A 15-year old male presents to the E.D. with a one 
hour history of pain in his chest and back occurring 
after lifting his mother.  He describes the pain as 
knife-like and non radiating.  His pain worsens with 
deep inspiration.  His pain is currently less severe than 
at onset.  He has a past history of chest pain episodes, 
usually at night while sleeping in bed.
     Exam VS T37 (tympanic), P76, R24, BP 131/65.  
Oxygen saturation 100% in room air.  He is alert and 
active in no distress.  He is tall and thin.  Heart regular, 
no murmurs.  Lungs clear, but diminished breath 
sounds bilaterally.  Abdomen benign.  Peripheral pulses 
are full.  Color and perfusion are good.  Hands 
significant for long thin fingers (arachnodactyly).
     A chest radiograph is ordered.

View CXR.

     This CXR shows a long thorax with hyperexpanded 
lungs.  The aortic shadow is not obviously widened.  
The cardiac silhouette is not enlarged. There is no 
obvious pneumothorax, pneumomediastinum, or 
subcutaneous emphysema.
     Aortic dissection is suspected because of his 
Marfanoid appearance.  A CT scan of the chest and 
aorta is ordered.

View CT scan.

     The CT scan demonstrates a small left-sided 
pneumothorax.  The arrows point to the visceral pleura 
of the lung.  An air space is evident within the pleural 
space.  The aorta is normal.
     Upon closer inspection of subsequent CXR's, the 
pneumothorax is visible as a thin rim of air over the 
apex of the left lung.  It is more obvious on erect and 
expiratory views.  Pneumothoraces may be difficult to 
see on a supine or a partially supine film.  The patient 
should be upright or in the lateral decubitus position to 
see it best.

View close-up of left apex and expiratory view.

     After reviewing the previous case of aortic 
dissection, chest pain in a tall slender patient 
suggesting Marfan's Syndrome, is highly suggestive of 
another aortic dissection.  Marfan's Syndrome is a 
connective tissue disorder prone to aortic dissection.  
Patients with Marfan's Syndrome classically have a 
body stature similar to that of Abraham Lincoln.  
Although such tall slender individuals with chest pain 
raise the possibility of aortic dissection, such individuals 
are also at a higher risk of a spontaneous 
pneumothorax.  Other activities associated with an 
increased risk of air leaks include coughing, valsalva 
maneuvers (eg., musical instrument playing and 
carrying one's mother), substance abuse, positive 
pressure devices, etc.  Patients with chronic lung 
disease such as bronchopulmonary dysplasia, cystic 
fibrosis, bronchiectasis, metastatic disease, etc., are at 
greater risk for a spontaneous pneumothorax.
     Patients with a spontaneous pneumothorax may 
present with chest pain or symptoms of respiratory 
difficulty.  The chest pain may be similar to that of chest 
wall pain in that the pain is usually worse when taking in 
a deep breath.  Crepitance may be palpable if air is 
dissecting into the soft tissues of the neck or the chest 
wall.  Diminished breath sounds may be noticeable if 
the pneumothorax is large enough.  Small 
pneumothoraces may not be detectable by auscultation.
     An immediate chest tube is indicated only if the 
patient is in severe distress.  Otherwise, it may be best 
to obtain a chest radiograph to establish a diagnosis 
before performing an invasive procedure.  This 
pneumothorax was difficult to see on this recumbent 
CXR view.  If a pneumothorax is still suspected, an 
expiratory erect view would accentuate the radiographic 
findings, making it easier to identify a small 
pneumothorax.  As demonstrated in this case, CT scan 
is very sensitive at identifying a pneumothorax, but it is 
usually not necessary since pneumothoraces can 
usually be identified on plain radiographs.
     If the pneumothorax is small and the patient is doing 
well, it is usually not necessary to evacuate it with a 
thoracentesis or a tube thoracostomy.  If no 
deterioration is noted during an observation period in 
the emergency department (that meets with the comfort 
level of the physician and family), it may not be 
necessary to hospitalize the patient (especially with 
teenagers) with a small pneumothorax, if follow-up is 
reliable and the family lives near a medical facility.  
Elective consultation with a surgeon may be beneficial if 
a tube thoracostomy is anticipated.

References
     Templeton JM.  Thoracic Emergencies.  In:  Fleisher 
GR, Ludwig S (eds).  Textbook of Pediatric Emergency 
Medicine, third edition.  Baltimore, MD, Williams and 
Wilkins, 1993, pp. 1348-1349.