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).

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.

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.

Ultrasound guided spinal catheter insertion in piglet: preliminary results.

OBJECTIVE: To describe the ultrasound (US) evaluation of the cervical, thoracic and lumbar spinal tracts in piglets and to evaluate the feasibility of the ultrasound guided spinal catheter placement in newborn and paediatric piglets. STUDY DESIGN: Prospective experimental study. ANIMALS: A total of two piglet cadavers (age, 7 and 14 days) and eight commercial crossbreed piglets divided into four groups according to age: 7 (P7), 14 (P14), 21 (P21) and 28 (P28) days. METHODS: In the first part of the study an ultrasound examination of the spinal tract was performed in piglet cadavers applying the transverse and the longitudinal approaches in sternal and lateral recumbencies. In the second phase, the piglets were anaesthetized with sevoflurane. A US examination with a 10 MHz linear probe was performed and a spinal catheter was introduced between the spinous processes of L2 and L3 lumbar vertebrae using an in-plane technique and its advancement was monitored with the probe. At the end of procedure, the catheter was removed. The piglets recovered from anaesthesia and were monitored for one week. RESULTS: In phase I the authors identified the paramedian longitudinal approach as the most feasible for spinal structure evaluation in piglets. In phase II, the paramedian longitudinal views enabled a good visualization of the spinal cord and of the catheter advancement up to the cisterna magna in groups P7 and P14. In groups P21 and P28 it was not possible to visualize the neuroaxial structures and the spinal catheter using the same approach. No clinical alterations were recorded during the procedure or the following days. CONCLUSIONS AND CLINICAL RELEVANCE: US-guided spinal catheter placement appeared a feasible technique in piglets younger than 14 days but it is not useful in older piglets.

JUGULAR CENTRAL VENOUS CATHETER PLACEMENT THROUGH A MODIFIED SELDINGER TECHNIQUE FOR LONG-TERM VENOUS ACCESS IN CHELONIANS.

Long-term or repeated venous access in chelonians is difficult to obtain and manage, but can be critically important for administration of medications and blood sampling in hospitalized patients. Jugular catheterization provides the most rapid and secure route for vascular access, but catheters can be difficult to place, and maintaining catheter patency may be challenging. Long multilumen polyurethane catheters provide flexibility and sampling access, and minimize difficulties, such as catheter displacement, that have been encountered with traditional over-the-needle catheters. We describe placement of 4 Fr. 13-cm polyurethane catheters in three chelonians with the use of a modified Seldinger technique. Venous access was obtained with the use of an over-the-needle catheter, which allowed placement of a 0.018-in.-diameter wire, over which the polyurethane catheter was placed. Indwelling time has ranged between 1 and 4 mo currently. All tortoises were sedated for this procedure. Polyurethane central catheters provide safe, long-term venous access that allows clinicians to perform serial blood sampling as well as intravenous administration of medications, anesthetic agents, and fluids. A jugular catheter can also allow central venous pressure measurement. Utilization of central line catheters was associated with improvements in diagnostic efficiency and therapeutic case management, with minimal risks and complications.

Abomasal amino acid infusion in postpartum dairy cows: Effect on whole-body, splanchnic, and mammary amino acid metabolism.

