title: Effects of 5% and 10% guaifenesin infusion on equine vascular endothelium.
abstract: Twelve horses of various breeds and either sex were anesthetized with xylazine and ketamine injected into a median or lateral thoracic vein. During anesthesia, with the horse in sternal recumbency, a 14-gauge, 8.9 cm catheter was inserted into each jugular vein by using aseptic technique. Guaifenesin in water (100 mg/kg or a maximum dose of 50 grams) was infused into one jugular vein and an equal volume of 0.9% saline solution was infused into the other jugular vein. Seven horses received 10% guaifenesin, and five horses received 5% guaifenesin. The catheters were removed before the horses recovered from anesthesia. The horses were euthanatized approximately 48 hours later, and the jugular veins were removed for histologic examination. Adherent thrombus material was observed in all veins exposed to 10% guaifenesin and in one vein exposed to 5% guaifenesin. No evidence of thrombus was observed in four veins infused with 5% guaifenesin or in those infused with saline solution. These findings are of particular significance with horses at increased risk for thrombosis or thrombophlebitis.
authors.affiliation: Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens.
authors.forename: M A
authors.initials: MA
authors.lastname: Herschl
authors.forename: C M
authors.initials: CM
authors.lastname: Trim
authors.forename: E A
authors.initials: EA
authors.lastname: Mahaffey
mesh_terms: D000818:Animals; D004730:Endothelium, Vascular / Q000187:drug effects*; D005260:Female; D006140:Guaifenesin / Q000008:administration & dosage / Q000009:adverse effects*; D006734:Horse Diseases / Q000139:chemically induced; D006736:Horses / Q000502:physiology*; D007262:Infusions, Intravenous / Q000662:veterinary; D007601:Jugular Veins / Q000187:drug effects; D008297:Male; D013927:Thrombosis / Q000139:chemically induced / Q000662:veterinary
chemical_list: D006140:Guaifenesin