Page 462 - Small Animal Internal Medicine, 6th Edition

434 PART III Digestive System Disorders

is not vomiting) and the intestinal mucosa has reasonable
villus function. Absorption primarily occurs in the mature BOX 28.1
VetBooks.ir epithelium near the villus tip. Various products for use in Examples of Commercial “Bland” (Highly Digestible)*
people are commercially available, and there are also recipes
Diets
for making these solutions. Failure to monitor the patient or
follow instructions may lead to severe hypernatremia. Hill’s Prescription Diet i/d
The type of fluid therapy used in hypoproteinemic animals Iams Intestinal Plus Low-Residue
depends on the degree of hypoalbuminemia. Excessive fluids Purina CNM EN-Formula
can dilute the serum albumin concentration, causing ascites, Royal Canin Gastrointestinal High Energy
edema, diminished peripheral perfusion, or a combination Royal Canin Canine Low Fat
of these. Careful calculation of the fluid needs and ongoing
losses is therefore necessary. In animals with severe hypoal- This is a partial list for the purpose of showing examples;
it is not an all-inclusive list of such diets.
buminemia (e.g., serum albumin of 1.5 g/dL or less), it may
be desirable to increase plasma oncotic pressure. Adminis- *“Bland” refers to easily digestible diets that often contain less fat
tering plasma is not generally recommended because large and less fiber than is found in many pet foods.
volumes of plasma are needed to substantially increase
serum albumin concentration, making it very expensive.
Further, animals with severe protein-losing enteropathies BOX 28.2
(PLEs) and protein-losing nephropathies rapidly excrete the
administered protein, making repeated transfusions neces- Examples of Homemade Hypoallergenic* Diets
sary. Human albumin has been administered and appears 1 part boiled white chicken or turkey meat without the
efficacious; however, some animals can die acutely from ana- skin; 2 parts boiled or baked potato (without the skin)
phylaxis. Canine albumin (5-6 mL/kg) is safer but is not 1 part boiled or broiled white fish without the skin; 2
readily available. Hetastarch and pentastarch may be used in parts boiled or baked potato (without the skin)
place of plasma or albumin. These colloids are larger than 1 part boiled mutton, venison, or rabbit without the skin;
albumin and persist in the intravascular space longer than 2 parts boiled or baked potato (without the skin)
albumin, thereby helping maintain plasma oncotic pressure 1 part drained low-fat cottage cheese; 2 parts boiled or
in animals with severe PLE. After administering these col- baked potato (without the skin)
loids, the clinician should decrease the rate of fluid admin- A nonflavored vitamin supplement may be given three
times per week.
istration to prevent hypertension. Sometimes, administering Rice can be substituted for potato, but many dogs and
hetastarch causes fluids to shift to the extravascular compart- cats seem to digest potato more easily than rice.
ment with subsequent decrease in peripheral perfusion or
worsening of ascites. These diets are not balanced but are usually adequate
for 3 to 4 months of use in sexually mature animals. If
growing animals are being fed such a diet, then a
DIETARY MANAGEMENT nutritionist must be consulted to balance calcium and
phosphorus.
Dietary therapy is often important in animals with gastro-
intestinal tract problems. Symptomatic therapy for acute *Hypoallergenic refers to a diet specially formulated for a given
animal, one that does not expose the animal to potential allergens
problems usually involves easily digested diets (i.e., “bland”), that it has eaten in the past. Therefore the clinician must obtain a
whereas specific therapy typically involves elimination (i.e., careful dietary history to determine what will or will not constitute a
hypoallergenic) diets, ultra–low fat diets, fiber-supplemented hypoallergenic diet for a particular animal.
diets, or a combination of these.
“Bland” (i.e., easily digested) diets are low in fat and fiber resolves, and then the diet is gradually changed back to the
(both delay gastric emptying) and high in complex carbo- routine one. This diet may be continued after the event is
hydrates. Extremely hyperosmolar diets (e.g., concentrated over, but a homemade diet should be nutritionally balanced
sugar solutions or honey) should be avoided because they if it is used long term, especially in puppies or kittens.
also may delay gastric emptying. These diets are indicated in Elimination diets are indicated if a dietary allergy (i.e., an
animals with acute gastritis or enteritis. Such diets are avail- immune-mediated hypersensitivity) or intolerance (i.e., a
able commercially (Box 28.1). Homemade versions usually non–immune-mediated problem) is suspected. These diets
consist of boiled poultry or lean hamburger, low-fat cottage contain either dietary ingredients unlikely to provoke allergy
cheese, boiled rice, and/or boiled potatoes in some combina- or intolerance (i.e., hydrolyzed diets that contain relatively
tion. Boiled chicken, turkey, or fish and green beans may be small particles that are less antigenic) or food stuffs the
useful in cats. A typical mixture is one part boiled chicken or patient has not been exposed to before (i.e., a novel protein
cottage cheese and two parts boiled potato. These diets also diet). Excellent commercial elimination diets are available,
tend to be low in lactose, which helps prevent maldigestion. or the clinician may suggest a homemade diet. Examples of
Frequent, small amounts of these foods are fed until diarrhea homemade elimination diets are described in Box 28.2.