Length of hospitalization, APPLE score, and number of intravenous catheters placed at admission are associated with increased odds of peripheral intravenous catheter complications in dogs.

OBJECTIVE: To identify risk factors associated with peripheral intravenous catheter (PIVC) complications in dogs hospitalized in the critical care unit (CCU). ANIMALS: 107 dogs admitted to the CCU between October 2022 and March 2023. METHODS: This prospective, observational clinical trial was performed at a single veterinary teaching hospital. Dogs hospitalized in the CCU for at least 24 hours were evaluated for enrollment. PIVC were placed following a standardized protocol and monitored for complications. PIVC complications were classified as extravasation, phlebitis, dislodgement, occlusion, line breakage, or patient removal. RESULTS: Median PIVC dwell time was 46.50 hours (range, 24.25 to 159.25 hours). Overall PIVC complication rate was 12.1% (13/107), with phlebitis (4/107 [3.7%]) and extravasation (4/107 [3.7%]) being the most frequently recorded complications. Multivariable analysis identified increasing length of hospitalization (LOH; OR, 1.43; 95% CI, 1.04 to 1.97; P = .029), an acute patient physiologic and laboratory evaluation full (APPLEFULL) score > 35 (OR, 4.66; 95% CI, 1.09 to 19.90; P = .038), and having 2 PIVCs placed at admission (OR, 10.92; 95% CI, 1.96 to 60.73; P = .006) as risk factors for PIVC complication. CLINICAL RELEVANCE: Increasing LOH, an APPLEFULL score > 35 and having 2 PIVCs placed at admission were associated with increased odds for PIVC complication in this study. Although these are independent risk factors for PIVC complication, the combination of increasing LOH, an APPLEFULL score > 35, and having 2 PIVCs placed at admission may represent a more severely ill population, drawing attention to a vulnerable group of dogs at risk for PIVC complication.

ARTERIAL CATHETERIZATION IN GREAT APES.

Anesthesia is frequently required to provide appropriate medical care to captive great apes. Anesthetic safety can be optimized through placement of an arterial catheter, which allows direct measurement of arterial blood pressure and easy sampling of arterial blood for blood-gas analysis. Arterial catheterization in great apes can be achieved through palpation-guided or ultrasound-guided placement with or without a modified Seldinger technique. Potential sites for arterial catheterization include the anterior tibial artery, caudal tibial and posterior saphenous arteries, dorsal pedal artery, femoral artery, radial artery, and brachial artery. Arterial catheterization is recommended for lengthy great ape anesthetic procedures or those involving invasive procedures.

Microorganism colonization of peripheral venous catheters in a small animal clinical setting.

OBJECTIVE: To compare the incidence of microorganism colonization of peripheral venous catheters (PVCs) placed in the Emergency Department (ED) to those placed in a routine preoperative setting. The relationship between catheter tip colonization and patient urgency (as assessed by triage priority) was also evaluated. DESIGN: Prospective, observational study from January 2021 to October 2021. SETTING: Emergency room and clinical areas of a large, urban, tertiary referral center. ANIMALS: Three hundred dogs and 94 cats with a PVC in place for a minimum of 24 hours were enrolled in the study. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two hundred and eighty-eight PVCs were placed in the ED and 106 were placed preoperatively. The overall colonization rate was 10.4% (41/394). Sixteen bacterial and 1 fungal genera were cultured. Eight of these bacterial genera (25/51 [49%] bacterial isolates) were resistant to at least 1 antimicrobial class. Twenty-nine of 288 (10.1%) catheters positive for colonization were placed in the ED, whereas 12 of 106 (11.3%) were placed preoperatively. There was no association between microorganism growth on catheters and clinical area of catheter placement. There was also no association between ED patient urgency and positive catheter tip culture. No significant risk factors were identified predisposing to colonization of PVCs. CONCLUSIONS: The overall incidence of microorganism colonization of PVCs in this study population was equivalent to, or lower than, previously reported in veterinary literature. There was no statistical difference between the catheters placed in the ED and those placed for routine surgical procedures. Patient urgency did not affect the incidence of positivity of peripheral catheter tip cultures.

Transillumination facilitates coccygeal arterial cannulation in anaesthetised small-breed dogs.

