Animal Care Products/3M, St. Paul, Minnesota). The injection cap was left ... Popovic V, Popovic P. Permanent cannulation of aorta and vena cava in rats and ground ... Lippert AC, Faulkner JE, Evans AT,Mullaney TP. Total parenteral nutrition ...
A method for chronic intravenous catheterization in the cat Susan M. Cochrane, Joane M. Parent, Dana G. Allen, William D. Black, Anne E. Valliant, John H. Lumsden Easy access to a vein for either repeat sampling or treatment is frequently desirable in the cat. The stress associated with excessive handling in this species can potentially alter laboratory results or harm a debilitated patient (1). A number of approaches have been used for repeated collection of blood in the cat. These include multiple cardiac punctures (2), an indwelling femoral vein catheter in anesthetized animals (3,4), repeated jugular venipuncture (5), or preplaced jugular catheters (6,7). Methods for chronic intravenous catheterization have been described for other species
(8-11).
The procedure reported below combines elements of three previously reported catheterization techniques for small laboratory animals (12), rabbits (13), and cats (14). It was successfully used in our study of the pharmacokinetics of phenobarbital in the cat. This method has also been modified by another researcher for the administration of total parenteral nutrition to cats (15). Our purpose in this report is to provide a detailed description of the catheterization technique. A light surgical plane of anesthesia was required for placement of the catheter. Selection of the anesthetic regimen would be dictated by the resources available and the status of the patient. The neck was clipped and cleansed as for aseptic surgery. A skin incision was made over the jugular vein, and blunt dissection was used to expose approximately 3 cm of the blood vessel. Two 16 cm lengths of 2-0 polyglactin 910 suture (Vicryl, Ethicon, Peterborough, Ontario) were passed under the vein approximately 2 cm apart. The blood vessel was elevated to occlude its lumen both proximally and distally (Figure IA). Using iris scissors and forceps, a small incision was made in the vein through which the catheter was passed. In our experiment, a 16 or 19 gauge, 20.3 cm long Intracath catheter (Deseret Co., Sandy, Utah) with the needle removed was used. Silastic tubing can also be used if preferred. The 19 gauge catheter was used in the smaller cats and the 16 gauge for the remainder. Six to 8 cm of the catheter were gently threaded into the vein so that the catheter tip was at approximately the junction of the caudal and cranial venae cavae. If necessary, the position can be confirmed radiographically as the catheters are radiopaque. The stylet was removed from the catheter and an injection cap (Becton-Dickinson, Rutherford, New Jersey) was placed on the catheter opening. The proximal strand of suture Can Vet J 1989; 30: 432-433
Department of Clinical Studies (Cochrane, Parent, Allen, Valliant), Department of Biomedical Sciences (Black) and Department of Pathology (Lumsden), Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1. This study was funded by the Ontario Veterinary College Pet Trust.
material (i.e. suture closest to the thorax) was tied around the vein and the catheter within (Figure 1B). The distal strand of suture material (i.e. suture closest to the head) was used to ligate the vein and was then passed around the catheter and tied to secure both vein and catheter in place (Figure iB). The skin was closed with 2-0 polypropylene suture (Prolene, Ethicon, Peterborough, Ontario) in a simple interrupted pattern. The catheter was curved and directed caudally on the dorsum of the neck (Figure IC). A
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injection cap -
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Figure 1. Illustration showing placement of jugular catheter: A. Elevation and occlusion of jugular vein. B. Placement of catheter with fixation to the vein. C. Catheter in place prior to bandaging. D. Appearance of cat with bandage in place. (proximal towards thorax; distal = towards head) =
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Using two 2 x 1 cm pieces of adhesive tape, the external portion of the catheter was fastened to the neck at two sites using 2-0 Prolene suture. A sterile gauze square (Nu gauze, Johnson & Johnson, Toronto, Ontario) trimmed to 3 x 3 cm, was covered with a small amount of nitrofurazone ointment (Furazone Soluble Dressing, Langford Inc., Guelph, Ontario) and placed over the surgical site. To maintain the catheter in position, a single piece of adhesive tape was passed around the neck and over both the gauze and the curved exterior portion of the catheter (Figure IC). The entire system was then wrapped with gauze (Kling, Johnson & Johnson, Toronto, Ontario) and bandaging tape (Vetrap, Animal Care Products/3M, St. Paul, Minnesota). The injection cap was left exposed for sampling (Figure 1D).
