Characteristics, surgical treatment, and outcomes of injuries involving the tarsus in greyhounds.

Objective: The first objective of this study was to describe the type of tarsal injuries sustained, surgery performed, and postoperative complications in greyhounds presenting to a single veterinary hospital. An additional objective of the study was to determine the surgical site infection (SSI) and explantation rate, and if any variables were associated with an increased risk of SSI and/or explantation. Animals: 116 greyhounds receiving surgical intervention for a tarsal injury. Proceures: Medical records from a single veterinary referral hospital were reviewed retrospectively. Data retrieved included signalment, details regarding the injury, surgical intervention, concurrent castration, surgical/anesthesia times, postoperative management, time to healing, and postoperative complications. In cases that underwent explantation, cause, time from initial surgery, and risk factors were evaluated. Results: The most frequently diagnosed tarsal injuries were fracture of the central tarsal bone (CTB; 57.8%), calcaneal fracture (56.9%) and proximal intertarsal subluxation (34.5%). The most common injury combination was a CTB fracture with a calcaneal fracture (31.9%). In total 115 (99.1%) survived to discharge. Of these, 46 (40.0%) were diagnosed with an SSI and 59 (51.3%) underwent explantation. The most common indication for explantation was SSI. Concurrent medial and lateral surgical approaches was found to be associated with an increased likelihood of SSI and explantation. Clinical relevance: Practitioners performing surgical intervention for tarsal injuries in greyhounds should be aware of the high SSI rate and likelihood that explantation will be required. This risk is elevated for injuries requiring a bilateral surgical approach.

Effect of storage duration on carprofen concentration measurements in dog plasma.

BACKGROUND: Storage of samples may be necessary prior to testing drug levels in certain study designs; however, the effect of storage duration on measured drug levels is not known for all drugs. OBJECTIVES: The objective of this study was to evaluate the stability of carprofen in canine plasma when stored at -80°C for 6 months. METHODS: Six healthy dogs were enrolled (1-10 years old, 17-35 kg) and received compounded carprofen at 2.2 mg/kg orally every 12 h for 2 days. On the third day, blood was collected immediately before the morning dose (trough), then 1 and 6 h after the dose (sampling timepoint). Whole blood was immediately centrifuged, and plasma was stored at -80°C. Plasma carprofen concentration was measured at day 2, week 2 and then monthly for 6 months using reversed-phase high-performance liquid chromatography. The measured carprofen concentrations were analysed statistically using a linear mixed effects model. RESULTS: There was no effect of storage time over 6 months (p = 0.891) on measured carprofen levels. Although there was an effect of sampling timepoint (0, 1 and 6 h) (p < 0.001), the interaction between storage timepoint and sampling timepoint was not statistically significant (p = 1). CONCLUSIONS: Carprofen-laden canine plasma samples can be stored for up to 6 months before analysis with no degradation in carprofen concentrations expected.

Optical coherence tomography for surgical margin evaluation of excised canine cutaneous and subcutaneous tumours.

Currently, intraoperative tumour margin imaging is not routinely utilized in veterinary medicine. Optical coherence tomography (OCT) allows for real-time assessment of tissue morphology of 1-2 mm depth. The aims of this study were (1) to compare the histologic and OCT features of excised canine skin and subcutaneous specimens, and (2) to determine the diagnostic accuracy of OCT for surgical margin evaluation. The authors hypothesized that OCT imaging would correlate well with histopathology and that OCT would be sensitive for detection of incomplete margins. Eighty dogs were prospectively enrolled. Tumours were excised, and the surgical margins were imaged using a spectral domain OCT system. The tumour type and completeness of excision were determined by histopathology. Nine blinded observers received training in OCT image interpretation and were then given a set of OCT images and videos. The observers assigned each image/video a grade from 1 (no tumour) to 4 (tumour) and the results were compared to histopathology. The overall median sensitivity and specificity of OCT imaging for detection of incomplete margins were 86.7% and 84.6%, respectively. A potential limitation is that observers had varied experience with OCT image interpretation, ranging from no prior experience to participating in a previous OCT project. OCT is sensitive for detection of incomplete margins and could be a promising real-time surgical margin imaging modality. Further study is needed to evaluate intraoperative applications of OCT and its impact on tumour recurrence and long-term outcome.

Liver Lobe Torsion in a Guinea Pig (Cavia porcellus).

A 5-year-old, female intact guinea pig (Cavia porcellus) presented for acute inappetence. The abdomen was severely distended and tympanic with moderate discomfort. Radiographs showed gastric distension and displacement. Gastric dilatation and volvulus were suspected. At necropsy, the left lateral liver lobe was torsed at the hilus and infarcted. Histopathology showed regionally extensive coagulative necrosis and markedly congested sinusoids, causing marked hepatic cord atrophy and dissociation. Final diagnoses were severe gastric dilatation with left lateral liver lobe torsion (LLT) and regionally extensive liver infarction, and hemoabdomen. Reports of LLT in guinea pigs are likely underrepresented in the literature. LLTs should be considered in guinea pigs presenting for acute inappetence and abdominal distension. Laboratory tests and abdominal ultrasound can help differentiate LLT from other gastrointestinal pathologies seen in guinea pigs, such as gastric dilatation and volvulus. Early recognition of LLT in guinea pigs could potentially improve patient outcomes. This is the first published report of LLT in a guinea pig.