Treatment of chronic pleural effusion with pleuroperitoneal shunts in dogs: 14 cases (1985-1999).

OBJECTIVE: To describe complications and outcome associated with chronic nonseptic pleural effusion treated with pleuroperitoneal shunts in dogs. DESIGN: Retrospective study. ANIMALS: 14 dogs. PROCEDURE: Medical records at 4 veterinary schools were examined to identify dogs with chronic nonseptic pleural effusion that were treated by use of a pleuroperitoneal shunt between 1985 and 1999. Signalment, history, physical examination and laboratory findings, cause and type of pleural effusion, medical and surgical treatments, complications, and outcome were reviewed. RESULTS: 10 of 14 dogs had idiopathic chylothorax, and 4 had an identified disease. All but 1 dog with idiopathic chylothorax and 1 dog with chylothorax from a heart base tumor had unsuccessful thoracic duct ligation prior to pump placement. No intraoperative complications developed during shunt placement. Short-term complications developed in 7 of 13 dogs, necessitating shunt removal in 2 dogs and euthanasia in 1. Eight of 11 dogs with long-term follow-up developed complications; the overall mean survival time and the interval in which dogs remained free of clinical signs of pleural effusion were 27 months (range, 1 to 108 months) and 20 months (range, 0.5 to 108 months), respectively. CONCLUSIONS AND CLINICAL RELEVANCE: Pleuroperitoneal shunts can effectively palliate clinical signs associated with intractable pleural effusion in dogs. Numerous short- and long-term complications related to the shunt should be expected. Most complications can be successfully managed, but even when shunts are functional some treatments fail because of severe abdominal distension or massive pleural fluid production that overwhelms the functional capacity of the shunt.

Ureteral obstruction after ureteroneocystostomy in dogs assessed by technetium TC 99m diethylenetriamine pentaacetic acid (DTPA) scintigraphy.

OBJECTIVE: To use technetium Tc 99m diethylenetriamine pentaacetic acid (99mTc-DTPA) renal scintigraphy to monitor ureteral obstruction after ureteroneocystostomy in a canine model of partial ureteral obstruction. STUDY DESIGN: Experimental study. ANIMALS: Eight normal adult dogs. METHODS: Partial ureteral obstruction was created in 8 dogs by incomplete ligation of the terminal right ureter. Two weeks later, ureteroneocystostomy was performed in 7 dogs with unilateral partial ureteral obstruction and in 1 dog that had developed bilateral partial ureteral obstruction. 99mTc-DTPA scintigraphy was performed intermittently for 2 weeks after ureteroneocystostomy. Renal transit time of each kidney, as assessed by the time to maximal uptake (time of peak), and glomerular filtration rate, as assessed by percentage of kidney uptake of the radiopharmaceutical between 1 and 3 minutes, were estimated. Comparison between affected and nonaffected kidneys was performed with the Wilcoxon rank sum test. RESULTS: Unilateral partial ureteral obstruction was induced successfully in 7 dogs. In 1 dog, bilateral partial obstruction was induced inadvertently. After ureteroneocystostomy, percentage of kidney uptake of 99mTc-DTPA was low in 4 affected kidneys. The uptake returned to within normal limits in 2 of the kidneys during the observation period. The time activity curve had a more rounded appearance or was increasing continuously for all affected kidneys. A significant increase in renal transit time was observed 2 and 4 days after ureteroneocystostomy. Transit time progressively returned to normal by 4 to 11 days for all affected kidneys except 1. CONCLUSION: Ureteroneocystostomy resulted in persistent partial ureteral obstruction for 4 to 11 days as determined by 99mTc-DTPA scintigraphy. CLINICAL RELEVANCE: 99mTc-DTPA scintigraphy may be a useful procedure for monitoring renal function and ureteral obstruction after ureteroneocystostomy. Persistent partial ureteral obstruction may be seen 1 to 2 weeks after ureteral reimplantation in dogs with previously existing dilated ureters.

Urethrotomy and urethrostomy in the dog.

