Akesh Thomas, MBBS, Department of Internal Medicine, East Tennessee State University, Johnson City, TN
Dennis Peter Jacob, MBBS, Department of Internal Medicine, St. Mary Mercy Livonia Hospital, Livonia, MI
Girendra V Hoskere, MBBS, Department of Pulmonary and Critical Care, East Tennessee State University, Johnson City, TN
Case
A 28-year-old Caucasian male with a history of asthma and
polysubstance abuse came with complaints of shortness of breath and
cough for two weeks, which worsened over the last 24 hours. At the time
of presentation, he was saturating 88-90% on room and 94% with 2 liters
of oxygen. He was able to speak in full sentences and was not using any
accessory muscles of respiration to breathe. Physical exam was
significant for a respiratory rate of 24, bilateral expiratory wheezes,
and palpable crepitus of the left upper chest wall and shoulder regions.
Arterial blood gas showed a pH of 7.44 with PaO 2 of 77 and PaCO 2
of 34. Complete blood count and comprehensive metabolic panel were
within the normal range. The chest X-ray obtained is given below (Image
1). A CT scan obtained is also given below (Image 2).
Image 1Image 2
Question
How would you manage this patient?
A. Immediate Bronchoscopy B. No Treatment Needed C. Inhaled Beta-agonists and Oral/IV steroids D. Intubation and Mechanical Ventilation E. Emergency Barium Esophagogram
Answer
C. Inhaled Beta-agonists and Oral/IV steroids
Discussion
The patient has spontaneous pneumomediastinum (SPM) and associated
sub-cutaneous emphysema, an uncommon complication of asthma exacerbation
[1]. The chest X-ray shows subcutaneous emphysema, mostly in the neck
and upper chest area. The CT image shows areas of visible mediastinal
air [Image 3]. SPM is believed to occur due to rupture of marginal
alveoli from increased intra-alveolar pressure [2]. Over distention of
the alveoli and decreased perivascular interstitial pressure can also be
contributing to the alveolar rupture. Asthma and inhalational drug
abuse are the two common causes of SPM. Other rare causes include
coughing, shouting, strenuous exercise, and scuba diving [3]. Hamman's
sign (crunching noise heard with heartbeat on auscultation) is a classic
finding in pneumomediastinum. A chest x-ray in the appropriate clinical
setting is often diagnostic; typical findings include gas lining
lateral to main pulmonary artery and aorta, continuous left
hemidiaphragm sign, Naclerio's V sign, and ring around the artery sign
[4]. If in doubt, a CT scan of the chest is warranted to exclude any
major viscous perforation. SPM is self-resolving with supportive
management, including oxygen supplementation and treatment of the
underlying cause. Here the appropriate treatment for asthma exacerbation
is needed, which is inhaled beta-agonist and steroid treatment (choice C
is correct, and B is incorrect). Surgical intervention may become
necessary in very rare cases with cardio-respiratory compromise [5], as
in patients with tension pneumomediastinum. It is noteworthy that in
many cases, if the patient is asymptomatic, observation without any
active intervention is adequate.
Bronchoscopy would be an unnecessary and unyielding intervention for
this patient (choice A is incorrect). The severity of the asthma
exacerbation does not require intubation and mechanical ventilation
(choice D is incorrect) but should be treated with inhaled medications
and steroids. Esophagogram can be done in cases of SPM if the suspicion
of esophageal perforation is high. In this case, the concern for
perforation is low with the history provided. If performed, it should be
done with a water-soluble contrast like gastrografin rather than barium
(choice E is incorrect).
Image 3
References
Akinyemi, R., Ogah, O., Akisanya, C., Timeyin, A., Akande, K.,
Durodola, A., Ogundipe, R., & Osinfade, J. (2007). Pneumomediastinum
and subcutaneous emphysema complicating acute exacerbation of bronchial
asthma. Annals of Ibadan postgraduate medicine, 5(2), 78–79.
https://doi.org/10.4314/aipm.v5i2.64035
Mitchell, P., King, T., & O'Shea, D. (2015). Subcutaneous
Emphysema in Acute Asthma: A Cause for Concern?. Respiratory Care,
60(8), e141-e143. doi: 10.4187/respcare.03750
Bejvan, S., & Godwin, J. (1996). Pneumomediastinum: old signs and
new signs. American Journal Of Roentgenology, 166(5), 1041-1048. doi:
10.2214/ajr.166.5.8615238
Unger, D., & Pifarré, R. (1972). Tracheotomy for Subcutaneous
Emphysema and Pneumomediastinum Complicating Asthma. Chest, 61(7),
691-692. doi: 10.1378/chest.61.7.691
