ESOPHAGOSTOMY TUBE (E-TUBE) (8 to 16 Fr.) may be placed in patients with disease or trauma to the nasal or oral cavity. The tip of the tube is placed
in the caudal esophagus, and the tube can be used for long-term (weeks to months) in-hospital or home feedings. For patients
in which the pharynx and esophagus must be bypassed, gastrostomy tubes (G-tube) (mushroom-tipped, 16 to 22 Fr.) can be placed
either intraoperatively or percutaneously using an endoscope or a G-tube introduction device.
GASTROSTOMY TUBES are recommended also for long-term feeding (weeks to months) if needed. G-tubes are convenient and safe for in-hospital and
at-home feedings. Any tube that has been placed into the esophagus or stomach allows bolus or meal-type feeding schedules
because the stomach acts as a food reservoir.
JEJUNOSTOMY TUBES (J-TUBES) (5 to 8 Fr.) are placed within the small intestine, ideally at the time of exploratory celiotomy, to bypass the proximal
GI tract. J-tubes may be placed by mini-laparotomy or by threading a small feeding tube through a larger E-tube or G-tube
where the tip of the smaller J-tube is in the jejunum.
A feeding tube with a tungsten-weighted tip may be threaded through the pylorus into the jejunum using an endoscope or during
a surgical procedure. A common complication with J-tubes is the tip re-entering the stomach by reverse peristalsis.
Selecting a food product
Food selection depends on tube size and location within the GI tract, the availability and cost of products and the experience
of the clinician. Commercial foods available for enteral use in veterinary patients can be divided into two major types: 1)
liquid products and 2) blended pet foods. Nasal and jejunostomy tubes usually have a small diameter (< 8 Fr.), which requires
use of liquid foods. Orogastric, E-tubes and G-tubes have large diameters (> 8 Fr.) and are suitable for liquid and blended
In general, human liquid foods cost more than veterinary liquid products and may be adequate for adult dogs, but not for long-term
(> 5 days) feeding of cats, puppies and adult dogs with increased protein losses (e.g., protein-losing drains or chest tubes).
Liquid foods are of two basic types: monomeric or polymeric. Foods said to be monomeric contain nutrients in small, hydrolyzed,
absorbable forms. The proteins are usually present as dipeptides or tripeptides or larger hydrolyzed protein fractions. The
fat source often is an oil of mixed (medium-and long-chain) fatty acids. The carbohydrate sources are mono-, di-and trisaccharides.
These monomeric products are homogenized liquids designed for human nutrition and can be fed through any feeding tube including
a J-tube. Monomeric foods are indicated in disease conditions such as inflammatory bowel disease, lymphangiectasia, refeeding
parvoviral enteritis, pancreatitis and any other condition in which a patient's digestive capabilities are impaired.
Polymeric products contain mixtures of more complex nutrients. Protein is supplied in the form of large peptides (e.g., casein
or whey). Carbohydrates are usually supplied as cornstarch or syrup, and fats are provided by medium-chain triglycerides (MCT)
or vegetable oil.
These foods require normal digestive function and are appropriate for most veterinary clinical situations, especially when
a small tube (< 8 Fr.) has been placed. Clinicare by Abbott is a polymeric product that meets the current AAFCO nutrient allowances
for adult dogs and cats. This product is a homogenized liquid containing 1 kcal/ml so volume fed in 24 hrs equals RER and
is usually accepted better than human liquid products containing MCT oil. This liquid food is the best option currently available
in North America because of the low (230 mOsm/kg) osmolality, nutritional profile, ease of use and versatility.
Blended pet foods
This category refers to commercial products that are nutritionally complete and balanced according to AAFCO allowances for
dogs and cats. Water is added typically for a consistency that flows through a feeding tube. Some products have a blended
texture, high water content and very small particle size, whereas others must be blenderized with water and may have to be
strained to remove particulate matter.
These products are more readily available, better tolerated and less expensive than the human liquid foods, and contain essential
amino acids and micronutrients properly balanced to the caloric density of the food. Fewer medical complications (e.g., diarrhea)
are likely to result.
Blended pet foods are appropriate for patients in catabolic states that are using fat and protein substrates from body stores.
Blenderized canned veterinary therapeutic foods can be an asset when feeding patients with specific disease conditions requiring
a specific nutrient profile (low phosphorous for example). Blenderized pet foods are more likely to plug a small feeding tube
if not properly flushed after feeding; however, the patient may continue oral consumption of the same pet food, eliminating
a diet change when the patient's appetite returns after the tube is removed.