Survival and complications in cats treated with subcutaneous ureteral bypass.

OBJECTIVES: To report the complications and factors affecting outcome for cats following placement of a subcutaneous ureteral bypass (SUB™). MATERIALS AND METHODS: In this retrospective study, complications, the presence of a urinary tract infection and survival time were recorded following subctutaneous ureteral bypass placement. Factors affecting survival time were assessed using a Kaplan Meier curve and log rank test. RESULTS: Ninety-five cats had 130 subcutaneous ureteral bypasses placed. Ten cats did not survive to discharge. Forty cats died or were euthanised after discharge (42%); the median survival time of these cats was 530 days (range 7 to 1915). Minor complications occurred in 18 cats (19%) and major complications occurred in 46 cats (48%), the majority of which were after hospital discharge. Twenty-seven cats were diagnosed with a urinary tract infection (UTI) post-operatively. A significant association between long-term survival and creatinine at presentation was identified. The median survival time for cats presenting with creatinine concentration ≥440 µmol/L (International Renal Interest Society stage acute kidney injury (AKI) 4 and 5) was 530 days (95% CI 273-787 days), compared to a median survival time of 949 days (95% CI 655-1243 days; Log Rank P=0.024) for those cats presenting with creatinine <440 µmol/L (International Renal Interest Society stage AKI 1-3). CLINICAL SIGNIFICANCE: In this population of cats, subcutaneous ureteral bypass placement was associated with an approximately 10% in-hospital mortality and a high complication rate. Most complications were manageable, resulting in an overall median survival time of over 2 years.

Diagnostic imaging observations in cats treated with the subcutaneous ureteral bypass system.

OBJECTIVES: To describe pre- and post-operative ultrasonographic and fluoroscopic findings, including any abnormalities, in cats treated for ureteral obstruction with a subcutaneous ureteral bypass system. METHODS: Retrospective review of imaging findings in cats with ureteral obstruction that had surgery to place the first version of the bypass system and at least one follow-up ultrasound or fluoroscopic study. Pre- and post-operative renal pelvic diameter on ultrasound, fluoroscopic appearance of the bypass system and any related abnormality were recorded. RESULTS: Eighty-one cats were included (47 unilateral, 34 bilateral bypass systems). Median preoperative renal pelvic diameter was 9 mm (range 3 to 28 mm) and median renal pelvic diameter at the first postoperative ultrasound was 3 mm (range 2 to 23 mm). The median number of postoperative imaging studies was two (range 1 to 8) and the median follow-up period after surgery was 205 days (range 1 to 1378 days). Bypass system abnormalities were identified postoperatively in 43 (53%) cats, including nephrostomy or cystostomy catheter blockage due to an undetermined cause or kinking of the catheter, nephrostomy or cystostomy catheter leakage, non-obstructive kinking of the catheter and loose nephrostomy pig-tail loop. Many abnormalities required repeat surgery, but others were managed conservatively. Fifty-four percent of obstructed ureters became patent after bypass placement, although the majority remained slightly dilated or had irregular margins compatible with chronic inflammation. CLINICAL SIGNIFICANCE: Bypass abnormalities, mainly tube blockage, occurred frequently in cats treated for ureteral obstruction. Ultrasonography and fluoroscopy were useful for postoperative examination, including documenting renewed ureteral patency and investigation of suspected abnormalities.

Surgical management of impalement injuries to the trunk of dogs: a multicentre retrospective study.

OBJECTIVES: To review a large series of dogs referred for treatment of traumatic impalement injuries to the thorax and/or abdomen and to report aetiologies, injury characteristics, management and long-term outcomes. MATERIALS AND METHODS: Previously collected data on dogs that were surgically treated for impalement injuries to the trunk at six veterinary specialist referral institutions in the UK over an 11-year period were reviewed. Data included patient signalment, physiological variables, injury-specific variables, diagnostic imaging reports, surgical procedures undertaken, duration of hospitalisation, antibiotic use, complications and outcomes. Data were reported with summary statistics. RESULTS: Fifty-four dogs were included. Impalement occurred most frequently on wooden objects (n=34), and the thoracic cavity was most commonly penetrated (n=37). Computed tomography was sensitive and specific to identifying wooden material in 64% and 88% of cases (n=11), respectively. Thoracotomy was performed in 56%, coeliotomy in 20% and a foreign body or its fragments were retrieved during surgery in 37% of the cases. Complications occurred in 19 dogs (35%), and of these, 68% were minor and 32% major. The survival rate for thoracotomy cases was 93% (n=30). Overall long-term survival was 90%. CLINICAL SIGNIFICANCE: Despite the often dramatic presentation of impalement injuries, the majority of patients treated in the specialist referral setting can achieve excellent outcomes. These injuries require thorough diagnostic imaging and interpretation before adequate surgical exploration and management, augmented by anaesthesia and critical care during the peri- and postoperative periods; therefore stable patients should be referred to centres able to provide this type of care.

