Aggressive fluid resuscitation is part of the treatment for distributive shock. Distributive shock is where blood flow is moved away from the central circulation due to peripheral vasodilation. If the animal is still experiencing hypotension after fluid replacement, vasopressors can be used to support overall function and increase blood pressure. Dopamine, norepinephrine, dobutamine, and vasopressin are agents used as a continuous rate infusion and are gradually reduced once blood pressure is stable.3
Norepinephrine has the quickest onset of action of within 1 to 2 minutes but persists for only 1 to 2 minutes. Dopamine has the longest onset of action of within 5 minutes but persists for <10 minutes after infusion has stopped. Vasopressin peaks within 15 minutes of continuous infusion.
With all agents, monitor blood pressure, heart rate, and an ECG. Digoxin is recommended before dobutamine administration to slow AV nodal conduction. Dopamine and norepinephrine are protected from light, and all are stable 24 hours room temperature. Vasopressin is stable for 18 hours room temperature or 24 hours refrigerated. Dobutamine does not have an indication for shock but has been shown to be helpful. Norepinephrine is first line and adjunctive agents can be added: dopamine, dobutamine, or vasopressin, depending on species.
- Dobutamine. Plumb’s™. https://academic.plumbs.com/
- Dopamine. Plumb’s™. https://academic.plumbs.com/
- Linklater A. Fluid therapy in animals – emergency medicine and critical care. Merck Veterinary Manual. https://www.merckvetmanual.com/emergency-medicine-and-critical-care/fluid-therapy/fluid-therapy-in-animals. Published January 31, 2023.
- Norepinephrine . Plumb’s™. https://academic.plumbs.com/.
- Vasopressin. Lexicomp. https://online.lexi.com/.
- Vasopressin. Plumb’s™. https://academic.plumbs.com/
*All references accessed February 21, 2023
By Kylie Kelly, PharmD, FSVHP
Dr. Kelly is the 2023-2024 Wasson Clinical Veterinary Pharmacy Resident at Purdue University Teaching Hospital.