Dogs with severe CPV enteritis may have a prolonged course of hospitalization and may require nutritional support to prevent
catabolism and immune dysfunction associated with negative nitrogen balance.
Partial parenteral nutrition (PPN) does not supply all of the patient's nutrient needs but can provide short term support
for animals that are expected to recover soon. The advantage of PPN solutions is that they can be delivered through a peripheral
vein rather than through a large central vein. PPN solutions are usually given at a maintenance dose (60 ml/kg/day) and additional
fluid needs are met with crystalloid solutions as described earlier. Procalamine (McGaw, Inc.) is a commercial product which
contains 3% amino acids, 3% glycerol, and electrolytes. A "homemade" PPN solution can be made by adding 300 ml of 8.5% amino
acid solution (Travenol, Baxter, Inc.) to 700 ml lactated Ringer's solution with 5% dextrose. The addition of lipid emulsions
is controversial. Although lipids are rich in caloric content, they have been associated with immunosuppression through impairment
of reticuloendothelial function and reduction in white blood cell phagocytosis.
A common complication of PPN solutions is catheter phlebitis because the solutions are hypertonic. Catheters must be placed
aseptically and the site monitored carefully for redness, swelling or pain. Solutions containing dextrose should be tapered
off gradually to prevent rebound hypoglycemia.
Most practitioners offer water after vomiting has been absent for 12 - 24 hours. Early enteral nutrition is important to
promote intestinal regeneration. A liquid diet (Clinicare) can be offered initially, or a gruel can be made with an easily
digestible high carbohydrate, low fat diet. The addition of glutamine powder (0.5 g/kg divided q 12 hours) to drinking water
may promote GI healing in dogs recovering from CPV enteritis. Various veterinary recovery diets are available for post hospital
care. The puppy may have temporary intestinal malabsorption and protein-losing enteropathy until intestinal villi are repaired.
Initial feeding should consist of small amounts of an easily digestible low fat diet fed frequently. The normal diet is gradually
re-introduced after appetite and stool have returned to normal. Following recovery, immunity to parvo virus infection lasts
at least 2 years, and may even be lifelong.