Nine Holstein cows with rumen cannulas and indwelling catheters in splanchnic blood vessels were used in a generalized randomized incomplete block design with repeated measures to study the effect of increased early postpartum AA supply on splanchnic and mammary AA metabolism. At calving, cows were blocked according to parity (second and third or greater) and allocated to 2 treatments: abomasal infusion of water (CTRL; n=4) or free AA with casein profile (AA-CN; n=5) in addition to a basal diet. The AA-CN infusion started with half of the maximal dose at the calving day (1 d in milk; DIM) and then steadily decreased from 791 to 226 g/d until 29 DIM. On 5, 15, and 29 DIM, 6 sample sets of arterial, portal, hepatic, and mammary blood were taken at 45-min intervals. Over the whole period, increasing AA supply increased milk (+7.8 ± 1.3 kg/d) and milk protein yields (+220 ± 65 g/d) substantially. The increased milk yield was not supported by greater dry matter intake (DMI) as, overall, DMI decreased with AA-CN (-1.6 ± 0.6 kg/d). Arterial concentrations of essential AA were greater for AA-CN compared with CTRL. The net portal-drained viscera (PDV) release of His, Met, and Phe was greater for AA-CN compared with CTRL, and the net PDV recovery of these infused AA ranged from 72 to 102% once changes in DMI were accounted for. The hepatic removal of these AA was increased equivalently to the increased net PDV release, resulting in an unaltered net splanchnic release. The net PDV release of Ile, Leu, Val, and Lys tended to be greater for AA-CN, and the net PDV recovery of these infused AA ranged from 69 to 73%, indicating increased PDV metabolism with AA-CN. The fractional hepatic removal of these AA did not differ from zero and was unaffected by the increased supply. Consequently, the splanchnic release of these AA was approximately equivalent to their net PDV release for both CTRL and AA-CN. Overall, greater early postpartum AA supply increased milk and milk protein yields substantially based on increased mammary AA uptake. The PDV metabolism of branched-chain AA and Lys were increased, whereas it seemed to be unaffected for other essential AA when the intestinal AA supply was increased. On a net basis, the liver removed more group 1 AA (His, Met, Phe, and Trp) for anabolism and catabolism when the early postpartum AA supply was increased. Thus, increasing the postpartum AA supply increased splanchnic and mammary consumption of AA; hence, the protein deficiency persisted.

Abomasal amino acid infusion in postpartum dairy cows: Effect on whole-body, splanchnic, and mammary glucose metabolism.

Nine Holstein cows fitted with rumen cannulas and indwelling catheters in splanchnic blood vessels were used to study the effects of supplementing AA on milk lactose secretion, whole-body rate of appearance (WB-Ra) of glucose, and tissue metabolism of glucose, lactate, glycerol, and ß-OH-butyrate (BHBA) in postpartum dairy cows according to a generalized randomized incomplete block design with repeated measures in time. At calving, cows were blocked according to parity (second and third or greater) and were allocated to 2 treatments: abomasal infusion of water (n=4) or abomasal infusion of free AA with casein profile (AA-CN; n=5) in addition to the same basal diet. The AA-CN infusion started with half the maximal dose at 1 d in milk (DIM) and then steadily decreased from 791 to 226 g/d from DIM 2 to 29 to cover the estimated essential AA deficit. On DIM 5, 15, and 29, D[6,6-(2)H2]-glucose (23.7 mmol/h) was infused into a jugular vein for 5h, and 6 blood samples were taken from arterial, portal, hepatic, and mammary sources at 45-min intervals, starting 1h after the initiation of the D[6,6-(2)H2]glucose infusion. Trans-organ fluxes were calculated as veno-arterial differences times plasma flow (splanchnic: downstream dilution of deacetylated para-aminohippurate; mammary: Fick principle using Phe+Tyr). Energy-corrected milk and lactose yields increased on average with AA-CN by 6.4 kg/d and 353 g/d, respectively, with no DIM × treatment interaction. Despite increased AA supply and increased demand for lactose secretion with AA-CN, net hepatic release of glucose remained unchanged, but WB-Ra of glucose tended to increase with AA-CN. Portal true flux of glucose increased with AA-CN and represented, on average, 17% of WB-Ra. Splanchnic true flux of glucose was unaltered by treatments and was numerically equivalent to WB-Ra, averaging 729 and 741 mmol/h, respectively. Mammary glucose utilization increased with AA-CN infusion, averaging 78% of WB-Ra, and increased gradually as lactation advanced. Net portal, hepatic, splanchnic, and mammary fluxes of lactate, glycerol, and BHBA were not affected by AA infusion. Increasing the supply of AA in postpartum dairy cows elevated the WB-Ra of glucose without affecting the true liver glucose release. The greater WB-Ra of glucose with abomasal AA infusion seemed to originate mainly from greater true portal-drained viscera release of glucose. Glucose utilization by the portal-drained viscera was unaffected by abomasal AA infusion, but the exact mechanism behind the greater true portal glucose release could not be assessed in the current study. The increased mammary glucose uptake was in line with the increased milk lactose yield. In early postpartum lactation, the demand for AA seems to be so high that even with increased AA supply, cows have metabolic priorities for AA other than hepatic gluconeogenesis.

