The phrase “continent of urine” is a misunderstanding of two distinct yet related concepts: “urinary continence” and “continent urinary diversion.” Urinary continence refers to the body’s ability to control the storage and release of urine, preventing involuntary leakage. In contrast, continent urinary diversion is a specialized surgical procedure that creates an internal system for urine storage and controlled emptying. This article explores the mechanisms behind normal bladder control and delves into the specifics of continent urinary diversion.
Understanding Bladder Control
Normal bladder control, or urinary continence, involves a complex coordination between the bladder, sphincter muscles, nerves, and the brain. The bladder, a muscular organ, expands to store urine as it fills from the kidneys. Stretch receptors within the bladder wall send signals to the spinal cord and then to the brain, indicating the bladder’s fullness.
When the bladder fills, the detrusor muscle, which forms the bladder wall, remains relaxed to allow storage. Simultaneously, the internal urethral sphincter, an involuntary muscle at the bladder neck, contracts to keep the urethra closed. The external urethral sphincter, a voluntary muscle located below the internal sphincter, also remains contracted, providing an additional layer of control. When it is appropriate to urinate, the brain sends signals that cause the detrusor muscle to contract and both sphincters to relax, allowing urine to flow out of the body through the urethra. A disruption in any part of this intricate system can lead to urinary incontinence, the involuntary leakage of urine.
Continent Urinary Diversion Explained
Continent urinary diversion is a surgical procedure designed to create an internal reservoir for urine storage when the bladder is no longer functional or has been removed. This procedure allows individuals to control when and how they empty this newly created storage pouch. The primary reasons for this surgery often include bladder cancer, which necessitates removal of the bladder, or severe, irreversible bladder dysfunction caused by conditions like spinal cord injury or birth defects such as spina bifida.
Unlike incontinent diversions, such as an ileal conduit, which continuously drain urine into an external bag, continent diversions offer a significant advantage by maintaining urinary control. The surgical creation of an internal pouch, typically from a segment of the patient’s own intestine, is a key feature. This pouch is designed to hold urine until it is emptied at planned intervals, often through a small opening on the abdomen or, in some cases, through the urethra. The ability to manage urine internally offers a significant improvement in quality of life for many patients.
Methods of Continent Diversion
Several surgical approaches exist for continent urinary diversion, each creating an internal reservoir with a mechanism for controlled emptying.
Indiana Pouch
The Indiana pouch is a common method that uses a section of the ileum (small intestine) and the cecum (part of the large intestine) to form a low-pressure storage reservoir. Continence is achieved by incorporating the ileocecal valve, a natural sphincter, and creating a small opening, or stoma, on the abdominal wall through which a catheter can be inserted to drain urine. Individuals typically empty this pouch by self-catheterization every four to six hours.
Mitrofanoff Procedure
Another technique is the Mitrofanoff procedure, also known as an appendicovesicostomy, which utilizes the appendix to create a narrow channel from the skin surface to the bladder or an intestinal pouch. The appendix’s natural muscular structure helps maintain continence, and a small opening is created, usually in the belly button or lower abdomen, for catheter insertion. This method is often favored for its cosmetic appeal and ease of access for self-catheterization.
Neobladder Construction
A neobladder construction represents a different approach, where a segment of the intestine is reconfigured into a new bladder-like pouch that is then connected directly to the urethra. This allows individuals to void urine through their natural pathway, similar to how they would with an intact bladder, though they may need to use abdominal pressure or perform intermittent self-catheterization if complete emptying is not achieved. The neobladder typically functions by coordinated relaxation of the pelvic floor muscles and straining, rather than relying on bladder wall contractions.
Life with a Continent Diversion
Living with a continent urinary diversion involves adapting to new routines for managing urine output, but it allows for a high degree of independence. Routine care typically includes regular emptying of the internal pouch, often through self-catheterization, every four to six hours throughout the day. Stoma care is also necessary for those with a catheterizable opening, involving cleaning the skin around the stoma and protecting it from irritation. Patients learn specific techniques for inserting and removing the catheter, ensuring proper hygiene to prevent complications.
Individuals with continent diversions may experience common challenges, such as mucus production from the intestinal lining of the pouch, which requires periodic irrigation to prevent blockages. Urinary tract infections can also occur, necessitating prompt medical attention. Stone formation within the pouch is another potential complication, sometimes requiring intervention. Regular follow-up appointments with healthcare providers, including urologists and specialized nurses, are important to monitor the diversion’s function, address any issues, and ensure long-term health. With consistent care and adherence to medical advice, many individuals with a continent urinary diversion lead full, active lives, participating in a wide range of daily activities and sports.