Practice Guidelines For Gastrostomy Tubes

Small Animal

Small Animal Gastroenterology

The Compendium March 1997

PERSPECTIVES IN VETERINARY MEDICINE

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Practice Guidelines for Gastrostomy Tubes

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he use of tube gastrostomy for the nutritional support of dogs and cats is not a new idea. Techniques for surgical, endoscopic percutaneous, and blind (nonendoscopic) percutaneous placement have been described in the veterinary literature for more than a decade; however, use of these techniques has become more widespread only recently.1–3 More practitioners are now using gastrostomy tubes for a number of reasons. The important role that nutritional support plays in the survival and recovery of veterinary patients is becoming increasingly recognized. Many reports in the literature demonstrate that gastrostomy tubes are convenient and relatively safe when used for the purpose of nutritional support.3–7 In addition, the advent of veterinary formulas specifically developed for tube feeding is making nutritional support much simpler and more convenient for veterinarians and clients alike.

Gastrostomy tubes have several advantages over smallerbore nasogastric tubes. Blenderized pet food can be fed more easily, and patients are purported to better tolerate and be more comfortable with gastrostomy tubes. The principal disadvantage of gastrostomy tubes in comparison with nasogastric tubes is their relative complexity and invasiveness of insertion. The ability to place tubes percutaneously, by either endoscopic or blind techniques, has largely mitigated these disadvantages because tubes can be placed rapidly and without the need for a laparotomy. Because of their advantages, gastrostomy tubes have recently become an increasingly popular means of nutritional support for dogs and cats. This increase in popularity, however, has been associated with an increase in the number of complications. Most reported complications are minor—tubes become obstructed or localized edema or infection develops.3–9 Some complications, such as splenic laceration or inadvertent tube removal, however, can be very serious and can result in death.5–8,10 These unfortunate occurrences are reminders that gastrostomy tube placement is an invasive procedure that carries with it an inherent risk for

the patient. To minimize this risk, practices that use gastrostomy tubes should have clearly established guidelines for the indications, placement techniques, and management of these devices.

Indications Use of gastrostomy tubes should be reserved for patients that will need relatively longterm tube feeding. Neither surgically nor percutaneously placed tubes should be removed until secure adhesions have formed between the gas-

KEY POINTS

Kathryn E. Michel, DVM Department of Clinical Studies School of Veterinary Medicine University of Pennsylvania Philadelphia, Pennsylvania

Advantages and Disadvantages

may be required for adequate adhesions to form in these animals than in healthy animals. Therefore, it makes little sense to place a gastrostomy tube in a patient that is expected to resume voluntary food intake in less than 2 weeks. The other major indication for the use of gastrostomy tubes is in animals in which nasogastric (or pharyngostomy and esophagostomy) tubes are contraindicated, such as those with facial bone fractures or esophageal disease. It is important to bear in mind, however, that

■ Gastrostomy tubes can be used with convenience and relative safety for the provision of nutritional support for dogs and cats. ■ Gastrostomy tubes should be used for patients that need relatively long-term tube feeding and for those in which nasogastric tubes are contraindicated. ■ Percutaneous techniques for gastrostomy tube placement allow for rapid and relatively noninvasive insertion of these tubes.

tric and body walls. For percutaneously placed tubes, it has been recommended that the tube be left in place for a minimum of 7 to 10 days.7 If removal is to be by traction (as opposed to cutting the tube and allowing the tip to pass in the feces), a 14-day waiting period has been advised. 8 Wound healing in animals that are severely nutritionally depleted is often impaired, and more time

gastrostomy tube feeding places patients with neuromuscular abnormalities, such as megaesophagus or abnormal mentation, at risk of pulmonary aspiration of food if gastric reflux occurs.

Gastrostomy Tube Placement Gastrostomy tubes can be placed either surgically or percutaneously (Figure 1). Either

The Compendium March 1997

Small Animal

A

B

C

D

E

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Figure 1—(A and B) Percutaneous endoscopic gastrostomy tube placement. (C and D) Blind percutaneous gastrostomy tube placement using a specially designed device. (E ) Percutaneous (endoscopic or blind) gastrostomy tube being drawn through the body wall. (F) Mushroom-tip gastrostomy tube in place (illustrated with and without [inset] an inner flange).

Small Animal

The Compendium March 1997

MANUFACTURERS OF TUBES AND TUBE PLACEMENT DEVICES Urologic Catheters (balloon and mushroom tip) C.R. Bard, Inc Covington, GA 800-526-4455 Specific-Purpose Gastrostomy Tubes and Percutaneous Endoscopic Gastrostomy (PEG) Kits Cook Veterinary Products Bloomington, IN 800-826-2380 CORPAK MedSystems (Distributed by MILA) Erlanger, KY 606-371-6452 800-323-6305 Ross Products Division Abbott Laboratories Columbus, OH 800-231-3330 Blind Percutaneous Gastrostomy (BPG) Devices ELD Gastrostomy Tube Applicator Jorgensen Laboratories Loveland, CO 970-669-2500

approach requires general anesthesia, although the percutaneous techniques can be performed rapidly (in less than 10 minutes) by experienced practitioners. If an endoscope is available, the choice between performing a surgical gastrostomy versus a percutaneous gastrostomy depends primarily on whether the patient requires a laparotomy for reasons other than tube placement. Other situations in which a surgical approach is indicated are when a patient has an oropharyngeal or esophageal obstruction or when a patient is obese. If an endoscope is not available, us-

ing a blind technique for percutaneous gastrostomy tube insertion is an option. Some of the techniques for blind percutaneous gastrostomy (BPG) require special devices for guiding tube insertion, whereas others simply use a piece of vinyl tubing.3,8,9,11 (The purchase of a specially designed instrument for BPG is insignificant when compared with the cost of an endoscope.) The risks associated with BPG are similar to those seen with percutaneous endoscopic gastrostomy (PEG): inadequate tube tension resulting in inadequate adhesions to the gastric