Evaluation of regional limb perfusion with erythromycin using the saphenous, cephalic, or palmar digital veins in standing horses.

There are no reported studies evaluating the use of erythromycin for regional limb perfusion (RLP) in horses. Our hypothesis was that using the cephalic and saphenous veins for RLP will enable delivery of therapeutic concentrations of erythromycin to the distal limb. Nineteen healthy horses participated in the study. The cephalic, saphenous or palmar digital (PD) vein was used to perfuse the limb with erythromycin. Synovial samples were collected from the metacarpo/metatarso-phalangeal (MCP/MTP) joint and blood samples were collected from the jugular vein. Maximum concentration (C(max)) of erythromycin in the MCP joint using the cephalic vein was 113 mg/L. The Cmax of erythromycin in the MTP joint using the saphenous vein was 38 mg/L. Erythromycin administered using the PD vein was not detectable in the MCP/MTP joint of four of six horses. Concentrations of erythromycin achieved in the synovial fluid of the MCP/MTP joint were between 152 and 452 times the minimal inhibitory concentration (MIC) for Rhodococcus equi (R. equi). In conclusion, the results indicate that when using the saphenous or cephalic veins for RLP, therapeutic concentrations of erythromycin in the MCP/MTP joint can be consistently reached [corrected].

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.

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.

[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.

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.

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.

Use of the PleuralPort device for management of pleural effusion in six dogs and four cats.

OBJECTIVE: To describe the placement technique, complications, and outcomes associated with use of the PleuralPort device for management of pleural effusion in dogs and cats. STUDY DESIGN: Case Series. ANIMALS: Six dogs and 4 cats. METHODS: Medical records of all animals with pleural effusion managed with the PleuralPort device were reviewed. Data regarding signalment, fluid analysis, placement technique, duration of function, duration of implantation, complications, and outcome were collected. Owners and referring veterinarians were contacted for follow-up information. RESULTS: Nine animals had chylous effusion and 1 dog had pleural carcinomatosis. Eleven ports were placed with 1 cat receiving bilateral ports. Four animals developed complications. One cat developed pneumothorax immediately after implantation and was euthanatized. In 2 dogs and 1 cat, the ports obstructed. The 6 remaining animals had functioning ports at time of death or resolution of effusion and no longer required use of the port. No significant port migration, irritation, or infection of the device was reported. Excluding the cat with pneumothorax, median duration of port function was 20 days (range 1-391), and median duration of port implantation was 391 days (range 6-723). CONCLUSIONS: The PleuralPort device is a feasible option for the management of pleural effusion in dogs and cats.

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.

Technical note: An apparatus for catheterization of the lateral brain ventricle in Holstein cows.

A stereotaxic apparatus for access to the lateral brain ventricle of Holstein cows was constructed. This apparatus permits topographic orientation on the head of an anesthetized cow that has been placed in right lateral recumbency. After assessing the XY-plane in parallel to the frontal bone, correct coordinates in reference to the skullcap were adjusted. The lateral brain ventricles were accessed by drilling holes perpendicular to the XY-plane. The subsequent surgical implant of a tailor-made cannula guide enabled the repeatable placement of a catheter. This permanent catheter allowed the frequent withdrawal of cerebrospinal fluid from and injections into cerebral ventricles of nonanesthetized dairy cows. This method is critical for elucidating the role of central hormones, metabolites, and electrolytes in the regulation of diverse physiological processes and for the study of neuropathological disorders in cows.

