A systematic review and meta-analysis of prevalence of complications after tracheal stenting in dogs.

BACKGROUND: Stenting has become popular to treat tracheal collapse in dogs, but complications might arise and negatively affect treatment outcome. OBJECTIVES: Determine the overall prevalence of complications of tracheal stenting in dogs. METHODS: A bibliographic search was performed of publications from 2000 to 2020. Studies were assessed for quality of evidence and measured prevalence of the 8 most commonly reported complications after tracheal stenting in dogs (stent fracture, stent migration, relapsing collapse, granuloma formation, tracheobronchial infections, and early, late, and clinically relevant late cough). Random effects meta-analyses were used to estimate pooled complications prevalence. RESULTS: Fifteen studies met inclusion criteria. Cough (early: 99%; 95% confidence interval [95% CI]: 95%-100%, late: 75%; 95% CI: 63%-85%, and clinically relevant: 52%; 95% CI: 42%-61%), tracheobronchial infections (24%; 95% CI: 14%-35%), and granulomas (20%; 95% CI: 11%-30%) were common after tracheal stenting. Stent fractures (12%; 95% CI: 5%-20%), relapsing collapse (10%; 95% CI: 5%-15%), and stent migration (5%; 95% CI: 1%-9%) were less frequent. Significant heterogeneity among studies was identified for the estimated prevalence of stent fracture, granulomas, infections, and late cough. CONCLUSIONS AND CLINICAL IMPORTANCE: Tracheal stenting in dogs is associated with a high risk of coughing and a moderate risk of tracheobronchial infections and granuloma formation. Because most complications will impact a dog's quality of life, owners must be informed that tracheal stenting is a second-line procedure that does not necessarily alleviate the need for medical treatment and frequent follow-up visits. Additional studies are warranted to identify the risk factors of these complications.

Combined cholecystotomy, retrograde hydropulsion, and choledochal stenting to treat extrahepatic biliary tract obstruction in 3 cats.

Extrahepatic biliary tract obstruction (EHBO) is uncommonly encountered in cats. Surgical treatment aims to decompress the biliary tract and insure bile duct patency. In veterinary medicine, cholecystotomy is not widely used in practice. The objective was to describe the use of cholecystotomy, retrograde hydropulsion of choleliths, and choledochal stenting to remove choleliths from the extrahepatic biliary tract back in the gallbladder. Three adult domestic shorthair cats were presented with anorexia, lethargy, and vomiting. Serum biochemistry revealed hyperbilirubinemia and increased hepatic enzymes. Abdominal ultrasonography showed evidence of EHBO requiring surgical intervention. Choleliths were localized in the proximal and middle portions of the common bile duct (CBD) in the first case, in the distal portion of the CBD and within the major duodenal papilla in the second case, and in the middle and distal portions of the CBD in the third case. Cholecystotomy was followed by retrograde hydropulsion of the choleliths into the gallbladder, after which choledochal stenting was performed. Complications were defined as major when requiring additional medical or surgical treatment, or minor when not. Three major complications were reported. In 2 cases, severe anemia requiring blood transfusion occurred 24 h postoperatively; in 1 case, EHBO recurrence was encountered 41 d postoperatively. All cats were discharged within 4 d following surgery. Two cats were still alive at 12 and 14 mo after surgery, respectively. In the last case, owners refused revision surgery and the cat was euthanized. Key clinical message: Cholecystotomy combined with retrograde hydropulsion of choleliths permitted removal of choleliths and decompression of the biliary tract in 3 cats. Major complications included severe anemia and EHBO recurrence.

