Preliminary evaluation of an indwelling epidural catheter for repeat methylprednisolone administration in canine lumbosacral stenosis.

Objective: To determine the complications, outcomes, and patency of a permanent epidural catheter and subcutaneous access port system (ECAPS) as part of conservative management of degenerative lumbosacral stenosis in dogs. Animals and procedure: Medical records of 11 client-owned dogs that underwent an ECAPS insertion were evaluated retrospectively. Clinical signs, complications related to the procedure, and system patency are reported. Results: All dogs had lumbosacral pain at their initial neurological assessment, with comfort levels adequately controlled following epidural infiltrations. None suffered from complications related to the ECAPS procedure. In 10 dogs, there were no malfunctions for the duration of the study. However, in 1 dog, there was a suspected leak at Day 814. The longest duration of patency reported in this study was 870 d (at the time of writing). Conclusion: Placement of an ECAPS is a feasible technique and a viable option to permit repeated epidural injections of steroids in dogs with degenerative lumbosacral stenosis that is managed conservatively. Further studies are required to evaluate complication rates.

Évaluation préliminaire d'un cathéter épidural permanent (à demeure) pour l'administration répétée de méthylprednisolone lors de sténose lombosacrée dégénérative chez le chien. Objectif: Décrire la technique, les complications, les résultats et la perméabilité d'un système composé d'un cathéter épidural et d'un port d'injection sous-cutanée (ECAPS) pour le traitement médical de la sténose lombosacrée dégénérative chez le chien. Animaux et protocole: Les dossiers médicaux de 11 chiens appartenant à des clients ayant subi l'implantation d'un ECAPS ont été évalués de façon rétrospective. Cette étude décrit les signes cliniques, les complications reliées à la procédure et la perméabilité du système. Résultats: Tous les patients inclus présentaient de la douleur lombosacrée à l'examen initial. Le niveau de confort de tous les patients suite aux injections épidurales fut maitrisé de façon adéquate. Aucun des patients n'a subi de complications reliées à l'implantation du système. Le système n'a pas démontré de dysfonctionnement dans le cas de dix patients. Chez un des patients, une fuite fut suspectée au jour 814. La durée maximale de perméabilité enregistrée dans cette étude est de 870 jours (au moment de la rédaction). Conclusion: L'implantation d'un système ECAPS représente une option faisable et viable pour l'administration additionnelle de stéroïdes pour une gestion conservatrice de sténose lombosacrée dégénérative chez les chiens atteints. Des recherches supplémentaires sont requises pour l'évaluation des taux de complications.(Traduit par les auteurs).

Retrospective evaluation of the use of small-bore wire-guided catheters for the management of peritoneal effusion in cats and dogs.

OBJECTIVE: To describe the use of small-bore wire-guided catheters in the management of peritoneal effusion in cats and dogs and to detail any associated adverse events. DESIGN: Retrospective study. SETTING: University teaching hospital ANIMALS: Forty-five client-owned animals that had peritoneal catheters placed for management of peritoneal effusion between July 2010 and June 2021. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Forty-five cases were included (25 dogs and 20 cats). Twenty-eight animals had the catheter placed to aid management of a uroabdomen, 8 of which recovered without surgical management, 11 had the catheter placed to allow autotransfusion of hemoabdomen, 3 had peritonitis, and 3 had ascites secondary to cardiac disease. Twenty-seven cases (15 dogs and 12 cats) received sedation (n = 24) or local anesthesia alone (n = 3) to facilitate catheter placement, and 6 cases had the catheter placed while under general anesthesia. Median length of catheter persistence was 24 hours (range: 2-144 h). The most common adverse events reported were impaired drainage (n = 7) and leakage at the insertion site (n = 4). CONCLUSIONS: Peritoneal catheters can be inserted percutaneously for management of peritoneal effusion. Indications include stabilization and conservative management of uroabdomen, and autotransfusion. They can often be placed with minimal or no sedation and adverse events appear infrequent in occurrence.

