28 Aug 2017
Alex Gough presents a review of some of the latest research in veterinary medicine.
Alex Gough
Job Title
The stress of hospitalisation, as well as the disease for which hospitalisation was required, may affect gastrointestinal motility and pH.
Warrit et al1 performed a study in 12 healthy adult dogs to assess gastrointestinal pressure, transit time and pH using a wireless motility capsule. The study was performed in two phases. The first involved administration of the capsule at the hospital followed by discharge to perform normal routines. In the second, the dogs remained hospitalised and underwent regular leash exercise and radiography. In one dog, the capsule failed to pass out the stomach and was excluded from the analysis. The median gastric emptying time during hospitalisation was significantly longer than when the dogs were at home. However, other parameters, such as pH and motility in small and large intestines, were similar in the hospitalised dogs than the dogs at home.
The authors concluded hospitalisation can delay gastric emptying, which has implications for assessment of motility disorders and transit of oral medications.
The adrenocorticotropic hormone (ACTH) stimulation test is used in the diagnosis and monitoring of hyperadrenocorticism and hypoadrenocorticism. ACTH is IV administered, with blood tests for cortisol levels being taken before and after administration. However, IV injections are sometimes erroneously given SC.
Johnson et al2 performed a prospective study to compare the results of an ACTH stimulation test when ACTH was given IV or perivascularly. Ten healthy dogs and 10 dogs with hyperadrenocorticism underwent ACTH stimulation testing with perivascular and IV ACTH. The tests were randomised, so 5 healthy dogs and 5 cushingoid dogs received the IV dose first, and vice versa for the other 10 dogs. No significant differences in post-ACTH cortisol concentration were seen for the healthy dogs or the cushingoid dogs when comparing route of injection.
The authors concluded perivascular ACTH injection does not appear to significantly affect the results of ACTH stimulation testing in healthy dogs and dogs being treated with trilostane for Cushing’s disease.
Neutering clinics associated with animal shelter charities aim to reduce unwanted populations of dogs and cats. To achieve this, they need to perform a high volume of procedures, leading to concerns about the quality of medical care given.
Levy et al3 performed a study to assess the perioperative mortality rate in a high-volume neuter clinic in the US. More than 100,000 dogs and cats were included in the study, in which a mortality log was kept. Perioperative deaths were defined as occurring within 24 hours of neutering.
A total of 34 out of 71,557 cats and 4 out of 42,349 dogs died in the perioperative period. Mortality rate was twice as high for females as males, and five times as high for cats as dogs. Nevertheless, the overall mortality rate was low at only 0.03%. The authors believe the low mortality rate may be due to the good health of the generally young population and the ability of the surgical team performing a high volume of a limited number of procedures.
Pyothorax is a life-threatening infection of the pleural space. Many cases can be treated with medical management, such as antibiotics and chest drains, but some require surgery.
Scott et al4 performed a retrospective study of 14 dogs with pyothorax that had undergone video-assisted thoracic surgery (VATS). After VATS exploration, mediastinal debridement, biopsy, lavage and/or thoracostomy tube placement were carried out. Two of the dogs required conversion to full thoracostomy to resect mediastinal tissue. Ten cases were idiopathic, two were due to penetrating gastric foreign bodies and two due to migrating plant material. One patient had a recurrence of pyothorax 17 months later. All dogs were discharged with resolution of clinical signs.
The authors concluded VATS can help with the treatment of uncomplicated pyothorax.
Tumour proliferation markers can help with staging and prognosis, and potentially help guide treatment. Mestrinho et al5 evaluated Ki-67 and proliferating cell nuclear antigen (PCNA) immunohistochemistry markers in 36 oral squamous cell carcinomas in dogs. Grade I tumours were found to be more common in the gingiva and buccal mucosa, and grade III tumours in the gingiva and tonsillar regions. Grade II tumours were most common. The expression of PCNA was associated with tumour grade and Ki-67 was associated with lymph node metastasis.
The authors noted, although these results are only preliminary, they help explain the difference in tumour behaviour in different locations and assist in staging.
Although cytology is a useful technique due to its ability to give rapid answers, gastrointestinal endoscopy usually relies on biopsies taken for histopathology to assist in diagnosis. Maeda et al6 performed a study to assess the usefulness of endoscopic cytology in the diagnosis of chronic enteritis and intestinal lymphoma in dogs. A total of 167 dogs with chronic gastrointestinal disease were included in the study.
Histopathological diagnosis revealed 93 cases of lymphoplasmacytic enteritis, 5 cases of eosinophilic enteritis, 45 cases of small cell intestinal lymphoma and 24 cases of large cell intestinal lymphoma. In 81.4% of cases, cytological diagnosis agreed with histological diagnosis. Cytology had a 98.6% sensitivity and 73.5% specificity for distinguishing lymphoma from chronic enteritis.
The authors concluded endoscopic cytology can aid in differentiating intestinal inflammation and lymphoma.
The ability to access diagnostic images in the surgical theatre can assist the surgeon in planning and mapping procedures. Allowing the surgeon to control the imaging software during the surgical procedure can reduce mistakes from communication. Appleby et al7 performed a study to compare a standard computer mouse against a Nintendo Wii games console controller (Wiimote). Surgeons were asked to complete a survey after using the Wiimote and mouse.
Use of the mouse for image navigation was preferred to using either the Wiimote or no device at all, and was rated higher for handling, accuracy and efficiency.
The authors recommended the use of intraoperative image navigation devices to assist surgeons in theatre.