Cholécystotomie combinée, hydropulsion rétrograde et pose de stent cholédocien pour traiter l'obstruction des voies biliaires extra-hépatiques chez 3 chats. Les obstructions biliaires extra-hépatiques (OBEH) sont peu fréquentes chez le chat. Le traitement chirurgical vise à lever l'obstruction et s'assurer de la perméabilité des voies biliaires. En médecine vétérinaire, la cholécystotomie est une technique peu pratiquée. L'objectif de ce rapport de cas était de décrire l'utilisation de la cholécystotomie, de l'hydropulsion rétrograde des cholélithes et d'une prothèse endoluminale cholédoquale (PEC) pour repousser les cholélithes présents dans les voies biliaires extrahépatiques dans la vésicule biliaire (VB).Trois chats européens adultes ont été présentés pour anorexie, léthargie et vomissements. La biochimie sérique a révélé une hyperbilirubinémie et une augmentation des enzymes hépatiques. L'échographie abdominale a mis en évidence une OBEH nécessitant une intervention chirurgicale. Les cholélithes étaient situés dans la portion proximale et moyenne du canal cholédoque pour le premier cas; dans la portion distale et la papille duodénale majeure dans le second cas; dans la portion moyenne et distale pour le troisième cas. Une cholécystotomie a été suivie d'une rétro-hydropulsion des cholélithes dans la VB, puis une PEC a été placée. Les complications ont été définies comme majeures lorsqu'elles nécessitaient un traitement médical ou chirurgical supplémentaire, ou mineures lorsqu'elles n'en nécessitaient pas.Trois complications majeures ont été rapportées : chez 2 cas, une anémie sévère a été observée 24 h après l'intervention, nécessitant une transfusion sanguine; chez un cas, une récidive d'obstruction biliaire a eu lieu à 41 jours postopératoire. Tous les patients sont sortis de l'hôpital dans les 4 jours suivant l'opération. Deux cas étaient encore en vie 12 et 14 mois après l'intervention. Pour le dernier cas, la seconde chirurgie a été refusée par les propriétaires et le chat a été euthanasié.Message clinique clé :La cholécystotomie combinée à l'hydropulsion rétrograde des cholélithes a permis le retrait de cholélithes obstructives (dont certaines distales) et la décompression du tractus biliaire chez 3 chats. Les complications majeures incluaient une anémie sévère et une récidive d'obstruction biliaire.(Traduit par les auteurs).

Placement of a subcutaneous ureteral bypass in a Miniature Pinscher with presumed xanthine urolithiasis as a result of allopurinol treatment.

INTRODUCTION: This case report describes the long-term success of a subcutaneous ureteral bypass device in a dog for treatment of a ureteral obstruction. The suspected xanthine urolithiasis was secondary to treatment with allopurinol for leishmaniasis. The dog presented initially with lethargy, anuria and abdominal pain. Mild azotemia was found on biochemical analysis and abdominal ultrasound revealed bilateral ureteral obstruction. A subcutaneous ureteral bypass was subsequently placed using a standard surgical technique. The dog recovered uneventfully and the azotemia resolved within days. Follow-up examinations were performed every trimester for over three years and no complications like obstruction of the bypass tubes, urinary tract infection or azotemia were recognized during this follow-up period. Allopurinol was replaced with domperidone as long-term treatment against Leishmaniasis which resulted in a mild increase of the leishmania serum antibody titer. The subcutaneous ureteral bypass placement was successful and safe in this dog and is a valuable alternative in cases of ureteral obstruction also in dogs.

INTRODUCTION: Ce rapport de cas décrit le succès à long terme d'une dérivation urétérale sous-cutanée chez un chien pour le traitement d'une obstruction urétérale. L'urolithiase xanthique suspectée était secondaire à un traitement à l'allopurinol contre la leishmaniose. Le chien a d'abord présenté une léthargie, une anurie et des douleurs abdominales. L'analyse biochimique a révélé une légère azotémie et l'échographie abdominale a révélé une obstruction urétérale bilatérale. Une dérivation urétérale sous-cutanée a été mise en place selon une technique chirurgicale standard. Le chien s'est rétabli sans incident et l'azotémie a disparu en quelques jours. Des examens de suivi ont été effectués tous les trimestres pendant plus de trois ans et aucune complication telle qu'une obstruction du tube de dérivation, une infection urinaire ou une azotémie n'a été constatée au cours de cette période de suivi. L'allopurinol a été remplacé par de la dompéridone dans le cadre d'un traitement à long terme contre la leishmaniose, ce qui a entraîné une légère augmentation du titre des anticorps sériques contre la leishmaniose. La mise en place d'une dérivation urétérale sous-cutanée s'est avérée efficace et sûre chez ce chien et constitue une alternative intéressante en cas d'obstruction urétérale, y compris chez les chiens.

