Postanesthetic Pulmonary Edema In an Arab Stallion

A six-year-old arabian stallion was admitted to The Ohio State University Veterinary Hospital for evaluation and repair of a comminuted fracture of the second phalanx. The horse developed impaired arterial oxygenation during surgey and pulmonary edema post-operatively. We postulate that impaired arterial oxygenation resulted from atelectasis of the dependent lung during annesthesia, and the pulmonary edema occurred following re-expansion of the atelectatic of the initiating cause of the edema, removal of excess lung water from the alveoli, and restoration of normal arterial oxygenation. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. The horse was fully recovered within 12 hours of initiation of clinical signs of respiratory compromise. This report describes re-expansion pulmonary edema due to reperfusion injury in a horse, treatment of the condition, and a possible explanation of the pathogenesis of this pulmonary pathology.     

Pharmacokinetic and Phase I Evaluation of Carboplatin in Dogs

Thirty dogs with spontaneously occurring malignant neoplasms were treated monthly with carboplatin (CBDCA) given as a 30-minute intravenous infusion in a dose escalation study. Twenty-eight dogs were considered evaluable for toxicity. The maximally tolerated dose of CBDCA was conceptually defined as that dose, determined by logistic regression analyses of toxicity data, resulting in a 50% incidence of moderate toxicity (MOD₅₀) or a 5% incidence of severe toxicity (SEV₅). Each designated maximally tolerated dose was calculated for the first course of treatment only and for the first and second courses of treatment combined to estimate cumulative drug toxicity. The MOD₅₀ and SEV₅ for the first treatment course were 340 and 278 mg/M², respectively. MOD₅₀ and SEV₅ values for the first plus second treatment courses were 327 and 231 mg/M², respectively. The nadir of neutrophil and platelet counts occurred approximately 14 days after treatment. The mean neutrophil and platelet values for all dogs experiencing myelosuppression during the first two treatment courses were 1541/μL and 62,600/μL, respectively. Nonparametric pharmacokinetic analysis of plasma CBDCA values suggested that half-life (T_1/2), area-under-the-curve and total body clearance (CL_b) were not dose dependent. Volume of distribution (VD_ss) significantly increased with dose only between 100 and 150 mg/M², not between 150 and 300 mg/M². Dose-independent serum CBDCA pharmacokinetic disposition indicates that detailed investigation of tissue CBDCA distribution would be warranted and may identify novel dosing strategies that could improve the therapeutic index of CBDCA by minimizing toxicity. (Journal of Veterinary Internal Medicine 1993; 7:235–240. Copyright © 1993 by the American College of Veterinary Internal Medicine.)     

A Comparison of Two Methods of Partial Pancreatectomy in the Dog

Partial pancreatectomy was performed in 9 dogs by dissection and ligation of the pancreatic ductule and blood vessels, and in 10 dogs by a suture fracture technique. The dogs were evaluated for detrimental effects by (1) monitoring clinical signs and serum amylase and lipase activities and (2) examining the excision sites grossly and histologically at necropsy. There were no clinically apparent detrimental effects with either technique. The suture fracture technique evoked more histologic inflammation than the dissection and ligation technique.     

Evaluation of the Tibia as a Source of Autogenous Cancellous Bone in the Horse

A 1 cm defect was created in the proximal medial cortex of 12 tibiae, cancellous bone was removed from the site, and the bones were fractured by loading in torsion. The fractures did not occur through the donor sites and the fracture patterns and loads to fracture were similar for the treated tibiae and their untreated mates. Cancellous bone was harvested from the proximal medial aspect of both tibiae in nine adult horses. The soft tissue wounds were monitored for more than 10 days in seven horses and healing of the osseous defects was evaluated radiographically at regular intervals to month 6 in two horses. The site provided convenient access with the horses in lateral or dorsal recumbency, the anatomic landmarks were reliable, and the surgical procedure was simple and short. Complications occurred in only three incisions.     

Long-Term Follow-up of Partial Limb Amputation in 13 Horses

Thirteen cases of partial limb amputation in horses were reviewed. Nine horses (69%) survived 18 to 111 months (mean, 41 months). Four unsuccessfully treated horses were euthanatized within 21 days of surgery. The horses' ages at amputation were 4 to 13 years (mean, 7.3 years). There was no predilection for the left or right limb nor for fore or hind limb involvement. Osteomyelitis in six horses (46%) was the most common cause for amputation. Severe, open, comminuted fractures of the third metacarpal bone that were impossible to stabilize by any currently available technique in four horses (31%) were the second most common cause for amputation. One gelding was salvaged because of his sentimental value, two horses were used as breeding stallions, and six were broodmares. One stallion lived 30 months, completed two breeding seasons, and started a third. The other stallion began breeding, but became sterile. Three of the mares have produced five foals. One mare died while in foal. One mare aborted near-term twin fetuses and died of uterine hemorrhage. One mare aborted twice before the femoral head ligament on the contralateral limb ruptured, and she was euthanatized.     