BACKGROUND: Arterial access in small-breed dogs is challenging, but arterial visualisation may facilitate the procedure, as evidenced in human medicine. This prospective, randomised study investigated the result of using transillumination to guide coccygeal artery cannulation in small-breed dogs. METHODS: Coccygeal artery cannulation was attempted in dogs anaesthetised with butorphanol, midazolam, propofol and sevoflurane. In 70 dogs (standard technique group [STECHNIQUE group]), arterial cannulation was performed using pulse palpation. In 71 dogs (transilluminating-standard technique group [TSTECHNIQUE group]), a transilluminating device was utilised. The device was placed on the dorsal tail, and the cannula was advanced towards the dark line visible against the bright background. If the artery was not well visualised due to pigmentation, pulse palpation was used. The success rate of arterial cannulation was compared between the groups using the chi-squared test. RESULTS: Arterial cannulation was significantly more successful (p < 0.001) in the TSTECHNIQUE group (63/71 [88.7%]) than in the STECHNIQUE group (43/70 [61.4%]). LIMITATIONS: The number of punctures attempted and the time to cannulation were not assessed, and the procedure was only performed by veterinarians experienced in arterial cannulation. CONCLUSIONS: The transillumination allows for a more accurate approach to the coccygeal artery, improving the success of arterial cannulation when combined with pulse palpation.

Retrospective evaluation of intravenous catheterization in client-owned lizards at a veterinary teaching hospital: 21 cases (2018-2021).

OBJECTIVE: To assess the prevalence of lizards presenting to a university teaching hospital that had an IV catheter placed, the catheterization sites used, and complications arising with the placement of the catheter both in the short and long term. DESIGN: Retrospective study. SETTING: University teaching hospital. ANIMALS: Twenty-one lizards, including inland bearded dragons (Pogona vitticeps; 15/21), green iguanas (Iguana iguana; 4/21), and veiled chameleons (Chamaeleo calyptratus; 2/21). INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of 129 lizard consultations performed between September 27, 2018 and September 27, 2021, 21 catheters were placed, resulting in an overall prevalence of 16.3%. Reasons for catheter placement included hospitalization for fluid therapy (10/21 [47.6%]), anesthesia or surgery ± hospitalization (7/21 [33.3%]), computed tomography scan with contrast (2/21 [9.5%]), euthanasia only (1/21 [4.8%]), and CPR only (1/21 [4.8%]). All catheters were placed in the ventral coccygeal vein via a ventral approach. Sedation was used in 6 of 21 (28.6%) of the catheters placed. Seven of the catheters (35%) were used for administration of fluids only, 4 (20%) were used for administering drugs/medications only, and 9 (45%) catheters administered both fluids and drugs/medications. No complications were noticed in any of the lizards that had catheters placed, both in the short and long term. CONCLUSIONS: Based on the retrospective evaluation of medical records at a veterinary teaching hospital, IV catheter placement in lizards is feasible, including in conscious animals, with roughly 1 consultation out of 6 resulting in a catheter placed. The most frequent reason for catheter placement was for administration of fluids.

Incidence and type of peripheral intravenous catheter complications documented in hospitalised dogs.

OBJECTIVE: To report the incidence and type of peripheral intravenous catheter complications in hospitalised dogs. METHODS: A prospective, observational trial was performed. Peripheral intravenous catheters were monitored for complications. Complications were documented and classified as extravasation, phlebitis, dislodgement, occlusion and line breakage. If phlebitis was present, the Visual Infusion Phlebitis Scale was used to assign a grade (0 to 5). Fisher's exact test was used to compare the type of complications between the critical care unit and the intermediate care unit. A univariate logistic model was used to compare the incidence of complications between the critical care unit and the intermediate care unit and adjusted odds ratios were used to compare the groups. RESULTS: The incidence of peripheral intravenous catheter complications was 24.2% in the Critical Care Unit and 13.1% in the Intermediate Care Unit, with an overall incidence of 19.9%. Phlebitis was the most common peripheral intravenous catheter complication in the Critical Care Unit, and line breakage was the most common complication in the Intermediate Care Unit. Length of hospitalisation and weight had a significant effect on the likelihood of complication. In a multivariable logistic regression model, the odds of a peripheral intravenous catheter complication was not significantly higher in CCU than IMCU, accounting for length of hospitalisation and weight (adjusted odds ratio, 1.84; 95% confidence interval, 0.98 to 3.48). CLINICAL SIGNIFICANCE: Peripheral intravenous catheter complications are common in hospitalised dogs and may result in an increased expense for owners, failure to deliver prescribed treatments, venous depletion (lack of peripheral vessels for intravenous catheter placement) and pain experienced by the patient. Techniques to reduce peripheral intravenous catheter complications should be further evaluated and may include the use of peripheral intravenous catheter placement and maintenance checklists, use of force-activated separation devices, or patient sedation.

