From Wikipedia, the free encyclopedia - View original article
A feeding tube is a medical device used to provide nutrition to patients who cannot obtain nutrition by mouth, are unable to swallow safely, or need nutritional supplementation. The state of being fed by a feeding tube is called gavage, enteral feeding or tube feeding. Placement may be temporary for the treatment of acute conditions or lifelong in the case of chronic disabilities. A variety of feeding tubes are used in medical practice. They are usually made of polyurethane or silicone. The diameter of a feeding tube is measured in French units (each French unit equals 0.33 millimeters). They are classified by site of insertion and intended use.
There are dozens of conditions that may require tube feeding. The more common conditions that necessitate feeding tubes include prematurity, failure to thrive (or malnutrition), neurologic and neuromuscular disorders, inability to swallow, anatomical and post-surgical malformations of the mouth and esophagus, cancer, and digestive disorders.
The most common types of tubes include those placed through the nose, including Nasogastric, Nasoduodenal, and Nasojejunal tubes, and those placed directly into the abdomen, such as a Gastrostomy, Gastrojejunostomy, or Jejunostomy feeding tube.
A nasogastric feeding tube or NG-tube is passed through the nares (nostril), down the esophagus and into the stomach. This type of feeding tube is generally used for short term feeding, usually less than a month, though some infants and children may use an NG-tube longterm. Individuals who need tube feeding for a longer period of time are typically transitioned to a more permanent gastric feeding tube. The primary advantage of the NG-tube is that it is temporary and relatively non-invasive to place, meaning it can be removed or replaced at any time without surgery. NG-tubes can have complications, particularly related to accidental removal of the tube and nasal irritation.
Pilot research explores the possibilities of guiding patients to self-intubate with NG-tubes.
A Nasojejunal or NJ-tube is similar to an NG-tube except that it is threaded through the stomach and into the jejunum, the middle section of the small intestine. In some cases, a nasoduodenal or ND-tube may be placed into the duodenum, the first part of the small intestine. These types of tubes are used for individuals who are unable to tolerate feeding into the stomach, due to dysfunction of the stomach, impaired gastric motility, severe reflux or vomiting. These types of tubes must be placed in a hospital setting.
A gastric feeding tube (G-tube or "button") is a tube inserted through a small incision in the abdomen into the stomach and is used for long-term enteral nutrition. One type is the percutaneous endoscopic gastrostomy (PEG) tube which is placed endoscopically. The position of the endoscope can be visualized on the outside of the patient's abdomen because it contains a powerful light source. A needle is inserted through the abdomen, visualized within the stomach by the endoscope, and a suture passed through the needle is grasped by the endoscope and pulled up through the esophagus. The suture is then tied to the end of the PEG tube that will be external, and pulled back down through the esophagus, stomach, and out through the abdominal wall. The insertion takes about 20 minutes. The tube is kept within the stomach either by a balloon on its tip (which can be deflated) or by a retention dome which is wider than the tract of the tube. G-tubes may also be placed surgically, using either an open or laparoscopic technique.
Some individuals continue to use a long, catheter-like tube, while others use a small "button" with a detachable extension set for feedings. Most G-tubes can be changed easily at home. Gastric feeding tubes are suitable for long-term use, though they sometimes need to be replaced if used long term. The G-tube can be useful where there is difficulty with swallowing because of neurologic or anatomic disorders (stroke, esophageal atresia, tracheoesophageal fistula), and to avoid the risk of aspiration pneumonia. However, in patients with advanced dementia or adult failure to thrive it does not decrease the risk of pneumonia.
A G-tube may instead be used for gastric drainage as a longer term solution to the condition where blockage in the upper reaches of the small intestine causes bile and acid to accumulate in the stomach, typically leading to periodic vomiting. Where such conditions are only short term, as in a hospital setting, a nasal tube connected to suction is usually used. A blockage lower in the intestinal tract may be addressed with a surgical procedure known as a colostomy, and either type of blockage may be corrected with a bowel resection under appropriate circumstances. If such correction is not possible or practical, nutrition may be supplied by parenteral nutrition.