Long-term outcome of permanent tracheostomy management in two brachycephalic dogs using a commercial and a three-dimensional-printed silicone stent.

OBJECTIVE: To report the long-term outcome of utilization of a silicone stent to support the management of a permanent tracheostomy. STUDY DESIGN: Short case series. ANIMALS: Two client-owned brachycephalic dogs. METHODS: Two brachycephalic dogs with stage III laryngeal collapse underwent permanent tracheostomy. After the tracheostomy had healed, a silicone stent was inserted to support the stoma and facilitate home care. One dog wore a commercially available silicone stent for the follow-up period of 2 years. For the dog in Case 2, a 3D-printed, medical-grade silicone stent with an increased length was designed, as the dog had developed skin sores from the commercial device. RESULTS: Both dogs tolerated the silicone stent well. Stent care was managed by the owners without need for assistance. They reported that the silicone stent facilitated cleaning of the stoma surroundings and that they felt an increased confidence in airway patency, as the device prevented the tracheal stoma from collapsing. In Case 1, tracheoscopy 1 year after first stent insertion revealed minimal visible changes to the tracheal stoma. In Case 2, the 3D printed silicone stent led to a remission of skin sores and the dog wore the device comfortably until succumbing to an unrelated disease 13 months later. CONCLUSION: The insertion of a silicone stent is a simple and cost-effective method to improve home care of dogs with permanent tracheostomy. Larger dogs, as in Case 2, may benefit from custom-designed 3D-printed stents.

Bilateral neoureterocystostomy with distal ureteral tapering in a dog with severe bilateral hydroureteronephrosis.

A 3.5-year-old intact male Labrador retriever was seen for hematuria. The results of clinical pathology tests were unremarkable. However, urinalysis revealed dark, cloudy, alkalotic, and isosthenuric urine containing red and white blood cells, epithelial cells, and struvite crystals. Severe bilateral enlargement of ureters and markedly enlarged kidneys were identified on abdominal radiographs. Computerized tomography revealed extensive bilateral hydroureteronephrosis with no definitive cause of obstruction. The dog underwent bilateral ureteral tapering with bilateral neoureterocystostomy and placement of temporary bilateral ureteral stents and a cystostomy tube. The dog was monitored in the intensive care unit for 7 d after surgery and was discharged 9 d after surgery and after the stent and cystostomy tube were removed. The dog remained clinically normal and was reported to have been euthanized at 11 y of age (2021) due to unspecified causes. Key clinical message: There are several potential causes of severe bilateral hydroureteronephrosis in animals. Based on this case report, dogs with severe bilateral hydroureteronephrosis that are clinically asymptomatic may have favorable outcomes following bilateral ureteral reconstruction and neoureterocystostomy, even if a definitive cause is not identified.

Néourétérocystostomie bilatérale avec effilement urétéral chez un chien avec hydrourétéronéphrose bilatérale sévère. Un labrador mâle non-castré âgé de 3,5 ans a été vu pour hématurie. Les résultats des tests de pathologie clinique ne présentaient pas d'anomalie. Toutefois, l'analyse d'urine a mis en évidence une urine foncée, trouble, alcaline et isosthénurique, contenant des globules rouges et blancs, des cellules épithéliales et des cristaux de struvite. Une augmentation bilatérale sévère de la taille des urètres ainsi qu'une augmentation de la taille des reins ont été notées lors des radiographies abdominales. Un examen par tomodensitométrie a révélé une hydrourétéronéphrose bilatérale marquée sans cause identifiable d'obstruction. On procéda à un effilement urétéral bilatéral avec néourétérocystostomie bilatérale et mise en place de stents urétéraux bilatéraux temporaires et un tube à cystotomie. Le chien a été sous surveillance à l'unité des soins intensifs pendant 7 j après la chirurgie et a obtenu son congé 9 j après la chirurgie, après que les stents et le tube à cystotomie aient été retirés. Le chien est demeuré cliniquement normal jusqu'à son euthanasie à l'âge de 11 ans (2021) pour des raisons non-spécifiées.Message clinique clé :Il y a plusieurs causes potentielles d'hydrourétéronéphrose bilatérale chez les animaux. Sur la base de ce rapport de cas, les chiens avec hydrourétéronéphrose bilatérale sévère qui sont cliniquement asymptomatique un résultat favorable peut être obtenu à la suite d'une reconstruction urétérale bilatérale et une néourétérocystostomie même si une cause définitive n'est pas identifiée.(Traduit par Dr Serge Messier).