Subcutaneous vascular access port implantation in the axillary or femoral/external iliac vein at the time of full limb amputation in dogs.

OBJECTIVE: To report outcomes and complications after placement of a subcutaneous vascular access port (SVAP) in the jugular (jSVAP), axillary (aSVAP), and femoral or external iliac vein (fSVAP) in dogs. STUDY DESIGN: Retrospective. METHODS: Medical records from a single hospital, covering a period between September 2015 and October 2020, were reviewed to identify dogs that had an SVAP placed. Complications and outcomes for dogs who had an SVAP placed in the axillary vein, or femoral/external iliac vein during amputation for appendicular skeletal neoplasm, and in the external jugular vein were recorded and analyzed statistically. RESULTS: Subcutaneous vascular access ports were placed in the axillary vein in 13 dogs, femoral/external veins in 4 dogs, and in the jugular vein in 19 dogs. The SVAPs fulfilled their purpose throughout treatment in 12/13 aSVAP, 4/4 fSVAP, and 15/19 jSVAP. Dogs were followed for a median of 145.5 days (range 30-945 days). Minor and major complications were recorded in 1/13 and 2/13 aSVAPs, 0/4 and 0/4 fSVAPs, and 3/19 and 4/19 of jSVAPs. Two dogs with jSVAPs were euthanized due to SVAP-related complications. No difference in complication rate was detected between groups (P = .12). CONCLUSION: No difference in short-term outcome was detected between implantation sites for subcutaneous vascular access ports. CLINICAL SIGNIFICANCE: The axillary or femoral/external iliac veins offer alternative sites for placement of SVAP in dogs undergoing limb amputation.

[Venous catheters in horses - early ultrasonographic venous abnormalities and evidence of biofilms]. / Ultrasonografische Früherkennung von Venenveränderungen sowie der Nachweis von Biofilmen auf Venenverweilkathetern beim Pferd.

OBJECTIVE: Complications associated with indwelling intravenous catheters vary from minor to severe. Changes in tissue architecture and vein structure may be detectable prior to clinical alterations. The aim of the study was to characterize and compare changes in a catheterized vein and surrounding tissue by clinical and ultrasonographic examination. Microbiological infestation of catheter specimens was assessed. MATERIAL AND METHODS: In this prospective, observational, clinical study 55 horses with an indwelling intravenous catheter have been included. Subsequent to catheter placement, vein and surrounding tissue were daily examined clinically and by ultrasonographic examination at predetermined localizations. After sterile removal of the catheters, specimens underwent microbiological testing and scanning electron microscopy. Obtained data were analyzed via descriptive statistics. Thickness of the venous wall was compared at predetermined localizations and time points for several parameters with the help of non-parametric tests (level of significance at p < 0.05, post-hoc Bonferroni correction). RESULTS: Overall, in 41.8 % of the horses transient alterations (swelling) of the surrounding tissue occurred during catheterization. Median catheterization was 69.5 hours (19 hour-10 days). With ultrasonography, venous valves and collateral vessels could be detected reliably. Significant alterations in wall thickness during catheterization were associated with various factors (location site [p ≤ 0.001], season [p = 0.006], anesthesia [p ≤ 0.001]).Microbiological analysis revealed a positive result in 23.5 %, 12 of the 51 samples; raster electron microscopy showed presence of bacteria in 25.0 %, 4 of the 16 investigated catheter samples. CONCLUSION AND CLINICAL RELEVANCE: Local tissue changes at the insertion site of the catheter are commonly associated with catheterization, and are easily detectable with ultrasonography. Despite the easy performance in a clinical setting, the benefit of routine ultrasonographic monitoring of catheterized veins might be questionable with regard to early identification and prediction of catheter-associated venous disease. Bacteria might be detectable morphologically on the catheter but frequently lack a positive result from standard bacterial cultivation.

Clinical use and complications of percutaneous cystostomy pigtail catheters in 25 cats.

