Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose

Jugular Vein Thrombosis

Synonyms: Thrombophlebitis


The jugular vein is the most frequent site of intravenous injection and catheter placement in the horse.

The most common cause of clotting of the jugular vein is irritation and clot formation from an intravenous catheter. Horses that are very systemically ill are much more likely to have this complication. It is especially common in horses that have intestinal inflammation (colitis and enteritis). Horses that are very ill post-colic surgery are also at higher risk for this problem.

Horses can live a normal life with only one jugular vein. Most even survive loss of both jugulars. The jugular vein is the main avenue for return of blood to the heart from the head. When a horse loses its jugular vein, the head swells transiently because of back pressure in the vessels from the "damming effect" of the clot. Horses that lose both jugular veins may have chronically swollen heads.

my vet's role


The prognosis for life is generally good with loss of a jugular vein. However, this condition tends to accompany other life-threatening conditions. It can be one more complication leading to a poor outcome in horses undergoing intensive care for a variety of causes. Loss of jugular veins complicates ongoing intensive care and requires the use of other, harder to maintain veins for intravenous fluid and medication administration.

Author: Doug Thal DVM Dipl. ABVP