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  • Author or Editor: Geoffrey K. Saunders x
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in Journal of the American Veterinary Medical Association
in Journal of the American Veterinary Medical Association

Summary

We determined whether administration of cisplatin in hypertonic saline solution would prevent significant decrease in renal function, as measured by exogenous creatinine clearance, in healthy dogs. A single dose of cisplatin (70 mg/m2 of body surface) was mixed in 3% saline solution and was infused IV (6.5 ml/kg of body weight) over a 20-minute period to 6 healthy dogs. Exogenous creatinine clearance was determined prior to treatment of dogs with cisplatin and again on days 3 and 21 after administration of cisplatin. All 6 dogs vomited at least once within 12 hours of treatment with cisplatin; however, clinically important changes in appetite, body weight, or hydration status were not apparent during the 21-day study. Although mean values for exogenous creatinine clearance decreased from baseline on days 3 and 21, changes were not significantly different. Renal histologic lesions included mild, chronic, lympho-plasmacytic interstitial nephritis in 5 dogs, and presumably, were unrelated to treatment with cisplatin. Mild renal tubular atrophy (n = 2) and tubular necrosis (n = 1) may have developed secondary to treatment with cisplatin. Results of this study indicated that administration of a single dose of cisplatin in 3% saline solution to healthy dogs was not associated with significant decrease in glomerular filtration rate. This is a convenient protocol for administering cisplatin; however, additional study is required before it can be recommended for clinical patients, especially those with preexisting renal disease or those receiving multiple doses of cisplatin.

Free access
in American Journal of Veterinary Research

SUMMARY

Corticocancellous bone graft was obtained from the caudoventral portion of the mandible of 8 dogs. The recipient site was an alveolar jugal and alveolar defect from vital root amputation of the mesiobuccal root of the maxillary fourth premolar. Anatomic observations of 20 canine cadavers indicated that guidelines for harvesting bone from the caudoventral portion of the mandible of dogs were the mesial aspect of the masseteric fossa, the distal aspect of the roots of the first mandibular molar, and the ventral aspect of the mandibular canal. The mean weight of corticocancellous bone harvested was 0.4 ± 0.1 g. Harvested corticocancellous bone was adequate to fill recipient sites measuring a mean volume of 105.0 ± 28.5 mm3. Histologic evaluation of the recipient site revealed progressive osseous integration of the bone-graft site during a mean follow-up period of 3.5 ± 1.9 months. There was normal bone healing of the donor site without adverse effects on the mandibular molars or neurovascular structures of the mandibular canal. Vital amputation sites receiving silver amalgam had evidence of plasmacytic/lymphocytic inflammation associated with residual silver amalgam in the bone-graft area. The caudoventral portion of the mandible may be used as a donor site for autogenous corticocancellous bone in periodontal surgery of dogs.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To determine whether the prostaglandin E1 analogue, misoprostol, could preserve renal function in dogs receiving nephrotoxic doses of gentamicin.

Animals

12 (6/group) healthy sexually intact male dogs.

Procedure

All dogs were given high doses of gentamicin (10 mg/kg of body weight, IV, q 8 h, for 8 consecutive days). Six dogs (treatment group) received misoprostol (3 μg/kg, PO, q 8 h for the duration of the study) and 6 dogs (control group) received vehicle (1 capsule, PO, q 8 h). Renal function was assessed before treatment (day 0) and on days 3, 6, 9, and 11 after initiation of treatment by measurement of serum biochemical variables, urine specific gravity, and exogenous creatinine clearance. Serum electrolyte and protein concentrations and presence of proteinuria, glycosuria, and cylindruria were also determined. At the end of the study, renal histopathologic changes were evaluated.

Results

Dogs receiving misoprostol had significant reduction in exogenous creatinine clearance with time, compared with dogs receiving vehicle (P = 0.0264). Dogs receiving misoprostol tended to develop more severe azotemia, hyperphosphatemia, and renal histopathologic changes; however, results were not significantly different between groups.

Conclusion

Misoprostol (3 μg/kg, PO, q 8 h) did not preserve renal function and may have exacerbated gentamicin-induced nephrotoxicosis in this group of dogs.

Clinical Relevance

Supplementation of vasodilatory prostanoids may exacerbate renal dysfunction in dogs receiving high doses of gentamicin. (Am J Vet Res 1998;59:1048–1054)

Free access
in American Journal of Veterinary Research

SUMMARY

Eighteen healthy dogs were allotted to 3 groups (n = 6 dogs each). All dogs were evaluated at the beginning of the study by complete physical examination; total and differential WBC counts; serum biochemical analysis (alanine transaminase and alkaline phosphatase activities and bilirubin and albumin concentrations); sulfobromophthalein excretion, ammonia tolerance, and glucagon response testing; portal and intraparenchymal pressure determinations; operative mesenteric portography; and histologic assessment of hepatic biopsy specimens.

The left hepatic vein was ligated completely in dogs of groups 1 and 2. Group-3 (control) dogs had a ligature placed loosely around the left hepatic vein. Dogs of groups 1 and 3 were reevaluated 24 hours after surgery by use of the aforementioned hematologic and biochemical tests. Group-1 dogs were reevaluated by use of portal and intraparenchymal pressure determinations, jejunal vein portography, and complete necropsy at 48 hours after surgery. At 4 weeks after surgery, dogs of groups 2 and 3 were reevaluated by use of all aforementioned tests.

