Evaluation of the placement and maintenance of central venous jugular catheters in critically ill dogs and cats

Suspected Primary Spontaneous Asymptomatic Pneumothorax in a Cat

Spontaneous pneumothorax (SPT) is a documented emergency of the respiratory tract condition classified as either primary or secondary based on the presence of underlying pulmonary conditions. All reported SPT in the feline literature are evaluated for respiratory clinical signs. Primary SPT without underlying pathology or without clinical signs is not reported in cats. This case report describes a 10-year-old domestic longhair cat that was referred for evaluation of chronic lethargy with severe azotemia and placement of a subcutaneous ureteral bypass (SUB) system. Prior to presentation, the cat was diagnosed with renal insufficiency and treated medically with no resolution. Clinical examination under sedation revealed right-sided renomegaly. Thoracic radiographs revealed gas in the caudodorsal pleural space and concurrent pulmonary atelectasis. No respiratory clinical signs were present. Thoracic CT showed two pulmonary bullae, one located in the right caudal lung lobe and one in the cranial segment of the left cranial lung lobe. Abdominal ultrasound showed a right-sided ureteral obstruction. Medical management was elected for the spontaneous pneumothorax. A SUB was placed to address the ureteral obstruction; no complications were noted during recovery. The cat was free of clinical signs of respiratory disease after a follow-up time of nine months. This is the first reported case of a cat diagnosed with a nonclinical suspected primary spontaneous pneumothorax with no concurrent predisposing pulmonary pathology.

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.

Extracorporeal Therapies in the Emergency Room and Intensive Care Unit

Extracorporeal treatments create opportunity for removing disease causing solutes within blood. Intoxications, renal failure, and immune-mediated diseases may be managed with these treatments, often providing new hope for patients with severe or refractory disease. Understanding solute pharmacokinetics and the limitations of each type of extracorporeal technique can allow for the selection of the optimal treatment modality.

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.

Bacterial colonization of non-permanent central venous catheters in hemodialysis dogs

Non-permanent central venous catheters (CVCs), are the most commonly used vascular access in veterinary patients undergoing hemodialysis. In human dialysis patients, CVC infection represents a common cause of morbidity and mortality. The aim of this retrospective observational study was to evaluate the prevalence of bacterial colonization of CVCs in dogs submitted to hemodialysis treatment at time of CVC removal.

The CVCs of all dogs submitted to hemodialysis (n = 23) at the Veterinary Teaching Hospital ''Mario Modenato'' of the University of Pisa between January 2015 and December 2016 were considered. For all dogs, data regarding signalment, reason for hemodialysis treatment, duration of catheterization (≤15 or >15 days), CVC complications, and 30-day survival were considered. Statistical analysis was performed using Graph Pad Prism™. Five over 23 dogs (22%) showed positive bacterial culture of CVC (+), and 18/23 dogs (78%) negative culture of CVC (-). The most prevalent microorganism was Staphylococcus Spp (3/5; 60%). No significant difference was found in the prevalence of CVC infection according to age, gender, reason for hemodialysis, CVC complications, duration of catheterization, and outcome. No statistically significant difference (p = 0.64) in survival curves was reported at log rank analysis between dogs with CVC - and CVC +.

The prevalence of bacterial CVC contamination in our dialysis dogs showed relatively low. Exclusive use of CVC for hemodialysis, good hygiene practice during CVC management, and use of chlorhexidine as an antiseptic should be strongly encouraged.

Comparison of heparinized saline and 0.9% sodium chloride for maintaining central venous catheter patency in healthy dogs

BACKGROUND

The purpose of this study was to determine whether heparinized saline (HS) would be more effective in maintaining the patency of central venous catheters (CVCs) in dogs compared to 0.9% sodium chloride. This was a prospective randomized blinded study conducted at a University Veterinary Teaching Hospital.

METHODS

A total of 24 healthy purpose-bred dogs were randomized into two groups: a treatment and a control group. A CVC was placed in the jugular vein of each dog. Each dog in the treatment group had their CVC flushed with 10 IU/mL HS, while dogs in the control group had their CVC flushed with 0.9% sodium chloride every 6 h for 72 h. Immediately prior to flushing, each catheter was evaluated for patency by aspiration of blood. The catheter site was also evaluated for phlebitis, and a rectal temperature was obtained in each dog every 6 h. Prothrombin (PT) and activated partial thromboplastin (aPTT) times were evaluated prior to the administration of any flush solution. Results were then compared to values obtained 72 h later.

RESULTS

All CVCs in both groups were patent after 72 h, which was demonstrated by aspiration of blood and ease of flushing the catheter. Two CVCs in the 0.9% sodium chloride group had a negative aspiration at hour 12 and 36, respectively. One CVC in the HS group had a negative aspiration at hour 18. Signs of phlebitis occurred in three dog: two in the 0.9% sodium chloride group and one in the HS group. No dog was hyperthermic (>103 °F). Two catheters were inadvertently removed by dogs in the HS group during the study. There were no significant differences in catheter patency, incidence of phlebitis, or incidence of negative aspirations between both groups. aPTT and PT values remained within the normal reference range for all dogs in both groups. Ultimately, 0.9% sodium chloride was as effective as 10 IU/mL HS in maintaining the patency of CVCs for up to 72 h in healthy dogs. Further evaluation in clinical patients is warranted.