Bowel changes after injuries
After some injuries, the bowel will no longer work like it did before. Here we review how it functions and changes in how to complete this process that may be necessary.
The digestive system includes the mouth, stomach, esophagus, intestines, rectum, and anus. When food or beverages are consumed, they travel through this system until they are eliminated in the form of stool or a bowel movement (B.M.). Messages are sent from the brain through the spinal cord and sacral nerves. The message tells the body that it is time to empty the bowel.
Normal bowel function
- When the bowel is full of stool, it stretches and pushes on the area nerves. Note that it is important to eat enough fiber, so the stool has enough bulk to stretch the bowel.
- The nerves send a sensory message from the bowel, through the sacral nerves, and up through the spinal cord. When this sensory message reaches the spinal cord, part of it begins to loop around in the cord, setting off a reflex, which causes the bowel to squeeze. The other part of the message travels up to the brain.
- When the message reaches the brain, the urge to have a B.M. is felt.
- When the person decides it is the right time to have a B.M., the message is sent back down the cord, through the sacral nerves, all the way to the sphincter muscle (near the anus). The message tells the muscle to open up and let the stool out. If it is not a good time, the message would then tell the muscle to stay closed until there is a better time to empty.
Bowel function after spinal cord injury
After a spinal cord injury, the bowel keeps working, but the brain may have trouble understanding the messages from the bowel and spinal cord. This may cause bowel accidents, or incontinence, and/or constipation. These may become ongoing issues.
Reflex bowel
If the injury is located at T12 or higher, the bowel will empty by a reflex. When the bowel empties by a reflex, it is called a reflex bowel. This means that when the rectal vault is full of stool, it will increase the pressure and then stool will be pushed out. The key to continence is to empty the rectal vault before it becomes too full and pushes stool out at an unacceptable time.
- The rectum gets full of stool, stretches and pushes on area nerves.
- A message is sent from the bowel to the sacral nerves and then to the cord.
- When the message reaches the cord, it loops around in the cord, setting off a reflex.
- The reflex tells the sphincter muscle, near the anus, to open and let the stool out of the body.
Because the cord is injured, the rest of the message does not reach the brain. The message stays in the cord. This is different because now the brain does not send a message down the cord to tell it whether or not it is a good time to empty the bowel. The reflex allows the muscle to open when it feels full.
The bowel program for a reflex bowel is a digital stimulation and/or a suppository, depending on a person’s level of feeling near his/her anus and rectum.
Non-reflex bowel
If the injury is at L1 or below, it will not cause a reflex to happen. This type of bowel is called the non-reflex bowel.
- The rectum fills with stool, stretches and pushes on area nerves.
- A signal is sent from the bowel to the sacral nerves where it then tries to reach the cord.
- The signal never reaches the cord because the cord ends at around L1 or L2. When the injury is below where the cord ends, the signals are not able to travel inside the cord.
- Because the signal is not able to reach the cord, no reflex happens, and the bowel does not squeeze. The sphincter muscle remains loose, so if too much stool collects in the rectum, it will come out.
This is different from the reflex bowel because the signal cannot reach the cord to cause the reflex. It also cannot reach the brain. This means that the brain cannot tell the body when it is a good time to have a bowel movement. Without the reflex, the bowel empties whenever the rectal vault becomes too full to contain the contents.
The bowel program for a non-reflex bowel is a manual evacuation, with or without a suppository.
Toileting program
Medical aids
The doctor may prescribe medicine to help have bowel movements. The medicines may soften stool (Colace, Peri-Colace, etc.) and/or add bulk (Metamucil, Fibercon, etc.) to it. They may be taken once or twice a day. You may need a suppository if constipation is a problem. These medicines may be taken once a day or less often when needed. Take them as scheduled unless you are having diarrhea. If diarrhea occurs, stop taking the medicines and call the doctor during business hours.
Keeping a schedule
Stay on a schedule. Having a timed bowel program is useful during retraining. Try to schedule this around 30 minutes after meals. Provide proper supervision during the bowel program in order to prevent falls or other injuries that may occur if unattended.
If bowel accidents are a problem, start keeping a record of when all bowel movements occur. You may notice that bowel accidents happen in the morning but not during the scheduled time. Keeping track of this is helpful when planning the best time for making the program schedule. Once a time has been set and is successful, stay on schedule. This should help decrease bowel accidents.
If bowel control has not returned, the person may need to wear adult briefs (adult diapers) in order to prevent accidents. The brief needs to be changed at least daily and with each bowel accident.
The bowel program worksheet can help patients organize and review their bowel program.