“Foley” Catheter Articles


  • Complications of Foley catheters--is infection the greatest risk? - Abstract

    PURPOSE:Foley catheters cause a variety of harms, including infection, pain and trauma. Although symptomatic urinary tract infection and asymptomatic bacteriuria are frequently discussed, genitourinary trauma receives comparatively little attention.

    MATERIALS AND METHODS:A dedicated Foley catheter nurse prospectively reviewed the medical records of inpatients with a Foley catheter at the Minneapolis Veterans Affairs Medical Center from August 21, 2008 to December 31, 2009. Daily surveillance included Foley catheter related bacteriuria and trauma. Data were analyzed as the number of event days per 100 Foley catheter days.

    RESULTS:During 6,513 surveyed Foley catheter days, urinalysis/urine culture was done on 407 (6.3%) days. This testing identified 116 possible urinary tract infection episodes (1.8% of Foley catheter days), of which only 21 (18%) involved clinical manifestations. However, the remaining 95 asymptomatic bacteriuria episodes accounted for 39 (70%) of 56 antimicrobial treated possible urinary tract infection episodes (for proportion of treated episodes with vs without symptomatic urinary tract infection manifestations, p = 0.005). Concurrently 100 instances of catheter associated genitourinary trauma (1.5% of Foley catheter days) were recorded, of which 32 (32%) led to interventions such as prolonged catheterization or cystoscopy. Trauma prompting an intervention accounted for as great a proportion of Foley catheter days (0.5%) as did symptomatic urinary tract infection (0.3%) (p = 0.17).

    CONCLUSIONS: In this prospective surveillance project, intervention triggering Foley catheter related genitourinary trauma was as common as symptomatic urinary tract infection. Moreover, despite recent increased attention to the distinction between asymptomatic bacteriuria and symptomatic urinary tract infection in catheterized patients, asymptomatic bacteriuria accounted for significantly more antimicrobial treatment than did symptomatic urinary tract infection. Elimination of unnecessary Foley catheter use could prevent symptomatic urinary tract infection, unnecessary antimicrobial therapy for asymptomatic bacteriuria and Foley catheter related trauma.

    Written by:
    Leuck AM, Wright D, Ellingson L, Kraemer L, Kuskowski MA, Johnson JR. Are you the author?
    VA Medical Center, University of Minnesota, Minneapolis, Minnesota, USA.

    Reference: J Urol. 2012 May;187(5):1662-6. doi: 10.1016/j.juro.2011.12.113.



    Published January 15, 2013
  • Indwelling Catheter Definition & Types

    What is an Indwelling Catheter?

    Indwelling Catheter Illustration

    An indwelling urinary catheter (IUC), generally referred to as a “Foley” catheter, is a closed sterile system with a catheter and retention balloon that is inserted either through the urethra or suprapubically to allow for bladder drainage. External collecting devices (e.g. drainage tubing and bag) are connected to the catheter for urine collection 

    Indwelling urinary catheters are recommended only for short-term use, defined as less than 30 days (EAUN recommends no longer than 14 days.) The catheter is inserted for continuous drainage of the bladder for two common bladder dysfunction: urinary incontinence (UI) and urinary retention.

    Written by: Diane K. Newman, DNP, ANP-BC, FAAN
    Published April 28, 2019
  • Indwelling Catheters

    Urologic Catheters: Indwelling | Intermittent | External


    Indwelling Catheters


    An indwelling urinary catheter, generally referred to as a “Foley” catheter, is a closed-sterile system with a catheter and retention balloon that is inserted either through the urethra or suprapubically to allow for bladder drainage. Indwelling urethral catheters are used to relieve urinary retention and to manage long-term urinary incontinence (UI).


    Indwelling urinary catheters are recommended for short-term use and include management of acute urinary retention, postoperative bladder decompression, and monitoring urinary output in acutely ill patients. Catheter-associated urinary tract infection (CAUTI) is the most common type of infection acquired in the health-care setting. Indwelling catheters are associated with multiple complications.


    This area provides clinical research evidence from publications with best practices for clinical care experts. The resources are consistent with the UroToday commitment of accurate, relevant, and reliable content.


    The content in this area, along with the clinical evidence and publications, is designed to support clinical practioners with an intergrated clinical approach to patient care. The tools are from leadng experts and are designed for clinical practioners for use with their patients.