OBJECTIVES: The aims of this study were to describe the indications for percutaneous pigtail catheter placement in cats requiring urine diversion, and to report the associated intra- and postoperative complications. METHODS: The medical records of cats that underwent percutaneous pigtail catheter placement for urine diversion between January 2011 and May 2021 were retrospectively reviewed. RESULTS: Twenty-five cats were included. Indications for pigtail catheter placement were medical management of obstructive urinary tract disease (n = 12), urinary tract damage after traumatic injury (n = 8) and neurological bladder dysfunction (n = 5). Catheters were in place for a median time of 8.28 days (range 3-27), and the duration of the catheter placement was not different between the medical, traumatic and neurological groups. Ten cats (40%) developed pigtail catheter complications including dislodgement, urine leakage, urinary tract infection and bladder rupture. The majority of complications were easily resolved and did not require surgical intervention. CONCLUSIONS AND RELEVANCE: The results suggest that percutaneous pigtail catheter placement can facilitate urine diversion in both the emergency setting and in the long-term management of urine retention without many complications.

Occurrence and clinical management of urethral obstruction in male cats under primary veterinary care in the United Kingdom in 2016.

BACKGROUND: Urethral obstruction (UO) has a negative effect on welfare of cats. OBJECTIVES: This study aimed to determine incidence, case management, and outcomes of UO in cats in primary-care practice in the United Kingdom. ANIMALS: All male cats under veterinary care within the VetCompass database in 2016. METHODS: A retrospective cohort study was performed. The electronic records of all male cats with a clinical note during the study period were searched for UO cases and were manually reviewed for inclusion. Additional demographic and clinical information were extracted on cases. RESULTS: From the study cohort of 237 825 male cats, there were 1293 incident cases. The estimated UO incidence risk during 2016 was 0.54 (95% CI: 0.51-0.57). Demographic and clinical data were available for 1108 cases. Antibiotics were administered to 641/1108 (57.9%) cases. Overall repeat catheterization rate was 253/854 (29.6%). Repeat catheterization at 48 hours was less frequent in patients with indwelling catheters (10.1%) vs those that had a catheter placed and then immediately removed (14.8%; P = .04). Death during a UO episode was 329/1108 (29.6%), and 285/329 (88.0%) deaths involved euthanasia. CONCLUSIONS AND CLINICAL IMPORTANCE: Antibiotics were commonly prescribed in cats for treatment of UO despite minimal evidence in the clinical records of bacterial cystitis. Repeat catheterization was common and case fatality rate during a UO episode was high. Repeat catheterization within 48 hours of elective removal of a urethral catheter was less common in cats that had previously had indwelling catheters. The majority of cats requiring repeat catheterization survived until the end of the study.

A novel device for serial venous blood sampling in a canine model.

Diagnostic serial venous blood sampling has the potential to introduce stress-related artifactual elements into the analytical results. We have evaluated the use of a wearable automated serial blood sampling device in a canine model that obviates a need for multiple manual venipuncture. Efficacy in measuring cortisol levels during prolonged serial blood sampling is described. Automated serial blood sampling from the jugular vein was performed in two Beagle dogs. Over two separate 22-h periods, serial blood samples were withdrawn for routine cell counting and blood chemistries from each animal, whilst animal behavior along with durability of catheter placement and tolerability by the vascular system were assessed. During the study, no behavioral changes attributed to the serial blood sampling device were seen and no stress-related deviations from normal blood cell counts and cortisol levels were detected. Minor erythema was eident at the sites of catheter placement, which was consistent with the presence of an indwelling catheter. The wearable, serial blood sampling device performed well and was tolerated by the animals without stress-related changes in blood analysis or behavioral observation. This study has demonstrated the potential significant benefit of the Fluispotter® device for serial blood sampling in veterinary and clinical settings. The samples collected are free from stress-related signatures in blood chemistry otherwise common to serial blood sampling protocols requiring repeated venipuncture. This device has valuable implications for use in routine preclinical pharmacology and toxicology studies.

Evaluation of totally implantable catheters in healthy horses.

