Dysfunctional Elimination Syndrome
Urination is a complex function and often misunderstood. It involves the coordination of two completely different muscle systems. The bladder is smooth muscle ...
Urination is a complex function and often misunderstood. It involves the coordination of two completely different muscle systems. The bladder is 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.
Few things are more distressing to a family than having a child who is continuously wet. The child suffers the ridicule of his classmates, the odors are offensive, the laundry mounts and the child agonizes over his helplessness in bringing the end to the seemingly intractable problem. It becomes increasingly difficult for the child to hold back such a powerful bladder and he may be seen, at times, doubled over with lower abdominal cramps arising from the bladder or wetting himself despite his best efforts to hold it back. If the family can take any comfort from any of this, perhaps it comes from the realization that the problem is common and that children generally outgrow it. In the meantime, however, the agony continues and there exists a small subgroup of these children who actually damage their urinary tract in the process. These are legitimate reasons to want to get to the bottom of this problem quickly and bring it under control.
Although there are some children who are wet from purely anatomical causes, the bulk of those afflicted are wet because they have acquired an abnormal pattern of urination in which the various parts of the urinary tract are not working together in a coordinated manner. Fortunately, that pattern can be changed into a normal one with a proper training program.
The purpose of this primer is to enlighten the family as to the mechanisms of normal and abnormal voiding so that they can take part in the training program in an informed way. Once the reason for the problem is recognized, the battle is half won.
Patterns of Abnormal Voiding
The pattern of abnormal voiding behavior seen in children can be quite variable. Some children hold the urine for extensive periods, overstretching their bladders, yet when they finally do urinate, they urinate with perfectly normal coordination. Other children have difficulty relaxing the sphincter during urination and void against the sphincter, straining the bladder muscle extensively in the process. The outcome is inefficient voiding. All of these abnormal voiding patterns may also be associated with constipation. These patterns collectively are referred to as dysfunctional elimination syndrome (DES).
Infection occurs commonly with voiding dysfunction. The normal bladder is remarkably resistant to infection under ordinary circumstances because of its ability to wash out and thus eliminate bacteria with every urination. If, however, 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 then, not because we voluntarily contract the bladder, but rather because we release the bladder, while it is under tension, by relaxing the sphincter. So fundamental to urination is the cooperation between bladder and sphincter that the activity is carefully coordinated by the nervous system through a reflex arc centered in the base of the brain. Newborn infants do it automatically. What then goes wrong in children with voiding dysfunction?
Abnormal Voiding and Voiding Dysfunction
Although an individual cannot willfully contract his bladder muscle, he can willfully contract his sphincter muscle. In some respects, it is simple to stop urination than it is to start it. As infants grow into children and become more aware of their bladders they are overcome with the desire to control their bladders and not wet themselves every time the bladder reflex is ready to kick off. They learn to do this very early in life by overriding the normal tendency of the sphincter to relax; they forcibly contract their sphincter instead, thus preventing any urine from escaping.
This forced contraction of the sphincter to hold urine back is a normal reaction of children to prevent wetting and is not particularly harmful provided that the child uses those few moments to get to the bathroom where he can relax the sphincter and let the urine escape.
If, however, the child continues to maintain his sphincter contracted against a straining bladder, an unhealthy situation develops in which the two muscles strain against one another. Over time, the bladder wall may reach two to three times its normal thickness because of enlargement of its muscle fibers which now stand out like the muscles of weight lifters.
Although voiding dysfunction appears to be an acquired disorder (i.e., they are not born with it), the cause is not always clear. In general, these children tend to be bright, busy, even hyperactive at times. Because proper voiding requires relaxation above all else, it is understandable that a busy child, anxious to get back to play, may not take the time to perform the act of urination as conscientiously as he should. Furthermore, any social or family pressures may interfere with proper relaxation.
In most instances, voiding dysfunction can be diagnosed by the characteristic history of holding the urine back until the last minute, voiding explosively or intermittently, or involuntary wetting. The history often begins around the time of potty training as a child first begins to exert voluntary control over urination.
Voiding Cystourethrogram VCUG
A VCUG study is a special x-ray of the bladder and urethra. The studies are performed in the Radiology Department (1st floor, Hospital East- the big white building). Sedation may be administered depending on the age of the child, following which a catheter or small tube is placed into the bladder. Contract dye/fluid is then instilled into the bladder through the catheter and x-rays are taken. At the end of the study the catheter is removed and additional images are obtained.
Because voiding dysfunction is basically a lack of coordination between the bladder and sphincter, the key to treatment centers on a voiding retraining program. Fortunately, the normal reflex which 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 and allow the system to go back to its normal function. However, this may not be easy. The pattern of tightening the sphincter may, by now, be well established in the child and the thickened bladder muscles may be particularly difficult to hold back. Nonetheless, 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 2 hours during the day is selected and marked on a voiding calendar or diary. See an example diary (PDF). The child should then be sent to the bathroom at the appointed time without regard to his perception of whether or not he needs to void.
This voiding routine is effective, however, only if the bladder is emptied completely. The stretched smooth muscle of the bladder will empty the bladder completely if released and allowed to do so without interruption. But if contraction of the sphincter occurs during voiding, interrupting the stream and the bladder contraction, the bladder contraction may be lost. The bladder, though still not empty, may not be under the tension it was at the beginning of urination and thus possibly may not be started again. The child is likely to announce that he has finished and is ready to go out and play again, even though his bladder is still half full.
In general, if a child voids every 2 hours and empties his bladder completely, he will keep the pressure in his bladder down to a level where the muscles will recover and normal function will be restored.
The expenditure of time and energy to normalize voiding in these children can be exhausting to the parents and child alike, and there is a decided tendency to quit these training sessions in favor of simpler or less time consuming approaches. The parents will often tell the child to do this himself or else rely on medication to correct the problem. The result of such short cuts is inevitably failure.
There is no substitute for the discipline required in voiding by the clock, concentrating on a continuous stream at every void, and maintaining careful records in a voiding diary. Progress can be slow at times, but only with proper dedication to the effort can success be achieved.