1-year-old castrated male Hound cross 12

Two images of the thorax are provided, RLAT and VD projections.  A large amount of air is present in the peritoneum, outlining the liver lobes, stomach margins, and caudal aspect of the diaphragm.  A focus of alveolar lung pattern is present in most of the accessory lung lobe, partially effacing the margins of the caudal vena cava.  A halo of soft tissue and fat augments the cardiac silhouette on both views.  This cardiac silhouette is continuous caudally with the alveolar lung pattern of the accessory lung lobe.

RADIOGRAPHIC DIAGNOSIS:

1. Large volume pneumoperitoneum.
2. Focal alveolar lung pattern, accessory lung lobe.
3. Mixed fat and soft tissue opacity of the mid-to-caudal mediastinum.

COMMENTS:

If no history of recent surgery, this is a surgical emergency to further determine the cause of the pneumoperitoneum.  Consideration is given to concurrent pneumonia (including inhaled foreign body, unrelated to the pneumoperitoneum).  Mediastinitis perhaps associated with communication of the mediastinum/pericardium and peritoneum could explain the combination of findings.

OUTCOME:

• Skewer through liver & diaphragm into craniodorsal mediastinum
• Retraction of skewer = marked hemorrhage, patient destabilization
  Next day echocardiogram showed thrombus with gas foci in right atrium
• Patient did well & 3 mo later, echo showed minimal residual thrombus and visible sutures in right atrial wall
• 2017 Case 8 PDF