Skip Navigation

Horse Anesthesia

For our last anesthesia lab before beginning the surgery section of the course, our professors demonstrated how to perform field anesthesia on a horse.  When anesthetizing a horse (or really doing anything with a horse), there's one thing you should really keep in mind: horses are BIG.  That means they are a danger to not only the veterinary staff but to themselves.  That means they need a lot of drug to get them to sleep.  And it also means that when they go down, they can go down hard.

So with that in mind, I was pretty excited and nervous to watch this demonstration.  For the reasons I just mentioned, horse anesthesia can be pretty nerve-wracking.  But this demonstration had a little extra layer to cause anxiety.  This was to be field anesthesia, meaning the procedure was literally performed in a field.  No walls, no roof, not even a fence.  Just grass and the open sky.  And fifty vet students grouped around to watch.  Now at first thought, this seems pretty, um, insane.  Especially to me, who has little experience with horses.  But guess what?  Sometimes you don't get the luxury of a clinic or an operating room.  If a vet is making a house call or there's an emergency, a field may be the best she's got. 

Being part Irish and after years of experience with Murphy's Law, I expected the worst.  So I was completely blown away with how smooth and choreographed it unfolded.  As we watched, Dr. Lepiz injected a sedative (xylazine, in case you're interested) into the intravenous catheter already placed in the jugular vein.  Over the course of five minutes, the horse's head slowly dropped lower... and lower… and lower… until her head reached her knees.  As we learned in class, "Head to knees, ketamine please" so Dr. Lepiz then injected ketamine, the induction agent (or the drug that actually results in the unconsciousness of the horse).  This was the most impressive part: as the horse began to lose consciousness, one person pushed on the neck and shoulders while Dr. Lepiz pulled on the tail until the horse was sitting like a dog.  Then, she simply and slowly dropped to one side and was out in the grass. 

For the next ten to fifteen minutes, we crowded around to watch a fellow student insert an endotracheal tube, we listened to our professors answer questions and we took turns feeling the pulse and listening to the heart.  Then, as the drugs began wearing off, the endotracheal tube was removed, and the horse sat up and was up on her feet like nothing had really happened.  And it was over.