BACKGROUND: For horses requiring prolonged daily cephalic intravenous regional limb perfusion (IVRLP), the use of a totally implantable catheter (TIC) could be indicated to reduce complications associated with frequent venipuncture or external catheterization. This study aims to evaluate the implantation technique of the TIC in the cephalic vein of horses for IVRLP, describe the complications associated with the device's placement and use, and assess its viability up to 60 days after implantation. Totally implantable catheters, cut to 15 cm (n = 5) and 46 cm (n = 5) in length, were implanted into one cephalic vein in ten adult horses (n = 10). Twenty-four hours following placement, IVRLP with contrast was performed via the TIC and evaluated with radiography. Physical examinations, lameness evaluation, hematologic assessment, and the catheter patency tests were performed at scheduled intervals for the duration of catheterization (7-60 days). RESULTS: Catheters were implanted without difficulty and allowed for IVRLP 24 h post implantation. Complications resulted in removal of the catheters, with four maintained for 7 days, three in place for 15 days, and three catheters maintained for 60 days. Complications included lameness, limb swelling, catheter kinking, and venous thrombosis. CONCLUSIONS: The implantation technique of the TIC in the cephalic vein of horses is feasible and requires minimal technical effort. Although TIC allows venous access without the need for repeated venipuncture, its long-term use presents complications. For horses requiring prolonged daily cephalic IVRLP, the use of a TIC could be indicated. However, the high incidence of venous thrombosis may limit clinical application.

Influence of long-stay jugular catheters on hemostatic variables in healthy dogs.

OBJECTIVE: To compare hemostatic variables performed on blood samples obtained from indwelling jugular catheters or direct venipuncture over a 72-hour period. DESIGN: Prospective experimental study. SETTING: University research laboratory. ANIMALS: Five healthy neutered male purpose-bred Beagle dogs. INTERVENTIONS: Each dog was sedated to facilitate placement of a long-stay 20-Ga polyurethane IV catheter into the jugular vein. Blood samples were obtained from the preplaced catheters at 4 time points corresponding to 0, 24, 48, and 72 hours relative to placement. Blood samples were also obtained by direct venipuncture of a peripheral vein using a 21-Ga butterfly catheter and evacuated blood tubes at the same time points. Platelet count, platelet closure time, prothrombin time, activated partial thromboplastin time, fibrinogen, and kaolin-activated thromboelastography were performed on these paired samples at each time point. The patency of the indwelling catheters was maintained by flushing every 6 hours with heparinized saline. MEASUREMENTS AND MAIN RESULTS: No significant differences were identified in any of the hemostatic variables obtained by either blood collection technique at any time point during the study (P > 0.05). There was also no significant day-to-day variation in any catheter-derived hemostatic variable obtained from individual dogs identified over the course of the study. CONCLUSIONS: These data suggest that accurate hemostatic variables may be obtained using blood collected from indwelling jugular catheters, maintained with heparinized saline for at least 72 hours, in healthy dogs.

Characteristics of arterial catheter use and related complications in dogs and cats in an intensive care unit.

OBJECTIVE: To identify characteristics of arterial catheter use, including indwelling times and reasons for removal, and analyze potential risk factors for complications based on patient- and catheter-related variables. DESIGN: Prospective clinical study from July 2012 to September 2016. SETTING: University teaching hospital. ANIMALS: One hundred ninety-eight dogs and 29 cats with an arterial catheter monitored in the ICU. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A questionnaire was used to obtain patient and catheter information for arterial catheters monitored in the ICU during the study period. Two hundred twenty-seven catheters met the inclusion criteria. Most catheters were placed in the dorsal metatarsal artery in dogs (90.4%) and either the dorsal metatarsal artery (51.7%) or coccygeal artery (48.3%) in cats. Weights ranged from 1.5 to 64 kg in dogs and 0.77 to 8.7 kg in cats. The median indwelling time was 24 hours for dogs and 12 hours for cats. Minor complications occurred in 19.2% of catheters in dogs and 17.2% of those in cats with removal of catheter due to complications in 13 of 198 (6.6%) for dogs and 2 of 29 (6.9%) for cats. There was no association between the incidence of complications and patient weight, catheter indwelling time, species, insertion site, catheter size, or level of consciousness during placement. There was also no association between the method of catheter maintenance (intermittent flushing or continuous pressure transducer) and the failure of a catheter to aspirate or flush. CONCLUSIONS: Arterial catheter-related complications were relatively frequent, but most complications were minor and did not justify removal of the catheter. This suggests that the use of arterial catheters in both species is relatively safe. However, further research is needed to assess complications related to longer catheter indwelling times, particularly in cats.

