSHEC, USAF) // Edited by: Alex Koyfman, MD (@EMHighAK, EM Attending Physician, UTSW / Parkland Memorial Hospital) and Brit Long, MD (@long_brit, EM Attending Physician, SAUSHEC, USAF)

Welcome to EM@3AM, an emdocs series designed to foster your working knowledge by providing an expedited review of clinical basics. We’ll keep it short, while you keep that EM brain sharp.

 A 4-year old male with a history of sickle cell anemia presents to the ED for evaluation of fever of two days duration (Tmax 103.2) and progressively worsening shortness of breath. The patient’s parents report 48-hour hospitalization 6 months prior secondary to a vaso-occlusive crisis (pain localized to the extremities). ROS is negative for sick contacts. Medications include penicillin prophylaxis. Immunizations are up to date.

VS: HR 127, BP 97/64, RR 32, SpO2 91% on room air.

Physical examination:
Neuro: GCS 15
HEENT: PERRLA, TMs clear bilaterally, nasal mucosa unremarkable, oropharynx clear and moist, no lymphadenopathy
CV: Tachycardia, cap refill 2 secs
Pulm: End-expiratory wheezing
Abdomen: ND, NT, no guarding or rebound
GU: Without findings
MSK: No TTP
Derm: No rashes

CXR demonstrates multi-lobar infiltrate.

What is the patient’s diagnosis? What’s the next step in your evaluation and treatment?

Answer: Acute Chest Syndrome (ACS)^1-3

• Presentation: fever (>38.5°C or 101.3°F), tachypnea, cough, +/-chest pain, +/- wheezing and new infiltrate on CXR
• Evaluation:
  • CXR, CBC, reticulocyte count, VBG, blood cultures, sputum culture²
  • Consider underlying etiologies and evaluate as appropriate:
    • Sepsis
    • PNA
    • PE
    • Fat embolism
•  Treatment:
  • Bronchodilators – improve peak expiratory flow²
  • Incentive spirometry and analgesia – prevent development/worsening of atelectasis
  • Empiric antibiotic therapy following procurement of culture samples (target Chlamydia, Mycoplasma, and Streptococcus)
  • Oxygen therapy to maintain SpO2 >92%
  • Fluid resuscitation targeting euvolemia (avoid iatrogenic pulmonary edema)
  • Exchange transfusion (in consultation with heme/onc) for:
    • Severe hypoxemia
    • Multi-lobar involvement
    • Worsening course
•  Pearls:
  • Acute chest syndrome is the leading cause of death in sickle cell patients in the U.S. (12% mortality).²
  • Infection is most common cause of ACS ( C. Pneumoniae and RSV).
  • A normal pulmonary exam is most frequently associated with ACS.²
  • ACS rapidly progresses to ARDS = admit to ICU level care

References:

1. Tintinalli J, Kelen G, Stapczynski J, Ma O, Cline D, et al. Tintinalli’s Emergency Medicine. 8^th ed. New York: McGraw-Hill; 2016. Chapter 236, Sickle Cell Disease and Hereditary Hemolytic Anemias.
2. Vichinsky E, Neumayr L, Earles A, Williams R, Lennette E, et al. Causes and outcomes of the acute chest syndrome in sickle cell disease. N Engl J Med. 2000; 342:1855-1865.
3. Traill L and Barton M. Focus On: Acute Chest Syndrome – The Critical Cough. American College of Emergency Physicians Clinical and Practice Management. 2008. Available from: https://www.acep.org/Clinical—Practice-Management/Focus-On–Acute-Chest-Syndrome—The-Critical-Cough/