The Mesh Expansion Method of Suturing Wounds on the Legs of Horses

Wound closure utilizing tension-relieving incisions located in the skin adjacent to the wound of horses was evaluated in three experiments. Healing of lower limb wounds was compared in four treatment groups; wounds sutured under tension, wounds sutured with 7 mm and 10 mm tension relieving incisions, and unsutured controls. The wounds sutured using 10 mm tension relieving incisions healed significantly faster than the other three groups (p > 0.05). The mesh expansion technique was further evaluated in four-week-old granulating wounds. The technique was found to be unsuccessful because the tension relieving incisions that were used were too small and postoperative support was inadequate. The technique was evaluated in two clinical patients, both of which had large metatarsal lacerations. Tension relieving incisions of approximately 15 mm were made and full leg walking bar casts were applied. Both wounds had healed almost completely on removal of the casts four weeks postoperatively.     

Clinical Vignette

This 12-month-old, outdoor intact male cat (Fig. 1) was examined because of an untreated draining nasal lesion. The lesion. initially appeared as small punctures, and progressed ovcr 2 months to an ulcerated draining nodule that gradually enlarged to involve the whole muzzle, extending bilaterally to the medial canthi and having multiple drainage points through overlying necrotic skin. Results of serum feline leukemia virus antigen and feline immunodeficiency virus antibody tests were negative.     

Pheochromocytoma Presenting as Acute Retroperitoneal Hemorrhage in a Dog

Objective: This report describes the perioperative management of a dog with a right adrenal pheochromocytoma that presented with acute retroperitoneal hemorrhage, cardiac arrhythmia and hypertension. Additionally, a summary of pheochromocytoma and the idiosyncrasies of perioperative management of a pheochromocytoma are provided.
Summary: A 7-year old male, neutered, Dalmation was presented for acute collapse, abdominal pain and tachycardia. Physical examination findings were consistent with hypoperfusion concurrent with multiple cardiac arrhythmias and hypertension. Abdominal ultrasound revealed retroperitoneal effusion and a right adrenal mass intimately associated with the caudal vena cava. Incomplete right adrenalectomy was performed. Histopathology confirmed a pheochromocytoma.
Unique information provided: To the authors' knowledge, this is the first definitive report of acute retroperitoneal hemorrhage as the initial clinical manifestation of histologically confirmed adrenal pheochromocytoma in the dog. ( J. Vet Emerg Crit Care 2001; 11(3): 221–227 )     

Arthroscopic Removal of an Osteochondral Fragment from the Middle Phalanx of a Horse

An intraarticular osteochondral chip fracture of the distal dorsolateral aspect of the right hind middle phalanx in a 4-year-old Dutch Warmblood gelding was removed arthroscopically. Accessibility and visibility of the fragment were excellent, and there was minimal soft tissue trauma.     

HYPERCALCEMIC NEPHROPATHY IN THREE DOGS: SONOGRAPHIC APPEARANCE

Persistent hypercalcemia in the dog is most commonly seen as a paraneoplastic syndrome or in association with widespread osteolytic lesions. In high concentrations calcium is a potent nephrotoxin and may cause severe and irreversible renal damage. The ultrasonographic changes in the kidneys of three dogs with hypercalcernic nephropathy are described'and compared with the changes described in the same human condition. It is suggested that ultrasound could be a useful technique for evaluation of the severity of renal damage and the potential return of renal function in such instances.     

In vitro evaluation of the contractile response to endothelin-1 of the circular and longitudinal myometrial layers of the uterine horn of nongravid mares

OBJECTIVE: To characterize the in vitro response of circular and longitudinal myometrial layers of the uterine horn (CMLH and LMLH, respectively) of horses to endothelin (ET)-1 by use of specific ETA (BQ-123) and ETB (IRL-1038) receptor antagonists. SAMPLE POPULATION: Uteruses from 10 nongravid mares in anestrus. PROCEDURE: Muscle strips from the CMLH and LMLH were suspended in tissue baths and connected to force-displacement transducers interfaced with a polygraph. Strips were incubated for 45-minute intervals with no antagonist (control specimens), and 3 concentrations (10(-9), 10(-7), and 10(-5)M) of BQ-123, IRL-1038, or BQ-123 and IRL-1038 before concentration-response curves to ET-1 were generated. Contractile response to cumulative concentrations of ET-1 (10(-9) to 10(-6)M) was quantified by measuring change in the area under the curve (AUC) for the 3-minute period after each ET-1 dose. RESULTS: ET-1 caused concentration-dependent contraction of the CMLH and LMLH specimens. Application of BQ-123 decreased AUC values for both layers. Application of IRL-1038 increased the AUC value for LMLH specimens but did not affect the CMLH value. The combination of BQ-123 and IRL-1038 decreased the AUC value for LMLH tissue and increased that for CMLH tissue. CONCLUSIONS AND CLINICAL RELEVANCE: ET-1 causes contraction of the CMLH and LMLH in nongravid horses. In both layers, ETA receptors mediate contraction but the role of ETB receptors remains unclear. In the LMLH, ETA receptors have a dominant role; the presence of another receptor or receptor subtype within this layer is suggested. These findings support a physiologic role for ET-1 in uterine contractility.     

Hepatic Encephalopathy

Hepatic encephalopathy occurs in a number of different species as a result of either congenital portacaval shunts or acquired liver disease. Despite intensive research, the neurochemical basis of the disorder has not been defined. Theories to explain the cerebral dysfunction that accompanies acute or chronic hepatic failure include 1) ammonia acting as the putative neurotoxin, 2) perturbed monoamine neurotransmission as a result of altered plasma amino acid metabolism, 3) an imbalance between excitatory amino acid neurotransmission, mediated by glutamate, and inhibitory amino acid neurotransmission, mediated by gamma-aminobutyric acid, and 4) increased cerebral concentrations of an endogenous benzodiazepine-like substance.     

Measurement of Muscle Surface Capillary Blood Flow by Laser Doppler Flowmetry

Muscle surface capillary blood flow was measured in the biceps femoris and lateral head of the triceps brachii muscles in six horses before and during halothane anesthesia by using laser Doppler flowmetry. During 90 minutes of anesthesia, muscle surface capillary blood flow was reduced to 20% to 40% of preanesthetic values. Muscle surface capillary blood flow tended to be lower in dependent muscles than in nondependent muscles, and this disparity was greater in the forelimbs than in the hind limbs.     

Use of Isobutyl-Cyanoacrylate Adhesive in Osteosynthesis A Preliminary Study

Isobutyl 2-cyanoacrylate was used to reattach partial-thickness cortical bone fragments from the femur in rabbits. Stability, apposition, callus formation, and inflammation around the fragments were evaluated at 2, 4, 8, and 12 weeks.
All glued bone fragments were stable, compared with 85% of controls. Good apposition was achieved in 95% of the glued bone fragments, compared with 19% of the controls. Analysis of the mean scores for callus formation revealed a significant difference only in the 8 week survival group.
Bony union was noted in 20 of 21 of the glued fragments. No evidence of inflammation was seen around the glue, and viable bone was seen adjacent to the adhesive in many sections. In control legs, 13 fragments had healed by osseous union, two by fibrous union, and in six the chip had resorbed.