A novel insertion technique for urinary catheters in female dogs with the use of a guidewire.

BACKGROUND: Complicated transurethral urinary bladder catheterization in female dogs is a commonly encountered urologic problem, often causing inadvertent trauma to the lower urinary tract and breach in aseptic technique. KEY CONCEPTS: A novel method for transurethral insertion of urinary catheters in female dogs is described. The main variation from current procedures involves the application of the Seldinger technique with the use of an introduction catheter that is specifically designed to feed into the urethra, and the use of a guidewire to replace the introducer with an indwelling balloon catheter. SIGNIFICANCE: The technique presented offers a step-by-step approach that could improve success in urinary catheter placement. This modification may facilitate catheter insertion, be less traumatic, and offer better control of asepsis, especially with challenging urethral catheterization. The technique also offers an easy method to replace the catheter. Application of the technique may reduce catheter-associated urinary tract infections as it addresses certain infection-related risk factors. Prospective validation studies are needed to support its advantages over current urinary catheter placement techniques.

Retrospective evaluation of urinary indwelling catheter type in cats with urethral obstruction (January 2014 to December 2014): 91 cases.

OBJECTIVE: To investigate the influence of urinary catheter type on recurrence rate (rUO) in cats with urethral obstruction. DESIGN: Retrospective study. SETTING: Two private referral hospitals. ANIMALS: Ninety-one cats diagnosed with urethral obstruction treated with a 3.5-Fr Argyle (AR) or 3.5-Fr red rubber (RR) indwelling catheter presenting in 2014. MEASUREMENTS AND MAIN RESULTS: One hundred sixty-six cats were identified using diagnostic code search with 91 cats meeting inclusion criteria. All were treated with IV fluids, buprenorphine, prazosin, and an indwelling urethral catheter with a closed collection system. Catheter groups did not differ statistically in baseline characteristics, medication treatment, or catheterization time. Follow-up was available for 91 cats at 24 hours, 86 cats at 7 days, and 84 cats at 30 days. There was no statistical difference in rUO between cats with different catheter types at any time in this retrospective study. CONCLUSIONS: No difference in rUO was found in cats treated for urethral obstruction with a 3.5-Fr AR or RR catheter, however, due to the retrospective nature of this study the inability to detect a difference may be due to the small sample size of this study. Recurrent urethral obstruction in this study at 30 days was 11%.

Cranial Vena Cava Syndrome in Guinea Pigs with Chronic Jugular Vein Catheters.

Guinea pigs are a premier small animal model for infectious disease research, and chronic indwelling venous access ports may be used to facilitate various procedures. Here we report catheter-related lesions in 5 uninfected Dunkin-Hartley guinea pigs with chronic jugular vein catheters used for imaging studies. Three guinea pigs were found dead with no premonitory signs. At necropsy, there was severe bilateral pulmonary atelectasis due to 20 to 29 mL of pleural effusion resulting from catheter-related thrombosis and cranial vena cava syndrome. In addition, one of these 3 guinea pigs had a polymicrobial catheter infection with abscessation. A 4th clinically normal guinea pig was euthanized at the end of the study, having spontaneously lost its catheter 7 mo prior, and had 17 mL of pleural effusion. The 5th guinea pig was euthanized following pooling of contrast material around the distal catheter in the cranial vena cava on CT. By histology, affected animals had recent and remote thrombosis or fibrosis (or both) of the cranial vena cava and right atrial wall, with osseous and cartilaginous metaplasia. Cranial vena cava syndrome should be considered as a differential for dyspnea or death in chronically catheterized laboratory animals.

