Ultrasound Fast Scanning Before and After Fluid Therapy in the Field as an Aid for the Diagnosis of Gastrointestinal Perforation in a Bobcat (Felis rufus)
Johanna Mejia-Fava1, DVM; Jörg Mayer1, Dr Med Vet, MSc, DABVP (ECM); Shannon P. Holmes2, DVM, MSc, DACVR; Eli B. Cohen2, DVM; Berkeley W. Boone3; Stephen J. Divers1, BVetMed, DZooMed, DACZM, DECZM (Herpetology), FRCVS
A 10-year-old female bobcat (Felis rufus) presented with a three-day history of lethargy, anorexia, and two episodes of vomiting. An emergency field visit was scheduled to perform radiographs and abdominal ultrasonography. She was assessed to be ∼5–10% dehydrated based on decreased skin turgor and tacky mucous membranes. Free peritoneal gas, reduced abdominal serosal detail, and an abnormal appearing right-sided intestinal segment were identified in the lateral and ventrodorsal abdominal radiographs (indirect digital or computed radiographs). However, the emergency field clinicians were not knowledgeable of these abnormalities because the radiographs had to be processed at the UGA-VTH. During an initial complete abdominal ultrasound evaluation, a non-dependent hyperechoic interface with reverberation artifact (intestinal or free gas) and focal intestinal changes suggestive of marked enteritis or peritonitis were identified. Free peritoneal fluid was not present on initial examination. In a focused abdominal sonography for trauma (FAST) scan, made following subcutaneous fluid administration (dose 130 ml/kg), a small volume of anechoic free fluid was present in the peritoneal space. With ultrasound guidance, the fluid was aspirated and was grossly turbid. This fluid was subsequently confirmed as septic suppurative effusion, secondary to a foreign-body-associated intestinal perforation. FAST is well-described in human medicine, and to a limited degree in veterinary literature.1-3 This case represents a novel application of FAST scanning in an emergency field setting in a non-traumatized patient. It illustrates the potential utility of FAST exams for yielding additional and critical clinical information after establishing euvolemia.
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