Dysfunctional Elimination Syndrome
Urination is a complex function and often misunderstood. It involves the coordination of two completely different muscle systems. The bladder is a smooth muscle and stores urine (up to several ounces depending on the age of the child) and the sphincter muscle (which we can control) keeps the urine from leaking out.
Once the bladder is full, it signals the brain to be emptied. The sphincter muscle must then relax, and the bladder muscle contracts so urine can flow.
Introduction to Dysfunctional Elimination Syndrome
Few things are more distressing to a family than having a child who is continuously wet. It can become increasingly difficult for a child to hold back such a powerful bladder. He or she may wet themselves despite their best efforts to hold it back, or they may be doubled over with lower abdominal cramps arising from the bladder. Families can find comfort in knowing that it's a common problem that children generally outgrow.
Many children wet themselves because they've acquired an abnormal pattern of urination in which the various parts of the urinary tract are not working together. That pattern can be changed into a normal one with a proper training program.
Patterns of Abnormal Voiding
Some children hold the urine for extensive periods and overstretch their bladders. When they finally do urinate, it's with perfectly normal coordination. Other children have difficulty relaxing the sphincter during urination and void against it, straining the bladder muscle extensively in the process.
These abnormal voiding patterns may also be associated with constipation. Collectively, they're referred to as dysfunctional elimination syndrome (DES).
Infection occurs commonly with voiding dysfunction. The normal bladder is remarkably resistant to infection because of its ability to wash out and eliminate bacteria with every urination. If urine is held too long or is incompletely discharged, bacteria may increase.
The high pressure generated by muscles straining against themselves may break down the one-way mechanism of urine flow which normally prevents urine from going back up into the kidneys from the bladder. It may also impede the flow of urine from the kidneys into the bladder.
Urination occurs when we release the bladder by relaxing the sphincter. The cooperation between bladder and sphincter is carefully coordinated by the nervous system through a reflex arc centered in the base of the brain.
Abnormal Voiding and Voiding Dysfunction
Individuals cannot willfully contract the bladder muscle like they can the sphincter muscle. As children mature, they desire to control their bladders and not wet themselves. They learn to do this early in life by overriding the normal tendency of the sphincter to relax; they forcibly contract their sphincter instead and prevent urine from escaping.
This forced contraction to hold urine back is a normal reaction and not particularly harmful. But if the child continues to maintain a contracted sphincter against a straining bladder, an unhealthy situation can develop as the two muscles strain against one another. Over time, the bladder wall may reach two to three times its normal thickness due to enlargement of the muscle fibers.
Voiding dysfunction appears to be an acquired disorder, and the cause isn't always clear. Because proper voiding requires relaxation above all else, it's understandable that a busy child, anxious to get back to play, may not take the proper time to urinate.
Because voiding dysfunction is essentially a lack of coordination between the bladder and sphincter, the key to treatment centers on a voiding retraining program. The normal reflex that coordinates bladder and sphincter is so strongly ingrained in the nervous system that all that is required is to stop the voluntary overriding of the sphincter. With proper attention to a bladder retraining program, the abnormal pattern of voiding can be broken and the normal pattern restored.
Bladder retraining is based on the principle of taking all the pressure off the bladder to allow its strained muscles to recover. To do this, two important principles are incorporated into the bladder retraining program:
- Frequent voiding
- Complete voiding
The time of voiding should be determined in advance and one should rigidly adhere to the schedule. Generally, a voiding schedule of every two hours during the day is selected and marked on a voiding calendar or diary. See an (PDF).
This voiding routine is only effective if the bladder is emptied completely without interruption. If contraction of the sphincter occurs during voiding, interrupting the stream and the bladder contraction, the bladder contraction may be lost. Adhering to a strict schedule will keep the pressure in the bladder down to a level where the muscles will recover and normal function is restored.
UVA's Voiding Dysfunction Clinic offers services to help children and adolescents who have problems with bowel and bladder function. Learn how to change your child's voiding functions and make an appointment with our Pediatric Urology clinic.