Fewer peripheral intravenous catheter complications in hospitalized dogs when force-activated separation devices are used versus not used in a randomized controlled clinical trial.

OBJECTIVE: To determine whether the use of a force-activated separation device (FASD) lowers the incidence risk of peripheral intravenous catheter (PIVC) complications in hospitalized dogs. ANIMALS: 367 dogs that were hospitalized and received IV fluids between January 11 and March 25, 2021. PROCEDURES: A prospective, randomized controlled clinical trial was performed. Dogs hospitalized and receiving IV fluids for at least 24 hours were randomized to the FASD group or control group. PIVCs were placed following a standardized protocol. Dogs in the FASD group had the FASD device attached to their PIVC according to manufacturer instructions. For both groups, all PIVC complications were documented, and each complication was classified as extravasation, phlebitis, dislodgement, occlusion, or line breakage. RESULTS: Results from 367 dogs (FASD group = 180, control group = 187) underwent analysis. The proportion of PIVC complications was significantly (P = .004) lower for the FASD group (8.9% [16/180]) versus the control group (24.6% [46/187]). Following adjustment for differences in hospitalization time, the odds of a dog in the FASD group having a PIVC complication was approximately one-third the odds of those in the control group (OR, 0.33; 95% CI, 0.17 to 0.63; P = .001). CLINICAL RELEVANCE: Results indicated that the use of a FASD in hospitalized dogs receiving IV fluids is warranted to lower the incidence of PIVC complications and may also limit patient discomfort, owner expense, and staff time devoted to managing PIVC complications. Further research investigating its use in cats and other species should be considered.

Effect of preemptive topical application of lidocaine or prilocaine-lidocaine on successful catheterization of ear veins in New Zealand White rabbits.

OBJECTIVE: To compare 5% lidocaine ointment applied for 10 minutes before intravenous (IV) catheterization to a eutectic mixture of local anesthetics (2.5% lidocaine and 2.5% prilocaine; EMLA) cream applied for 10 or 60 minutes prior and a water-based placebo for 60 minutes for successful marginal ear IV catheterization in rabbits. STUDY DESIGN: Randomized, blinded, complete crossover, controlled trial. ANIMALS: A total of 10 intact male, New Zealand White rabbits aged 4 months. METHODS: After application of one of the treatments on the marginal ear vein, an operator unaware of the treatment attempted IV catheter placement. Successful IV catheterization was considered as a catheter inserted at the first attempt, safely secured, with appropriate patency. Generalized linear mixed models were developed to identify relevant predictors of successful catheter placement. RESULTS: Ears that had EMLA cream applied 60 minutes before the catheterization attempt had more than 10 times the odds of successful catheter placement [odds ratio (OR)=10.75; 95% confidence interval (CI), 1.92-60.16; p < 0.008] compared with placebo. Both the application of EMLA cream or lidocaine ointment 10 minutes before the catheterization attempt resulted in approximately three times the odds of successful catheter placement compared with placebo, but were not statistically significant. CONCLUSIONS AND CLINICAL RELEVANCE: Application of EMLA cream on the marginal ear vein 60 minutes before catheterization increases the chance of successful IV catheter placement in conscious rabbits.

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.

Peripheral Intravenous Catheter Complications in Hospitalized Cats: An Observational Pilot Study.