Clinical Evaluation of Three Surgical Methods for Treatment of Caudal Cervical Spondylomyelopathy of Dogs

Sixty-four dogs with caudal cervical spondylomyelopathy (CCSM) caused by chronic degenerative disc disease were treated with ventral decompression (n = 20), linear traction and interbody screw stabilization (n = 7), or linear traction and plastic plate stabilization (n = 37). Interbody screw stabilization was ineffective in treating CCSM because of an unacceptably high rate of implant failures. Ventral decompression or linear traction and plastic plate stabilization were effective in the treatment of most patients with mild to moderate neurologic deficits (neck pain, paraparesis, or ambulatory tetraparesis). Although these techniques were also used successfully in some patients with severe neurologic deficits (weakly ambulatory tetraparesis or nonambulatory tetraparesis), variable success rates and prolonged postoperative recovery periods were noted.     

Treatment of Humeroulnar Subluxation with a Dynamic Proximal Ulnar Osteotomy A Review of 13 Cases

Humeroulnar subluxation was treated surgically in 13 dogs with 18 affected elbows using a proximal osteotomy of the ulna that allowed the ulna to elongate dynamically. Distal humeroulnar subluxation was secondary to premature closure of the distal ulnar physis in 16 elbows. One distal subluxation was secondary to a radioulnar synostosis, and one proximal subluxation developed after premature closure of the distal radial physis. The mean follow-up time was 22 months. Twenty-eight percent of the elbows were judged to have excellent results, 22% good results, 50% fair results, and none was judged to have a poor outcome. The presenting lameness grade and the severity of preoperative and postoperative humeroulnar subluxation had significant correlations with the prognosis. Associated orthopedic abnormalities and complications of concurrent surgical procedures affected the outcome in several dogs. Overall, the dynamic proximal ulnar osteotomy was a simple and effective technique for the treatment of uncomplicated humeroulnar subluxation.     

Arthroscopic Treatment of Osteochondritis Dissecans in the Canine Shoulder

Twenty-three shoulders of 21 dogs were treated arthroscopically for osteochondritis dissecans (OCD). Thirteen dogs had bilateral lesions detectable radiographically; however, only two dogs had arthroscopic surgery on both shoulders. Arthroscopic procedures included removal of the osteochondral flap, curettage of the subchondral defect, and partial synovectomy. Fourteen dogs were using the treated limb within 1 day and eight dogs within 2 days, although some lameness may have persisted for several weeks. Force plate evaluation was effective for comparison of preoperative and postoperative mean peak force/body weight (PF/BW) values. Improvement was detected objectively in 9 of the 10 dogs returned for postoperative force plate analysis. All owners were satisfied with the cosmetic results and the rapid return to function.     

Significance of the Heineke-Mikulicz Pyloroplasty in the Treatment of Gastric Dilatation-Volvulus A Prospective Clinical Study

Twenty-six dogs with gastric dilatation-volvulus (GDV) were stabilized medically, followed by tube gastrostomy and gastropexy. In 13 dogs, a Heineke-Mikulicz pyloroplasty was also performed. Complications and recurrences were monitored during the immediate postoperative period and for 5 to 31 months thereafter. Barium gastrograms and contrast radiographs of the stomach were evaluated at week 1 and months 5 to 31. Significantly fewer dogs without pyloroplasty had complications during the immediate postoperative period. There were no differences in the long-term complication rates. Radiographic evaluations of the width of the pylorus, the size of the stomach, and the rate of gastric emptying showed no differences between dogs with and without pyloroplasty at any evaluation period. The Heineke-Mikulicz pyloroplasty increased the immediate postoperative complication rate after surgical fixation of the stomach for the treatment of GDV. It did not appear to influence the long-term outcome of the surgical treatment of this disease. The Heineke-Mikulicz pyloroplasty is not recommended in the treatment of GDV unless pyloric outflow obstruction can be demonstrated.     

CLINICAL USE OF 99mTC-MDP SCINTIGRAPHY IN THE EQUINE MANDIBLE AND MAXILLA

^99mTc-methylene diphosphonate (MDP) radionuclide imaging examinations were done in four horses having clinical evidence of skull trauma or infection. Radiographs were made of each horse prior to scintigraphy. Four case histories are presented. In each instance, scintigraphy provided complementary information to that obtainable through radiography, which aided in accurately localizing and characterizing the site and extent of abnormalities, and which proved particularly valuable as an aid for therapeutic planning.