Sedation with dexmedetomidine is associated with transient gallbladder wall thickening and peritoneal effusion in some dogs undergoing abdominal ultrasonography

BACKGROUND: Dexmedetomidine often is used for sedation before or during abdominal ultrasonography. The effect of dexmedetomidine on gallbladder wall thickness is unknown. HYPOTHESIS/OBJECTIVES: To investigate the relationship between dexmedetomidine administration and gallbladder wall thickening in dogs. The hypothesis was that sedation with dexmedetomidine will cause transient gallbladder wall thickening. Gallbladder wall thickness will be associated with duration of sedation and recumbency position. ANIMALS: Seventy‐nine client owned dogs and 10 healthy research dogs. METHODS: A prospective observational study (n = 79) was used to establish the prevalence of gallbladder wall thickening (> 2.0 mm) after sedation with dexmedetomidine. A randomized, crossover study (n = 10) was used to evaluate the effect of time and recumbency position on the development of gallbladder wall thickening. Linear mixed models were used. RESULTS: The proportion of client‐owned dogs that developed gallbladder wall thickening was 24.05% (19/79; 95% confidence interval [CI], 15.1%‐35.0%) with a median dose of dexmedetomidine of 5.0 μg/kg (range, 2.0‐12.5 μg/kg). After sedation, the proportion of research dogs that developed gallbladder wall thickening in left lateral (5/10, 50%; 95% CI, 18.7%‐81.3%) and dorsal (7/10, 70%; 95% CI, 34.8%‐93.3%) recumbency did not differ significantly (P = .45). Gallbladder wall thickening developed within 20 to 40 minutes. Duration of sedation was significantly associated with thickening of the gallbladder wall (P < .001). Five dogs developed 9 instances of peritoneal effusion in both lateral (5) and dorsal (4) recumbency. CONCLUSIONS AND CLINICAL IMPORTANCE: Sedation with dexmedetomidine is associated with gallbladder wall thickening (> 2.0 mm) and peritoneal effusion that could be confused with pathologic etiologies.