Clinical use of uncovered balloon-expandable metallic biliary stents for treatment of extrahepatic biliary tract obstructions in cats and dogs: 11 cases (2012-2022).

OBJECTIVE: To describe the application of uncovered balloon-expandable metallic biliary stents for treatment of extrahepatic biliary obstructions (EHBOs) and the outcomes for dogs and cats treated for EHBO with this technique. STUDY DESIGN: Retrospective single institutional study. ANIMALS: Eight dogs and three cats treated at the Veterinary Specialty Hospital of San Diego for EHBO between January 2012 and February 2022. METHODS: Data collected from the medical records included signalment, presenting complaint, laboratory and imaging findings, surgical findings, hospitalization time, complications, and follow-up information. RESULTS: Median duration of short-term follow up was 16 days (6-45 days). Improved biochemical abnormalities and resolution of clinical signs were recorded in 10/11 cases. Two dogs died within 2 weeks of surgery. One dog developed systemic inflammatory response syndrome 5 days postoperatively and was euthanized; the cause of death in the second case was unknown. Long-term follow up was available in seven cases, with a median duration of 307.5 days (62-2268 days). Bile-duct patency was maintained for at least 356-622 days (median: 446 days) in three cats and 62-2268 days (median: 650.5 days) in four dogs with long-term follow up available. One cat had recurrent obstruction with choledocholiths 446 days postoperatively. One stent was removed 614 days postoperatively due to recurrent cholangiohepatitis. CONCLUSION: Uncovered balloon-expandable metallic biliary stents were placed successfully and relieved EHBO in all cases that survived to discharge. CLINICAL SIGNIFICANCE: Use of uncovered balloon-expandable metallic biliary stents should be considered as an alternative to temporary choledochal luminal stenting or cholecystoenterostomy to manage EHBO.

Laryngeal silicone stent as a treatment option for laryngeal paralysis in dogs: a preliminary study of 6 cases.

BACKGROUND: Laryngeal paralysis is a common idiopathic degenerative neurological disease in older medium-to-large breed dogs, with surgical correction of the obstruction being the treatment of choice. OBJECTIVES: This study evaluated the use of laryngeal silicone stents to treat canine laryngeal paralysis in dogs where classic surgical treatment was not accepted by the owners. METHODS: Dogs diagnosed with laryngeal paralysis, for which the owners refused arytenoid lateralization surgery as a first-line treatment, were treated with laryngeal silicone stents. RESULTS: Six dogs with bilateral laryngeal paralysis were included in the study. All dogs showed improvement in clinical signs immediately after the procedure. No clinical signs or radiographic changes were noted in four out of six dogs in the follow-up visit performed 1 wk later. One dog was suspected of aspirating water while drinking, but the signs disappeared after repositioning the stent. Another dog had a relapse of stridor due to caudal migration of the stent. This dog underwent arytenoid lateralization surgery because larger stents are not commercially available. At the time of writing, between seven and 13 mon after stent placement, no significant incidents have occurred in four dogs, and all owners report a satisfactory quality of life. CONCLUSIONS: Laryngeal silicone stenting is an interesting alternative for treating dogs with acquired laryngeal paralysis when the owners refuse classic arytenoid lateralization surgery. Furthermore, stent placement can be a temporary solution to stabilize these dogs until a permanent surgical treatment can be performed.

