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in Journal of the American Veterinary Medical Association

Objective—

To describe the short-and long-term survival rates in horses undergoing ovariectomy for granulosa cell tumors by use of the diagonal paramedian approach.

Design—

Retrospective case study.

Animals—

12 horses with granulosa cell tumors.

Procedure—

A diagonal paramedian approach for unilateral ovariectomy was used for removal of each mare’s granulosa cell tumor. Information about complications and outcomes was analyzed.

Results—

Only minimal complications were detected postoperatively when the diagonal paramedian approach was used, regardless of the preferred technique for ovarian pedicle ligation or incisional closure and the use of pre- and postoperative medications. Clinical signs of moderate or severe postoperative abdominal pain were not evident in any of the 12 horses. Short- and long-term survival rates were 100%.

Clinical Implications—

The diagonal paramedian approach was advantageous for ovarian tumor removal, because the ovary was immediately adjacent to the body wall at a portion of the incision site. Size of the ovary was not a limitation, because muscle tissues at the edges of the incision were flexible and easily retractable. All of these factors improved exposure, decreased traction on the ovary, increased our ability to observe the vasculature, and decreased postoperative morbidity, aiding in the removal of granulosa cell tumors in mares. (J Am Vet Med Assoc 1997;211:204–206)

Free access
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Summary

Postoperative abdominal fluid changes were compared in 2 groups of horses; those undergoing double small-colon resection and anastomosis (n = 10) and those undergoing exploratory celiotomy alone (n = 5). Peritoneal fluid was collected before surgery and on postoperative days 1, 3, 5, and 7. Total and differential nucleated cell counts, rbc numbers, and total protein and fibrinogen concentrations were evaluated. In both groups, all values were significantly higher than normal on the first postoperative day (after small-colon resection and anastomoses, wbc = 130,350 ± 23,310 cells/µl, rbc = 7,389,000 ± 6,234,000 cells/µl, total protein = 3.63 ± 0.16 g/dl; after exploratory celiotomy alone, wbc = 166,620 ± 34,340 cells/µl, rbc = 295,000 ± 86,070 cells/µl, total protein 4.38 ± 0.54 g/dl). The number of total peritoneal nucleated cells and rbc significantly decreased after the first postoperative day, whereas total protein and fibrinogen concentrations, percent neutrophils, and percent mononuclear cells remained unchanged. None of the values had returned to normal by postoperative day 7 (after small-colon resection and anastomoses, wbc = 45,600 ± 8,765 cells/µl, rbc= 95,390 ± 53,380 cells/µl, total protein = 4.39 ± 0.23 g/dl; after exploratory celiotomy alone, wbc= 43,340 ± 7,746 cells/µl, rbc = 12,860 ± 11,790 cells/µl, total protein = 3.92 ± 2.20 g/dl.) The resection and anastomosis group had a significantly lower total protein concentration on the first postoperative day and a significantly higher mean total rbc count over the entire 7-day postoperative evaluation than did horses that underwent celiotomy alone. Other values in the 2 groups of horses did not differ significantly. As a result, there was insufficient evidence to conclude that resection and anastomosis of the small colon in healthy horses causes a different inflammatory response than does manipulation of the intestine alone.

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in American Journal of Veterinary Research

Objective

To evaluate clinical and laboratory findings for horses treated medically for ileal impactions.

Design

Retrospective case series.

Animals

10 horses with primary ileal impaction that were treated successfully with medical treatment alone.

Procedure

Medical records were reviewed for all horses with naturally developing ileal impaction seen at our hospital between 1990 and 1994.

Results

Transrectal palpation revealed an impaction in the midabdominal area in all horses. Generalized distention of the small intestine was evident in 6 horses, whereas 4 horses were examined early in the course of the condition and did not have intestinal distention. Treatment consisted of intravenous administration of a balanced electrolyte solution, nasogastric intubation and siphonage, and administration of analgesics. Mineral oil was administered after gastric reflux had ceased. Mean time for resolution of ileal impaction was 11.7 hours.

Clinical Implications

Medical treatment may be a viable alternative for horses that cannot have surgery, provided persistent signs of severe pain or progressive gaseous distention of the small intestine are not features of the condition. Improvement of cardiovascular status, reduction in signs of abdominal pain, decrease in distention of loops of small intestine during repeated transrectal examination, softening of the impaction, and decreases in amounts of gastric reflux were indicative of a response to medical treatment. (J Am Vet Med Assoc 1996;208:898–900)

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in Journal of the American Veterinary Medical Association

Abstract

OBJECTIVE To report the outcomes of horses with suspected nephrosplenic entrapment (NSE) of the large colon treated by IV phenylephrine administration and exercise with and without trocarization (ie, medical management).

DESIGN Retrospective, observational study.

ANIMALS 134 horses.

PROCEDURES Electronic medical records were searched to identify horses that underwent medical management for suspected NSE at a veterinary teaching hospital between 1995 and 2014. Demographic information, physical and ultrasonographic examination findings, treatment information (including the number of times the treatment was performed and patient response), surgical findings if applicable, complications, and patient outcome were recorded. Descriptive statistics were reported.

