Cardiac Tamponade Secondary to Anaphylaxis in a Dog With a Peritoneal-Pericardial Diaphragmatic Hernia

To describe the clinical presentation, management, and outcome of a dog with a peritoneal-pericardial diaphragmatic hernia and cardiac tamponade thought to be secondary to anaphylaxis.

A 10-year-old spayed female Weimaraner presented for an episode of acute collapse. At the time of presentation, the patient was bright, ambulatory (although limping on the left thoracic limb), and had normal perfusion parameters. A stinger was removed from the left thoracic paw pad, and the patient was treated with diphenhydramine. Thoracic and abdominal point-of-care ultrasound identified mild pericardial effusion and gallbladder wall edema. Mild sedation was administered for cardiac assessment, which identified muffled heart sounds and mild pulsus paradoxus. An echocardiogram demonstrated mild cardiac tamponade and the presence of liver lobes surrounded by fluid that appeared contiguous with the pericardial space. An abdominal ultrasound similarly identified a portion of the liver within the pericardium and gallbladder wall edema with no evidence of hepatic venous dilation. The ventral margin of the diaphragm was indistinct on thoracic radiographs. Pericardial effusion resolved within 24 h, and no further clinical signs were seen. At a recheck echocardiogram 1 week later, the patient was doing well at home, and no pericardial effusion or gallbladder wall edema was seen, although a portion of the liver remained within the pericardium.

This report details a previously unreported cause of pericardial effusion.