ULTRASONOGRAPHIC FINDINGS IN DOGS AND CATS WITH GASTROINTESTINAL PERFORATION S0REN R. BOYSEN, DVM, AMY zyxwvut S. TIDWELL, DVM, DOMINIQUE G. PENNINCK, DVM, DVSC A retrospective study was performed to evaluate the sonographic features of gastrointestinal (GI) perforation in dogs and cats. Sonographic findings in 19 animals (14 dogs and 5 cats) included regional bright mesenteric fat (19), peritoneal effusion (16), fluid-filled stomach or intestines (12), GI wall thickening (11), presence of free air (9), loss of GI wall layering (9), regional lymphadenopathy (S), reduced GI motility zyxwvuts (7), pancreatic changes (4), corrugated intestines (4), presence of a mass (3), presence of a foreign body (3), and mineralization of the gastric wall (1). In 14 patients, “perforation” was listed as a differential diagnosis by the sonographer. Abdominal radiographs and radiographic reports were available for 14 patients. Radiographic findings were decreased serosal detail (12), free air (S), peritoneal contrast medium (l), and suspected foreign body (1). GI perforation was listed as radiographic diagnosis in eight patients, seven of which had evidence of pneumoperitoneum, and one had leakage of contrast material on an upper GI study. In 9/14 patients with radiography, “GI perfo- ration” was listed as a sonographic diagnosis. In three patients in which free air was diagnosed sonographically, radiographs were either not available (2) or the presence of free air was not detected at presentation (1). Peritoneal fluid analysis was performed in nine patients, five of which were iden- tified as septic inflammation, and the remaining four were classified as neutrophilic inflammation with no etiologic agent identified. The histologic or surgical diagnoses were as follows: three intestinal surgical dehiscence; one percutaneous endoscopic gastrostomy tube site leakage; one duodenal adeno- carcinoma; one ileocolic lymphoma; one trichobezoar; one ascarid impaction; and one bobby pin foreign body. In the remaining 10 patients, a focal area of gastridintestinal ulceration or transmurai necrosis with perforation was identified without evidence of an underlying cause. zyxwv Veterinary Radiology zyx & Ultrasound, Vol. 44, No. zyxwvutsr 5, 2003, zyxwvutsr pp 556-564. Key words: cat, dog, gastrointestinal perforation, pneumoperitoneum, radiography, ultrasonography. Introduction ASTROINTESTINAL (GI) PERFORATION is a common cause G of septic peritonitis and can be a life-threatening emer- gency, requiring aggressive treatment. In dogs, the most common cause of GI perforation is dehiscence following the removal of a foreign body. Other causes of GI perforation in animals or humans include gastric dilatation and volvu- lus, GI ulcers, GI neoplasia, blunt abdominal trauma, pen- etrating abdominal trauma, intestinal intussusception, intes- tinal infarction, and iatrogenic causes. 133-6 The clinical his- tory may vary with the inciting cause of the perforation but often includes lethargy, anorexia, vomiting, diarrhea, and dietary indiscretion. The clinical and laboratory signs asso- From the Sections of Emergency and Critical Care (Boysen) and Radi- ology (Tidwell and Penninck), Department of Clinical Sciences, Tufts University School of Veterinary Medicine, North Grafton, MA. Address correspondence and reprint requests to Sflren Boysen, DVM, Tufts University School of Veterinary Medicine, 200 Westboro Road, North Grafton, MA 01536. Received June 27, 2002; accepted for publication January 13, 2003. ciated with GI perforation often reflect sepsis and the sys- temic inflammatory response syndrome, and include abnor- mal body temperature, altered mental status, bright red or pale mucous membranes, altered capillary refill time, ic- terus, tachypnea, tachycardia, bradycardia (noted in cats), bounding or weak peripheral pulse, hypotension, abdominal pain, altered albumin levels, altered white blood cell count, thrombocytopenia, elevated liver enzyme levels, and vari- able blood glucose value^.^-^ Presurgical confirmation of GI perforation is challenging, commonly relying on the detection of pneumoperitoneum on survey radiographs or the leakage of contrast medium on an upper GI series. The finding of septic inflammation on cytologic analysis of peritoneal fluid is often seen with GI perforation but is not specific, and other causes of septic peritonitis must be ruled out. Ultrasonography has been used to identify GI perforations in pe~ple.~.’*’~ To our knowledge, there are no studies that have evaluated the use of sonography in the diagnosis of GI perforation in the dog and cat. The purpose of our study was to identify and de- scribe the sonographic features in dogs and cats with con- firmed GI perforation. 556