An incision, or urethrotomy, is made into the urethral lumen to remove or relieve an obstruction temporarily. When permanent diversion of urine flow proximal to an obstructed, severely damaged, or diseased urethra is required, a urethrostomy is performed. Urethrostomy is also performed to diminish the risk of urethral obstruction due to recurrent urinary calculi that are not likely to be resolved with medical therapy. Whenever possible, to reduce the risk of urethral stricture or recurrent urinary tract infection, urethral surgery is avoided when an obstruction can be relieved by retrohydropropulsion or catheterization. Urethrotomy can be performed in the prescrotal or perineal regions depending on the level of the urethral obstruction. Although urethrostomy can be made in the perineal and antepubic positions, scrotal urethrostomy is the procedure of choice provided the lesion is distal to this area. Specific urethrotomy and urethrostomy procedures are described, including discussion about selection of the appropriate procedure for the urethral problem, patient stabilization considerations, general postoperative management, and risk of complications.

Radiotelemetry catheter implantation: surgical technique and results in cats.

Arterial blood pressure in cats can be measured by direct or indirect techniques. Most direct measurement techniques require sedation or anesthesia, which decreases blood pressure. The restraint and human intervention needed for indirect techniques cause blood pressure to increase. These limitations make the accurate assessment of blood pressure and the response to antihypertensive medications difficult to interpret. Radiotelemetry allows for direct measurement of the arterial blood pressure and heart rate without sedation, anesthesia, or animal handling during measurement. A surgical technique for the placement of radiotelemetry catheters and the complications associated with the technique have not been described in cats. Our purpose is to provide a detailed description of the placement of the modified implant model TA11PA-C40 (Data Sciences International), with accompanying illustrations, and to discuss complications associated with the procedure. Radiotelemetry catheters were surgically placed in the left femoral artery of 12 cats. The surgical procedure was completed within 50 min, and no surgical complications occurred in any cat. The radiotelemetry catheters were used for an average of 6.5 weeks (range, 5.5 to 9.5 weeks). This technique allows for long-term monitoring of ambulatory blood pressure and heart rate in the research setting. This methodology is especially useful for studies of the pathophysiology of hypertension and assessment of the efficacy of antihypertensive medications.

Effect of partial ureteral obstruction on results of renal scintigraphy in dogs.

OBJECTIVE: To use scintigraphy to determine the effects of partial ureteral obstruction on renal transit time and induction of diuresis in dogs. ANIMALS: 8 adult dogs. PROCEDURE: Scintigraphy was performed, using technetium Tc 99m diethylenetriaminepentacetic acid (Tc 99m-DTPA), before and within 2 weeks after surgical induction of unilateral partial ureteral obstruction. Time of peak (TOP) for the parenchyma (pTOP) and whole kidney (wTOP) and mean-transit time (MTT) for the parenchyma (pMTT) and whole kidney (wMTT) were determined by evaluation of renal time-activity curves before and after deconvolution analysis. Percentage uptake for each kidney between 1 and 3 minutes after injection of Tc 99m-DTPA was determined and used to indicate glomerular filtration rate. The effect of diuresis was determined by measuring the slope of decrease in activity after i.v. administration of furosemide. Obstruction was documented by direct inspection of the ureter. RESULTS: There was a concomitant increase in pTOP, wTOP, pMTT, and wMTT of the kidney with the partially obstructed ureter in all dogs at various times between 2 and 9 days after surgery. Concurrently, renal time-activity curves changed shape. Percentage renal uptake of the affected kidney was decreased in 2 dogs. Response to furosemide injection was inconsistent for kidneys before surgery and for kidneys with obstructed and nonobstructed ureters after surgery. CONCLUSIONS AND CLINICAL RELEVANCE: Scintigraphy may be a useful procedure for the evaluation of renal function in dogs with ureteral obstruction. Induction of diuresis appears to be of little value for differentiating renal function in dogs with obstructed and nonobstructed ureters.

Comparison of a continuous suture pattern with a simple interrupted pattern for enteric closure in dogs and cats: 83 cases (1991-1997).

