Intestinal dehiscence and mortality in cats undergoing gastrointestinal surgery.

OBJECTIVES: The aim of this study was to determine the incidence of and risk factors for both gastrointestinal (GI) incisional dehiscence and mortality in a large cohort of cats undergoing GI surgery. We hypothesized that cats with preoperative septic peritonitis (PSP), systemic inflammatory response syndrome (SIRS) or sepsis would have higher GI dehiscence and mortality rates than unaffected cats. METHODS: A medical records search identified cats with surgically created, full-thickness incisions into their stomach, small intestines or large intestines. Preoperative data, including signalment, clinical signs, comorbidities, surgical history, current medications, presenting physical examination findings, complete blood counts and serum biochemistry values, were collected. It was determined whether or not cats had PSP, SIRS or sepsis at admission. Intraoperative data, final diagnosis and postoperative variables such as vital parameters, bloodwork and (if applicable) the development of GI dehiscence or mortality were noted. Postoperative follow-up of at least 10 days was obtained in survivors. RESULTS: In total, 126 cats were included. One cat developed GI dehiscence following complete resection of a jejunal adenocarcinoma. Twenty-three cats (18.2%) died within 10 days of surgery. Cats with PSP (P = 0.0462) or that developed hypothermia 25-72 h postoperatively (P = 0.0055) had higher odds of mortality in multivariate analysis. Cats with PSP had 6.7-times higher odds of mortality than cats not diagnosed with PSP. CONCLUSIONS AND RELEVANCE: In cats receiving GI surgery, the incidence of GI incisional dehiscence was <1%. Cats with PSP had a higher likelihood of mortality. SIRS was a common finding in cats with septic peritonitis, but was not associated with mortality. Postoperative mortality during the home recovery period might be significant in cats. Future studies evaluating postoperative mortality in cats should consider extending the research period beyond the date of discharge.

Verminous myelopathy secondary to aberrant Dirofilaria immitis migrans was detected in the cervical subarachnoid space of four dogs using MRI and CT.

Aberrant Dirofilaria immitis migrans is a rare cause of neurologic signs in dogs, however, published studies describing the computed tomographic (CT) and magnetic resonance imaging (MRI) characteristics of this problem are currently lacking. The objective of this retrospective case series study was to describe the clinical and imaging findings for four adult dogs with verminous myelopathy due to aberrant Dirofilaria immitis migrans within the cervical subarachnoid space. All dogs were toy breeds, were heartworm antigen positive, had neurologic signs (ranging from cervical hyperesthesia to tetraparesis), and similar MRI findings. In two patients additionally imaged with CT, findings were variable. On MRI, each dog had a single large, dorsal- to laterally located, intradural-extramedullary, fusiform mass with characteristic stippled, mixed T2-weighted and T1-weighted signal intensity, hypo-to-iso T1-weighted signal intensity, and spinal cord compression. Nematodes were identified as serpentine or circular subarachnoid structures with low T2-weighted and T1-weighted signal in the sagittal and transverse image planes, respectively. CT (n = 2 dogs) demonstrated focal regions of mildly enhancing intradural-extramedullary spinal cord compression in 1 dog. Dorsal laminectomy and durotomy were performed in two dogs at C3-C4. A C4-5 hemilaminectomy with durotomy and dural biopsy was performed in one dog. Extraction of live, immature adult, female D. immitis worms was performed in three dogs. Operated dogs had complete post-surgical resolution of clinical signs. One dog was euthanized without surgery; necropsy revealed an adult heartworm in the spinal subarachnoid space at C2. Findings indicated that cervical spinal subarachnoid D. immitis aberrant migration should be considered as a differential diagnosis for dogs with this combination of clinical and CT/MRI imaging findings, and that the prognosis may be good with early detection and surgical removal.

Platelet function in cats with hyperthyroidism.

