Congenital diaphragmatic hernias in small animals typically consist of an abnormal communication between the peritoneal and pericardial cavities. While diagnosis and treatment of a peritoneal-pericardial diaphragmatic hernia (ppdh) can be relatively straight forward, the exact mechanism behind the formation of this abnormality is not clearly understood. Occasionally complications arise with correction of these hernias. This paper follows the diagnosis and treatment of a case with a ppdh at the Cornell University Hospital for Animals. Anesthetic and post-surgical complications are discussed as well as potential embryological mechanisms behind the formation of congenital hernias.