Percutaneous Endoscopic Stomas for Enteral Feeding and Drainage
Percutaneous Endoscopic Stomas for Enteral Feeding and Drainage
The use of safe and cost-effective endoscopic techniques for the placement of tubes in the gastrointestinal tract has led to increased utilization of long-term enteral feeding in patients with impaired GI function, including many cancer patients. Of an estimated 148,000 US patients who received long-term enteral feeding outside hospitals in 1992, 43% were cancer patients. The technique of percutaneous endoscopic gastrostomy is used primarily for enteral feeding, but can also be used to place wide tubes for drainage of an obstructed GI tract. Aspiration problems can be eliminated by endoscopic placement of a feeding tube directly into the jejunum (percutaneous endoscopic jejunostomy). Patients with advanced cancer who are not surgical candidates may benefit from an external GI bypass placed endoscopically, which allows drainage through a gastrostomy and feeding through a jejunostomy distal to the obstruction.
The idea that nutrients can be introduced into the gastrointestinal (GI) tract through a route other than the mouth is not new. This practice was started by the ancient Egyptians, who used nutrient enemas for preservation of general health. Greek physicians prescribed enemas containing milk and wine for treatment of diarrhea . The introduction of nutrients into the rectum continued in Western medicine until its inadequacies were outlined at the beginning of this century .
Attempts to fashion tubes for placement in the upper GI tract originated in Venice in the 16th century, with the use of tubes made from animal bladder that were placed in the esophagus. A major development occurred at the end of the 18th century when a tube made of eel skin was used for 5 weeks to feed a patient with neurogenic dysphagia . The use of nasogastric tubes for feeding or emptying the stomach became widespread in the 19th century. Thereafter, surgical gastrostomies and jejunostomies along with nasogastric tubes were used for these purposes.
The introduction of endoscopic techniques for the placement of tubes in the GI tract in the last 15 years has revolutionized the approach to enteral feeding and presented opportunities to improve the quality of life of patients, particularly those with impairment of GI function because of cancer. Although gastrostomy and jejunostomy tubes have been placed for many years by surgical techniques, the relatively high morbidity and mortality [3-5], and the requirement for an operating room have limited their use. In the last decade, there has been a marked increase in utilization of long-term enteral feedings. The Oley Foundation estimated that in 1992, 148,000 patients across the United States received long-term enteral feeding outside hospitals; 43% of these patients had cancer . This increase can be attributed mainly to the development of simple, safe, and cost-effective endoscopic techniques for placement of tubes in the GI tract, and to the availability of a wide range of low-cost commercial enteral feeding solutions.
Gauderer and Ponsky  introduced the technique for placement of a percutaneous endoscopic gastrostomy (PEG) in 1980. This method has become so popular that, in 1990, it was reported to be the second most common indication for upper GI endoscopy in hospitalized patients . Various modifications of the original technique have been reported, along with techniques for placement of tubes directly into the jejunum . The majority of tubes placed in the upper GI tract endoscopically are used for enteral feeding. However, this technique can also be used to place wide tubes for drainage of an obstructed GI tract . The technique involves the introduction of a thread or a guide-wire into the stomach or jejunum, which is used either to pull or push a tube through the mouth, esophagus, stomach, and abdominal wall.
Pull and Push Methods
The method of placement of a percutaneous endoscopic gastrostomy has been described in numerous reports [7,11-14]. The patient first undergoes a routine upper GI endoscopy. The stomach is then inflated, pushing the gastric wall against the abdominal wall. When the lights in the endoscopy room are dimmed, the light from the tip of the scope in the stomach can be seen transilluminating the abdominal wall. The transillumination identifies the part of the anterior gastric wall that is positioned directly against the abdominal wall. This is a safe area for the placement of the gastrostomy tube. After application of a local anesthetic, a 5-mm incision is made in the skin. A 16-gauge, smoothly tapered Medicut catheter is inserted through the incision into the stomach. The metal guiding stylet is removed, and a thread (pull method) or guide-wire (push method) is passed through the catheter.
Pull Method--In the pull method, the thread is grasped by a biopsy forceps or a snare (passed through the scope), and the endoscope is withdrawn, pulling the thread with it through the mouth. Thus, the thread passes through the abdominal wall, stomach, esophagus, and pharynx, and exits through the mouth.
The gastrostomy tube may range in size from 15 F to 28 F. One end of the tube has a widened mushroom shape, and the other end is attached to a tapered plastic or rubber dilator, the tip of which is hooked to a thread or wire. The thread exiting through the mouth is tied to the thread on the tapered end of the tube. The end of the thread exiting through the abdominal wall is pulled, moving the tube through the mouth into the stomach. The tapered dilator of the tube is then pulled through the abdominal wall, creating the channel through which the tube exits.
The endoscope is reintroduced, and, under endoscopic visualization, the tube is pulled out further until the mushroom end is positioned firmly against the gastric wall. The gastric and abdominal walls are secured firmly against each other by placing a bumper on the tube at the point where it exits from the abdominal wall.
The Push Method--In the push method , instead of a thread, a guide-wire is brought out of the patient's mouth. A Sachs-Vine tube is pushed over the guide-wire until the dilator tip exits through the abdominal wall.
The performance of percutaneous endoscopic gastrostomies has been found to be safe, with a morbidity rate of 3% to 15% and mortality of 0.3% to 1% [11-15]. The tubes function well in the long-term, with very few complications .
Indications for Placement
Table 1 shows the indications for placement of a feeding gastrostomy tube. Among cancer patients, the most common indications are cancer of the head and neck with obstruction and or severe dysphagia. Originally, prior abdominal surgery was considered a contraindication for the placement of percutaneous endoscopic tubes. However, it is clear now that the procedure can be performed effectively and safely in patients who have undergone major abdominal operations, as well as in those with disseminated abdominal carcinomatosis and ascites [9,10,15,16].
Successful long-term enteral feeding requires that the patient and a family member be trained thoroughly to perform the feeding safely and avoid complications, particularly aspiration. It is also essential to establish an orderly medical follow-up program, to ensure that the patient is adequately nourished and that problems arising from the feeding are appropriately addressed. Feeding through a gastrostomy tube can be accomplished by infusing boluses of 300 cc to 500 cc, three to four times a day. In this system, up to 3,000 calories can be provided safely.
With the increase in survival in patients on long-term enteral nutrition, issues of quality of life, comfort, and esthetics have become important. Although a percutaneous endoscopic gastrostomy offers these patients a simple and convenient access for feeding, the protruding tube can get caught in clothes, is esthetically unappealing, and interferes with sexual activity and body image. The skin level button gastrostomy (Figure 1) offers an advantage by eliminating the protruding tube [17-19]. This device is particularly advantageous in cancer patients with good performance status who have severe dysphagia and require long-term enteral feeding .
Placement of a button gastrostomy requires a mature gastrocutaneous or jejunocutaneous fistula and is usually performed 4 to 6 weeks after the initial placement of a percutaneous endoscopic gastrostomy or jejunostomy tube. Technically, the button is placed by stretching it over a metal stylet, which is then pushed through the fistula into the stomach. Safety considerations require that an upper GI endoscopy be performed so that the stomach can be distended prior to insertion. The endoscopy also ascertains that the button is appropriately placed inside the stomach . The device functions well long-term, and requires replacement on average only after 1½ to 2 years .