    New from APIC 2013

    jarvis silveralloy

    Nurse-driven IUC Removal Algorithm

    iuc algorithm

    Indwelling Urinary Catheter

    iuc newman

    Published January 1, 2013
  • Indwelling Urinary Catheters: Types

    Indwelling urinary catheters (IUCs) are semi-rigid, flexible tubes. They drain the bladder but block the urethra. IUCshave double lumens, or separate channels, running down it lengthwise. One of the lumen is open at both ends and allows for urine drainage by connection to a drainage bag.


    The other lumen has a valve on the outside end and connects to a balloon at the tip; the balloon is inflated with sterile water when it lies inside the bladder, and allows for retention in the bladder.  These are known as two-way catheters.  

    The name of the Foley catheter comes from the designer, Frederic Foley, a surgeon working in Boston, Massachusetts, in the 1930s. His original design was adopted by C. R. Bard, Inc. who manufactured the first prototypes and named them in honor of the surgeon.

    Foley Catheter Sizes

    Foley Catheter sizes chart
    Catheter sizes are colored-coded at the balloon inflation site for easy identification

    The relative size of a Foley catheter is described using French units (Fr).  In general, urinary catheters range in size from 8Fr to 36Fr in diameter. 1 Fr is equivalent to 0.33 mm = .013" = 1/77" in diameter.  

    The crosssectional diameter of a urinary catheter is equal to three times the diameter.

    Since urethral mucosa contains elastic tissue which will close around the catheter once inserted, the catheter chosen should be the smallest catheter that will adequately drain urine.  

    Size Considerations

    • The routine use of large-size catheters diameters can cause more erosion of the bladder neck and urethral mucosa, can cause stricture formation, and do not allow adequate drainage of peri-urethral gland secretions, causing a buildup of secretions that may lead to irritation and infection. 
    • Larger Fr sizes (e.g., 20-24 Fr) are most commonly used for drainage of blood clots.  
    • The most commonly utilized indwelling transurethral and suprapubic catheters range from 14 to 16Fr in both adult females and males. 
    • A 14 or 16 Fr is also the standard catheter in most commercially available IUC insertion kits or trays.
    • In adolescents, catheter size 14 Fr is often used but for younger children, pediatric catheter sizes of 6-12 Fr are preferred.  

    Shape and Design Variations

    Foley Catheter
    The distal end of most urinary catheters contains two ports (lumen or channel or dual lumen).  One is a funnel shaped drainage channel to allow efflux of urine once the catheter is placed and the other is the inflation/deflation channel for infusion of water into the retention balloon.  The infusion port for the balloon is usually labeled with the size of the balloon (5cc or 30 cc) and the size of the catheter.

    3 Way Indwelling Catheter 
    Three-way catheters are available with a third channel to facilitate continuous bladder irrigation or for instillation of medication.  This catheter is primarily used following urological surgery or in case of bleeding from a bladder or prostate tumor and the bladder may need continuous or intermittent irrigation to clear blood clots or debris. 

    Drainage Eyes
    The catheter should have a smooth surface with two drainage eyes at the tip that allow for urine drainage.

    Drainage eyes are placed either laterally or opposed. Opposing drainage eyes generally facilitate better drainage.

    Catheter products have changed significantly in their composition, texture, and durability since the 1990s.

    The challenge is to produce a catheter that matches as closely as possible to the normal physiological and mechanical characteristics of the voiding system, specifically the urethra and bladder. Foley catheters come in several subtypes, which are described in the area designs


    1. Jahn P, Beutner K, Langer G. Types of indwelling urinary catheters for long-term bladder drainage in adults. Cochrane Database of Systematic Reviews 2012, Issue 10. Art. No.: CD004997. DOI: 10.1002/14651858.CD004997.pub3.Newman DK, Cumbee RP, Rovner ES. Indwelling (transurethral and suprapubic) catheters. In: Newman DK, Rovner ES, Wein AJ, editors. Clinical Application of Urologic Catheters and Products.  Switzerland: Springer International Publishing;2018,  47-77.
    2. Newman DK. Devices, products, catheters, and catheter-associated urinary tract infections. In: Newman DK, Wyman JF, Welch VW, editors. Core Curriculum for Urologic Nursing. 1st ed. Pitman (NJ): Society of Urologic Nurses and Associates, Inc; 2017, 439-66.
    3. Newman DK. The indwelling urinary catheter: Principles for best practice. JWOCN. 2007;34:655-61 DOI: 10.1097/01.WON.0000299816.82983.4a
    4. Newman DK, & Wein AJ. Managing and Treating Urinary Incontinence, Second Edition.  Baltimore: Health Professions Press;2009a;445-458.

    Written by: Diane K. Newman, DNP, ANP-BC, FAAN
    Published April 28, 2019
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