Surgical Anatomy of the Gastrointestinal Tract in Cats.

In cats, the gastrointestinal tract is one of the regions in which surgical procedures are most frequently performed by veterinary surgeons; therefore, knowledge of the surgical anatomy of the feline gastrointestinal tract is of high importance. The main surgical procedures performed include gastrotomy, gastrectomy, enterotomy, and enterectomy, as well as procedures in the liver and pancreas. There are also anatomical differences between dogs and cats, increasing the need for deep knowledge of the anatomy treated in the different surgical approaches. The aim of the present review is to describe in detail the anatomy of the gastrointestinal tract in cats highlighting the anatomical regions of significant importance in different surgical procedures.

Evaluation of Survival of Subdermal Plexus Skin Flaps in 8 Cats After Injection of Platelet Rich Plasma.

The aim of the present study was to evaluate the effect of platelet-rich plasma injection on the survival of experimentally developed subdermal plexus skin flaps in cats. Two flaps, 2 cm wide and 6 cm long were created bilaterally in the dorsal midline in 8 cats. Each flap was randomized to 1 of 2 groups: platelet-rich plasma injection and control. After flap development, the flaps were immediately placed back on the recipient bed. Then 1.8 mL of platelet-rich plasma was equally injected into 6 different parts of the treatment flap. All flaps were evaluated macroscopically daily and on days 0, 7, 14, and 25 by planimetry, Laser Doppler flowmetry, and histology. Mean flap survival on day 14 was 80.437 % (±22.745) for the treatment group and 66.516 % (±24,12) for the control group with no statistically significant difference between the 2 groups (P = .158). Histologically, a significant difference was found between the base of the PRP and the control flap in edema score on day 25 (P = .034). In conclusion, there is no evidence to support the use of platelet-rich plasma in subdermal plexus flaps in cats. However, the use of platelet-rich plasma may aid in reducing edema of subdermal plexus flaps.

Evaluation of the Effectiveness of Medical-Grade Honey and Hypericum Perforatum Ointment on Second-Intention Healing of Full-Thickness Skin Wounds in Cats.

This study aimed to determine the effects of two topical treatments on second-intention wound healing in cats. Eight 2 × 2 cm full-thickness wounds were created, four on each side of the dorsal midline of eight laboratory cats, to receive either medical-grade honey ointment (MGH) and its control (HC), or Hypericum-based ointment (HP) and its control (HPC). MGH or HP ointment was applied to four wounds on the same side, while the remaining four were used as controls, chosen at random. Planimetry, laser Doppler flowmetry, daily physical examinations, and histologic examinations on days 0, 7, 14, and 25 were used to assess the healing of wounds. Tissue perfusion was better in the MGH-treated (2.14 ± 0.18 mm/s) and HP-treated wounds (2.02 ± 0.13 mm/s) than in the untreated controls HC (1.59 ± 0.11 mm/s) and HPC (1.60 ± 0.05 mm/s), respectively (p = 0.001). Histopathology revealed that the median edema score was lower in the MGH-treated (2; range 1-4) compared to the HC-treated wounds (3; range 2-4) on day 7 (p < 0.05). The median angiogenesis score was higher on day 7 in the MGH-treated (2; range 1-3) compared to the HP-treated wounds (2; range 1-2) (p = 0.046). The fibroblast concentration was increased in the MGH-treated wounds (3.5; range 3-4) compared to the HP-treated wounds (3; range 2-4) on day 25 (p = 0.046). MGH and HP increased tissue perfusion compared to the untreated controls. The MGH-treated wounds had histologic parameters superior to the HP-treated wounds regarding angiogenesis and fibroblast concentration in cutaneous wound healing in cats. Topical application of MGH and HP did not accelerate the healing process of feline cutaneous wounds.

Locally Injected Autologous Platelet-Rich Plasma Improves Cutaneous Wound Healing in Cats.

Cutaneous defects in cats are commonly encountered in clinical practice, and healing can be accomplished by first or second intention. Platelet-rich plasma (PRP) is characterized by a plasma concentration containing a large number of platelets in a small volume of plasma. The objective of the present study was to record the efficacy of PRP infiltration in open wounds in laboratory cats. Six wounds were created in the dorsal midline of eight laboratory cats, with the wounds of one side designated as the PRP group and the wounds of the other side as the control group. Wound healing was evaluated by daily clinical examination, planimetry, laser Doppler flowmetry, and histologic examination on days 0, 7, 14, and 25, and by measurement of metalloproteinases (MMPs)-2 and -9 and tissue inhibitor metalloproteinase (TIMP)-1 on days 0, 14, and 25. Based on the results of the present study, the mean time for full coverage with granulation tissue was shorter in the PRP group, the mean contraction and total wound healing percentage were increased compared to the control group, and finally, the perfusion measured with laser Doppler flowmetry was higher in the PRP group during all examination days. In conclusion, this is the first study focusing on the topical application of PRP in the treatment of open wounds in laboratory cats, and our results are encouraging-showing a more rapid healing in the PRP group.

Contrast enhanced computed tomography assessment of superficial inguinal lymph node metastasis in canine mammary gland tumors.

