Lump on belly of gelding

Question
Hi there, I have a 22 yr. AQHA gelding who is in great shape. 4 days ago, i noticed a large lump on his belly, I went to touch it and the horse nearly took a bite out of me. the next morning, just behind 12in. behind the bump was a blood draining, so I began warm compresses to draw out the yuck. Well, I did that 2 times daily for 3 days, that is better, but the lump remains and I tried touching it tonight and I got the same reaction from him, ready to hurt me. It is probably 8-10 inches and oval in shape.  and it is only on the one side of his belly, not in the middle or on both sides. I am just wondering if I should wait and watch or take him to the vet? Otherwise, he is eating fine, not acting like it is bothering him, until I go there.  thank you for any help you can offer, much appreciated.
Sincerely, Shelley

Answer
Hi Shelley.
   Let me preface this by saying that I'm not a veterinarian, but I was gainfully employed as an RN for almost 20 years.
   From your description and your boy's reaction, it sounds to me like he has a hernia. Basically what happens with a hernia is a piece of intestine works it's way through a weak area of muscle--and at 22 years old, his muscles won't be as strong as they were at 3. While the piece of intestine is through the muscle, the blood supply is compromised, and it can be VERY painful.
   I definitely recommend a vet visit; there is a possibility that the hernia can be reduced without surgery. If surgery is needed, the latest research I've seen indicates older horses do just as well as the youngsters after abdominal surgery.
   Best of luck with your boy! PLEASE let me know how you make out.
Anne Stepien