Feeding tube management and complications
We are all familiar with the use of feeding tubes for cats with hepatic lipidosis, but how many times do we deal with the older animal with no obvious physical problem other than an unwillingness to eat adequate amounts of food? What about the animal that is hit by a car and has a jaw fracture that is making eating difficult or impossible? There are many scenarios routinely seen in practice and could benefit from placement of a feeding tube.
Types of tubes
The most commonly placed feeding tubes are nasoesophageal, esophageal, gastrostomy, and jejunostomy. Esophageal tubes can be placed using minimal equipment following standard technique practices. Gastrostomy tubes can be placed blind using specialized equipment, placed with the aid of a gastroscope or surgically.
Feeding can be started immediately with a nasoesophageal tube, and within 12 hours with esophageal, gastrostomy, and jejunostomy tubes. This delay allows a temporary stoma to form around the tube insertion site prior to feeding.
There are multiple veterinary recovery diets that are available in a gruel form that pass easily through most of the larger bore feeding tubes (12 fr and higher). Sometimes adding as little as 1-2 tablespoons (15-30 ml) per can of food will greatly increase ease of passage.
Mechanical complications
Mechanical complications include both tube obstruction and premature removal of the tube or dislodgement from the site of placement. The most common problem, tube obstruction, can be prevented in most cases by proper tube maintenance. Food should never be allowed to sit in the tube, and the tube should be flushed with warm water after every feeding, or whenever gastrointestinal contents are aspirated through the tube, such as when checking residuals. Choosing the most appropriate tube for the animal best prevents premature tube removal or dislodgement, using an elizabethan collar and wraps when appropriate.
Gastrointestinal complications
Some of the gastrointestinal complications seen with tube feeding are related to the feeding itself. Food that is administered too quickly, in too large an amount, or at the wrong temperature, can cause nausea, vomiting, and/or abdominal discomfort. These signs can also be related to the patient’s underlying disease process or to a complication from the medications the patient is receiving.
Liquid enteral diets are typically very low residue, and are likely to cause soft stools or diarrhea in a normal animal, let alone one that is already ill. Canned pumpkin, 5-15 ml per feeding, will usually resolve the diarrhea. This can be prepared in ice cube trays and stored in a freezer bag until needed.
Constipation is not an unusual complication seen in patients with feeding tubes. Adding 1-2 ml lactulose per meal to the diet will often solve this problem; adjustments can be made as needed to maintain stool consistency.
Metabolic complications
There are two types of metabolic complications that patients can develop. The first is a result of the patient’s inability to assimilate certain nutrients. This can best be anticipated by doing a proper nutritional assessment of the patient before developing the nutritional plan. When reintroducing food after a period of fasting, several areas need to be monitored closely to prevent “Refeeding Syndrome”. During recovery, excessively rapid refeeding (or hyperalimentation) can overwhelm the patient’s already limited functional reserves.
Metabolic complications of any type are less likely to occur if estimated caloric needs are conservative. Current recommendations are to initiate feeding at caloric amounts equal to the patient’s calculated resting energy requirements without the addition of any “illness requirements”.
Infectious complications
The types of infectious complications that can occur in tube-fed patients include contamination of enterally fed formulas, peristomal cellulitis, septic peritonitis, and aspiration pneumonia.
Microbial contamination of food is easily avoided by following basic hygiene in preparation and storage of the food. Blended foods should be prepared daily, and opened commercial liquid diets should be kept refrigerated and discarded after 48 hours. When food is being delivered via a syringe pump, no more than 6 hours worth of food should be set up at a time. The equipment used to deliver the food should also be replaced every 24 hours; this includes syringes and delivery tubes and if the food is hung, the administration bag.
Peristomal cellulites can be seen with esophagostomy, gastrostomy, and jejunostomy tubes. This can usually be avoided by ensuring that the tube is not secured too tightly to the body wall, and by keeping the site clean and protected. Septic peritonitis can develop in patients if the gastrostomy or jejunostomy tube has become dislodged or removed before a permanent stoma has formed. Wraps or elizabethan collars may be necessary to prevent the patient from accidentally, prematurely, or intentionally removing the tube. Ensuring that a mature stoma has formed prior to tube removal can help to prevent peritonitis. Aspiration pneumonia can be seen with patients that have previously developed aspiration pneumonia, patients with impaired mental status, patients with neurologic injuries, patients with reduced or absent cough or gag reflexes, and those on mechanical ventilation.
Hospital management
Patients should be allowed out to exercise for 20-30 minutes approximately 1 hour before feeding, 2-3 times daily. Exercise has been found to greatly enhance both gastric motility and patient attitude.
Very few patients do poorly after discharge, particularly if good communication is established with the owners and regular rechecks are scheduled. Rechecks should be scheduled with the technician managing the case for every 2 weeks until the tube is removed.
Potential post discharge complications
Granulation tissue normally forms around the tube site on the outside and may be quite pink and can even bleed when handled. It is important to let clients know this is normal and expected; this tissue is what allows the hole to close after the tube is removed.
For patients that chew on the tube, a simple solution is to dress them in a close-fitting t-shirt that has a fitted neck.
The tube can be removed after the patient has reached the desired weight, has recovered from the trauma, or has finished chemotherapy treatment and has been totally self-feeding for 2 weeks without showing any signs of weight loss. Many feeding tubes can be maintained long-term, and the same stoma hole used for repeated tube placements.
Conclusion
Typically owners are very happy with the results they see when a feeding tube is used, and more importantly, the animal feels much better. Feeding tubes do require routine daily care and maintenance, but their use can extend a patient’s lifespan and improve their quality of life.
This article is based on a presentation given by Ms. Wortinger at the North American Veterinary Conference in Orlando, FL.CVT
