13-year-old, male castrated, Labrador Retriever presented for lethargy, vomiting and an episode of collapse. Bloodwork consistent with iron deficiency (microcytic, hypochromic, regenerative anemia) and blood loss. Abdominal ultrasound found pedunculated nodules of the pyloric antrum (1.3 cm wall thickness) with focal nodule disrupting wall layering of the mid jejunum (1.7 mm wall thickness and 1.5 cm in length). Thoracic radiographs were unremarkable.
Intestinal resection and anastomosis (RA) were performed along with a gastropexy and biopsies of the liver and stomach.
The dog returned 6 days later with signs lethargy and vomiting. Point of care bloodwork showed mild anemia and hypokalemia. Based on timing since surgery and clinical signs, there was concern for dehiscence. Abdominal ultrasound was repeated (video below).
What's Your Diagnosis?
Hyperechoic peritoneal fat and anechoic peritoneal effusion is identified throughout the abdomen. The previous resection and anastomosis site is identified. One of the walls associated with the RA site has a hypoechoic expansion of echogenic fluid that measures over 2.0 cm long. Multiple roughly linear hyperechoic tracts can be seen extending from the intestinal wall lumen into this hypoechoic region. The hypoechoic region is poorly vascularized. There may be a small amount of free gas in the abdomen. The site of stomach biopsy was normal (not in video). No other abnormalities are observed.
- Focal echogenic fluid accumulation at the site of a jejunal RA site
- Suspect gas accumulation in the wall and in the fluid pocket of the RA site
- Loss of wall layering, focally at the RA site
- Small volume anechoic peritoneal effusion and pneumoperitoneum, expected 6 days post-op
- Generalized peritonitis, also expected though perhaps slightly greater than expected around the RA site
Indeed, a pocket of fluid around the wall of an RA site can be seen this soon after surgery. However, the echogenicity of the fluid and the suspected gas tracking into the fluid pocket raised concern for early dehiscence. Coupled with the timing of the deteriorating clinical signs, these findings prompted us to aspirate the free peritoneal effusion AND the pocket of fluid around the RA site for cytological evaluation.
- Cytology of fluid pocket: Marked septic (rods) neutrophilic inflammation
- Cytology of the peritoneal effusion: Inflammatory without bacteria
- Gastric biopsies: Hyperplasia, lymphoplasmacytic and neutrophilic gastritis; Jejunal mass biopsy: fibromuscular polyp, completely excised
- Dog returned to surgery for RA site revision. Leakage of intestinal contents at the TA staple site (with omental adhesions) was confirmed. Jejunal resection and anastomosis was performed again, with not further complications.
After an RA, ultrasonic findings that have been reported include: loss of wall layering, pneumoperitoneum, decreased gastrointestinal motility, increased wall thickness, corrugation, focal/generalized peritoneal effusion, and increased echogenicity of omental/mesenteric fat. Matthews, et al. reports focal fluid accumulation around enterotomy sites as normal, reaching maximum dimensions 3 days post-op in 7 of 8 dogs, with progressive resolution over 10 days in most dogs. Leakage at an RA site typically occurs 3 to 5 days after surgery, during the lag phase of healing, when the tissue is the weakest (DePompeo et al).
In this dog, the timing of the clinical deterioration corresponded with the general time of the lag phase in healing. Furthermore, the echogenicity of the fluid was not anechoic as described in normal healing of enterotomies. Gas did not seem localized to the lumen of the intestine, prompting the additional diagnostics.
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