Prevalence of and risk factors for intravenous catheter infection in hospitalized cattle, goats, and sheep.

BACKGROUND: Intravenous catheter (IVC) use in hospitalized ruminants is a common procedure. Limited information is available describing complications associated with IVCs. HYPOTHESES: Prevalence of IVC infections in hospitalized ruminants is >50%. Intravenous catheters maintained for >5 days are more likely to be infected than those maintained for <5 days. Intravenous catheters placed non-aseptically have a higher risk for infection than those placed aseptically. ANIMALS: Thirty-four cattle, 39 goats, and 33 sheep were hospitalized in a university teaching hospital. METHODS: Prospective observational study. The IVCs from cattle, goats, and sheep admitted for medical and surgical procedures were randomly selected and submitted for bacteriological culture and susceptibility testing. RESULTS: Prevalence values (95% confidence interval) of infected catheters were 61.8 (45.5, 78.1), 51.3 (35.3, 66.7), and 42.4% (25.2, 58.8) in cattle, goats, and sheep, respectively. Coagulase-negative Staphylococcus spp was the most frequently isolated bacterium. Catheter type/placement technique was a significant (P = .03) predictor of IVC infection in goats but not in cattle (P = .65) and sheep (P = .47). Antibiotic use and reason for catheter placement were not significant predictors of IVC infection in all species. Catheters maintained for >4 days had a higher likelihood of being infected than those maintained for <4 days in all species. CONCLUSIONS AND CLINICAL IMPORTANCE: Clinicians should consider replacing catheters maintained for >4 days to reduce IVC infection.

Thoracoscopic pericardiectomy associated with fully implantable catheter via thoracoscopy in the management of mesothelioma in a bitch.

Mesothelioma is a very aggressive malignant tumor with low survival rates that is often diagnosed belatedly. Pericardial effusion is a common consequence in cases of mesothelioma, with pericardiocentesis and pericardiectomy indicated; therefor thoracocentesis is necessary to drain the contents no longer retained in the pericardium. The present report describes a mesothelioma-carrying dog with a history of cardiac tamponade that underwent thoracoscopic pericardiectomy and, later, thoracoscopic implantation of a fully implantable catheter to function as a thoracic drain. In the consulted literature, there is no use of a fully implantable catheter for this purpose. The authors consider that there was an improvement in the quality of life.

Incidence of arterial catheter complications: a retrospective study of 35 cats (2010-2014).

OBJECTIVES: The aim of this study was to investigate the incidence of complications associated with arterial catheterization in cats in a veterinary hospital, and to document which factors may increase the incidence of complications. METHODS: Medical records at a referral veterinary hospital were retrospectively reviewed to identify cats that had an arterial catheter placed between January 2010 and October 2014. RESULTS: Thirty-five cats having 38 arterial catheters were included in the study. There was a relatively high incidence of minor complications (23.7%), with the most common being catheter occlusion. The incidence of major arterial catheter complications was low (2.63%). Duration of catheter use was positively correlated to the incidence of complications. There was also a significant correlation between catheters used for intensive care unit monitoring and incidence of complications. All cats with catheter complications survived to discharge. CONCLUSIONS AND RELEVANCE: The low incidence of major arterial catheter complications in this population of cats illustrates that arterial catheterization is a safe monitoring and diagnostic tool. The duration of catheter placement is significantly associated with the incidence of catheter complications.

Intracranial pressure monitoring in normal dogs using subdural and intraparenchymal miniature strain-gauge transducers.