Multicenter retrospective evaluation of transmural migration of subcutaneous ureteral bypass devices within the digestive tract in cats.

BACKGROUND: Placement of a subcutaneous ureteral bypass (SUB) device is an effective method to relieve all causes of ureteral obstruction in cats. Complications involving migration within the gastrointestinal tract have been seldomly described. OBJECTIVES: To characterize transmural migration of SUB devices within the digestive tract in cats. ANIMALS: Eleven migrated SUB catheters identified in 8 cats between 2017 and 2021. METHODS: Retrospective review of medical records of cats with a SUB device in which migration into the gastrointestinal tract was identified. RESULTS: The median time from SUB device placement to implant migration was 928 days (201-2298 days). Seven cats had obstruction of the SUB device and a positive urine culture at diagnosis. The migration was identified by ultrasound in 6/11, pre-operative contrast radiography in 2/2, and only at time of surgery in 3 SUB devices. All cats underwent surgical correction. Four nephrostomy and 7 cystotomy catheters migrated. Migration occurred into the duodenum (3/11), jejunum (7/11), and colon (1/11). SUB devices were removed in 7 cats and replaced in 2 cats, with 1 cat diagnosed with 2 migration events. Gastrointestinal resection and anastomosis were performed in 7/8 cats and an enterotomy in 2 cats. Six cats survived to discharge. The median follow-up time after migration diagnosis was 365 days (range, 0-1114 days) and 2 cats are still alive. CONCLUSIONS AND CLINICAL IMPORTANCE: Although a rare complication, migration of SUB device should be considered in cats with SUB device obstruction and a positive urine culture.

Transmural migration of a subcutaneous ureteral bypass into the intestine in three cats.

Subcutaneous ureteral bypass™ is a device placed in cats with ureteral obstruction. The most common complications include system occlusion, urinary tract infection and sterile cystitis. In this case series, we describe three cats with subcutaneous ureteral bypass devices placed where transmural migration of subcutaneous ureteral bypass catheters into the small intestine resulted in gastrointestinal signs, urinary infection and subcutaneous ureteral bypass occlusion. The system was changed in one case and removed in the other two. In all cases, an intestinal resection and anastomosis was performed. All cats had a good medium-term outcome, and urinary infection persisted in the case for which the subcutaneous ureteral bypass system was changed. Transmural migration of the device should be ​considered in cats with subcutaneous ureteral bypass presenting with persistent urinary tract infection, gastrointestinal signs or device obstruction, even if imaging studies such as ultrasound or contrast studies do not demonstrate any abnormalities.

Transmembrane stent placement for cor triatriatum dexter in six dogs.

OBJECTIVES: Report the long-term outcomes following transmembrane stent placement as a therapy for Cor Triatriatum Dexter (CTD). MATERIALS AND METHODS: Retrospective case series including six dogs with CTD treated with transmembrane stent placement. Follow-up information was obtained including the persistence of presenting clinical signs, additional therapies required, and survival. RESULTS: The median follow-up time was 24 months (range 15-76 months). Long-term outcome was deemed excellent in four dogs (67%), good/fair in one dog (17%), and poor in one dog (17%). Three dogs had persistence of clinical signs of variable severity. These three dogs were Labrador Retrievers or their crosses with varying degrees of tricuspid valve dysplasia (TVD), two of which also had a right to left shunting patent foramen ovale (PFO). One of these three dogs died 23 months post-stent placement during attempted open-heart repair of the TVD and PFO. Another is alive 15 months post-operatively stable on medical therapy for right-sided congestive heart failure secondary to TVD. The final dog demonstrated improved but persistent mild exercise intolerance up to 76 months post-operatively associated with mild TVD and a concurrent PFO. CONCLUSIONS: Transmembrane stent placement for CTD is a viable long-term treatment option with improvement or resolution of clinical signs. In the presence of concurrent congenital heart disease, specifically Labradors with TVD, additional therapies may be necessary with a corresponding impact on prognosis.

Stenting of the caudal aorta and aortic trifurcation for the treatment of thrombosis in 7 dogs.