and body walls, excessive tube tension resulting in pressure necrosis of the gastric and body walls, and inadvertent perforation or displacement of abdominal organs (such as the spleen or colon). The use of an endoscope helps to decrease these risks by allowing both direct visualization of the process and insufflation of the stomach with air. To date, the reported complication rate for BPG is similar to that of PEG. However, a recent study found a greater likelihood of penetration of the visceral surface of the stomach and the deep leaf of the omentum when BPG tubes were placed either without any gastric insufflation or when the stomach was insufflated after the guide tube had been positioned against the lateral abdominal wall. 11 Although this was a nonsurvival study, the investigators believed that tube malpositioning of this sort could lead to potential injury of intraabdominal organs. The stomach was insufflated using an orogastric tube connected to an electric air compressor. Gastric insufflation prior to positioning the guide tube against the lateral abdominal wall resulted in more consistent and safer tube placement.

Tube Selection Gastrostomy tubes used in veterinary patients (see Manufacturers of Tubes and Tube Placement Devices) have traditionally been designed as urologic catheters (e.g., balloon-tip and mushroom-tip catheters). These tubes are inexpensive and readily available. Mushroom-tip catheters have been successfully adapted for use as PEG tubes and seem to with-

stand the gastric environment for weeks or even months without deterioration. The balloon-tip catheter is generally used for surgical insertion; the safety of this procedure depends to some degree on the integrity of the balloon. Relatively inexpensive balloontip catheters that have been specifically designed as gastrostomy tubes are now available. Because serious complications can occur if the balloon ruptures before adhesions have formed, practitioners should consider using the specific-purpose rather than the urologic balloon-tip catheters for surgical insertion. Tubes are available in a wide range of sizes; 18 or 20 Fr for cats and small dogs and 24 Fr for larger dogs should usually suffice. Using smaller tubes has two drawbacks. First, smallerbore tubes negate one of the chief advantages of the gastrostomy tube, that is, ease of feeding blenderized pet foods. Second, recent clinical reports suggest that when tubes 18 Fr or larger are used, it is not necessary to use an inner flange.7,8 When PEG tube insertion was first described for small animals, use of an inner flange was recommended for added security in preventing the tube from migrating out of the stomach. The disadvantage of using an inner flange, at least in cats and small dogs, is the risk of gastrointestinal obstruction if the flange is not retrieved endoscopically.7

Tube Management Feeding protocols and management of tube-related complications have been reviewed extensively.12,13 Several important issues related to tube man-

The Compendium March 1997

agement, however, are often overlooked. The first issue concerns tube labeling. Proper identification of feeding tubes is critical in patients that have multiple tubes (e.g., chest tubes or biliary stents). Very often, these patients have extensive body wraps, and the origin of the tube is not readily apparent. When inserted, the tube should also be marked at the point where it exits the skin. This mark will aid in assessing whether the tube has migrated or been dislodged. The second issue concerns medical recordkeeping. Complete records should include a description of the placement technique, the type and size of tube, and whether an inner flange was used. This informa-

Small Animal

tion is necessary to ensure that any complications that arise are addressed appropriately and that, when the animal resumes eating, tube removal is accomplished safely.

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References 1. Crane SW: Placement and maintenance of a temporary feeding tube gastrostomy in the dog and cat. Compend Contin Educ Pract Vet 2(10):770–776, 1980. 2. Bright RM, Burrows CF: Percutaneous endoscopic tube gastrostomy in dogs. Am J Vet Res 49:629–633, 1988. 3. Fulton RB, Dennis JS: Blind percutaneous placement of a gastrostomy tube for nutritional support in dogs and cats. JAVMA 201:697–700, 1992. 4. Bright RM, Oransinski EB, Pardo AD, et al: Percutaneous

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tube gastrostomy for enteral alimentation in small animals. Compend Contin Educ Pract Vet 13(1):15–22, 1991. Armstrong PJ, Hardie EM: Percutaneous endoscopic gastrostomy—A retrospective study of clinical cases in dogs and cats. J Vet Intern Med 4:202–206, 1990. Jacobs G, Cornelius L, Allen S, et al: Treatment of idiopathic hepatic lipidosis in cats: 11 cases (1986–1987). JAVMA 195:635– 638, 1989. DeBowes LJ, Coyne B, Layton CE: Comparison of french-pezzar and Malecot catheters for percutaneously placed gastrostomy tubes in cats. JAVMA 202:1963–1965, 1993. Mauterer JV, Abood SK, Buffington CA, Smeak DD: New technique and management guidelines for percutaneous nonendoscopic tube gastrostomy. JAVMA 205:

574–579, 1994. 9. Mark SL, Rishniw M, Henry CJ, et al: Blind percutaneous gastrostomy: A new technique. Proc 12th ACVIM Forum:981, 1994. 10. Miller MA, Allen SW: What is your diagnosis? JAVMA 207: 1283–1284, 1995. 11. Clary EM, Hardie EM, Fischer WD, et al: Nonendoscopic antegrade percutaneous gastrostomy: The effect of preplacement gastric insufflation on tube position and intra-abdominal anatomy. J Vet Intern Med 10:15–20, 1996. 12. Wheeler SL, McGuire BH: Enteral nutritional support, in Kirk RW (ed): Current Veterinary Therapy. X. Philadelphia, WB Saunders Co, 1989, pp 30–37. 13. Armstrong PJ, Hand MS, Frederick GS: Enteral nutrition by tube. Vet Clin North Am Small Anim Pract 20:237–275, 1990.