Use of mandibular symphysiotomy to allow extensive caudal hemimaxillectomy in a dog

A 5-year-old dog was presented with a large caudal maxillary osteosarcoma, which was causing extreme pain on opening of the mouth. The mass was not resectable through a standard oral approach. This article describes the successful use of mandibular symphysiotomy to allow extensive caudal hemimaxillectomy to remove the mass and provide excellent postoperative quality of life for the dog.     

Use of an ELISA for plasma progesterone to facilitate rabbit husbandry

There is a need for a simple and accurate method for detecting pregnancy in rabbits; the available methods are not ideal and may not provide the diagnosis at an appropriate time for the early remating of non-pregnant animals. This paper describes the use of an ELISA kit to measure progesterone concentrations in rabbit plasma; a qualitative assessment of the results appears to be sufficiently accurate for pregnancy diagnosis, as does the use of serum instead of plasma. The technique can be used to predict ovulation and to distinguish between pregnant and pseudopregnant animals.     

Use of a balloon occlusion catheter to facilitate transarterial coil embolisation of a patent ductus arteriosus in two dogs

Two dogs with a history of coughing and exercise intolerance were suspected to have a patent ductus arteriosus (PDA), and the presence of a type III PDA was confirmed by radiography, electrocardiography, ultrasonography and angiography. Transarterial coil embolisation was carried out by using a modified technique. An occlusion balloon catheter was inserted through a femoral vein and placed at the pulmonary side of the ductus before the embolisation coils were put in place. Both dogs remained healthy during a follow-up period of nine months.     

Severe cardiovascular depression in a cat following a mandibular nerve block with bupivacaine

ObservationsA 12 year old cat was presented for anaesthesia to remove a mandibular squamous cell carcinoma. After intramuscular premedication with dexmedetomidine and methadone, anaesthesia was induced with alfaxalone, administered intravenously (IV) to effect, and maintained with isoflurane vaporized in oxygen, following oro-tracheal intubation. Approximately 5 minutes after performing a mandibular nerve block with 1.16 mg kg^?1 of bupivacaine, the cat developed severe cardiovascular depression. Anaesthetic delivery was discontinued and cardiopulmonary resuscitation instituted. Drug administration consisted of atropine (0.02 mg kg^?1 IV, repeated three times), followed by atipamezole (0.08 mg kg^?1 IV). Dobutamine was subsequently administered (1 μg kg^?1 minute^?1 IV) until cardiovascular performance was considered satisfactory. During recovery from anaesthesia the cat exhibited seizure-like activity, which was controlled by a variable rate infusion of propofol. The cat made an uneventful recovery following discontinuation of propofol infusion, without residual neurological signs, and the surgical procedure was postponed.ConclusionsThis clinical report describes successful management of cardiovascular and neurological complications following a mandibular nerve block with bupivacaine in a cat. Although treatment was successful, the role played by the drugs administered during resuscitation remains uncertain.     

Electrical nerve stimulation to facilitate placement of an indwelling catheter for repeated brachial plexus block in a traumatized dog

A 10-year-old, 7 kg, male mixed breed dog was presented, following a dog fight, with open fractures of the radius and ulna and extensive skin and muscle lesions. Using electric nerve stimulation, an indwelling catheter was positioned in the axillary space and 2 mg kg(-1) bupivacaine was injected. Complete sensory and motor blocks were obtained allowing amputation distal to the non-traumatized tissue and debridement of the limb. The injection of bupivicaine was repeated 5 hours after the first bolus and a similar result was obtained in term of muscle relaxation and pain alleviation. Subsequent injections were not successful in providing the same effect, most likely as a result of catheter displacement and alternate means of analgesia were used.     

Use of ultrasonography to facilitate surgical removal of non-enteric foreign bodies in 17 dogs

Plant material foreign bodies may cause vague clinical signs at the time of initial presentation but can progress to cause persistent or recurrent abscessation, sinus tract formation and debilitating disease, due to migration of the foreign body, severe tissue reaction and secondary infection. Ultrasonography is a non-invasive technique that can be used to identify precisely the presence, location and size of radiolucent foreign bodies. Early identification of foreign bodies using ultrasonography facilitates surgical retrieval before further migration and tissue injury occur. This paper reviews the ultrasonographic findings and outcome in 17 dogs with non-enteric, radiolucent, plant material foreign bodies.     

Femoral fracture repair and sciatic and femoral nerve blocks in a guinea pig

A four‐month‐old, entire male guinea pig was presented for surgical repair of a closed oblique femoral fracture. Analgesia was provided with 30 µg/kg buprenorphine intramuscularly (im) four times a day and 0 · 3 mg/kg meloxicam subcutaneously once a day. The following day, anaesthesia was induced and maintained with 100 µg/kg medetomidine im, 20 mg/kg ketamine im, 30 µg/kg buprenorphine im and isoflurane in oxygen. Femoral and sciatic nerve blocks were performed with bupivacaine. The fracture was reduced and aligned using an intramedullary 1 · 4 mm K‐wire and a 3 metric polydioxanone cerclage. Three weeks postoperatively remodelling and callus formation was documented, with no evidence of complications. Complete union was present 14 weeks postoperatively.     