BACKGROUND: Aortic and aortoiliac thrombosis in dogs causes disease and death. OBJECTIVE: To describe the procedure and outcomes for stenting the caudal aorta and aortoiliac trifurcation. ANIMALS: Seven client-owned dogs that underwent aortic/aortoiliac stenting for treatment of thrombosis. METHODS: Retrospective multi-center investigation. Medical records were reviewed for dogs that underwent stenting of the aorta or aortoiliac trifurcation between 2008 and 2020. Information collected included history, signalment, clinicopathologic data, diagnostic imaging, procedure reports, and outcomes. RESULTS: Seven dogs with an occlusive thrombus located at or near the aortic trifurcation were included. Four of 7 dogs were non-ambulatory. Hind limbs were paretic in 5 dogs, paralyzed in 1 dog, and claudication alone was noted in 1 dog. Five of the 7 dogs had protein-losing nephropathy (PLN). Of 5 dogs with PLN, 1 had protein-losing enteropathy (PLE) and controlled hypothyroidism and 1 had caudal aortic chondrosarcoma. Two dogs had no identified underlying disease. Angiography was performed before catheter directed thrombolysis and stent placement. No deaths occurred during the procedure. Postoperative complications included pain (4/7), bruising and edema (3/7), bruising only (1/7), and edema only (1/7). Median survival time (MST) of the 7 dogs was 264 days (range, 1-1053 days). Five of 7 dogs were ambulatory within 2 days of stenting and survived to discharge with a MST of 425 days (range, 208-1053 days). CONCLUSIONS AND CLINICAL IMPORTANCE: Stenting of the aorta and aortoiliac trifurcation can provide an apparently safe and effective treatment with rapid return to ambulation for some dogs with aortic thrombosis.

Bronchial Stent Placement for Palliative Treatment of Pulmonary Carcinoma with Bronchial Obstruction in a Cat.

A feral, domestic shorthair was evaluated for palliative treatment of a pulmonary mass with secondary pneumonia. Because of the patient's temperament and extent of the mass, tracheobronchoscopy, bronchial stenting, and biopsy were elected, followed by adjuvant radiation therapy. Stent placement across the malignantly obstructed bronchus permitted drainage and recruitment of the infected lung lobe. Uncomplicated radiation therapy, stent extension, and debulking due to tissue ingrowth were subsequently performed. Successful palliation was achieved for 323 days with subsequent progressive pulmonary and liver metastases.

Direct renal pelvicocystostomy using tube cystoplasty in a cat with ureteral obstruction.

We describe a surgical technique to re-establish urine flow in a 3-year-old Scottish Fold cat. A ureteral stent and subcutaneous urinary bypass failed after their placement due to rapid mineralisation of the lumen. Direct pelvicocystostomy anastomosis using a modified tube cystoplasty technique was performed. A wide rectangular apex-based full-thickness flap was created from the ventral aspect of the urinary bladder, which was sutured longitudinally to form a large-diameter tube. The resulting tube-shaped portion of the bladder was then directly anastomosed to the renal pelvis. No major postoperative complications were observed and no further recurrence of obstruction of the upper urinary tract was noted during follow-up. The cat died at home 481 days postoperatively from an undetermined cause. A pelvicocystostomy technique can be considered as an alternative salvage surgical technique for obstructive ureteral disease in cats.

Current Concepts in Urinary Surgery.

Management of canine and feline ureteral obstructions and urinary incontinence can be both controversial and frustrating. There has been a movement toward minimally invasive procedures, which in certain cases, can be used to both confirm the diagnosis as well as treat the condition. This chapter focuses on the advancements in urologic surgery associated with ureteral obstruction and urinary incontinence with primary focus on ureteral stenting, subcutaneous ureteral bypass systems, transurethral bulking agents, and hydraulic occluders.

Evaluation of preoperative ultrasonographic parameters to predict renal recovery in long-term survivors after treatment of feline ureteral obstructions: 2012-2019.

