Generic Drug Name: Hetastarch
Other Common Names: Hespan, Hextend
Hetastarch is a volume expander that is used to treat hypovolemia when colloidal therapy is required. It is primarily used when crystalloid therapy has negative effects on the patient and HES colloid therapy is more beneficial. Hetastarch has been found to be beneficial in increasing plasma oncotic pressure and volume expansion in hypoproteinemic conditions, as well as reducing endotoxin-induced vascular permeability in horses.
Hetastarch has been known to cause significant bleeding in animals with compromised coagulation systems. It should be used cautiously in patients with thrombocytopenia and those undergoing CNS surgery. Hetastarch may have negative effects on patients with liver disease, as it can affect indirect serum bilirubin levels. Negative effects may also occur in patients with renal dysfunction, congestive heart failure or pulmonary edema, sepsis, systemic inflammatory response syndrome, or severe trauma.
Hetastarch can affect platelet function and coagulation times, as well as cause changes in clotting times and platelet counts due to direct and dilutional causes. Animals with preexisting coagulopathies may be more susceptible to further bleeding. Hetastarch can cause sensitivity reactions and interfere with antigen-antibody testing. When given as a rapid infusion in cats, signs of nausea and vomiting may occur. Hetastarch can possibly cause circulatory overload, leading to pulmonary edema. It should also not be given intramuscularly, as bleeding, bruising, or hematomas may occur.
Hetastarch should not be used in animals with a known allergy or hypersensitivity to the drug. A veterinarian should be contacted immediately if an overdose is suspected.
Hetastarch should be kept at room temperature in a tight, light resistant, childproof container. It should be kept away from conditions that may cause freezing. If the drug turns a deep brown color or formation of a crystalline precipitate occurs, it should not be used.
Hetastarch should be administered as frequently as the patient requires it. This can be determined by blood volume, indication, and patient response. A typical dose in dogs and cats is anywhere from 1-2 mL/kg an hour, or 5-20 mL/kg as necessary. A typical dose in horses is 3-10 mL/kg/day. In the case of a dose being forgotten, it should be administered as soon as possible. If it is almost time for the next scheduled dose, the missed dose should be skipped and the regular schedule should be resumed. Two doses should never be administered at the same time.
Doses may vary in different species, when the drug is given by a different route or concurrently with other medications, and with regards to a patient's age, breed, and health status. A veterinarian's dosing instructions and/or those printed on the medication label should be followed closely.