Monday, January 3, 2011

COW: Strangulating Lipoma

It has been a while since I posted a case of the week (maybe at the rate I’m going it should be case of the month—but then the acronym COM just isn’t as nice as COW). This was an older horse I saw on emergency last week. The history was a sudden onset (less than 2 hrs) very severe colic. In fact when I arrived, the horse was down, in shock and unable to get up. With the assistance of lots of good drugs we were able to get the horse comfortable enough to stand just long enough to do a rectal exam. Rectal exams are probably the single best diagnostic aid we have in sorting out colic’s. On rectal, a very tight band could be felt. This almost always means that something is twisted or displaced.

As it turned out, the cause of this horse’s colic was what is called a strangulating lipoma. They are called that because it is a lipoma that ‘strangles’ off a portion of the intestine. Lipomas are benign tumors of fat. In horses, they tend to form in a very thin membrane, referred to as the mesentery. Lipomas really do not cause a significant problem for the horse until they somehow get wrapped around a loop of intestine- almost always the small intestine. Once they wrap around a loop of intestine, the horse VERY quickly becomes extremely painful. The only way to fix the problem is surgery. Often they wrap tight enough around the intestines that they also occlude the blood flow to that section of intestine. If the circulation to the affected loops is significantly compromised then the intestine quickly begins to die, in which case at surgery the strangulated loop of intestine would have to be surgically removed. That is why, if surgery is to going to be pursued, it needs to happen ASAP. Even if surgery is elected for, sometimes you just cannot get the horse on the surgery table fast enough to save the intestine. On average about half of horses treated surgically survive in the long term.

Strangulating lipomas are so devastating, in large part, because they strike out of nowhere. There is nothing that can be done to prevent them and the only effective treatment is surgery. It is virtually impossible to detect these tumors until they cause a strangulation. The only thing that may lessen the development of these benign fat tumors is to keep your horse from getting too fat. Because it takes quite a bit of time for these tumors to form, they usually do not develop to a sufficient size to cause a problem until the horse is in its late teens or twenties. For reasons we do not yet fully understand, geldings and ponies tend to be at a greater risk for developing lipomas. The only effective treatment for a strangulating lipoma is surgery. Current estimates for an uncomplicated surgical colic are in the $5-7000 range. This type of colic is at a higher risk for post-surgical complications, so they can easily cost in excess of $7,000 to fix.

Here are the life lessons from this case: 1. With any severe, sudden onset colic, a veterinarian should be consulted immediately. In these cases, banamine is rarely ever powerful enough to suppress the severe level of pain. 2. Keep banamine on hand. Banamine is a medication that is quite effective in suppressing pain originating from the abdomen. Often a mild colic can be managed with this medication alone. If the pain does not resolve within 45-60 minutes of an oral dose of banamine, then a veterinarian should definitely be consulted. 3. Surgical costs are expensive and are almost always unexpected. It is wise to have some funds set aside in an emergency fund or have colic insurance. 4. Lipomas are just one more reason to add to the long list of reasons to keep your horse from getting overweight. Even if you do, as in this case, strangulating lipomas can and do still occur.

Here are some pictures of what they actually look like. The picture below is of the lipoma (after being unwrapped from the small intestine). Also notice the congested blood vessels to the small intestine as a result of the lipoma inhibiting the normal flow of blood.

Here is a picture of the distended loops of small intestine that develop as a result of the inability for ingesta to move through.


  1. Wow what a great post :) Thanks for sharing! I want to go to school next fall to become a vet but I was wondering, which part of the first picture shows the blood clot?

  2. Slbaldwin,
    In the second picture up from the bottom, near the top center you can see bruising and congestion of the blood vessels that supplied the affected area of the small intestine. It appears more as 'bruising' in the messentery then what you might think of as a frank blood clot. Hope that helps.

  3. Oh okay I think I see it. Thanks :)

  4. Sadly, this horse did not survive.

  5. Thank you for this post! I lost my 20 year old Gelding very suddenly on 12/1/11. At 10 to 4 pm, I went out to feed, he went to put his head down to eat, and immediately dropped and rolled. He rolled and rolled and rolled....I of course went and called the vet immediately. He got there at 4:40 pm. By 5:15pm he was euthanizing him! It was so quick, and absolutely NO WARNING what so ever! This is very likely what happened to him. Never heard of this till now.

  6. Thank you for your post. Same thing for us as above, but we lived near WSU Vet Hospital so we brought him there, on Xmas eve, and couldn't afford the surgery, so we put him down there. The docs asked if they do an autopsy for teaching, we said yes, and the strangulating lipoma was the cause. They said there wasn't anything we could have done differently, but it's nice to read this for sure.

  7. I lost Paco my 9 year old Rocky Mtn gelding on 11-11-13 suddenly due to this tumor. He had never been sick before. A real healthy horse. We found him down in his stall colic;king at 4:30 am. Our vet examined him and did a tubing procedure. His vital signs were not good. She recommended Paco be taken to Michigan State University Large Animal Clinic. They examined thoroughly examined him and did another tubing procedure. His pain level and vital signs did not improve. We decided on surgery. They found a 12 ft. section of his intestine was dead because of this tumor which had wrapped around the intestine and stopped the blood flow. In addition they found that toxic bacteria from the dead intestine was now in his system. The vet said The dead intestine could be removed but Paco would be a very sick horse due to the toxic bacteria now in his system. His chance of survival was 25%. I decide that I didn't want Paco to suffer anymore. He was put down at 2:00 pm. What a shock to me and my family. Within a 10 hour period PACO went from being a healthy horse to no longer being with us. To this day I'm still having trouble accepting the fact that Paco is gone. It happened so fast. Paco will always be in my heart.