Treatment of severe parvoviral enteritis (Proceedings) - Veterinary Healthcare
  • SEARCH:

ADVERTISEMENT

Treatment of severe parvoviral enteritis (Proceedings)


CVC IN KANSAS CITY PROCEEDINGS


Systemic Antibiotics

Hemorrhagic diarrhea and mucosal sloughing are commonly seen in dogs with CPV enteritis, and indicate breakdown of the GI mucosal barrier which can lead to bacterial translocation, endotoxemia, and sepsis. Severe neutropenia often coincides with the severe enteritis contributing to the risk of systemic sepsis. For these reasons, intravenous broad-spectrum, bacteriocidal antibiotics are indicated in severely affected puppies. A combination of an aminoglycoside (gentamicin 2.2 mg/kg q 8 h or amikacin 10 mg/kg q 8 h) with a beta lactam antibiotic (ampicillin 22 mg/kg q 8 h or cefazolin 22 mg/kg q 8 h) provides excellent coverage against gram negative and anaerobic bacteria which may originate from the gut. Aminoglycosides can cause acute renal failure and should only be administered after rehydration has been accomplished. Once daily dosing of aminoglycosides (6.6 mg/kg gentamicin or 30 mg/kg amikacin q 24) may minimize renal damage while maximizing bacterial kill because of high peak and low trough antibiotic concentrations, but the high dose should never be given to dehydrated patients. Urine sediment should be monitored for the appearance of proteinuria or renal tubular casts, which would warrant discontinuation of aminoglycoside therapy. Enrofloxacin (5 mg/kg q 12 h) is an alternative choice to the aminoglycosides. It has an excellent gram negative spectrum, but is not approved for intravenous use and may cause cartilage abnormalities in young growing animals. The author has not encountered any problems with enrofloxacin when it is diluted 1:1 with saline and administered slowly IV for a relatively short term (usually 3 - 5 days) in puppies with CPV enteritis. Rapid administration may cause vomiting. The drug can be discontinued when leukopenia resolves.

Mildly affected dogs with an adequate white blood cell count generally do not require combination antibiotic therapy. Appropriate antibiotic choices include ampicillin, cephalosporins, or trimethoprim-sulfa in these patients.

Anti-Emetics

Vomiting often decreases when oral intake of food and fluid is discontinued, but in some patients the problem persists and must be treated to reduce fluid losses and increase patient comfort.

The two antiemetics most commonly used in dogs with CPV enteritis are metoclopramide and chlorpromazine. Metoclopramide is a gastric promotility drug which can reduce vomiting by stimulating gastric emptying and inhibiting the chemoreceptor trigger zone. The promotility effect may prevent gastric atony and ileus from occurring in dogs with CPV. Metoclopramide can be added to the intravenous fluids or administered in a separate drip at a dosage of 1.0 - 2.0 mg/kg/24 hours and given as a constant rate infusion.

If metoclopramide is ineffective in controlling vomiting, a more effective antiemetic is chlorpromazine. This drug is a phenothiazine derivative and acts on the emetic center, the chemoreceptor trigger zone, and peripheral receptors to reduce the vomiting reflex. The recommended dosage is 0.1 mg/kg IV q 4-6 h or 0.2 - 0.5 mg/kg IM q 6 - 8 h as needed. Phenothiazine derivatives can cause hypotension and systemic vasodilation via their alpha adrenergic blocking effect and should only be given after the patient is well hydrated.


ADVERTISEMENT

Source: CVC IN KANSAS CITY PROCEEDINGS,
Click here