Use of 3D printer technology to facilitate surgical correction of a complex vascular anomaly with esophageal entrapment in a dog

A 10 week old female intact Staffordshire terrier was presented with a total of five congenital cardio-thoracic vascular anomalies consisting of a patent ductus arteriosus (PDA) with an aneurysmic dilation, pulmonic stenosis, persistent right aortic arch, aberrant left subclavian artery and persistent left cranial vena cava. These abnormalities were identified with a combination of echocardiogram and computed tomography angiography (CTA). The abnormalities were associated with esophageal entrapment, regurgitation, and volume overload of the left heart with left atrial and ventricular enlargement. A 2 cm diameter aneurysmic dilation at the junction of the PDA, right aortic arch and aberrant left subclavian artery presented an unusual surgical challenge and precluded simple circumferential ligation and transection of the structure. A full scale three dimensional model of the heart and vasculature was constructed from the CTA and plasma sterilized. The model was used preoperatively to facilitate surgical planning and enhance intraoperative communication and coordination between the surgical and anesthesia teams. Intraoperatively the model facilitated spatial orientation, atraumatic vascular dissection, instrument sizing and positioning. A thoracoabdominal stapler was used to close the PDA aneurysm prior to transection. At the four-month postoperative follow-up the patient was doing well. This is the first reported application of new imaging and modeling technology to enhance surgical planning when approaching correction of complex cardiovascular anomalies in a dog.     

Mepivacaine local anaesthetic duration in equine palmar digital nerve blocks

REASONS FOR PERFORMING STUDY: Perineural analgesics are used for lameness diagnosis but the duration of effect, knowledge of which would provide valuable information when performing subsequent blocks, is unknown. OBJECTIVE: To evaluate the duration of a palmar digital nerve block using force plate measurements. METHODS: Ten horses diagnosed with unilateral navicular syndrome were trotted at range of 3 +/- 0.15 m/sec over a force plate to record ground reaction forces for 5 trials of each forelimb. Data were recorded before nerve block, and then at 15 mins, 1, 2 and 24 h post nerve block. RESULTS: Before nerve block, peak vertical force (mean +/- s.e.) was significantly higher in the contralateral forelimb (CL = 5345 +/- 188 N) than in the lame forelimb (L = 4256 +/- 204 N; P<0.05). At 15 mins post nerve block there was no significant difference between the 2 forelimbs (CL = 5140 +/- 184 N; L = 5126 +/- 129 N), and this remained the case for 1 h. By 2 h, the mean score for the lame leg had decreased (L = 4642 +/- 182 N) but was still greater than preblock. By 24 h, vertical forces had returned to preblock values. CONCLUSIONS: The palmar digital nerve block was fully effective between 15 mins and 1 h. The analgesic effect began to subside between 1 and 2 h but sufficient analgesia persisted to affect gait characteristics beyond 2 h. POTENTIAL RELEVANCE: When using a palmar digital nerve block, it is important to perform lameness evaluations between 15 mins and 1 h to be sure of effective nerve blockade.     

Injection techniques for auricular nerve blocks in the rabbit cadaver

ObjectiveTo describe the landmarks for localization and to determine the methodology and volume of methylene blue dye to adequately stain the auricular nerves in rabbit cadavers.Study designProspective, randomized, cadaveric study.AnimalsA total of 26 rabbit cadavers (Dutch-Belted and New Zealand White breeds).MethodsPart I: anatomical dissections were performed to identify the sensory auricular nerves and to establish the ideal injection approach and volume of dye required for nerve staining. Part II: a single injection technique using 0.1 mL kg^–1 dye was evaluated for staining the greater auricular nerve and two techniques (perpendicular and angled needle approaches) using 0.075 mL kg^–1 dye were evaluated for the auriculotemporal nerve. Dye spread was evaluated through cadaveric dissections and nerve staining graded using a 0–2 point scale. Injections were considered successful if the nerve was stained circumferentially. Cadavers were assessed for staining of the mandibular nerve owing to the close proximity to the auriculotemporal nerve. Fisher’s exact test and mixed effects logistic regression model were used for statistical analysis.ResultsThe greater auricular nerve was stained in 24/27 (88.9%) injections. The auriculotemporal nerve was stained in 7/12 injections (58.3%) with the perpendicular needle approach; staining success increased to 80% (12/15 injections) with the angled needle approach; however, this difference was not statistically significant (p = 0.228). Mandibular nerve staining occurred on seven auriculotemporal injections with no statistically significant difference in the incidence of nerve staining between techniques.Conclusions and clinical relevanceResults suggest that the auricular nerves in rabbit cadavers can be successfully located and stained using anatomic landmarks and the described injection techniques.     