OBJECTIVES: The aim of this study was to determine whether preoperative ultrasound imaging characteristic(s) in cats suffering from unilateral benign ureteral obstructions are predictive of outcome after successful renal decompression with a subcutaneous ureteral bypass (SUB) device. METHODS: This was a retrospective study of 37 cats with unilateral, benign ureteral obstruction. Preoperative imaging characteristics (including renal pelvis diameter, parenchymal thickness [transverse plane], renal length and pelvic size:overall renal size) and biochemical data were evaluated for all cats diagnosed with a unilateral ureteral obstruction treated with a SUB device. Any patient with bilateral obstructions or documented bacteriuria/infection in the data collection period was excluded. All patients were followed between 3 and 6 months postoperatively to obtain postoperative biochemical data. Long-term outcome was defined as serum creatinine concentration at 3-6 months postoperatively. RESULTS: No preoperative imaging characteristics or biochemical findings were found to be significantly associated with long-term serum creatinine concentrations. The length of the kidney was found to be associated with change in blood urea nitrogen and creatinine with decompression but not with long-term renal values. CONCLUSIONS AND RELEVANCE: In this study, long-term renal function based on preoperative ultrasound imaging findings could not be predicted in cats with unilateral ureteral obstruction, regardless of the severity of the biochemical parameters, renal pelvic dilation (large or small pelvis), kidney size or thickness of renal parenchyma assessed.

Subcutaneous ureteral bypass device placement in 81 cats with benign ureteral obstruction (2013-2018).

BACKGROUND: Benign ureteral obstructions (BUOs) present a therapeutic challenge in cats. HYPOTHESIS/OBJECTIVES: The purpose of this study was to determine the outcome and complications associated with placement of subcutaneous ureteral bypass (SUB) device in cats. ANIMALS: Eighty-one client-owned cats (117 kidneys) with BUO treated by placement of a SUB. METHODS: Retrospective study. Medical records of cats with BUO and treated by SUB device placement between 2013 and 2018 were reviewed. Outcome and complications were documented. RESULTS: Hospital discharge rate was 94% (76/81). Serum creatinine on admission and at the time of discharge was 5.3 mg/dL (range, 1.2 to >15 mg/dL) and 2.1 mg/dL (range, 1.1-12.5 mg/dL), respectively. Luminal obstructions were documented in 17% (18/109) of the SUB devices of 16 cats discharged from the hospital. Infection was documented in 26% (20/76) of discharged cats. Kink of the device was documented in 10% (12/117) of devices. Time to luminal obstruction and kink were 204 days (range, 21-1678 days) and 58 days (range, 2-601 days), respectively. Fourteen of 81 (17%) cats required a revision surgery in order to restore patency of the device. At the time of writing, 53% (43/81) of cats were alive, with a mean survival time of 821 days (range, 1-2170 days) after surgery. Of those that died, 52% (20/38) died of urinary related causes. CONCLUSION AND CLINICAL IMPORTANCE: This study suggests that SUB device placement is associated with good outcomes and could be considered for the treatment of BUO in cats.

NEOURETEROCYSTOSTOMY AND URETHRAL STENT PLACEMENT IN A BLACK-HANDED SPIDER MONKEY (ATELES GEOFFROYI).

A 27-y-old female black-handed spider monkey (Ateles geoffroyi) was evaluated 13 d after an ovariohysterectomy because of abdominal distension, anorexia, and absent urination. The animal was diagnosed with a uroabdomen and urethral obstruction from computed tomographic findings and fluid creatinine levels. During exploratory laparotomy, a defect in the right ureter was confirmed as the source of the uroabdomen. Utilizing intraoperative fluoroscopy, a urethral obstruction with an irregular luminal filling defect was evident. A self-expanding nitinol urethral stent was placed, and a ureteral transposition was performed. Two months after the procedure, the animal developed dysuria, a urinary tract infection, recurrent bladder distension and a partial urethral obstruction. Treatment with prazosin 1 mg/kg PO q12h improved urination. Reobstruction of the urethra occurred 17 mo postsurgery, and the animal was euthanatized. On postmortem examination, the animal had ingrowth into the stent with proliferative granulation tissue, detrusor muscle degeneration, pelvic adhesions, cystitis, pyelonephritis, and hydronephrosis.

