Spontaneous pneumomediastinum without pneumothorax in ...

THE NEW ZEALAND
MEDICAL JOURNAL
Journal of the New Zealand Medical Association
Spontaneous pneumomediastinum without pneumothorax in
idiopathic pulmonary fibrosis
Martyn P T Kennedy, Ahmed Fahim, Graham Smith
A 58-year-old man with a background of idiopathic pulmonary fibrosis (IPF)
presented with a sudden onset of breathlessness following repeated coughing. He was
a life-long non-smoker. On examination, there was evidence of extensive
subcutaneous emphysema involving his neck and chest. He was haemodynamically
stable with oxygen saturations of 95% breathing room air.
A chest radiograph, obtained at presentation, showed evidence of
pneumomediastinum (Figure 1) as well as presence of subcutaneous air in a diffuse
pattern.
Figure 1. Chest radiograph showing evidence of subcutaneous emphysema and
pneumomediastinum
A thoracic computed tomography (CT) scan (Figure 2) was obtained to further
characterise the extent of pneumomediastinum and evaluate for co-existing
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pneumothorax. The CT scan confirmed the radiographic findings of mediastinal air
collection with no evidence of either a pneumothorax or oesophageal rupture.
Figure 2. Images from a CT scan showing subcutaneous emphysema and
pneumomediastinum without any co-existing pneumothorax
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The patient was treated conservatively with spontaneous improvement in symptoms
and significant resolution of pneumomediastinum on follow-up chest radiographs.
This case highlights the importance of considering spontaneous pneumomediastinum
(SPM) following repeated attacks of cough in a patient with IPF. Although
pneumothorax is commonly associated with SPM, this case suggests that this
diagnosis should be considered even in the absence of a pneumothorax. The likely
mechanism of the development of SPM is alveolar rupture secondary to increased
intrathoracic pressure. 1,2
In this particular case, the increased intrathoracic pressure is believed to be the result
of extensive cough. CT scan is the diagnostic modality of choice in suspected SPM as
it provides more precise information regarding the presence, extent of extra-alveolar
air and co-existing pneumothorax. 3
Author information: Martyn PT Kennedy, SHO; Ahmed Fahim, SpR; Graham
Smith, Consultant; Respiratory Medicine, Pinderfields Hospital, Mid Yorkshire NHS
Trust, Wakefield, England
Correspondence: Dr Martyn Kennedy, c/o Dr G Smith, Pinderfields Hospital,
Aberford Road, Wakefield WF1 4DG, UK. Email: martynkennedy@doctors.org.uk
References:
1. Macklin CC. Transport of air along sheats of pulmonic blood vessels from alveoli to
mediastinum. Arch Intern Med. 1939;64:913-926.
2. Abolnik I, Lossos IS, Breuer R. Spontaneous pneumomediastinum. A report of 25 cases.
Chest. 1991;100:93-95.
3. Franquet T, Giménez A, Torrubia S, et al. Spontaneous pneumothorax and
pneumomediastinum in IPF. Eur Radiol. 2000;10:108-13.
NZMJ 20 January 2012, Vol 125 No 1348; ISSN 1175 8716 Page 102
http://journal.nzma.org.nz/journal/125-1348/5028/ ©NZMA