The digestive tract as a whole is a hollow tube extending from the mouth to the anus. The bowel, the final portion of the tract, is where waste products of digested food are stored until they are emptied from the body in the form of stool, or feces.
A bowel movement happens when the rectum (the last segment of the bowel) becomes full and the muscle around the anus (the anal sphincter) opens.
Paralysis often damages the nerves that control the bowel. If the injury is above the T-12 level, the ability to sense a full rectum may be lost. The anal sphincter remains tight, however, so bowel movements will occur on a reflex basis. This means that when the rectum is full, the defecation reflex will occur. This is called an upper motor neuron or reflex bowel. It is managed by triggering the defecation reflex at socially appropriate times and places.
A spinal cord injury below T-12 may damage the defecation reflex and relax the anal sphincter muscle. This is known as a lower motor neuron or flaccid bowel. Management of this type of bowel may require more frequent attempts to empty the bowel and manual removal of stool.
Not being able to control the sphincter can result in an inability to have a bowel movement. This can cause your stool to be impacted and the solid waste to be retained. Impaction can be serious if it occurs high up in the bowel.
The best way to prevent bowel accidents is to follow a schedule. You want to teach your bowels when to have a movement.
Methods for emptying the bowel
Each person's bowel program should be individualized, taking into account the diagnosis or nerve damage, as well as other factors.
Most people perform their bowel program at a time of day that fits in with their prior bowel habits and current lifestyle. The program usually begins with insertion of either a suppository or a mini-enema, followed by a waiting period of approximately 15-20 minutes to allow the stimulant to work. Preferably, this part of the program should be done on the commode.
After the waiting period, digital stimulation is done every 10-15 minutes until the rectum is empty. Those with a flaccid bowel frequently omit the suppository or mini-enema and start their bowel programs with digital stimulation or manual removal. Bowel programs typically require 30-60 minutes to complete.
Some bowel factoids:
- It is not necessary for good health to have a bowel movement every day.
- Bowels move more readily after a meal.
- Fluid intake of two quarts (or two quarts per day) aids in maintaining a soft stool; warm liquid before trying will also aid bowel movement.
- Follow a healthy diet including fiber in the form of bran cereals, vegetables and fruits. Bran is one of the cheapest and most easily available forms of natural laxatives.
- Activity and exercise promote good bowel health.
Spinal Cord Injury Information Center, University of Washington School of Medicine, Rehabilitation Medicine Department