RESULTS 72 horses had suspected NSE that resolved with medical treatment; 59 of 62 horses underwent laparotomy when medical management failed, and 3 were euthanized without surgery. Twenty-five of the 59 horses had confirmed NSE that was surgically corrected, and 34 had lesions other than or in addition to NSE. All horses that had surgically corrected NSE and 18 of 34 horses that had other lesions survived to hospital discharge. The odds of resolution of NSE with medical management were greater for horses that underwent ≤ 2 (vs > 2) treatments. The treatment success rate for horses that underwent trocarization was not greater than that for horses that did not have the procedure.

CONCLUSIONS AND CLINICAL RELEVANCE Suspected NSE resolved with the described medical management for most horses. However, results indicated the potential for misdiagnosis was high. Timely surgical intervention is recommended for horses that fail to respond to medical treatment.

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in Journal of the American Veterinary Medical Association

Abstract

Objective

To evaluate the ability of hyaluronic acid (HA), with and without transforming growth factor β (TGF-β), to stabilize the catabolic processes associated with atrophy of articular cartilage.

Animals

20 adult, skeletally normal, hound-type dogs.

Procedure

Dogs (20 to 30 kg) were randomly assigned to 1 of 5 groups. One group served as untreated controls. Bivalve casts were placed on the left hind limbs of the remaining 16 dogs to limit weightbearing and motion of the limb for 92 days. One group served as the cast control. Beginning on day 56, 3 groups received aseptic intra-articular injections in the left stifles of either 5 mg of HA or 5 mg of HA containing either 20 or 50 μg of TGF-β. Intra-articular injections were repeated at 4-day intervals until the end of the study. On day 92, stifles were harvested at necropsy. Medial femoral condyles were histologically processed, and the articular cartilage was stained for the presence of proteoglycans, stromelysin, tumor necrosis factor (TNF) α, and TNF receptors (p55 and p75).

Results

Decreased metachromasia was evident in the cartilage matrix of all cast groups, with the smallest decrease in the HA-treated group. Stromelysin was immunolocalized in articular cartilage of the cast (left) limbs of cast control and both HA/TGF-β-treated groups. TNF-α was localized in articular cartilage of all cast (left) and right limbs, except those of the HA-treated group. Receptors for TNF were observed in both limbs of untreated control and cast control groups and cast limbs of HA/TGF-β-treated groups. The receptors were not localized in the right limbs of the HA with or without TGF-β-treated groups. TGF-β did not decrease stromelysin or TNF-α or receptors at the doses used.

Conclusions

HA may mediate a chondrostabilizing influence on articular cartilage by down-regulating TNF-α. Importantly, HA appeared to exert its inhibitory influence on TNF-α, as well as stromelysin and TNF receptors, on a systemic basis.

Clinical Relevance

Results provide insight into the mode of action of HA as a therapeutic agent for arthritis and its stabilizing influence on cartilage metabolism. (Am J Vet Res 1996;57:1488-1496)

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in American Journal of Veterinary Research

Abstract

Objective—To evaluate the pharmacokinetic-pharmacodynamic parameters of enrofloxacin and a low dose of amikacin administered via regional IV limb perfusion (RILP) in standing horses.

Animals—14 adult horses.

Procedures—Standing horses (7 horses/group) received either enrofloxacin (1.5 mg/kg) or amikacin (250 mg) via RILP (involving tourniquet application) in 1 forelimb. Samples of interstitial fluid (collected via implanted capillary ultrafiltration devices) from the bone marrow (BMIF) of the third metacarpal bone and overlying subcutaneous tissues (STIF), blood, and synovial fluid of the radiocarpal joint were collected prior to (time 0) and at intervals after tourniquet release for determination of drug concentrations. For pharmacokinetic-pharmacodynamic analyses, minimum inhibitory concentrations (MICs) of 16 μg/mL (amikacin) and 0.5 μg/mL (enrofloxacin) were applied.

Results—After RILP with enrofloxacin, 3 horses developed vasculitis. The highest synovial fluid concentrations of enrofloxacin and amikacin were detected at time 0; median values (range) were 13.22 μg/mL (0.254 to 167.9 μg/mL) and 26.2 μg/mL (5.78 to 50.0 μg/mL), respectively. Enrofloxacin concentrations exceeded MIC for approximately 24 hours in STIF and synovial fluid and for 36 hours in BMIF. After perfusion of amikacin, concentrations greater than the MIC were not detected in any samples. Effective therapeutic concentrations of enrofloxacin were attained in all samples.

Conclusions and Clinical Relevance—In horses with orthopedic infections, RILP of enrofloxacin (1.5 mg/kg) should be considered as a treatment option. However, care must be taken during administration. A dose of amikacin > 250 mg is recommended to attain effective tissue concentrations via RILP in standing horses.

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in American Journal of Veterinary Research