Long-Term Management of Vascular Access Ports in Nonhuman Primates Used in Preclinical Efficacy and Tolerability Studies.

Vascular access ports (VAPs) are an essential tool for long-term vascular access in preclinical studies and disease modeling in non-human primates (NHPs). We retrospectively reviewed central (inferior vena cava, IVC) and portal VAP implantation with the maintenance at our center from 15 January 2010 to 31 January 2018. In total, 209 VAPs were implanted for long-term drug administration and sampling. Patency was >95% at 6 months and >80% at 1 year for IVC VAPs and >90% at 6 months and >85% at 1 year for portal VAPs. The majority of animals had no complications and access was generally durable with device use ranging up to 7 years. In IVC, VAPs loss of patency occurred in 13% (0.035/100 d), surgical site infection in 2.9% (0.097/100 d), port pocket infection in 2.2% (0.004/100 d), erosion in 2.9%, 0.008/100 d), and mechanical failure in 4.3% (0.012/100 d). In portal, VAPs loss of patency occurred in 11.3% (0.028/100 d) and port pocket infection in 1.4% (0.003/100 d). About 12% of VAPs were removed as a result of complications.This study confirms VAP implant and maintenance is a beneficial and safe practice in NHPs resulting in favorable outcomes. High patency rates and low complication rates are comparable to the clinical setting. In addition to enabling comprehensive data collection, VAPs increase satisfaction and well-being by minimizing interference with daily routines and fostering cooperation. VAP implantation, together with an effective maintenance regimen and co-operative handling, is a reliable and convenient refined method for drug administration and blood sampling.Keywords: Vascular access port; nonhuman primates; refinement; central vascular access; portal vascular access; surgical technique; experimental surgery; animal model.

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.

Effects of the use of silver-coated urinary catheters on the incidence of catheter-associated bacteriuria and urinary tract infection in dogs.

OBJECTIVE To determine the effects of silver-coated versus standard silicone urinary catheters on the incidence of catheter-associated bacteriuria (CAB) and catheter-associated urinary tract infection (CAUTI) in dogs. DESIGN Randomized controlled clinical trial. ANIMALS 36 dogs requiring urinary bladder catheterization for ≥ 24 hours. PROCEDURES Dogs were randomly assigned to receive a silver-coated or non-silver-coated (control) silicone Foley catheter. Urine samples for cytologic examination and bacterial culture were collected at the time of catheter insertion and daily until catheters were removed (≥ 24 hours to 7 days later). Results were compared between groups. RESULTS No significant differences were identified between catheter groups in the incidence of CAB or CAUTI. Although the median time to development of cytologically detected bacteriuria, culture-detected bacteriuria, and CAUTI did not differ significantly between groups, median time to CAB development (either method) was significantly longer for dogs that received a control catheter rather than a silver-coated catheter. For both types of catheters combined, older age was a significant predictor of culture-detected bacteriuria, and longer duration of catheterization was a significant predictor of culture-detected bacteriuria and overall CAB. CONCLUSIONS AND CLINICAL RELEVANCE Silver-coated urinary catheters provided no clinical benefit over standard urinary catheters for the dogs of this study and were associated with earlier development of CAB but not CAUTI. A larger prospective study is required to definitively determine whether the use of silver-coated urinary catheters should or should not be considered to reduce the risk of CAB or CAUTI in dogs.

Incidence of and associated factors for bacterial colonization of intravenous catheters removed from dogs in response to clinical complications.

BACKGROUND: Infection rate associated with intravenous (IV) catheter placement is emerging as an important issue in small animal veterinary medicine, mostly because of the economic costs associated with these infections. Identification of possible associated factors may provide useful information for the surveillance and prevention of such infections. OBJECTIVES: To determine the incidence of positive bacterial cultures obtained from IV catheters used in dogs hospitalized for at least 48 hours and removed because of clinical complication. To identify the bacteria involved and factors associated with bacterial colonization. ANIMALS: One-hundred eighty-two dogs that underwent IV catheterization from January 2015 to July 2015 at the Veterinary Teaching Hospital of Alfonso X el Sabio University of Madrid were enrolled in the study. RESULTS: The bacterial colonization rate of all IV catheters removed in response to clinical complications was 39.6%, the cumulative proportion of catheters that remained in place at 24, 48, and 72 hours after placement was 89.5, 78, and 59.4%, respectively. Multivariable Cox proportional hazards regression indicated significant associations for staff who performed catheterization (junior, P = .002; student, P = .034) and use of steroidal anti-inflammatory drugs (P = .036). The most frequently isolated bacterium was Acinetobacter spp. (21.7%). CONCLUSIONS AND CLINICAL IMPORTANCE: The bacterial colonization incidence related to IV catheter placement was slightly higher than the incidence described in other veterinary studies. Associated factors not previously described in veterinary medicine were found. The most frequently isolated organism was Acinetobacter spp., indicating its importance as an emerging pathogen in catheter colonization.

[Catheter-associated complications in the horse - diagnosis and treatment in practice]. / Katheterassoziierte Venenerkrankungen beim Pferd - Diagnose und Therapie in der Praxis.

Venous diseases due to venous catheters have variable symptoms and clinical progress. They comprise perivenous hematoma, periphlebitis, endophlebitis, phlebothrombosis or septic thrombophlebitis. To diagnose venous disease, a clinical examination (possibillity to distend the vein, swelling, pain, increased skin temperature, and any exudation around the injection site) and an ultrasonographic examination (perivenous tissue, venous wall, venous content) of the vein are performed. Treatment of venous diseases depends on the etiology and pathogenesis and combines the use of anticoagulants (heparin, phenprocoumon), anti-inflammatory and analgesic substances (non-steroidal inflammatory drugs) as well as the application of antibiotics depending on the case. For prevention of venous diseases a careful catheter management is important. This includes in particular the adequate selection of the catheter system (long-term catheter made of polyurethane), catheter care and intensive monitoring. This article reviews the different venous diseases, diagnosis and therapeutic measures in a practical manner.

