JAVMA News
Pet reptiles and amphibians can give veterinarians interesting work with varying degrees of difficulty, but owners of such pets rarely seek veterinary care. In other news, a virus that has killed about 7 million pigs can potentially cause multiple outbreaks on individuals farms in the same year. See page 152
Letter to the Editor
See page 172
Theriogenology Question of the Month
See page 179
Anesthesia Case of the Month
See page 183
Evaluation of the perioperative analgesic efficacy of buprenorphine, compared with butorphanol, in cats
Buprenorphine is frequently used in cats during the postoperative period to manage signs of pain and has the advantage of only rarely causing dysphoria or vomiting. Results of a study involving healthy cats undergoing ovariohysterectomy suggest that it is also appropriate for perioperative use. Administration of buprenorphine (0.02 mg/kg [0.009 mg/lb], IM) before surgery and during wound closure provided adequate analgesia for 6 hours following surgery, whereas administration of butorphanol did not. A validated multidimensional composite scale was used to assess signs of pain starting 20 minutes after extubation and continuing for up to 360 minutes. All cats from the butorphanol group required rescue analgesia. See page 195
Appendicular osteosarcoma in small-breed dogs
Appendicular osteosarcoma is the most common primary bone tumor in dogs, but primarily affects large-breed dogs. A review of medical records for 51 small-breed dogs (ie, dogs weighing ≤ 15 kg [33 lb]) with a histologic diagnosis of appendicular osteosarcoma found that tumor histologic grade and mitotic index were subjectively lower and median survival time following amputation of the affected limb without adjuvant chemotherapy was longer, compared with values reported for large-breed dogs. Results indicated no significant advantage in MST for dogs that underwent curative-intent treatment versus dogs that underwent amputation only, and further investigation of the importance of adjuvant chemotherapy is warranted. See page 203
Fluid production and seroma formation after placement of closed suction drains in clean subcutaneous surgical wounds of dogs
Surgical drains are commonly used following soft tissue surgical procedures, but there are no clear standards for determining when closed suction drains should be removed. In a review of medical records for 77 dogs in which a subcutaneous closed suction drain was placed following a surgical procedure, the most common complications were dehiscence (n = 18), seroma formation (14), and infection (4). Dogs that developed a seroma had significantly greater total drain fluid volume relative to body weight and greater fluid production rate at 24 and 72 hours. Dogs in which drains were removed when fluid production rate was > 0.2 mL/kg/h (0.09 mL/lb/h) were significantly more likely to develop a seroma. See page 211
Ethylene-vinyl alcohol copolymer as a liquid embolic agent to treat a peripheral arteriovenous malformation in a dog
An 11-year-old Tibetan Mastiff was evaluated because of a visibly enlarged blood vessel and progressively worsening swelling of the right hind limb. A bruit was auscultated over the affected region, and ultrasonography revealed an artery with turbulent flow that communicated with venous drainage. A CT scan confirmed the presence of an arteriovenous malformation. Embolization of the AVM with ethylene-vinyl alcohol copolymer dissolved in dimethyl sulfoxide was elected. The circumference of the abnormal paw was 51 cm before the procedure and 22.9 cm at 4 weeks after the procedure. Additionally, the gait of the dog dramatically improved. No complications associated with the procedure developed. See page 216
Cyclophosphamide intoxication because of pharmacy error in two dogs
An 8-year-old Yorkshire Terrier and 5-year-old West Highland White Terrier were evaluated because of cyclophosphamide intoxication. Both dogs received cumulative doses of approximately 1,080 mg of cyclophosphamide/m2 after cyclophosphamide was erroneously dispensed instead of cyclosporine by different pharmacies. Both dogs became lethargic. One had anorexia, vomiting, and diarrhea within 2 days, and the other developed anorexia 7 days after initiation of cyclophosphamide administration. The dogs were evaluated 9 and 11 days after administration of the first dose of cyclophosphamide, and both had severe leukopenia and thrombocytopenia. Both dogs fully recovered after treatment. See page 222
Diagnosis and surgical treatment of a malignant trichoepithelioma of the ear canal in a pet rabbit
Results of contrast-enhanced CT, video otoscopy, and histologic examination of biopsy samples were indicative of severe otitis media and externa and a benign trichoepithelioma in a 10-year-old spayed female Holland Lop–mix pet rabbit (Oryctolagus cuniculus) that was evaluated because of purulent-hemorrhagic discharge from the right ear canal. Total ear canal ablation and lateral bulla osteotomy were performed. Histologic examination of a surgical biopsy sample of the mass indicated malignant trichoepithelioma. Tumor recurrence was detected 22 weeks after surgery. The rabbit was euthanized 33 weeks after surgery because of the large size of the recurrent tumor and declining quality of life. See page 227