Page 640 - Fluid, Electrolyte, and Acid-Base Disorders in Small Animal Practice

Enteral Nutrition 627

complications associated with overfeeding, we determine TABLE 26-2 Vitamin and Mineral
initial estimates of energy needs on the basal requirement Requirements (per
for the current body weight of the animal. Studies in
humans suggest that metabolic rates greater than twice 1000 kcal) of the Young
the basal requirement rarely occur, even in severely Growing Dog and Cat
injured patients. In addition, overestimating nutrient U.S. RDA
needs increases the risk of the patient for problems Children
associated with overfeeding. Substance (1-3 Yr) Cats Dogs
The protein requirements of critically ill patients are
not known. The protein requirements of young animals Vitamins
for growth are approximately 17% to 22% of total Vitamin A 1320 IU 670 IU 1011 IU
calories, 87 and we use this guideline as an estimate for Vitamin D 400 IU 100 IU 110 IU
patients fed liquid-formula diets containing high-quality Vitamin E 6 IU 6 IU 6.1 IU
protein. Commercial pet foods may have lower protein Vitamin K 15 IU 20 IU NA
quality and digestibility. If such diets are fed, higher pro- Thiamin 0.7 mg 1.0 mg 0.28 mg
tein concentrations (25% to 40% of calories) are required. Riboflavin 0.8 mg 0.8 mg 0.70 mg
Niacin 9.0 mg 8.0 mg 3.1 mg
We have used liquid diets containing 17% to 20% of
Pyridoxine 1.0 mg 0.8 mg 0.3 mg
kilocalories as protein in small animal patients with severe
Folate 50 mg 0.16 mg 56 mg
chronic renal failure successfully for short periods (<2
Vitamin B 12 0.7 mg 4.0 mg 7.0 mg
weeks), and have not found further restriction to be nec- Minerals
essary. Patients with protein-losing diseases (e.g., pro- Calcium 800 mg 160 mg 1666 mg
tein-losing enteropathy or nephropathy) should have Phosphorus 800 mg 120 mg 1246 mg
their estimated losses replaced. Protein losses by patients Magnesium 80 mg 80 mg 115 mg
with protein-losing nephropathy are small relative to daily Zinc 10 mg 10 mg 10 mg
needs. 19 In contrast, burned patients may lose significant Iron 10 mg 16 mg 9.1 mg
amounts of protein, which may be replaced using diets Iodine 70 mg 70 mg 168 mg
containing higher percentages of kilocalories as protein. 64
NA, not available.
Hospitalized patients also require essential fatty acids,
minerals, and vitamins. Specific vitamin and mineral
needs depend on the type and severity of the underlying
disease process. For short-term nutritional supplementa- recorded daily to evaluate adequate nutrition. Electronic
tion, at least sodium, chloride, potassium, phosphate, scales that weigh to the nearest gram are inexpensive, and
calcium, and magnesium should be provided. Provision allow the food and its container to be weighed in and out
of supplemental zinc should also be considered, especially of the cage.
in anorexic patients with gastrointestinal disease, where Dry, adult pet foods contain between 325 to 450 kcal
losses may be increased. 102 Zinc also is important because per 8 oz and canned foods contain approximately
of its role in protein synthesis, immune function, in vitro 1 kcal/g. To estimate the adequacy of food intake, mul-
phagocytic activity, and taste and smell. 82 Liquid enteral tiply the caloric density of the food by the amount eaten.
diets for nutritional support contain all the necessary If the result is less than two thirds of the goal intake,
minerals; so additional supplementation probably is not nutritional support by means of an enteral feeding tube
warranted. No studies have specifically evaluated the may be necessary.
needs of veterinary patients for these nutrients. At pres- Nursing techniques to improve and encourage food
ent, provision of vitamins at or near the National intake are the simplest methods of nutritional support.
Research Council requirements for growth seems reason- If it is possible for owners to bring food from home
able in the absence of any specific contraindication 77 and feed the patient out of its cage, this should be
(Table 26-2). encouraged. Elizabethan collars should be removed
under supervision when tempting an animal to eat. Pet-
APPETITE STIMULATION ting and vocal reassurance when food is offered may
induce some animals to begin eating again. Warming
The primary objective of nutritional support is to reestab- food to body temperature to enhance aroma or changing
lish voluntary food intake. When enteral feeding the type of food offered may help. If the animal’s nasal
techniques of nutritional support are necessary, they passages are occluded by exudates, cleaning them with
should only be used until the animal is eating adequate warm water or saline may improve olfaction.
calories voluntarily. Food must be offered regularly to When introducing a new food to ill patients, care
evaluate appetite. Food intake of hospitalized patients should be taken to minimize the possibility of creating
should be measured and calorie intake should be a learned food aversion. A learned aversion is the