Evaluation of urinary catheters coated with sustained-release varnish of chlorhexidine in mitigating biofilm formation on urinary catheters in dogs.

BACKGROUND: Biofilm formation occurs commonly on urinary catheters. OBJECTIVES: To assess the efficacy of urinary catheters coated with sustained-release varnish of chlorhexidine in decreasing catheter-associated biofilm formation in dogs. ANIMALS: Thirty client-owned dogs. METHODS: Prospective study. Thirteen dogs were catheterized with urinary catheters coated with sustained-release varnish of chlorhexidine (study group), and 13 dogs were catheterized with an untreated urinary catheter (control group). Presence and intensity of biofilm formation on the urinary catheters were assessed and compared between the groups by evaluating colony-forming units (CFU) of biofilm bacteria, and semiquantitatively, using confocal laser scanning microscopy and electron microscopy. RESULTS: None of the dogs experienced adverse effects associated with the presence of the urinary catheters. Median CFU count of biofilm bacteria at all portions of the urinary catheter was significantly (P < .001) lower in the study compared with the control group. The degree of biofilm formation on the urinary catheters, as evaluated by confocal laser scanning microscopy and electron microscopy, was significantly lower in the study compared with the control group. Electron microscopy examination identified crystals on some of the urinary catheters. The proportion of catheters on which crystals were observed was significantly lower on the distal part of the urinary catheter in the study group compared with the control group (16.7% versus 66.7%, respectively; P = .04). CONCLUSIONS AND CLINICAL IMPORTANCE: Chlorhexidine sustained-release varnish-coated urinary catheters effectively decrease urinary catheter-associated biofilm formation in dogs.

Bacterial and fungal colonisation of peripheral intravenous catheters in dogs and cats.

OBJECTIVES: The purposes of this study were to determine the prevalence of intravenous catheter colonisation in a routine clinical setting, to identify pathogens involved and to explore factors associated with an increased risk of colonisation. METHODS: A prospective study of 100 peripherally placed intravenous catheters from 13 cats and 78 dogs was conducted. The distal two-thirds were removed and submitted for bacterial and fungal cultures. Antimicrobial susceptibility of each isolate was determined. RESULTS: Nineteen peripheral catheters were positive for microbiologic culture from 14 animals. Twenty organisms were isolated among which Staphylococcus species was the most common. Isolates displayed lower levels of resistance against the antimicrobial agents amoxicillin-clavulanate, cephalosporins and gentamicin than against other agents tested. Major risk factors predisposing to catheter-related colonisation included dextrose infusion, duration of catheter placement, local complications and immunosuppressive diseases or drugs. CLINICAL SIGNIFICANCE: In a routine clinical setting, the prevalence of microbial colonisation of peripheral intravenous catheters is comparable to that found in an intensive care unit. However, consequences on morbidity and mortality rates differ.

Surgical treatment of septic jugular thrombophlebitis in nine horses.

OBJECTIVE: To report a technique for surgical treatment of septic jugular thrombophlebitis unresponsive to medical treatment. STUDY DESIGN: Case series. ANIMALS: Horses (n=9) with septic jugular thrombophlebitis unresponsive to medical treatment. METHODS: Jugular vein thrombectomy was performed under standing sedation and local anesthesia. The contents of the affected portion of vein were removed by multiple incisions in the vein, with the incisions left open to drain and heal by second intention. RESULTS: The technique was curative in all instances, although 2 horses required a 2nd procedure. One horse required ligation of the linguofacial vein to control postsurgical hemorrhage. CONCLUSIONS: The technique is an effective surgical treatment for septic jugular thrombophlebitis unresponsive to medical treatment. CLINICAL RELEVANCE: Jugular vein thrombectomy is a straightforward technique, and has minimal postoperative complications. It allows expedient and cost-effective resolution of medically recalcitrant cases of septic jugular thrombophlebitis.

Prospective evaluation of complications associated with jugular venous catheter use in a veterinary hospital.

OBJECTIVES: To prospectively investigate the incidence of mechanical and infectious complications associated with the use of jugular catheters and risk factors for these complications. METHODS: Data was collected over a 6-month period and risk factors associated with the occurrence of mechanical or inflammatory complications were investigated. RESULTS: One hundred catheters were placed over a 6-month period, totalling 393 catheter days. Complications were seen in 39% of catheters with a total of 51 complications. Forty-one of these complications were mechanical. A total of 10 inflammatory or infectious complications were identified in eight catheters (a total of 0.03 infectious complications per catheter day). Complications were more likely to occur in patients requiring more than one attempt for placement and patients that were ASA status 3 to 5. Infectious complications were more likely in patients not having general anaesthesia for placement, those having medical rather than surgical disease and those placed out of theatre. No association was found between the skill of the person placing the catheter and risk of complication. CLINICAL SIGNIFICANCE: Mechanical complications are frequently associated with jugular catheter placement. Identification of risk factors for complications is important and warrants further study.

Assessment of subclinical venous catheter-related diseases in horses and associated risk factors.

A total of 102 horses that had a catheter introduced intravenously to facilitate treatment had the catheterised jugular vein and contralateral vein examined by ultrasound every 48 hours. Subclinical complications were defined by thrombus formation or thickening of the venous wall, and the data were analysed to establish risk factors for the development of these complications. The horses with a rectal temperature above 38.5 degrees C when the catheter was introduced were four times more likely to develop complications, than the horses with a lower temperature. The administration of a NSAID while the catheter was in place reduced the risk of complications developing.