A retrospective study of the use of active suction wound drains in dogs and cats.

OBJECTIVES: To report indications for use and complications associated with commonly used closed active suction wound drains in a large number of clinical cases. METHODS: Retrospective review of medical case records (from 2004 to 2010) for dogs and cats that had a closed active suction drain placed into a wound. Only the four most common drain types were included: Mini Redovac®, Redovac®, Jackson Pratt® and Wound Evac®. RESULTS: Two hundred and fifty-three drains were placed in 33 cats and 195 dogs. Mini Redovac drains were used most frequently in cats (76 · 5%) and Redovac drains in dogs (54 · 3%). The infection rate for clean surgeries in dogs was 15 · 6% (unattainable in cats). Major complications occurred in four dogs; minor complications occurred in 12 drains in cats (35 · 3%), and in 74 drains in dogs (33 · 8%). There was no statistically significant association between the type of drain and complication rate for either species. CLINICAL SIGNIFICANCE: Although closed active suction drains can be used with low risk of major complications, they lead to a high rate of infection in clean surgeries in dogs. It is recommended that such drains are kept in place for the shortest time possible and that strict asepsis is adhered to both during placement and management.

Pulmonary lipoma in a dog.

An eight-year-old, neutered, male German short-haired pointer was presented for a chronic cough and an intrathoracic mass. Computed tomography revealed a mass with low attenuation in the right caudal lung lobe that invaded the principal bronchi. The mass was removed by right caudal and accessory lung lobectomy. The histopathological diagnosis was pulmonary lipoma. The clinical signs resolved following surgery. There was no evidence of recurrence or de novo lesions on computed tomography performed 12 months post-surgery. To the authors' knowledge, this is the first report of a pulmonary lipoma in a dog.

Prevalence, outcome and risk factors for postoperative pyothorax in 232 dogs undergoing thoracic surgery.

OBJECTIVE: To determine the prevalence, outcome and risk factors for postoperative pyothorax in dogs undergoing thoracic surgery. METHODS: Case records were reviewed retrospectively to identify dogs with post thoracic surgery pyothorax, defined as septic neutrophilic inflammation within the pleural space based on cytology and/or a positive bacterial culture of pleural fluid. Those identified were reviewed for potential risk factors for postoperative pyothorax based on biological plausibility and previously published data. These potential risk factors were explored by multivariable logistic regression. RESULTS: Of 232 dogs undergoing thoracic surgery, 15 (6.5%) dogs developed pyothorax. Bacteria cultured included methicillin-resistant Staphylococcus aureus and multi-resistant Escherichia coli. Of these dogs, six died, four were euthanased and five were treated successfully. A diagnosis of idiopathic chylothorax [Odds Ratio (OR)=12.5, 95% Confidence Interval (CI)=2.7-58.5, P=0.001], preoperative intrathoracic biopsy (OR=14.3, 95% CI=1.7-118.7, P=0.014) and preoperative thoracocentesis (OR=11.2, 95% CI=1.6-78.2, P=0.015) were identified as independent risk factors for development of postoperative pyothorax. CLINICAL SIGNIFICANCE: Idiopathic chylothorax, intrathoracic biopsy and prior thoracocentesis are independent risk factors for postoperative pyothorax, which was associated with a 67% mortality rate.

Airway injury associated with cervical bite wounds in dogs and cats: 56 cases.

OBJECTIVE: To investigate the frequency of airway injury and damage to other vital structures associated with cervical bite wounds in dogs and cats and the implications for management and outcome. METHODS: A retrospective search of electronic patient records was used to identify dogs and cats suffering cervical bite wounds that were presented to a large multidisciplinary veterinary hospital over a four year period. RESULTS: Complete records were available for 55 animals, with one animal suffering two separate injuries. Fourteen animals (25%) had injuries to vital structures, including airway injury in nine (17%) which was surgically confirmed and treated in six (11%). Airway injuries were associated with either subcutaneous or mediastinal emphysema in all affected animals. Other structures injured included the jugular vein, pharynx, oesophagus and spine. Airway injuries were treated with primary repair in five animals and a fasciomuscular patch in one. Temporary tracheostomy was performed in three animals. Median duration of hospitalisation was one day (0-19) with 53 animals (54 cases) (96%) surviving to discharge. Long-term follow-up (16-114 months) revealed that 43 of 49 animals were alive with six that died due to unrelated reasons. CLINICAL SIGNIFICANCE: Cervical bite wounds are associated with significant injury to vital structures. Up to 17% of animals may have injury to their airway. Identification and treatment of airway injury is vital and was associated with an excellent outcome in six animals.