Surgical Management of Feline Extrahepatic Biliary Tract Diseases.

Extrahepatic biliary obstruction occurs infrequently in cats. Pathophysiology of biliary obstruction is characterized by cholestasis, obstruction, inflammation, and exudation. Clinical signs and laboratory examination findings are nonspecific. Ultrasonographic examination of the biliary tract aids significantly in diagnosis. The aims of feline biliary surgery are to determine the underlying cause and extent of the obstruction, restore bile flow to the gastrointestinal tract, and prevent bile leakage and subsequent peritonitis. Surgical techniques to restore bile flow and decompress the biliary distension include cholecystostomy tube placement and choledochal stenting, cholecystectomy, choledochotomy, and biliary diversion procedures. Surgical management of extrahepatic biliary obstruction carries a fair to guarded prognosis. Cats undergoing biliary diversion procedures have poorer outcomes than those undergoing nondiversion procedures. Cats with neoplastic involvement have significantly shorter lives than those with inflammatory involvement.

Removal and repositioning of urinary tract implants by use of an endovascular snare system in dogs and cats (2013-2019).

OBJECTIVE: To report the fluoroscopic removal or repositioning of urinary tract implants in dogs and cats by use of an endovascular snare system (ESS) and to report procedural usefulness and complications in dogs and cats. ANIMALS: 3 cats and 14 dogs. PROCEDURES: A medical records review was performed to identify dogs and cats that underwent removal or repositioning of urinary tract foreign bodies or implants by use of an ESS with fluoroscopic guidance at a veterinary teaching hospital from 2013 to 2019. RESULTS: Dogs had a median weight of 25 kg (55 lb) with a range of 3.5 to 60.6 kg (7.7 to 133.3 lb), and cats had a median weight of 5 kg (11 lb) with a range of 4.2 to 5.4 kg (9.2 to 11.9 lb). By use of an ESS, 12 patients (2 cats and 10 dogs) underwent transurethral retrieval of retained vesicourethral implants or ureteral stents, 2 dogs underwent transurethral ureteral stent repositioning, 1 cat and 2 dogs underwent transnephric retrieval of ureteral stents, and 1 dog underwent cystoscopic-assisted transureteral ureteral stent retrieval. All procedures were successfully performed, and there were no associated procedural complications. CONCLUSIONS AND CLINICAL RELEVANCE: Retained vesicourethral implants or ureteral stents were successfully retrieved by use of an ESS in dogs and cats transurethrally or with an open or percutaneous transnephric approach and fluoroscopic guidance. These techniques should be considered as an alternative or adjunct to more invasive methods for implant retrieval or manipulation.

Treatment of a heart base tumor and chylothorax with endovascular stent, stereotactic body radiation therapy, and a tyrosine kinase inhibitor in a dog.

An 8-year-old 28-kg male castrated rough collie was evaluated for persistent chylothorax secondary to right atrial mass. Cardiac ultrasound and computed tomography revealed a right atrial intra- and extraluminal mass with partial obstruction of the cranial vena cava and secondary chylothorax. Vascular stent placement was elected to alleviate cranial vena cava obstruction and secondary chylothorax. An 18 mm × 180 mm self-expanding stent was deployed in the region of the stricture, spanning the cranial vena cava and right atrium. An intrathoracic drainage catheter and subcutaneous port were placed within the right hemithorax, and antiplatelet therapy was initiated. Four weeks later, the dog underwent stereotactic body radiation therapy. Three months following treatment, the dog was diagnosed with supraventricular tachycardia and received antiarrhythmic therapy and antiangiogenic/antiproliferative medication (Palladia™). Subsequent evaluations confirmed the resolution of arrhythmia and pleural effusion. Combined vascular stent placement and stereotactic body radiation therapy for the treatment of a right atrial intraluminal and extraluminal mass leading to cranial vena cava compression and subsequent chylothorax may lead to long-term survival. A good outcome was achieved in this patient due to resolution of pleural effusion, as well as cytoreduction and presumably delayed progression of tumor growth.