Comparison of hematologic and biochemical results on blood obtained by jugular venipuncture as compared with intravenous catheter in adult horses.

BACKGROUND: During hospitalization, horses typically undergo frequent blood sampling for diagnostic testing and monitoring. The need for numerous samples in hospitalized horses makes acquisition from an intravenous catheter (IVC) both convenient and less stressful to the patient. HYPOTHESIS: We hypothesized that there would be no significant difference in the plasma chemistry and CBC variables from blood samples obtained from a jugular catheter as compared with direct jugular venipuncture. ANIMALS: Fifty adult hospitalized horses; 25 receiving constant rate crystalloid therapy, and 25 receiving low volume IV medication. METHODS: This study was conducted using a prospective, blinded, cross-over design. Samples were obtained sequentially by direct venipuncture of the jugular vein and aspiration from an IVC in the contralateral vein after an appropriate presample of blood was obtained and discarded. Samples were submitted for blinded analysis including CBC, plasma chemistry analysis, stall side plasma glucose concentration, PCV, and total protein concentration. Data obtained were analyzed using a Student's t-test with compensation for unequal variances between the 2 groups. Analyses were Bonferroni corrected for a 5% 2-tailed hypothesis test. RESULTS: There were no statistically significant or clinically relevant differences associated with sampling method (venipuncture versus catheter) regardless of fluid administration status in any of the 24 analytes measured. CONCLUSIONS AND CLINICAL IMPORTANCE: Blood samples obtained by IVC have clinically equivalent values to those taken by direct venipuncture in commonly performed analyses. Additional investigation is warranted to establish if this technique is associated with increased complications such as phlebitis or bacteremia.

Complications associated with use of subcutaneous vascular access ports in cats and dogs undergoing fractionated radiotherapy: 172 cases (1996-2007).

OBJECTIVE: To describe complications associated with use of a subcutaneous vascular access port (SVAP) in cats and dogs treated with fractionated radiotherapy and to determine predisposing factors for developing these complications. DESIGN: Retrospective case series. ANIMALS: 46 cats and 126 dogs. PROCEDURES: The medical records of cats and dogs undergoing radiation therapy that received placement of an SVAP between March 1996 and August 2007 were reviewed. Data were recorded and analyzed to determine factors for development of complications associated with the use of an SVAP during treatment with fractionated radiotherapy. RESULTS: 18 and 36 major and minor complications were identified, respectively. Sex and the lack of administration of propofol during anesthesia induction were significantly associated with development of major complications. Female cats and dogs were 5.00 times as likely as male cats and dogs to develop major complications associated with SVAP usage. Animals in which propofol was not administered were 19.15 times as likely as animals administered propofol to develop major complications. Placement of SVAP catheters in a femoral vein was 17.20 times as likely as placement in the jugular vein to result in minor complications. CONCLUSIONS AND CLINICAL RELEVANCE: Factors associated with the development of complications included sex, propofol administration, and vein in which an SVAP catheter was inserted. The use of an SVAP may be a useful alternative to repeated catheterizations in cats and dogs.

Surgical vascular access in the porcine model for long-term repeated blood sampling.

A simple technique for implanting a long-term jugular catheter in piglets under general anesthesia is described. We report our experience in 10 young female pigs with a body weight of 20-30 Kg. The surgical procedure involves implantation of a jugular central venous catheter (11Fr polyurethane) tunneled in the subcutaneous fat layer of the neck. This procedure may be performed in about 15 minutes. The maintenance of the catheter is described which allows several daily blood samples to be taken. This procedure reduces both the stress in piglets and the chance of catheter dislodgement due to the animals scratching or rubbing. Blood sampling can be easily performed with a low incidence of infection or thrombosis.