Author Scott Mayer, MD1, Daniel Kissau, MD1, Gregory Schlessinger, MD2 1Department of Medicine, HCA HealthONE, Denver, CO; 2Rocky Mountain Kidney Care, Denver, CO
Case
A 28-year-old female with no past medical history and no home
medications presented to the emergency department with complaints of
chest pain and shortness of breath of two days duration. She vomited
three times and was unable to hold food down. She had previously been in
good health. She denied fevers, chills, cough, wheezing, rhinorrhea,
body aches, or other infectious symptoms. She endorsed recent inhaled
cocaine use and continued nicotine use via vaporizer pen. Her vital
signs were stable on room air, and her physical examination was benign.
Her chest X-Ray and CT of the chest are shown below:
She subsequently had a CT Esophagram that demonstrated no extravasation of contrast.
Question
What is the most appropriate next step in work-up?
A. Direct visualization of the airway B. Surgical washout of the mediastinum C. IV antibiotics D. Esophagogastroduodenoscopy
Answer
A. Direct visualization of the airway
Discussion
The most appropriate next step in the work-up is direct visualization
of the airway with laryngoscopy or bronchoscopy in this patient who
presented with pneumomediastinum in the setting of recreational drug and
vaporizer use.
Air in the mediastinum is visualized on both the chest X-Ray and CT as below:
Our patient is at risk for tracheal perforation from the inhalation
of caustic compounds, including oils from her vaporizer pen and the
inhalation of cocaine. Therefore, evaluation of the patient’s airway via
direct visualization is appropriate to rule out perforation of the
trachea or bronchi.
CT Esophagram effectively rules out an esophageal perforation thereby
negating the need for esophagogastroduodenoscopy (Answer D is
incorrect). Furthermore, she presented with stable vital signs and no
respiratory distress. Whereas if she had signs of sepsis or mediastinal
fat stranding on imaging, acute mediastinitis would be a concern. In
cases of acute mediastinitis, both IV antibiotics and a surgical washout
of the mediastinum are urgently pursued (Answers B & C are
incorrect).
Pneumomediastinum can be classified as spontaneous or secondary.
Spontaneous pneumomediastinum is seen in otherwise healthy subjects
without an obvious causative factor, although predisposing factors
include tobacco and recreational drug use. Secondary pneumomediastinum
can be associated with iatrogenic, traumatic, and non-traumatic causes.
In contrast to secondary pneumomediastinum, spontaneous
pneumomediastinum is a relatively benign process with minimal morbidity
or mortality. According to a metanalysis of 600 patients across 27
papers, there is an approximate 2.9% of associated morbidity with no
reported mortality. However, secondary pneumomediastinum must be
thoroughly ruled out before diagnosing primary pneumomediastinum.
Patients may be observed to ensure stability prior to discharge and
typically have resolution of subcutaneous emphysema within 7-10 days.
While IV antibiotics are sometimes prescribed for these patients while
under observation, they are not necessary given the absence of adverse
outcomes.
Pneumomediastinum can be detected on chest X-ray with a sensitivity
of ~70%-90%, sensitivity approaches 100% on CT scan. If
pneumomediastinum is associated with a pneumothorax, the pneumothorax
will likely justify further hospital stay and intervention.
Our patient presented with multiple risk factors for spontaneous
pneumomediastinum including inhaled drug use, smoking, and vomiting
(which causes an abrupt rise in intrathoracic pressure). The association
between vaporizer use and pneumomediastinum has become more important
to consider as vaporizer use has become more popular.
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