OBJECTIVE: To describe and compare a simple continuous suture pattern with a simple interrupted pattern for enterotomy closure or end-to-end intestinal anastomosis. DESIGN: Retrospective study. ANIMALS: 58 dogs and 25 cats that underwent enterotomy or intestinal resection and anastomosis. PROCEDURE: Signalment, surgical procedure, suture pattern, suture material, confirmation of dehiscence, and follow-up were reviewed. Groups were compared by procedure (anastomosis or enterotomy) and by suture pattern. RESULTS: 57 animals underwent continuous closure; 26 had interrupted closure. Only polydioxanone or polypropylene suture materials were used. Overall, 81 (98%) animals had no signs of intestinal dehiscence and survived > 2 weeks. Two animals had confirmed dehiscence after foreign body removal, 1 of 57 (2%) after continuous closure, and 1 of 26 (4%) after interrupted closure. CLINICAL IMPLICATIONS: The simple continuous closure pattern is an acceptable alternative to simple interrupted closure for small intestinal anastomosis or enterotomy closure.

Effect of enalapril on blood pressure, renal function, and the renin-angiotensin-aldosterone system in cats with autosomal dominant polycystic kidney disease.

OBJECTIVE: To evaluate blood pressure, renal function, and the renin-angiotensin-aldosterone system (RAAS) in cats with autosomal dominant polycystic kidney disease (ADPKD) and to assess the effect of enalapril on these variables. ANIMALS: 6 cats with ADPKD and 6 age-matched healthy cats. PROCEDURE: To measure blood pressure and heart rate, a radiotelemetry catheter was placed in the left femoral artery of each cat. Baseline data collection included 24-hour blood pressure, heart rate, and motor activity. Blood was then collected for analysis of RAAS status and renal function. Enalapril (0.5 mg/kg of body weight, p.o., q 24 h) was administered for 1 week, and data collection was repeated. RESULTS: Differences in baseline blood pressure, heart rate, motor activity, RAAS status, and renal function were not detected between cats with ADPKD and control cats. Hypertension was not documented in cats with ADPKD. Blood pressure was significantly reduced for 15 to 17 hours after treatment with enalapril in both groups. Administration of enalapril also resulted in significant increases in plasma renin activity and significant decreases in angiotensin converting enzyme activity and atrial natriuretic peptide concentration but only minimal changes in glomerular filtration rate and effective renal plasma flow in both groups of cats. CONCLUSIONS AND CLINICAL RELEVANCE: Although hypertension is common in humans with ADPKD, cats with ADPKD were normotensive. Treatment with enalapril (0.5 mg/kg, p.o., q 24 h) significantly reduced blood pressure in normotensive healthy cats and cats with ADPKD, and resulted in predictable changes in RAAS enzyme activities and hormone concentrations. Enalapril had minimal effects on renal function.

Gallbladder perforation associated with cholelithiasis and cholecystitis in a dog.

A four-year-old female Japanese akita was admitted with icterus, ascites and chronically elevated serum bilirubin and liver enzymes. Abdominal ultrasonography revealed a diffusely thickened, hyperechoic gallbladder wall with a focal defect, hepatic lymphadenopathy and a large volume of anechoic fluid within the peritoneal space. Diagnosis of biliary tract rupture with bile peritonitis was based on the findings of bile and suppurative exudate in peritoneal aspirates. A perforated gallbladder and cholelithiasis were found on exploratory celiotomy, while histopathology revealed chronic suppurative cholecystitis. The dog recovered uneventfully after cholecystectomy. Although rare, the triad of cholelithiasis, cholecystitis and gallbladder perforation should be considered after detection of one of these conditions.

Incomplete urethral duplication with cyst formation in a dog.

Incomplete urethral duplication with cyst formation was diagnosed in a dog that had soft, fluctuant, subcutaneous swellings in the ventral perineal and penile areas and a history of nocturia and incontinence during recumbency that were unresponsive to treatment with antibiotics. Retrograde urethrocystography, voiding urethrography, double-contrast cystography, radiography after direct administration of contrast medium into cystic structures, and excretory urography were performed to evaluate the urinary tract. Communication between the cysts and the urethra was demonstrated radiographically only after intralesional injection of contrast medium. Nocturia and incontinence resolved after surgical removal of the urethral duplication and cysts. The dog was clinically normal 1 year after surgery.

