2. ObjectivesObjectives
1. Recognize the causes of1. Recognize the causes of
pneumomediastinumpneumomediastinum
2. Recognize the presentation2. Recognize the presentation
3. Identify common radiological signs3. Identify common radiological signs
4. Discuss when to order additional tests4. Discuss when to order additional tests
5. Treatment5. Treatment
3. Pulmonary Causes:Pulmonary Causes:
Rupture of the alveolus with air dissectionRupture of the alveolus with air dissection
along the peribronchial vascular sheaths intoalong the peribronchial vascular sheaths into
the hilum and mediastinumthe hilum and mediastinum
Ruptured bleb with peripheral extensionRuptured bleb with peripheral extension
Sudden rise in intrapulmonary pressureSudden rise in intrapulmonary pressure
Asthma, vomiting, forceful coughing, crying,Asthma, vomiting, forceful coughing, crying,
shouting, Valsalva maneuver, artificial ventilation,shouting, Valsalva maneuver, artificial ventilation,
closed chest trauma, sudden drop in atmosphericclosed chest trauma, sudden drop in atmospheric
pressure, foreign body aspirationpressure, foreign body aspiration
4. TraumaTrauma
Rupture of trachea or mainstemRupture of trachea or mainstem
bronchus, usually via accidental traumabronchus, usually via accidental trauma
Trauma to the neckTrauma to the neck
Boerhaave’s SyndromeBoerhaave’s Syndrome
BarotraumaBarotrauma
5. MediastinumMediastinum
ConnectionsConnections
The mediastinum communicates with theThe mediastinum communicates with the
submandibular space, retropharyngealsubmandibular space, retropharyngeal
space and vascular sheaths within thespace and vascular sheaths within the
neckneck
Also can communicate with theAlso can communicate with the
retroperitoneum via sternocostalretroperitoneum via sternocostal
attachments to the diaphragm, as well asattachments to the diaphragm, as well as
the periaortic and periesophageal fascialthe periaortic and periesophageal fascial
planesplanes
6. PresentationPresentation
Infants-typically noneInfants-typically none
Adults-Adults-
May complain of retrosternal chest pain radiatingMay complain of retrosternal chest pain radiating
down both arms that is exacerbated by respirationdown both arms that is exacerbated by respiration
and swallowingand swallowing
Dyspnea-in association with asthma, tension PM orDyspnea-in association with asthma, tension PM or
pneumothoraxpneumothorax
Fever-due to cytokine release with an air leakFever-due to cytokine release with an air leak
Throat or jaw pain, dysphonia, dysphagia, neckThroat or jaw pain, dysphonia, dysphagia, neck
swelling and torticollisswelling and torticollis
7. Physical ExamPhysical Exam
Subcutaneous AirSubcutaneous Air
Associated PneumothoraxAssociated Pneumothorax
Oxygen SaturationsOxygen Saturations
Hamman’s Sign-Hamman’s Sign-
““Crunching” sound heard over the apex ofCrunching” sound heard over the apex of
the heart with the cardiac cyclethe heart with the cardiac cycle
9. Extrapleural SignExtrapleural Sign
Air from theAir from the
mediastinum canmediastinum can
extend laterallyextend laterally
between the parietalbetween the parietal
pleura and thepleura and the
diaphragm todiaphragm to
produce theproduce the
extrapleural signextrapleural sign
10. Double Bronchial SignDouble Bronchial Sign
Air in theAir in the
mediastinum and leftmediastinum and left
main bronchusmain bronchus
allows visualizationallows visualization
of both sides of theof both sides of the
bronchial wall.bronchial wall.
11. Spinnaker SignSpinnaker Sign
(Thymic Sail Sign)(Thymic Sail Sign)
With sufficient
mediastinal air, the
thymus can
become elevated,
creating the
Thymic Sail Sign,
or Spinnaker Sign.
18. Diagnostic ProceduresDiagnostic Procedures
Chest tube in coexisting pneumothoraxChest tube in coexisting pneumothorax
Bronchoscopy if tracheobronchialBronchoscopy if tracheobronchial
perforation is suspectedperforation is suspected
Esophagoscopy if an esophagealEsophagoscopy if an esophageal
perforation is suspectedperforation is suspected
19. TreatmentTreatment
Mechanical ventilation with low pressureMechanical ventilation with low pressure
or tidal volumesor tidal volumes
Mediastinoscopy to alleviate life-Mediastinoscopy to alleviate life-
threatening pneumomediastinumthreatening pneumomediastinum
Percutaneous placement of mediastinalPercutaneous placement of mediastinal
drainsdrains