BACKGROUND: Monitoring of intracranial pressure (ICP) is a critical component in the management of intracranial hypertension. Safety, efficacy, and optimal location of microsensor devices have not been defined in dogs. HYPOTHESIS/OBJECTIVE: Assessment of ICP using a microsensor transducer is feasible in anesthetized and conscious animals and is independent of transducer location. Intraparenchymal transducer placement is associated with more adverse effects. ANIMALS: Seven adult, bred-for-research dogs. METHODS: In a prospective investigational study, microsensor ICP transducers were inserted into subdural and intraparenchymal locations at defined rostral or caudal locations within the rostrotentorial compartment under general anesthesia. Mean arterial pressure and ICP were measured continuously during physiological maneuvers, and for 20 hours after anesthesia. RESULTS: Baseline mean ± SD values for ICP and cerebral perfusion pressure were 7.2 ± 2.3 and 78.9 ± 7.6 mm Hg, respectively. Catheter position did not have a significant effect on ICP measurements. There was significant variation from baseline ICP accompanying physiological maneuvers (P < .001) and with normal activities, especially with changes in head position (P < .001). Pathological sequelae were more evident after intraparenchymal versus subdural placement. CONCLUSIONS AND CLINICAL IMPORTANCE: Use of a microsensor ICP transducer was technically straightforward and provided ICP measurements within previously reported reference ranges. Results support the use of an accessible dorsal location and subdural positioning. Transient fluctuations in ICP are normal events in conscious dogs and large variations associated with head position should be accounted for when evaluating animals with intracranial hypertension.

Evaluation for association between indwelling urethral catheter placement and risk of recurrent urethral obstruction in cats.

OBJECTIVE To test for an association between indwelling urethral catheter placement in cats with urethral obstruction (UO) and the short-term (30-day) risk of recurrent urethral obstruction (RUO). DESIGN Prospective cohort study. ANIMALS 107 client-owned male cats with UO. PROCEDURES Owners were offered standard care for their cats, including hospitalization, placement of an indwelling urethral catheter, IV fluid therapy, and other supportive treatments (inpatient group). One-time catheterization and outpatient care were offered (outpatient group) if standard care was declined. Data regarding signalment, measures of metabolic compromise and urinalysis findings at enrollment, catheterization-related variables, and supportive treatments of interest were collected. Risk of RUO ≤ 30 days after urethral catheter removal was determined for the outpatient vs inpatient group by OR and 95% confidence interval calculation. Other variables were compared between cats that did and did not develop RUO with Fisher exact and trend tests. RESULTS 91 cats completed the study; 19 (5/46 [11%] inpatients and 14/45 [31%] outpatients) developed RUO. Risk of RUO was significantly greater for cats of the outpatient group (OR, 3.7; 95% confidence interval, 1.2 to 11.4). Among inpatients, increasingly abnormal urine color at the time of catheter removal was significantly associated with RUO. No other significant associations were identified. CONCLUSIONS AND CLINICAL RELEVANCE Hospitalization and indwelling catheterization significantly reduced the risk for RUO ≤ 30 days after treatment for the population studied. Results suggested that removal of an indwelling catheter before urine appears grossly normal may be associated with development of RUO. One-time catheterization with outpatient care was inferior to the standard care protocol but was successful in many cats and may be a reasonable alternative when clients cannot pursue standard care.

Hemodialysis catheter-associated fibrin sheath in a dog.

OBJECTIVE: To describe an intravascular fibrin sheath associated with a hemodialysis catheter in a dog. CASE SUMMARY: A 4-year-old dog presented for hemodialysis to treat acute kidney injury. Hemodialysis catheter dysfunction during the course of treatment was temporarily alleviated using a tissue plasminogen activator. A thrombus composed of fibrin and granulation tissue creating a sheath around the catheter and focally adherent to the vessel wall was identified on postmortem evaluation. NEW OR UNIQUE INFORMATION PROVIDED: Fibrin sheath formation is a commonly recognized problem of central venous catheters used for hemodialysis in people and is likely a common problem in veterinary patients undergoing dialysis as well. This report provides a description of the clinical features of the catheter dysfunction, response to treatment, postmortem radiographic and direct imaging, and histology of the fibrin sheath, and also provides a brief review of potential management techniques that have been described in people.