Porcelain gallbladder associated with primary biliary adenocarcinoma in a dog.

A 9-year-old spayed female Poodle was admitted because of vomiting of 3 weeks' duration, lethargy, and anorexia. Palpation of the cranial portion of the abdomen elicited signs of pain. Principal laboratory abnormalities included mild segmented neutrophilia, lymphopenia, high serum alanine aminotransferase, aspartate aminotransferase, and alkaline phosphatase activities, and hyperbilirubinemia. Radiography revealed foamy appearing areas of mineral opacity in the region of the gallbladder. Ultrasonographically, a hyperechoic structure with acoustic shadowing was seen in the same region, and extrahepatic bile ducts were distended. Cholecystectomy was performed. The gallbladder wall felt thicker than normal and was bluish-white. Multiple choleliths were found in the gallbladder and extrahepatic bile ducts. Histologic examination revealed chronic proliferative lymphoplasmacytic cholecystitis with mineralization and a well-differentiated adenocarcinoma of the gallbladder neck. A diagnosis of porcelain gallbladder was made. The dog recovered without complications and was healthy 14 months after surgery. To our knowledge, porcelain gallbladder has not been reported in dogs. In human patients, it is defined as intramural mineralization of the gallbladder commonly associated with gallbladder neoplasia. Early recognition is important for appropriate surgical treatment.

Surgical treatment of dacryocystitis caused by cystic dilatation of the nasolacrimal system in three dogs.

A 4-year-old castrated male Golden Retriever was referred for evaluation of intermittent purulent discharge from the right eye of 4-months' duration. A radiolucent area in the maxillary bone was detected on examination of skull radiographs. Dacryocystorhinography revealed pooling of contrast material in the radiolucent area. A rhinotomy was performed, and a large opening between the cystic structure of the nasolacrimal system and the nasal cavity was created. Epiphora resolved after surgery and had not recurred by 9 months after surgery. Two other dogs had cystic structures of the nasolacrimal system and were treated surgically to allow drainage into the nasal cavity.

Traumatic separation of the annular cartilage from the external auditory meatus in a cat.

A 13-year-old cat was evaluated because of anorexia and otic discharge of 1 week's duration. A left head tilt and left facial nerve deficit were evident. Pink fleshy tissue was seen in the area where the tympanic membrane was expected during otoscopic examination. The left ear canal was laterally displaced from the skull on a rostrocaudal (open mouth) radiographic view, suggesting ear canal separation. During surgery, the annular cartilage was found to be separated from the external auditory meatus, and total ear canal ablation was performed. Complications did not develop, and facial nerve function returned 6 weeks after surgery. In previous reports, traumatic ear canal separation was diagnosed after trapped otic secretions formed abscesses or para-aural fistulas.

Simple continuous closure of canine scrotal urethrostomy: results in 20 cases.

Simple continuous closure of scrotal urethrostomy in 20 dogs is described. Mean duration of postoperative active bleeding and mean duration of bleeding only associated with urination were 0.2 day and 3.1 days, respectively. Long-term complications were minimal; intermittent urine scald (n = 2), recurrent urinary tract infections (n = 2), and recurrent obstruction due to struvite stones (n = 2) developed after surgery. All complications resolved with medical therapy (n = 4) or by cystotomy (n = 2). None of the dogs had complications due to wound dehiscence, stricture, incisional infections, self-mutilation, or incontinence. Follow-up ranged from two to 52 months (mean, 25.2 months). This technique is a viable alternative to previously reported closure methods.

Treatment of recurrent otitis media that developed after total ear canal ablation and lateral bulla osteotomy in dogs: nine cases (1986-1994).

