An external catheter is a non-invasive urine collection system used to manage urinary incontinence. Unlike indwelling catheters, which are inserted into the urethra to reach the bladder, this device adheres to the external genitalia to collect urine as it leaves the body naturally and diverts it into a separate receptacle. This design significantly reduces the risks associated with internal devices, particularly catheter-associated urinary tract infections (CAUTIs).
How External Catheters Work
The mechanism of an external catheter relies on a passive collection system that harnesses gravity to manage fluid flow. The system consists of three fundamental parts that divert urine away from the skin. First, a collection device, such as a soft sheath or flexible pad, adheres to the genitalia to capture the voided urine. This component creates a secure, leak-proof seal without causing discomfort or restricting blood flow.
A small port on the collection device connects to a length of flexible connection tubing, which channels the fluid in a continuous downward path, preventing backflow toward the body. The final component is the drainage bag or collection unit, which stores the urine. This bag is typically secured to the patient’s leg for mobility or positioned at the bedside, ensuring it remains below the level of the bladder for gravity-assisted drainage.
Medical Reasons for Use
External catheters are a preferred management strategy for patients experiencing urinary incontinence who do not have urinary retention or a blockage preventing bladder emptying. They are often recommended for individuals with mobility challenges or cognitive impairment that makes reaching a toilet difficult or impossible. This includes patients with conditions such as dementia, spinal cord injury, or limited movement.
For people who use absorbent products like pads or briefs, external catheters prevent incontinence-associated dermatitis (IAD) and skin breakdown. By immediately diverting urine away from the skin, the device minimizes prolonged exposure to moisture and irritants. Healthcare guidelines support the use of external catheters in male patients as a safer alternative to indwelling catheters, reducing the risk of infection. They are also used in non-critical care settings for short-term monitoring of urine output or following surgical procedures where internal catheter use carries a higher risk of complications.
Anatomical Variations in Design
The design of external catheters is specialized to accommodate the distinct anatomies of male and female users. The male external catheter is commonly known as a condom catheter or urinary sheath due to its resemblance to a condom. This device is a flexible sheath that rolls over the penile shaft, using an adhesive lining or a separate adhesive strip to remain securely in place.
The materials used are typically soft silicone or, less frequently, latex, with silicone often preferred for its breathability and hypoallergenic properties. For female anatomy, external catheters present a greater design challenge, often involving a flexible cup, pouch, or wicking material placed over the external urethral opening. Newer female designs may incorporate a low-pressure suction system to actively draw urine away from the perineal area and into the collection container. These devices are intended to reduce skin contamination and prevent complications arising from traditional absorbent products.
Application and Skin Health Management
Proper application of an external catheter begins with skin preparation to ensure a secure seal and maintain skin integrity. The genital area must be thoroughly cleaned with mild soap and water and fully dried before application. For male users, selecting the correct sheath size based on penile circumference is fundamental to prevent leakage from an ill-fitting device or tissue damage from one that is too tight.
A skin barrier product may be applied before the adhesive sheath to protect the tissue from irritation and enhance the catheter’s adherence. The device should be secured snugly but without excessive tension to prevent pressure injuries. Regular inspection of the skin, often made possible by translucent silicone materials, is necessary to check for any signs of redness, swelling, or breakdown.
External catheters, particularly the male sheath type, should be changed daily, or at least every 48 hours, to maintain hygiene and allow for a complete skin assessment. The drainage bag must be emptied frequently and positioned lower than the bladder to prevent the backflow of urine, which can lead to skin irritation or infection. Maintaining a consistent hygiene routine and ensuring the catheter is securely taped or strapped without pulling on the skin minimizes the risk of complications and maximizes comfort.