A gastrojejunostomy or GJ feeding tube is a combination device that includes access to both the stomach and the jejunum, or middle part of the small intestine. Typical tubes are placed in a G-tube site or stoma, with a narrower long tube continuing through the stomach and into the small intestine. The GJ-tube is used widely in individuals with severe gastric motility, high risk of aspiration, or an inability to feed into the stomach. It allows the stomach to be continually vented or drained while simultaneously feeding into the small intestine. GJ-tubes are typically placed by an Interventional Radiologist in a hospital setting. The primary complication of GJ-tube is migration of the long portion of the tube out of the intestine and back into the stomach.
A jejunostomy feeding tube (J-tube) is a tube surgically or endoscopically inserted through the abdomen and into the jejunum (the second part of the small intestine). Please note that alternatively a jejunostomy commonly refers to a surgical fistula created connecting the jejunum or the abdominal wall. There are several techniques for placement, including a direct surgical or endoscopic technique, or a more complicated Roux-en-Y procedure. The J-tube may use a long, catheter-like tube or a button. Depending on the placement type, the tube may be changed at home, or may need to be changed at a hospital. A J-tube is helpful for individuals with poor gastric motility, chronic vomiting, or at high risk for aspiration and in those in whom gastrostomy tubes are contraindicated.
The effectiveness of feeding tubes varies greatly depending on what condition they are used to treat.
Feeding tubes are used widely in children with excellent success for a wide variety of conditions. Some children use them temporarily until they are able to eat on their own, while other children require them longterm. Some children only use feeding tubes to supplement their oral diet, while others rely on them exclusively.
Patients with advanced dementia who are unable to feed themselves should have another person feed them in preference to the medical intervention of having a feeding tube. In such patients, feeding tubes do not increase life expectancy or protect the patient from aspiration pneumonia. Feeding tubes can also cause pressure ulcers, require pharmological or physical restraints, and lead to patient distress. There is evidence which shows that patients who get feeding assistance rather than tubes have better outcomes. In the final stages of dementia, assisted feeding may still be preferred over a feeding tube to bring benefits of palliative care and human interaction even when nutritional goals are not being met.
Patients with the eating disorder anorexia nervosa may be tube fed if they are significantly malnourished. This can be voluntary or in some cases where the patient is resistant to feeding under the force of the Mental Health Act. Patients may tamper with their feeds, which can interfere with the effectiveness of feeding.
Nasogastric tubes are often used in the intensive care unit (ICU) to provide nutrition to critically ill patients while their medical conditions are addressed. There is moderate evidence for use of feeding tubes in the ICU, especially if requiring mechanical ventilation for more than three days.
There is at least moderate evidence for feeding tubes improving outcomes for chronic malnutrition in patients with cancers of the head and neck, acute stroke while the patient undergoes rehab, and ALS.
The nasogastric (NG) tube is meant to convey liquid food to the stomach. Thus, its tip must rest in the stomach. When inserted incorrectly, the tip may rest in the respiratory system instead of the stomach; in this case, the liquid food will enter the lungs, resulting in pneumonia and death. The incorrect insertion of fine nasogastric tube which are stiffened with a wire has been associated with the puncture of the lungs and pneumothorax; however this is a rarer complication.
The gastrostomy tube is associated with its own set of complications. Leakage of gastric contents (containing hydrochloric acid) around the tube into the abdominal (peritoneal) cavity results in peritonitis, a serious complication which will cause death if it is not properly treated. Minor leakage may cause irritation of the skin around the gastrostoma. Barrier creams, to protect the skin from the corrosive acid, is generally recommended.
All feeding tubes will eventually need to be changed because of wear and tear, or a clogged lumen. The change of a gastrostomy tube is not without risks. The loop-gastrostomy tube is a recent innovation which minimizes the risks of tube change.
The K-E diet (short for Ketogenic Enteral diet) involves being tube-fed a "Ketogenic diet" of carbohydrate free mixture of protein and fats, adding up to 800 calories a day. The 10-day treatment was created by the Florida based Dr. Oliver Di Pietro for people who want to lose weight. It received a great deal of publicity because of an article in the New York Times about a bride who did the K-E diet to fit into a dress for her wedding. It has also attracted criticism from experts who have described the diet as "stupid" and "outrageous".