Efficacy of greater auricular and auriculotemporal nerve blocks performed in rabbits

ObjectiveTo evaluate the efficacy, duration and safety of greater auricular and auriculotemporal nerve blocks in rabbits.Study designProspective, randomized, crossover, experimental study.AnimalsA total of 11 healthy adult Dutch-belted rabbits.MethodsThe rabbits underwent general anesthesia and injections of the greater auricular and auriculotemporal nerves using either bupivacaine (0.3 mL kg^–1, 0.5%) or the same volume of saline. After anesthesia, the efficacy and duration of nerve blocks were assessed using analgesiometry forceps on the pinna and cotton-tipped applicators within the vertical ear canal. Rabbits were monitored for abnormal carriage of the ear and auriculopalpebral nerve block of the ipsilateral eye. Body weight, food intake, fecal output and fecal pellet diameter were measured daily for 6 days after the nerve blocks were performed and compared with baseline to assess short-term effects.ResultsThe greater auricular nerve was successfully blocked in 12/16 (75%) ears for mean ± standard deviation duration of 88 ± 52 minutes. In successfully blocked ears, altered ear position was noted in five/16 (31%) cases. The auriculotemporal nerve was blocked in one/16 ears for 120 minutes. The auriculopalpebral nerve was inadvertently blocked in three/16 ears. Food intake and fecal output decreased significantly during the treatment day but returned to pretreatment values after 24 hours. There was no change in body weight or fecal pellet diameter for either treatment.Conclusions and clinical relevanceThe results suggest that duration of the greater auricular nerve block with 0.5% bupivacaine was short-lived in the live rabbit. Auriculotemporal nerve block was only achieved in one ear; therefore, further studies are warranted to evaluate the contribution of these blocks in the pain management of rabbits undergoing auricular surgery.     

Surgical treatment of a mandibular ameloblastic carcinoma with metastases to the mandibular lymph nodes in a pony

A 4-year-old Connemara filly was presented with a rapidly growing oral mass on the right rostrolateral mandible and a right mandibular lymphadenopathy. Radiographs of the rostral mandible revealed a lytic, infiltrative mass consistent with soft tissue and mineralised material, and displacement of tooth 403. A biopsy showed characteristic histopathological features of an ameloblastic carcinoma. Subsequent FNA of the right abnormally firm and enlarged mandibular lymph node confirmed the metastatic spread. Computed tomography of the head was performed for surgical planning, including sentinel lymph node mapping to rule out other lymph node involvement. An aggressive lesion, consistent with soft tissue of the rostral right mandible was identified with intralesional contrast injection showing drainage of contrast within the right mandibular lymph nodes (Sentinel node). Based on the infiltrative and destructive nature reported in ameloblastic carcinoma in humans, a rostral mandibulectomy was performed, along with complete mandibular lymphadenectomy. The horse recovered uneventfully from surgery. In the early post-operative period marked lymphoedema of the ventral mandibular region was observed, which resolved 4–5 days post-operatively. Optimal cosmesis was maintained post-operatively, and no recurrence has been observed to date – 12 months post-surgery.     

Comparison of ultrasound- and electrostimulation-guided nerve blocks of brachial plexus in dogs

Objective

To compare the effectiveness of ultrasound- and electrostimulation-guided nerve blocks of the brachial plexus and to determine whether ultrasound guidance is feasible in conscious dogs.

Proximal mandibular nerve block, using electrolocation, for rostral mandibulectomy in a geriatric dog

We describe a case of proximal mandibular nerve block with ropivacaine, using electrolocation, for perioperative pain management in a geriatric dog undergoing rostral mandibulectomy. The patient did not require intraoperative analgesia or analgesic supplementation for 8 h after the end of the surgery.     

Hypoprothrombinemia secondary to administration of sulfaquinoxaline to dogs in a kennel setting.

Sulfaquinoxaline, a coccidiostat readily available to the public, was mixed in the drinking water for this purpose by the owner. Secondary to its use, a bleeding disorder attributable to hypoprothrombinemia developed in several dogs. Clinical signs of bleeding ceased 24 hours after institution of vitamin K1 and discontinuation of sulfaquinoxaline in the drinking water. This report should remind veterinarians that drugs and medications readily available to the public may have adverse effects in animals, and such problems should be investigated whenever multiple dogs in a common setting are affected with the same clinical problem.     

Use of intralesional formalin administration for treatment of a subepiglottic cyst in a horse

CASE DESCRIPTION: A 4-year-old horse was evaluated for chronic coughing, mucopurulent nasal discharge, and failure to thrive. CLINICAL FINDINGS: Endoscopy was performed on the larynx, pharynx, and trachea and revealed an approximately 2-cm fluctuant subepiglottic cyst. TREATMENT AND OUTCOME: The subepiglottic cyst was treated with intralesional formalin administration. Following 2 injections, 2 weeks apart, the cyst was completely resolved with no evidence of scarring or epiglottic deformity. CLINICAL RELEVANCE: Findings suggest that intralesional formalin administration for treatment of subepiglottic cysts may be a minimally invasive, economically suitable alternative to surgical treatments.