This simple and effective method is ideally suited for repeat blood sampling in the experimental setting or for the administration of parenteral nutrition to the debilitated patient The bandage was removed every other day and the surgical site cleaned. The residual volume (0.15 mL for the 19 gauge and 0.30 mL for the 16 gauge catheter) was flushed with saline (0.5 mL) between samples if necessary. If the sample interval exceeded 24 hours, dilute heparin solution was used to flush the catheter. Removal of the catheter was accomplished by applying gentle traction to the external portion of the catheter. A light pressure bandage was then applied to the surgical site to prevent bleeding. If the experimental design or chronic patient care require placement of a second indwelling catheter, this can be accomplished without complication by using the other jugular vein. In the experiment for which this technique was designed, a patent catheter was required for eight days. The method proved a successful means of sample collection during this time period. There was no evidence to suggest that the catheter could not have been used for a longer period of time. Complications were minimal. Infection at the surgical site is a potential problem especially with longer periods of catheter usage in a debilitated patient. Tunneling the catheter under the skin to exit at the dorsum of the neck would decrease the opportunity for infection. Care must be taken to avoid inadvertently advancing the catheter into the heart as was done in a few of the earlier experimental cats. Myocardial hemorrhage was present in some of these cats at postmortem examination. The occasional cat was inclined to scratch at the bandage. Clipping of the nails
Can Vet J Volume 30, May 1989
and/or lightly bandaging the hind feet minimized this problem. While this procedure does require general anesthesia and sacrifice of a jugular vein, these features are generally not serious problems, especially in the experimental cat. In summary, we describe a simple and effective method for maintaining chronic intravenous access in the cat. It is ideally suited for repeat blood sampling in the experimental setting or for the administration of parenteral nutrition to the debilitated patient. The technique should be readily adaptable to a variety of species.
Acknowledgments We would like to acknowledge Dr. Walter Ingwersen for his help in designing the procedure.
References 1. Blue J. The blood and blood-forming organs. In: Pratt PW, ed. Feline Medicine. Santa Barbara: American Veterinary Publications Inc., 1983: 149-189. 2. Roye DB, Serrano EE, Hammer RH, Wilder BJ. Plasma kinetics of diphenylhydantoin in dogs and cats. Am J Vet Res 1973; 34: 947-950. 3. Tobin T, Dirdjosudjono S, Baskin SI. Pharmacokinetics and distribution of diphenylhydantoin in kittens. Am J Vet Res 1973; 34: 951-954. 4. Bruni J, Wilder BJ, Perchalski RJ, Hammond EJ, Villarreal HJ. Valproic acid and plasma levels of phenobarbital. Neurology 1980; 30: 94-97. 5. Watson AD. Systemic availability of chloramphenicol from tablets and capsules in cats. J Vet Pharmacol Ther 1980; 3: 45-51. 6. McKieran BC, Koritz GD, David LE, Neff-Davis CA. Pharmacokinetic studies of theophylline in cats. J Vet Pharmacol Ther 1983; 6: 99-104. 7. Baker MA, Burrell E, Penhus J, Hayward JN. Capping and stabilizing intravascular cannulae. J Appl Physiol 1968; 24: 577-579. 8. Hall LL, Delopez OH, Roberts A, Smith F. A procedure for chronic intravenous catheterization in the rabbit. Lab Anim Sci 1974; 24: 79-83. 9. Popovic V, Popovic P. Permanent cannulation of aorta and vena cava in rats and ground squirrels. J Appl Physiol 1960; 15: 727-728. 10. Zatzman ML, South FE. Chronic catheterization and handling procedures for marmots. J Appl Physiol 1971; 31: 309-312. 11. Weirich WE, Will JA, Crumpton CW. A technique for placing chronic indwelling catheters in swine. J Appl Physiol 1970; 28: 117-119. 12. Jacobs P, Adriaenssens L. A simple method for repeated blood sampling in small animals. J Lab Clin Med 1970; 75: 1013-1016. 13. Bazaral M, Hamburger RN. Implantation and stabilization of indwelling vascular catheters in the rabbit. J Appl Physiol 1970; 29: 113-114. 14. Ohnhaus EE, Kosh H, Deyhle P. Intravenous permanent catheterization in cats. Eur J Physiol 1970; 316: 205-207. 15. Lippert AC, Faulkner JE, Evans AT, Mullaney TP. Total parenteral nutrition in clinically normal cats. J Am Vet Med Assoc 1989; 194: 669-676.
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