Mammary gland neoplasms are predominant in dogs. However, sentinel lymph node (SLN) status assessment criteria have not been established for these cases. In this retrospective, secondary analysis, diagnostic case control study, CT images of 65 superficial inguinal SLNs were obtained before and 1, 3, 5, and 10 min after intravenous administration of contrast agent (iopamidol 370 mgI/mL). The presence and degree of postcontrast enhancement were assessed, by means of the median absolute density value and the maximum absolute density value at any time point in the center and in the periphery of each SLN measured in Hounsfield units (HU), before and after contrast agent administration. These values were compared with histopathological findings postsurgical excision. Receiver operating characteristic analysis was conducted. The absolute density values ranged widely at each time point and within each group of nodes (negative, positive, control group). At all time points, the median density value in the center and in the periphery was significantly higher in metastatic than in non-metastatic SLNs (P ≤ .014). Among the parameters tested, the median absolute density value measured in the periphery of the SLN 3 min after injection showed the highest sensitivity, specificity, and accuracy (AUC) (87.5%, 82.1%, and 92.1% respectively), with a cutoff value of 50.9 HU. The maximum absolute density value at any time point in the center and periphery of the SLNs was also significantly higher in metastatic SLNs compared to non-metastatic (P ≤ .001). With a cutoff value of 59.5 HU, the maximum absolute density value in the periphery of the SLN displayed high sensitivity and specificity (87.5% and 89.3%, respectively). The results of this study support the hypothesis that contrast enhanced CT imaging may aid in the assessment of SLN metastasis in dogs with mammary gland neoplasms.

Surgical Management of Feline Extrahepatic Biliary Tract Diseases.

Extrahepatic biliary obstruction occurs infrequently in cats. Pathophysiology of biliary obstruction is characterized by cholestasis, obstruction, inflammation, and exudation. Clinical signs and laboratory examination findings are nonspecific. Ultrasonographic examination of the biliary tract aids significantly in diagnosis. The aims of feline biliary surgery are to determine the underlying cause and extent of the obstruction, restore bile flow to the gastrointestinal tract, and prevent bile leakage and subsequent peritonitis. Surgical techniques to restore bile flow and decompress the biliary distension include cholecystostomy tube placement and choledochal stenting, cholecystectomy, choledochotomy, and biliary diversion procedures. Surgical management of extrahepatic biliary obstruction carries a fair to guarded prognosis. Cats undergoing biliary diversion procedures have poorer outcomes than those undergoing nondiversion procedures. Cats with neoplastic involvement have significantly shorter lives than those with inflammatory involvement.

Jackson-Henderson technique for the revision surgery following PDA rupture in a dog.

A 3-month-old female intact Maltese dog, was referred for further investigation and management of a patent ductus arteriosus (PDA), which was diagnosed with a grade V murmur during thoracic auscultation and a palpable thrill in the left third intercostal space during routine vaccination. Echocardiographic findings included left ventricle dilatation, high velocity continuous ductal flow in the pulmonary valve and a patent ductus arteriosus. Hematological and biochemical abnormalities were not detected. A left forth intercostal thoracotomy was performed and during dissection, the medial wall of the duct was perforated resulting in hemorrhage. Digital pressure was applied over the ductus and bleeding ceased. An attempt for further dissection aggravated bleeding so it was decided to abandon surgery and to reoperate the dog using a different technique. Three months after surgery a second procedure was scheduled. A Jackson-Henderson technique was chosen for the ductus ligation, which was completed through a left fourth intercostal thoracotomy and the dog was discharged 2 days postoperatively. The dog was reexamined at 2 and 8 months after surgery and found with no clinical evidence of heart disease. In conclusion the Jackson-Henderson technique was used in the second surgery for closure of the ductus in order to avoid dissection of the medial aspect of the ductus, where adhesions were formed and the dog was free of clinical signs of heart disease 2 and 8 months postoperatively.

Bilothorax Associated with Bile Peritonitis in a Dog with No Diaphragmatic Disruption: A Case Report.

A 4-year-old intact male mixed-breed dog was presented with vomiting and severe depression of 6-day duration after being struck by a car 2 weeks before presentation. Clinical examination revealed hypothermia, respiratory difficulty, jaundice, and a bicavitary (pleural and peritoneal) effusion. Hematological and biochemical abnormalities included neutrophilic leukocytosis, increased total bilirubin concentration, and increased serum lipase activity. Biochemical and cytological evaluation of both abdominal and thoracic fluids were suggestive of bilious effusions. During celiotomy, a rupture of the cystic duct was observed, which necessitated cholecystectomy. A diaphragmatic rupture was not found. A thoracostomy tube was inserted in the right pleural space, and continuous suction was maintained for 48 hours. The dog was discharged 20 days after surgery and no abnormalities were detected on either blood tests or ultrasonographic examinations of the thorax and abdomen on follow-up examination 7 months after surgery. The presence of a bilothorax should be considered in animals with bile peritonitis, grossly intact diaphragm and pleural effusion. The exact mechanisms of the development of bilothorax are unclear, but the transport of bile through microscopic congenital or acquired weaknesses or defects of the diaphragm, via abdominal lymphatics penetrating the diaphragm and draining into the thoracic lymphatics represent the most probable route.