OBJECTIVES: There is little information about complications associated with peripheral catheter use in cats. The primary objective of this study was to determine the main reason for catheter removal in cats hospitalized in the Intensive Care Unit at a university teaching hospital. The secondary objective was to describe catheter-associated complications in cats hospitalized. METHODS: All feline patients with peripheral intravenous catheters admitted to the Intensive Care Unit between June and August 2017 were prospectively enrolled in this study. All catheters were evaluated at least 3 times a day per institutional Intensive Care Unit protocol. The catheters were monitored throughout the cat's hospitalization period for development of complications, including occlusion, phlebitis and extravasation. Data collected included patient signalment, reason for hospitalization, catheter size and location, number of hours the catheter remained in place, reason for removal and if the catheter was replaced once removed. RESULTS: Thirty-four cats were enrolled in the study, and a total of 42 catheters were placed in those cats. Median peripheral IV catheter duration was 23.8 hours (interquartile range [IQR] 13.8-41.3 hours). The most frequent reason for catheter removal was patient discharge from the hospital (24/42, 57.1%). Overall catheter complication rate was 21.4% (9/42). Complications observed included phlebitis, extravasation, patient removal, occlusion, and edema formation. CLINICAL SIGNIFICANCE: The results of this study conclude that the majority of peripheral IV catheters in cats are removed due to discharge from hospitalization. More studies with a larger population of cats are needed to see if there is a relationship between length of indwelling catheterization and risk of catheter-associated complications.

Effects of cuff size and position on the agreement between arterial blood pressure measured by Doppler ultrasound and through a dorsal pedal artery catheter in anesthetized cats.

OBJECTIVE: To compare the effects of cuff size/position on the agreement between arterial blood pressure measured by Doppler ultrasound (ABPDoppler) and dorsal pedal artery catheter measurements of systolic (SAPinvasive) and mean arterial pressure (MAPinvasive) in anesthetized cats. STUDY DESIGN: Prospective study. ANIMALS: A total of eight cats (3.0-3.8 kg) for neutering. METHODS: During isoflurane anesthesia, before surgery, changes in end-tidal isoflurane concentrations and/or administration of dopamine were performed to achieve SAPinvasive within 60-150 mmHg. Cuff sizes 1, 2 and 3 (bladder width: 20, 25 and 35 mm, respectively) were placed on distal third of the antebrachium, above the tarsus and below the tarsus for ABPDoppler measurements. Agreement between ABPDoppler and SAPinvasive or between ABPDoppler and MAPinvasive was compared with reference standards for noninvasive blood pressure devices used in humans and small animals. RESULTS: Mean bias and precision (±standard deviation) between ABPDoppler and SAPinvasive met veterinary standards (≤10 ± 15 mmHg), but not human standards (≤5 ± 8 mmHg), with cuffs 1 and 2 placed on the thoracic limb (7.4 ± 13.9 and -5.8 ± 9.5 mmHg, respectively), and with cuff 2 placed proximal to the tarsus (7.2 ± 12.4 mmHg). Cuff width-to-limb circumference ratios resulting in acceptable agreement between ABPDoppler and SAPinvasive were 0.31 ± 0.04 (cuff 1) and 0.42 ± 0.05 (cuff 2) on the thoracic limb, and 0.43 ± 0.05 (cuff 2) above the tarsus. ABPDoppler showed no acceptable agreement with MAPinvasive by any reference standard. CONCLUSIONS AND CLINICAL RELEVANCE: The agreement between ABPDoppler and SAPinvasive can be optimized by placing the occlusive cuff on the distal third of the antebrachium and above the tarsus. In these locations, cuff width should approach 40% of limb circumference to provide clinically acceptable estimations of SAPinvasive. Doppler ultrasound cannot be used to estimate MAPinvasive in cats.

The effects of lidocaine-prilocaine cream on responses to intravenous catheter placement in cats sedated with dexmedetomidine and either methadone or nalbuphine.