Management of peristomal tissue necrosis following prepubic urethrostomy in a cat.

This report describes the successful management of peristomal tissue necrosis following prepubic urethrostomy in a cat. The novel technique of temporary urethral ligation was used in combination with temporary tube cystostomy and vacuum assisted closure to allow for wound management prior to performing wound closure by utilization of a flank fold skin flap then definitive prepubic urethrostomy. Eleven month follow-up indicated excellent outcome with the cat having returned to normal behaviour apart from having adapted its posture to urinate.

Computed tomographic findings in canine pyothorax and correlation with findings at exploratory thoracotomy.

OBJECTIVES: To describe computed tomographic (CT) findings in canine spontaneous pyothorax and compare them to surgical findings and to assess the utility of CT in guiding case management. METHODS: Records from 2003 to 2010 were reviewed to identify dogs, with spontaneous pyothorax, which had undergone CT. Cases were managed medically or surgically. CT images and surgery reports were reviewed and compared for surgical cases. RESULTS: Twelve dogs were included. Eight were managed surgically, three were managed medically and one died before management. Pleural fluid was present in all dogs on CT (n=12) and at surgery (n=8). Pleural gas was identified in five dogs on CT. Pleural thickening was detected in eight dogs on CT (seven visceral, one parietal and six mediastinal) and eight dogs at surgery (seven visceral, eight parietal and six mediastinal), six of which were identified by CT. Abnormal pulmonary parenchyma was detected in 10 dogs on CT and 5 dogs at surgery, all of which were identified by CT. Mediastinal involvement was detected in 10 dogs on CT and 6 dogs at surgery, 5 of which were identified by CT. CONCLUSIONS: CT and surgical findings are similar in most cases of canine spontaneous pyothorax. CT may be a useful diagnostic tool for guiding case management.

Postoperative haemorrhage associated with active suction drains in two dogs.

This article describes two dogs in which an active suction drain was placed to manage dead space at the surgical site and acute haemorrhage and hypovolaemia occurred postoperatively. In both instances, fluid resuscitation and temporary discontinuation of drainage resulted in resolution of clinical signs. Although the underlying cause of haemorrhage was not definitively identified, the use of low-pressure drainage systems and avoidance of interference with local blood vessels should be considered. This is a previously undocumented complication of active suction drain use in veterinary patients.

Cavitary pulmonary lesion associated with Aspergillus fumigatus infection in a German shepherd dog.

A two-year-old female German shepherd dog was presented with chronic cough and haemoptysis. Thoracic radiographs revealed a thin-walled cavitary lesion within a consolidated left cranial lung lobe. Bronchoalveolar lavage confirmed a concurrent bacterial infection; however, despite antibiotic and anthelmintic therapy the clinical signs failed to resolve. A left cranial lung lobectomy was performed. Histopathology and fungal culture confirmed the presence of Aspergillus fumigatus. The necrotic cavity had features compatible with a bronchial origin, possibly a form of cystic bronchiectasis, arising either as a congenital anomaly or acquired secondary to infection. Surgery provided resolution of clinical signs for just over a year before the dog deteriorated again and was subsequently euthanised. Necropsy was declined by the owners. This case report presents a unique presentation in which the predominant clinical sign was coughing due to pulmonary involvement. Aspergillus fumigatus was isolated from the left cranial lung lobe.

Computed tomography as an aid to management of chronic oropharyngeal stick injury in the dog.

