Canine parvovirus (CPV) is a serious and potentially fatal viral illness that remains common in dogs, despite the availability and efficacy of vaccinations. Without treatment, parvoviral enteritis has a mortality rate in excess of 90%. Hospitalization and aggressive care can decrease mortality to 10-30%; however, this approach is often cost prohibitive. In this article, we will review an outpatient protocol for dogs with parvoviral enteritis.
There has been recent investigation into the efficacy and safety of providing outpatient care to patients whose owners cannot afford inpatient treatment. Venn et al. established a protocol for outpatient care at Colorado State University that demonstrated 80% survival in outpatients compared to 90% survival for inpatients.
Guidelines for Outpatient Treatment of Canine Parvoviral Enteritis
In preparing an outpatient protocol for CPV patients, understanding the indications and limitations is essential.
Hospitalization is the gold standard recommendation for all patients with CPV, however, for financially-constrained Clients, outpatient care can be considered. Only patients mildly to moderately affected should be considered candidates for outpatient care. Any patient with severe dehydration, evidence of shock, or an obtunded mentation should be hospitalized. If hospitalization is not feasible, humane euthanasia should be considered. For those mildly affected, an outpatient protocol can be attempted if the client is amenable to a significant time commitment and comfortable administering subcutaneous injections.
- Fluid therapy. Isotonic crystalloids should be administered subcutaneously at a dose of 40ml/kg every 8 hours to provide maintenance fluid and account for ongoing losses. Over the first 24 hours, dehydration should be corrected by administering the calculated fluid deficit in addition to maintenance fluids.
- Antibiotics. Though CPV is a viral disease, antibiotics providing gram negative and anaerobic coverage are recommended to treat bacteremia resulting from translocation of bacteria across the damaged intestinal epithelium. Appropriate antibiotic coverage can be accomplished by using amoxicillin-clavulanate, combination therapy with a fluoroquinolone and metronidazole. However, given the intolerance of oral antibiotics in nauseous animals, cefovecin was used in the referenced outpatient protocol due to its convenience and reasonable coverage against anaerobes and gram-negative bacteria.
- Anti-emetics. Subcutaneous administration of anti-emetics, such as maropitant and ondansetron, will aid in prevention of vomiting.
- Pain management. If the patient is painful, subcutaneous buprenorphine can be considered.
- Glucose and potassium supplements. Glucose and potassium supplementation should be considered in the form of oral corn syrup and Tumil-K, respectively.
- Dietary management. Food and water should be withheld until vomiting has ceased for at least 6 -12 hours. Calorie dense food, such as Hill’s a/d, should then be syringe fed at a dose of 1ml/kg every 6 hours.
Importantly, Venn et al’s protocol for outpatient care was only initiated after the Patients were administered a fluid bolus to restore intravascular volume and treated for hypoglycemia and electrolyte derangements. Patients receiving outpatient care also returned to the veterinarian once daily for evaluation. Any patient experiencing persistent diarrhea and/or vomiting, developing a fever >104◦F, or declining in mentation was transitioned to inpatient care. Thus, this protocol is more conservative than many inpatient protocols, but is not entirely an “outpatient” protocol and yet requires significant dedication and modest financial commitment on the client’s part.
Consider Outpatient Treatment of Canine Parvoviral Enteritis with Care
Outpatient care can be considered for a select group of Patients, but it must be clearly offered to the client as an inferior option. In addition to educating clients about the care regimen, it is essential that they know what symptoms indicate outpatient care is inadequate. With ever expanding options for care, the number of CPV survivors will hopefully increase over time, but it must be remembered that although outpatient care is an option, it is not a panacea for all patients with parvoviral enteritis.