OBJECTIVE: To compare the reaction to cephalic intravenous (IV) catheter placement with or without lidocaine-prilocaine cream in cats sedated with dexmedetomidine and methadone or nalbuphine. STUDY DESIGN: Prospective, randomized, blind study. ANIMALS: A group of 24 female mixed breed cats. METHODS: Cats were randomly allocated to one of the two sedation protocols: dexmedetomidine (0.01 mg kg-1) and methadone (0.3 mg kg-1; DEXMET) or dexmedetomidine (0.01 mg kg-1) and nalbuphine (0.3 mg kg-1; DEXNALB). Sedation was scored 30 minutes later using a visual analog scale. Subsequently, a 2 × 3.5 cm area of the antebrachium over the cephalic vein was clipped, and half the cats within each protocol were randomly assigned for topical lidocaine-prilocaine cream (treatment), whereas no cream was applied to other cats (control). After 20 minutes, an attempt was made to place a 24 gauge catheter into the cephalic vein and the reaction of the cats to this procedure was scored using a numeric scale 0-3. Sedation and catheterization reaction scores were compared between sedation protocols and whether cats were administered lidocaine-prilocaine cream or not using the Friedman test followed by the Bonferroni procedure. A p value < 0.05 was considered significant. RESULTS: Sedation scores were not different between sedation protocols or between treatment and control cats within each protocol. All cats administered lidocaine-prilocaine cream showed no reaction to IV catheter placement. Among the control cats, no response was observed in one cat in DEXNALB. Catheterization reaction score was lower in the treatment cats in both the sedation protocols when compared with their respective controls. CONCLUSIONS AND CLINICAL RELEVANCE: Lidocaine-prilocaine cream applied for 20 minutes abolished the reaction to catheterization in cats sedated with dexmedetomidine and nalbuphine or methadone. Facilitation of IV catheter placement occurred within 20 minutes of lidocaine-prilocaine application.

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.

The clinical efficacy of EMLA cream for intravenous catheter placement in client-owned dogs.

OBJECTIVE: To assess the reaction of client-owned dogs to intravenous (IV) catheter placement after applying a local anaesthetic (EMLA) or placebo cream for either 30 or 60 minutes. STUDY DESIGN: Prospective, randomized, blinded, placebo-controlled, clinical trial. ANIMALS: A total of 202 client-owned dogs of various breeds. METHODS: With owner consent, dogs were randomly allocated to one of four treatment groups: EMLA 60 minutes, EMLA 30 minutes, Placebo 60 minutes and Placebo 30 minutes. After the cream was applied for the allocated time, an IV catheter was placed and the behavioural reaction of the dog was scored. The reaction score was analysed using a Kruskal-Wallis test followed by Mann-Whitney U tests of the multiple pairwise comparisons, with Bonferroni correction. RESULTS: A large number of dogs, even in the placebo groups, did not react to IV catheter placement. However, the Kruskal-Wallis test showed an overall difference between treatment groups (χ2 = 11.029, df = 3, p = 0.012). The pairwise comparisons showed a lower overall reaction score in the EMLA 60 group than in the EMLA 30 and Placebo 60 groups (adjusted p = 0.018 and adjusted p = 0.044, respectively). CONCLUSIONS AND CLINICAL RELEVANCE: This study shows that EMLA cream applied for 60 minutes reduces the behavioural reaction of dogs to IV catheter placement; therefore, this intervention can be advocated for routine use in veterinary medicine to enhance the welfare of dogs undergoing IV catheter placement.

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.

Complications of intravenous catheterization in horses.

INTRODUCTION: Intravenous catheterization is a necessity for continuous administration of intravenous fluids and for intermittent intravenous access to avoid discomfort and potential complications of repeated needle insertions into the vein. Intravenous catheterization is commonly performed and well tolerated in horses, but catheter associated complications have been reported. The most commonly reported complication is thrombophlebitis, but others such as venous air embolism, exsanguination and catheter fragmentation may also occur. This article aims to review clinical signs, pathogenesis, diagnosis, therapy, risk factors and prevention of common catheter associated complications.

INTRODUCTION: Le cathétérisme veineux est une nécessité pour l'administration continue de fluides par voie intraveineuse et pour garantir un accès veineux intermittent afin d'éviter l'inconfort et les complications potentielles liées à la pénétration répétée d'une aiguille dans la veine. Le cathétérisme veineux est usuellement pratiqué chez le cheval et il est bien toléré mais des complications associées sont rapportées. La plus commune d'entre elle est la thrombophlébite mais d'autre, telles l'embolie gazeuse, l'exsanguination ou la fragmentation du cathéter peuvent aussi survenir. Cet article vise à résumer les signes cliniques, la pathogénèse, le diagnostic, le traitement les facteurs de risque et la prévention des complications communément associées avec le cathétérisme.

A survey of the use of arterial catheters in anesthetized dogs and cats: 267 cases.

