Urinary catheters are indispensable for the treatment of urinary obstructions as well as diagnostic procedures and perioperative care. However, risks associated with their use include catheter-associated urinary tract infections, urethral trauma, biofilm formation, and encrustation. Effective catheter management depends on strict adherence to evidence-based protocols that select species-appropriate catheter materials, use aseptic insertion techniques, and prioritize timely removal. Proper catheter size and securement are critical to prevent recurrence of urethral obstruction and iatrogenic injury in feline patients. Complications associated with indwelling catheters (e.g., bacteriuria) highlight the challenges of biofilm resistance and limited efficacy of routine catheter changes. Prophylactic measures, including sterile maintenance, antimicrobial-coated catheters, and vigilant monitoring for leakage or discomfort, are essential to mitigate further complications. Maintenance of an indwelling urinary catheter is paramount and includes aseptic cleaning of the catheter entry site, a sterile closed collection system below the bladder level, and frequent inspection for signs of inflammation or leakage to prevent ascending infections and other complications.<\/p>\n
Take-Home Points<\/strong><\/p>\n <\/div><\/div><\/p>\n The earliest documented use of a urinary catheter traces back to the 6th century BC in the Sushruta Samhita<\/em>, a foundational Sanskrit medical text by the Indian surgeon Sushruta.1<\/sup> Modern catheterization evolved significantly in 1929 when Frederic Foley introduced a self-retaining \u201chemostatic bag catheter,\u201d later refined in 1937 in his publication in Journal of Urology<\/em>.2,3<\/sup><\/p>\n Although global veterinary catheter usage data are not systematically reported, industry estimates suggest tens of millions of units are used annually. This high usage reflects the prevalence of urinary disorders among companion animals. Approximately 50% of cats over age 10 develop chronic lower urinary tract diseases that necessitate catheterization.4<\/sup> Urolithiasis, a common cause of urethral obstruction, accounts for 10% to 23% of lower urinary tract signs and often requires repeated interventions.5<\/sup> Dogs increasingly undergo catheterization for urinary incontinence and postoperative urinary retention management.6<\/sup><\/p>\n Although urinary catheters remain indispensable for bladder drainage, their use carries risks such as catheter-associated urinary tract infections (CAUTIs), urethral trauma, and mineral encrustation.7,8<\/sup> Effective mitigation of these complications requires meticulous attention to indications for catheterization, aseptic insertion techniques, appropriate maintenance protocols, and timely removal. Optimal catheter management is critical to minimize adverse outcomes.<\/p>\n This review examines current catheterization practices in veterinary medicine, including evidence-based indications, catheter selection criteria, insertion and removal methodologies, and daily maintenance strategies. Additionally, it explores common complications such as CAUTIs, trauma, and biofilm formation alongside preventive measures to enhance patient safety and clinical outcomes.<\/p>\n Urinary catheterization is indicated for relieving urethral obstructions<\/a>, evacuating the urinary bladder, obtaining sterile urine samples, and facilitating diagnostic or surgical procedures (e.g., neurogenic lower urinary tract dysfunction, urogenital surgery). Critically ill patients with prolonged immobilization also warrant urinary catheterization. Current guidelines emphasize prompt catheter removal once clinical objectives are met as prolonged catheter use increases risks for complications.9,10<\/sup> Postoperative catheters should be discontinued unless specific medical needs warrant continuation.11<\/sup><\/p>\n Ideal catheter materials minimize urethral inflammation, resist mechanical deformation (i.e., kinking), and inhibit bacterial colonization. Common options include silicone, Teflon-coated latex, and polymer-coated variants. Silicone catheters, though stiffer, demonstrate superior resistance to kinking and reduced urethral irritation in humans when compared to latex.12,13<\/sup> Polypropylene catheters, although easy to insert, are associated with significant urethral and bladder trauma in cats and are generally discouraged.14<\/sup> General-use catheters (e.g., red rubber, feeding tubes) are used for intermittent and short-term indwelling catheterization and exhibit higher bacterial adherence. Unlike balloon-retained Foley catheters, general-use catheters require external securement such as a finger-trap pattern to the prepuce, suturing to the vulvar labia, or perineal taping with a tail wrap for females. Antimicrobial- or hydrophilic-coated catheters may reduce infection risks, yet evidence remains limited within veterinary medicine.10<\/sup><\/p>\n Urinary catheter size is measured on the French (Fr) scale, where 1 Fr corresponds to an external diameter of 0.33 mm. The smallest diameter that allows for adequate urine flow should be selected. For male cats, nonballoon tomcat catheters (3.5 Fr through 5 Fr) should be sutured for stabilization. Recommended sizes are 3.5 Fr though 5 Fr for cats and small dogs (e.g., Chihuahua, toy poodle), 5 Fr through 8 Fr for medium-sized dogs (e.g., beagle, bulldog), 8 Fr through 10 Fr for large dogs (e.g., Labrador retriever, Rottweiler), and 10 F through 14 Fr for giant-breed dogs (e.g., Mastiff, Great Dane)10<\/sup> Balloon sizes typically range from 3 mL through 10 mL for cats and dogs. Sterile saline or water is recommended for inflation to prevent crystallization or rupture of the catheter balloon.15<\/sup> Common urinary catheter types selected for intermittent procedures among dogs and cats (e.g., sterile sample collection, bladder drainage) are illustrated in FIGURE 1<\/strong>.<\/p>\n\n
Indications for Catheterization of Companion Animals<\/h2>\n
Catheter Selection<\/h2>\n
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2025\/12\/Rasool_FoleyCatheter_TVPOnline_Fig1A-1024x683.png\")
FIGURE 1A. Types of urinary catheters used for obstruction management in cat and dog- Two-way silicon Foley catheter. Courtesy Kruuse.<\/span><\/a><\/div><\/div>
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2025\/12\/Rasool_FoleyCatheter_TVPOnline_Fig1B.png\")
![\"\"](\"https:\/\/navc.sitepreview.app\/todaysveterinarypractice.com\/wp-content\/uploads\/sites\/4\/2025\/12\/Rasool_FoleyCatheter_TVPOnline_Fig1C.png\")