Results indicated transient hepatic congestion, which resolved by the fourth postoperative week. Longstanding effect on hepatic structure, circulation, or function was not found. We concluded that left hepatic vein ligation in clinically normal dogs does not cause severe or permanent liver damage.

Free access
in American Journal of Veterinary Research

Abstract

Objective

To determine the effects of autologous fibrinogen (AF) and absorbable barrier membrane (ABM) on periodontal healing of canine experimental grade-III furcation defects.

Animals

18 conditioned, laboratory-source, adult Beagles.

Procedure

Defects were developed bilaterally at the second and fourth premolars and maintained for 12 weeks. Defects were treated with AF, ABM, AF and ABM, or debridement. Digital subtraction radiography, histologic evaluation, and histomorphometric analysis of defect healing was done at 1, 3, and 6 months after treatment to determine percentage increases in bone volume, height, area, and length of periodontal regeneration along the perimeter of the defect.

Results

Comparison of defects at post-treatment intervals indicated significantly greater healing of debridement and AF-treated defects, compared with ABM-treated defects at 3 months; however, by 6 months, there were no significant differences in defect healing for all histomorphometric variables. Defects treated with ABM were associated with significantly less root ankylosis than other treatments. Defects treated with debridement had significantly greater increases in bone volume at 6 months after treatment, compared with groups treated with ABM. There was a significant correlation between regenerated bone area, bone volume, and periodontal regeneration for all treatments at 3 and 6 months after treatment.

Conclusion and Clinical Relevance

Use of AF and ABM did not enhance the amount of periodontal healing, compared with debridement only. The ABM-treated defects were essentially devoid of root ankylosis. Grade-III furcation defects may respond equally well to conservative periodontal surgery or guided tissue regenerative techniques. The prevention of root ankylosis is a substantial benefit favoring this latter method of treatment. (Am J Vet Res 1998;59:1329-1338)

Free access
in American Journal of Veterinary Research

Summary

Bilateral midbody hemimandibular osteotomies were performed between premolars 3 and 4 in 18 adult dogs. Hemimandibles were repaired by use of monocortically applied bone plates (n = 6), an interdental fixator composed of an Erich arch bar and acrylic (n = 6), or a type I external skeletal fixator (n = 6). At the immediate postoperative evaluation, hemimandibles stabilized with interdental fixators had an osteotomy gap distance (mean ± SEM, 1.6 ± 0.2 mm) that was significantly (P < 0.05) greater than for hemimandibles stabilized with external skeletal fixators (1.2 ± 0.3 mm). Osteotomy gap distance of hemimandibles stabilized with external skeletal fixators (1.5 ± 0.2 mm) was significantly (P < 0.05) greater at weeks 4 (1.1 ± 0.2 mm) and 8 (0.8 ± 0.3 mm) after surgery than the osteotomy gap distance of hemimandibles stabilized by application of bone plates. By week 16, significant differences in osteotomy gap distance were not detected between groups. Immediately after surgery, mandibular alignment measurements were not significantly different for dogs with bone plates (0.3 ± 0.1 mm), interdental fixators (0.3 ± 0.1 mm), and external skeletal fixators (0.9 ± 0.5 mm). Mandibular alignment scores were not significantly different between treatment groups during the remaining postoperative period. Occlusal measurements were not significantly different between evaluations performed before surgery and 16 weeks after surgery, regardless of treatment group. Radiographic evidence of healing in hemimandibles stabilized with external skeletal fixators was significantly (P < 0.05) less at 4 and 8 weeks, compared with hemimandibles stabilized with bone plates and interdental fixators; however, radiographic evidence of bone healing was not significantly different between fixation groups at 16 weeks. Radiographic evidence of implant loosening was seen in 1 of 12 (8%) hemimandibles receiving bone plates, 1 of 12 (8%) hemimandibles receiving interdental fixators, and 4 of 12 (33%) hemimandibles receiving external skeletal fixators. Periosteotomy callus was radiographically evident in 11 of 18 (61%) hemimandibles at 4 and 8 weeks only, but significant differences in periosteotomy callus surface area were not detected between groups. Of 24 hemimandibles stabilized with interdental and external skeletal fixators, 22 (92%) had callus formation that progressively matured into trabecular bone by 16 weeks. At 4 weeks, bone healing characterization scores of hemimandibles stabilized with bone plates were significantly (P < 0.05) less than (ie, had greater stability) bone healing characterization scores of hemimandibles stabilized with interdental and external skeletal fixators, but at 8 and 16 weeks, bone healing characterization scores between treatment groups were not significantly different. Histopathologic or radiographic evaluation did not reveal evidence of pulp disease or pathologic changes of teeth, which would have been associated with root resection at the osteotomy site, application of acrylic to the crown surface, or placement of external fixator pins and cortical screws. On the basis of the fact that the dogs appeared clinically normal and were able to masticate, analgesics were discontinued by 24 hours after surgery. Analysis of data indicated that an interdental fixator composed of an Erich arch bar and acrylic may be a viable method for fracture repair of mandibles.

Free access
in Journal of the American Veterinary Medical Association