OBJECTIVES: Cats with hyperthyroidism have been reported to develop thromboembolism, with and without echocardiographic abnormalities consistent with hyperthyroidism. The objective of this study was to compare platelet function in cats with hyperthyroidism with euthyroid age-matched cats. We hypothesized that cats with hyperthyroidism have shortened collagen and adenosine diphosphate (C-ADP) closure times as measured with the platelet function analyzer (PFA-100) in comparison with healthy, age-matched controls. METHODS: Sixteen hyperthyroid and nine euthyroid healthy cats >7 years of age were recruited from the hospital population. Platelet function, measured using the C-ADP closure times by the PFA-100, and platelet count were measured in healthy euthyroid cats and cats with hyperthyroidism. RESULTS: Mean ± SD closure times were not significantly different between control (66.3 ± 9.6 s) and hyperthyroid cats (65.9 ± 11.5 s; P = 0.75). The mean ± SD closure times of hyperthyroid cats that either were untreated or received methimazole for ⩽3 weeks (n = 6; mean 68.5 ± 15.4 s) was not different than that of cats treated for >3 weeks (n = 10; mean 64.3 ± 8.9 s; P = 0.57). The mean automated platelet count was higher in the hyperthyroid group than in the control group (P = 0.023). CONCLUSIONS AND RELEVANCE: Platelet function, as measured by closure time under high shear conditions using C-ADP as an agonist, was not affected by hyperthyroidism in this group of cats. Further research is needed to determine if a hypercoagulable state exists in hyperthyroid cats and the potential roles platelets and von Willebrand factor may have.

Neurolymphomatosis caused by T-cell lymphosarcoma in a cat: imaging description and treatment review.

CASE SUMMARY: A 16-year-old domestic shorthair cat was evaluated for acute-onset right pelvic limb monoparesis localized to the sciatic nerve. MRI revealed a homogeneously contrast-enhancing, well-demarcated mass effacing the right sciatic nerve from its intravertebral origin to the end of the viewable field (mid-femur). Abdominal ultrasound revealed thickened small intestinal loops and enlarged mesenteric lymph nodes. Cytology of the small intestine was suggestive of lymphosarcoma. T-cell lymphosarcoma of the sciatic nerve and small intestines was confirmed with incisional biopsy. Treatment consisted of systemic chemotherapy with vincristine followed by the Wisconsin-Madison feline lymphosarcoma protocol, but despite treatment the patient neurologically worsened and was euthanized after 54 days. RELEVANCE AND NOVEL INFORMATION: We present herein one of the first descriptions of neurolymphomatosis in the domestic cat that included post-intravenous contrast MRI. Treatment options based on recommendations for people with neurolymphomatosis include systemic chemotherapy, intrathecal chemotherapy and/or localized radiation chemotherapy. The authors recommend that all cats be screened for concurrent non-neuronal areas of lymphosarcoma before undergoing treatment for neurolymphomatosis, regardless of clinical signs.

Mucous Membrane Color Assessment Variability of Veterinary Students Using Either Colorimetric or Word-Based Scales.

A colorimetric scale has the potential to be very useful as a training tool for students in veterinary training programs. The authors of this report hypothesized that clinically active, graduate level veterinary students would assess mucous membrane color with greater consistency using an image-based system than with traditional word-based techniques. Third- and fourth-year veterinary students were asked to evaluate 10 canine gingival mucosa images and rate them with either an image-based scale designed by the authors or a word-based system. Although the mean absolute deviations from the median values were greater for the word scale (0.22) than for the image scale (0.20) indicating increased variation, mixed model analysis did not demonstrate these differences were significant ( p = .120). Based on this data it is possible that prior image and word-based instruction made it easier for the students to differentiate mucous membrane colors, or that the majority of the students were multimodal learners rather than single-type learners, making previous instruction techniques effective regardless of whether they were visual or read/write based. The authors recommend that future investigators both evaluate previous student instruction and consider administering visual, auditory, read/write, kinesthetic (VARK) tests when investigating potential learning aids in veterinary medicine.