Have you ever thought about the fact that your GI tract moves? This is particularly important when thinking about childhood feeding disorders, especially considering how many GI related diseases and associated symptoms can cause a disruption in the GI tract’s continuous and vital movement.
Gastrointestinal (GI) motility is defined as the coordinated contractions and relaxations of the muscles of the GI tract necessary to move contents from the mouth to the anus. In order for proper movement to occur through the GI tract, it takes a combination of reactions from local reflexes in the GI tract (peristalsis), contraction and relaxation of intestinal muscles, and stimulation from neurons within the GI tract. It takes a lot of work on the part of your brain and your GI tract to make sure that food and liquid are able to enter your mouth, go down your throat and esophagus, through your stomach, small intestines and large intestines and exit your body without slowing down, stopping or hurting.
There are many GI related diseases and associated symptoms that can negatively affect GI motility. The most common disorders associated with disruption in the movement of the GI tract that we see on the Feeding Team are GERD (Gastroesophageal Reflux Disease) and Constipation. Though we treat these two disorders most frequently, we also recognize that our children with underlying genetic disorders, chromosomal abnormalities, cerebral palsy, type 1 diabetes mellitus, previous abdominal surgery, Down’s Syndrome and several other chronic conditions have further impairment of their GI motility. We also very commonly hear that patients had some type of viral illness that preceded their trouble with “movement” in their GI tract.
Symptoms that these children present with include nausea, vomiting, feeling full quickly, refusing to eat, pain just beneath the sternum and weight loss. This can look different depending on the age and specific eating challenge among patients. For example, an infant who has impaired GI motility may eat very small volumes frequently and vomit if more liquid than they readily accept is forced on them. An older toddler may prefer to graze throughout the day and never take more than a couple bites of anything offered at one time, also having a highly likelihood of vomiting if further eating is expected. A preschooler may exhibit the same type of limitation of liquids and foods, but also may only feel the need to stool during meals. This is in response to a normal part of digestion, the “gastrocolic reflex” (the body’s way of recognizing the need for more room for more food by stimulating the GI tract to move things along and out through the anus). This reflex works very well in a normally functioning GI tract with potty training when you have the child sit on the toilet for 5 minutes after each meal. However, if the child has impairment of their GI motility and they have learned to hold their stool otherwise, this reflex can cause pain and frustration if the child is only stooling while eating with associated pain.
In our children who are wheelchair bound and/or who have dependency upon gastrostomy tubes, impaired gastric motility can look a lot like reflux. In fact, I often explain GI dysmotility as being more of the mechanistic part of reflux – food and liquid just do not go in the right direction! These patients have frequent vomiting, inability to tolerate bolus feeds or even slowly administered continuous feeds through their gastrostomy tubes. These patients also have infrequent bowel movements that are not readily remedied with stools softeners and stimulant laxatives alone. Of course, there are other components of being confined to a wheelchair with decreased movement and general motility, that also affect GI motility negatively.
In my next post, I will discuss some of the interventions we use to treat GI motility disorders. Thanks for reading!