OBJECTIVES: To describe the clinical practice of insertion of arterial catheters in anesthetized dogs and cats, to document complications of arterial catheterization, and to determine risk factors associated with the complications. DESIGN: Prospective clinical study and retrospective evaluation of medical records. SETTING: University teaching hospital. ANIMALS: Dogs (n = 251) and 13 cats anesthetized for clinical procedures with arterial catheters inserted for blood pressure monitoring. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Details of the animal and catheter were collected at the time of anesthesia. On the following day, the catheter site was palpated and observed for abnormalities and the medical records of all animals were reviewed retrospectively for complications. Details of catheter placement were available for 216 catheters: 158 catheters in a dorsal pedal artery, 50 catheters in the median caudal (coccygeal) artery, 6 in the median artery, and 1 each in a cranial tibial and lingual artery. Blood pressure was obtained from 200 catheters, and 12 catheters failed before the end of anesthesia. Postoperative observational data obtained from 112 catheters described a palpable arterial pulse at 73 sites and no pulse at 21 sites. No risk factor for arterial occlusion was identified. No complications resulting from arterial catheterization were noted in the medical records. CONCLUSIONS: Arterial catheterization resulted in loss of a peripheral pulse postoperatively in 21/94 (22.3%) of animals examined, although no evidence of tissue ischemia was noted in the medical records of any of the patients in this study. These results suggest that insertion of a catheter in the dorsal pedal or coccygeal arteries was not associated with a high risk for complications. However, the course of arterial occlusion postoperatively warrants further investigation.

A description of a technique for ultrasound-guided lumbar plexus catheter in dogs: cadaveric study.

OBJECTIVE: To describe an ultrasound-guided approach for lumbar plexus catheter placement in dogs. STUDY DESIGN: Prospective experimental cadaveric study. ANIMALS: Eleven thawed canine cadavers (13 ± 2 kg). MATERIAL AND METHODS: A technique to place a catheter in the psoas compartment at the level of the lumbar plexus under ultrasound guidance was described. Ultrasonographic landmarks for the placement of a lumbar plexus catheter were identified as the body of the sixth lumbar vertebrae, the psoas muscle and the femoral nerve. All catheters were placed by the principal investigator using epidural sets with an 18-G Tuohy needle. The procedure was carried out twice in each cadaver, with the aim of placing a catheter at the point of the left and right lumbar plexuses. A total volume of 0.4 mL kg(-1) of 1% methylene blue solution was injected into the psoas compartment after which the catheter was removed. After performing the injection in four cadavers, the technique was modified, altering the angle of needle placement and length of catheter insertion. Staining of the femoral and obturator nerves was assessed. Success was recorded if both nerves were stained over a length >1 cm. The spreading of the dye into the abdomen or to the nerve roots was also recorded. RESULTS: The success rate after the first four cadavers was four out of eight, and dye was found in the abdomen of two of the cadavers. When the modified technique was used in the subsequent seven cadavers, the success rate was 12 out of 14, and no dye was found in the abdomens. CONCLUSIONS AND CLINICAL RELEVANCE: This technique has shown a high percentage of success and low rate of complications. The only complication investigated in this study was the spread to the abdomen or epidural space. To establish safety, clinical studies will be needed.

A retrospective evaluation of polyurethane, long-stay, peripheral venous cannulae in dogs undergoing radiotherapy.

OBJECTIVES: The aim of this retrospective study was to review placement duration and associated complications of long-stay, peripheral venous cannulae in dogs undergoing a radiotherapy protocol. Factors affecting duration of stay of the cannulae were evaluated. METHODS: The records of patients which had a single-lumen, 16-gauge, 16-cm polyurethane cannulae inserted into a peripheral vein between 2010 and 2014 were reviewed. RESULTS: Forty-one cannulae were placed in 41 patients. Median duration of cannula stay was 14 days (range 2 to 26). In 14 cases (~34%) the cannula was removed at the end of the radiotherapy course. In 13 (~32%) cases, cannula-related complications resulted in premature removal. Use of steroids and antibiotics appeared to be associated with a longer median duration of stay. CLINICAL SIGNIFICANCE: No life-threatening complications were encountered. Indwelling, polyurethane, saphenous cannulae were an effective and safe way to maintain venous access in this group of patients. Prednisolone and antibiotics were typically commenced for acute radiation side effects -midway through the protocol; therefore their association with length of stay may not be a direct result of their administration.