OBJECTIVE: To assess clinical findings and long-term outcome of dogs treated for recurrent middle ear infection that developed after total ear canal ablation and lateral bulla osteotomy. DESIGN: Retrospective case series. ANIMALS: Of 94 dogs (142 ears) treated by means of total ear canal ablation and lateral bulla osteotomy for end-stage otitis, 9 developed recurrent middle ear infection. PROCEDURE: Information regarding treatment and outcome were retrieved from the medical records. RESULTS: Antibiotic treatment was attempted in 8 dogs, but failed to cure recurrent otitis media in 7 of 8 dogs. Seven dogs were treated by means of exploratory surgery, which consisted of ventral bulla osteotomy and tympanic curettage. One dog was cured, 1 developed another infection and was euthanatized, and the 5 remaining dogs developed another middle ear infection after the first exploratory surgery. Infection resolved after retained epithelium was removed from the tympanic cavity during a second exploratory surgery of the bulla in these 5 dogs. CLINICAL IMPLICATIONS: Antibiotic treatment rarely is effective for resolving recurrent middle ear infection that develops after total ear canal ablation and lateral bulla osteotomy. Ventral bulla osteotomy and curettage can be a successful method of treatment, provided retained epithelium and debris are completely removed from the ear canal and tympanic cavity.

Progressive lymphangiectasis and recurrent chylothorax in a dog after thoracic duct ligation.

A 2-year-old Bernese Mountain Dog was examined to determine the cause of bilateral pleural effusion. Torsion was diagnosed, and a lobectomy of a lung lobe was performed. Chylothorax developed 12 days after lung lobectomy. Mesenteric lymphangiography revealed lymphangiectasis Lymphangiography immediately after surgical thoracic duct was completely obstructed, but chylothorax persisted after thoracic duct ligation. Lymphangiography was repeated 50 days after ligation of the thoracic duct and revealed multiple patent thoracic duct branches and progressive lymphangiectasis. A second attempt to ligate the thoracic duct caused the effusion to become serosanguineous. A pleuroperitoneal shunt with a manually operated pump chamber was used to remove the pleural effusion. Chylothorax was again detected 50 weeks after placement of shunt. Mesenteric lymphangiography revealed multiple patent thoracic duct branches and a lymphatic plexus that extended across the thoracic cavity.

Complications of indwelling, silastic central venous access catheters in dogs and cats.

The records of 35 dogs and two cats with Broviac-Cookea catheters implanted during a one-year period at The Ohio State University Veterinary Teaching Hospital (OSU-VTH) were reviewed for complications. In 36 patients, the catheters were used for daily anesthesia associated with cobalt radiotherapy, and in one dog the catheter was used for parenteral hyperalimentation. The catheters were in place for a mean of 16.7 days. Complications occurred in five patients and included infection or sepsis (n = 3), local abscess formation (n = 1), and local induration (n = 1); all the complications resolved with appropriate therapy. Broviac-Cooke catheters should be considered for use in dogs and cats requiring frequent blood sampling, repeated intravenous access, or in those for which routine venous access is difficult or impossible. The complication rate is minimal (13%) and is similar to that reported in studies of humans with indwelling, silastic catheters.

Histologic evaluation of tissue reactivity and absorption in response to a new synthetic fluorescent pigmented polypropylene suture material in rats.

The degree and type of tissue reactivity and the absorption of a new suture material was determined by implantation within rat gluteal muscles. Amount and type of tissue inflammatory reaction was compared among the new suture material, polypropylene, and coated polyamide. Histologic evaluation of the tissues in which sutures were implanted indicated that the new suture material, polypropylene, and coated polyamide had similar amounts and types of reaction at 30 days or less after implantation, but differed after 30 days. The new suture material and polypropylene had an inflammatory reaction zone measuring less than 25% of the high-power field after 60 days, but the coated polyamide still induced reaction greater than 45% of the field at 90 days. At 60 and 90 days after implantation, the new suture material and polypropylene induced a mature fibrous reaction; the reaction to coated polyamide was either immature fibrous or granulomatous, depending on whether there was rupture of the suture coat. There was no observable absorption of the new suture material at 90 days. This study indicated that the new suture material is nonabsorbable and is minimally reactive in rat muscle. The tissue reactions induced by this suture material are similar to those of polypropylene and significantly less than those induced by coated polyamide after 30 days following implantation.