Robert McMichael is a neurologist at Neurology Associates of Arlington, Texas, where he directs the MDA clinic. McMichael, who was profiled in Quest, vol. 6, no. 2, has limb-girdle muscular dystrophy and 16 years of experience in treating people with neuromuscular disorders, including ALS.
Q: What is a feeding tube? Why does it have so many confusing names?
A: A feeding tube is a small, flexible tube, about the diameter of a pencil, used to allow liquid nourishment to enter the stomach directly, bypassing the mouth, throat and esophagus. The feeding tube is often called a PEG tube, which stands for percutaneous (through the skin) endoscopic (into the GI tract) gastrostomy (hole in the stomach) tube. It's also simply called a gastrostomy tube, or g tube.
Q: Why consider a feeding tube in ALS?
A: Many people who have ALS will develop dysphagia (difficulty swallowing) at some point. Swallowing can go from adequate to significantly impaired in months. This can lead to malnutrition and weight loss from inadequate protein and calorie intake. When this occurs, the body uses muscle as a source of energy and protein. This accelerates the progression of weakness.
A feeding, or PEG, tube can restore adequate protein and calorie intake.
One of the risks of dysphagia is that food or liquid taken through the mouth may go down the trachea (windpipe), rather than down the esophagus to the stomach. This is called aspiration. Aspiration causes a high risk of infection in the lungs (pneumonia). Thin liquids and foods that crumble are especially likely to be aspirated.
Q: What's the right time to put in a feeding tube?
A: Because of the nutritional deficiencies and the risk of aspiration, I prefer placing a PEG relatively soon after dysphagia symptoms begin. Another reason for placing the PEG early is that progression of respiratory weakness often parallels the dysphagia. When respiratory function is better, the procedure can be done with less difficulty and less risk of respiratory problems immediately following tube placement.
Q: Can you still eat and drink if you have a PEG tube?
A: The gastrostomy tube creates an alternate route of entry into the stomach but doesn't affect oral intake. In the early stages of dysphagia, it can be used to supplement oral intake of food and fluids. Later on, when it's dangerous or impossible to consume any food or drink orally, it can be used as the sole method of nutrition. Many readily available liquid pre- parations designed to provide a complete and balanced diet can be used as the sole source of nutrition.
Q: Can medication be given through a PEG?
A: When a person has trouble swallowing, he may be unable to swallow pills. Many medications can be crushed, dissolved and given through the PEG. Some capsules can be opened and sprinkled into water or liquid food. Medication taken this way should be well mixed with water, so that it doesn't remain in the tube, where it might get hard and block it.
If there is a liquid preparation of a medication, it can easily be administered through the tube.
Some medications come in patches and are absorbed through the skin. These include certain hormone supplements, some heart medications (nitroglycerin) and one blood pressure medication.
Check with your doctor or pharmacist about alternative preparations of medications.
Q: What about heartburn?
A: When gastroesophageal reflux (movement of food or liquids up from the stomach into the esophagus) is a problem, drugs to reduce acid release are useful.
Drugs to reduce acid release are useful if there is any problem with gastritis (stomach inflammation) or reflux. Gastritis and reflux aren't caused by ALS, but they're very common and can result in stomach pain or heartburn when using a PEG tube.
Q: What's involved in placing a PEG tube?
A: Placement of a gastrostomy tube generally takes about half an hour. The procedure can be done with heavy sedation and local anesthesia, or under general anesthesia. Most people experience moderate pain for up to several days after tube placement. This pain can generally be relieved well with pain medication.
I prefer to admit patients to the hospital a day in advance of placing the PEG. This permits me to use intravenous fluids to correct dehydration and to give respiratory treatments to maximize lung function. Generally, I don't begin tube feeding until the day after placement of the PEG tube. Keeping the patient in the hospital after placing the PEG also permits teaching the patient and family how to use the PEG.
The insertion procedure is generally performed by a gastroenterologist (stomach specialist).
Q: Is the PEG tube noticeable?
A: The PEG tube is cosmetically good. Most people use it several times a day, the same as taking meals. When not being used, the PEG tube can be placed into a loop and taped flat against the abdomen. It's easily concealed by clothing.
Q: What happens if the PEG tube accidentally comes out?
A: If the PEG tube is accidentally pulled out, it can usually be replaced easily at an emergency room with a Foley catheter, the commonly used bladder catheter. Because of the way the PEG tube is designed, it's not possible to push it back in from the outside. The Foley catheter has a bulb at the tip that is inflated after it's inserted to hold it in, so it can be inserted from the outside. This is easy to do, and no anesthesia or sedation is needed. However, it should be done within hours of a PEG or Foley coming out; if you wait until the next day, the small hole from the skin to the stomach may already be sealing up and it may not be possible to insert a Foley from the outside. If the hole does seal up, a new PEG can be put in by the same method as the original PEG.
Q: How do most people like the PEG tube?
A: My experience has been that after receiving a PEG, most people decide that it was a good decision.
Q: Are there alternatives to the PEG tube, such as dilating the esophagus?
A: You may have heard about esophageal dilation. Some neuromuscular diseases affect the muscles of the esophagus enough to cause the food bolus (chunk) not to travel down the esophagus well. Myotonic dystrophy and polymyositis are examples of conditions that can do this. Also, some muscle diseases can affect the smooth (involuntary) muscle of the lower esophagus. Sometimes, in these conditions, dilating the esophagus helps. Dilating the esophagus is not likely to help people who have ALS, as their swallowing problems are in the mouth and the throat, rather than the esophagus.