OBJECTIVE: To describe the use of computed tomography scanning in the management of dogs with chronic signs after oropharyngeal stick injury. METHODS: Dogs with a final diagnosis of chronic oropharyngeal stick injury that underwent a computed tomography scan during their investigation were selected retrospectively from case files at the Royal Veterinary College, London. RESULTS: The six dogs were young (median age 3.1 years) and medium to large breed (19.0 to 42.0 kg). By the time of referral the most common clinical sign was cervical swelling (five dogs). Stick foreign bodies were apparent on the plain computed tomography images in all cases and appeared as well-demarcated, linear abnormalities. A ventral mid-line approach was used for foreign body retrieval, and the computed tomography findings corresponded well with the surgical findings, with stick foreign body length ranging from 1 to 7 cm. Closed suction drainage was used in five dogs, for two to four days. Clinical signs fully resolved postoperatively in all cases, although cervical swelling recurred three weeks after surgery in one case. This dog had the smallest foreign body, the greatest number of surgical interventions before referral (three) and the longest disease course before referral (eight months). CLINICAL SIGNIFICANCE: Computed tomography scanning is accurate in identifying the presence and location of chronic stick foreign bodies. Recurrence of disease is possible despite successful retrieval of the wood fragments found by computed tomography scan.

Indications, outcomes and complications following lateral thoracotomy in dogs and cats.

OBJECTIVES: Lateral thoracotomy is widely used for surgical management of thoracic diseases in small animals. The purpose of this paper is to describe the indications for lateral thoracotomy in dogs and cats and the associated outcomes and complications. METHODS: Medical records of animals undergoing lateral thoracotomy were reviewed and owners contacted regarding complications and survival. Relationships between signalment and treatment variables and outcome variables were investigated. RESULTS: Seventy dogs and 13 cats underwent lateral thoracotomy. Sixty-two per cent of cats and 91 per cent of dogs survived to discharge. Survival to discharge was significantly lower in cats than dogs, for neoplastic than non-neoplastic disease and in older animals. Survival to discharge was higher in animals undergoing patent ductus arteriosus ligation than in those undergoing lung lobectomy or oesophageal surgery. Survival to discharge was not related to surgeon experience. The incidence of complications was not related to species, age, disease, duration of surgery, surgeon experience or duration of thoracostomy tube placement. A low complication rate (5 per cent) was associated with thoracostomy tubes. CLINICAL SIGNIFICANCE: The approach of lateral thoracotomy has a minimal complication rate and animals with a disease requiring this approach have a high survival rate.

Torsion and volvulus of the transverse and descending colon in a German shepherd dog.

A German shepherd dog was presented two months after surgery for correction of acute gastric dilatation volvulus. The dog had been diagnosed with exocrine pancreatic insufficiency. Radiographs revealed marked gaseous distension of one loop of intestine with a generalised increase in intestinal gas content. A 360 degrees anticlockwise rotation of the descending and transverse colon, around the longitudinal axis of the mesocolon, was diagnosed at exploratory coeliotomy. The transverse and descending colon appeared uniformly necrotic and an end-to-end colo-colic resection and anastomosis was performed. The dog initially made satisfactory postoperative progress but was euthanased on the third postoperative day after it developed an intestinal intussusception.

Pancreatic exocrine responses to parasympathetic stimulation in anaesthetized pigs.

Pancreatic exocrine responses to stimulation of the peripheral ends of the vagus nerves intermittently have been investigated in anaesthetized pigs and compared with the effects of continuous stimulation at corresponding frequencies. At relatively low frequencies < or =20 Hz in bursts or 2 Hz continuously) both the flow of pancreatic juice and the output of protein therein were potentiated by stimulating in bursts. Thus stimulation at 20 Hz in bursts produced a significantly greater flow of pancreatic juice than stimulation at 2 Hz continuously (10.9+/-0.9 compared to 4.8+/-0.7 microl min(-1) (g gland)-1 , respectively; P<0.01). Likewise the output of protein during intermittent stimulation at 20 Hz (144+/-23 microg min(-1) (g gland)-1) far exceeded that produced during continuous stimulation at 2 Hz (49+/-9 microg min(-1) (g gland)-1; P<0.01). Both differences were abolished by atropine (0.5 mg kg(-1) i.v.), which augmented the flow during continuous stimulation (to 8.7 +/- 1.5 microl min(-1) (g gland)-1; P<0.05 at 2 Hz) and substantially reduced the output of protein during intermittent stimulation (to 27+/-7 ng min(-1) (g gland)-1; P<0.01 at 20 Hz in bursts). These results show that a variety of pancreatic exocrine responses can be enhanced by stimulating the parasympathetic innervation in bursts. They are also consistent with the contention that the secretion of protein from the gland, in response to parasympathetic stimulation, is dependent mainly on activation of muscarinic receptors. They confirm that the flow of pancreatic juice is due mainly to the release of VIP and show that, in the absence of atropine, this is restricted by muscarinic inhibition which may be presynaptic as elsewhere.