Hi I'm Rosie one of the vets and I'd like to try and help you. I'm so sorry that this happened. I used to run an emergency clinic and unfortunately saw a lot of dogs with internal bleeding. Some we could save, some we couldn't. When the liver bleeds, it really bleeds, and you can lose them in minutes.
Generally speaking liver tears have one of four causes. The first is blunt trauma. This is where the patient gets hit really hard by something without damaging the skin or causing any internal injuries, but enough to cause internal injuries. The most common time we see this is pets (dogs/cats) that have been hit by a car, as it really takes quite a lot of force. Occasionally we see it in cats that have fallen out of trees, or dogs that have fallen out of windows. The most common injury with this type of trauma is either a ruptured (torn) liver or spleen.
The second is sharp or penetrating trauma. This is exactly as it sounds - those patients who have an external injury to the abdomen which has made a hole in the liver and caused a problem. This is usually cats, as they tend to be in that situation - for example falling onto fences or getting bitten by dogs. It can happen to small dogs, when a larger dog attacks them, and I have seen it in greyhounds when they just run so fast they run into objects before realising the object is there.
The third, and what I suspect happened in your case, is an underlying tumour. The most common is a tumour of the blood vessels inside the liver. This weakens the wall of the blood vessels itself and causes almost like a bubble to appear. Eventually, the bubble bursts, and the patient loses a lot of blood very quickly.
The fourth is a congenital issue. This is where somewhere in the development the liver wasn't formed correctly, or a blood vessel inside the liver wasn't formed correctly. This is where the liver is going to tear at some point and there really isn't much that anybody can do about it, apart from trying to treat it when it happens.
Whether these patients survive depends purely on how fast they can be brought to clinic and how big the tear is. Generally, those with splenic injuries (injuries to the spleen) usually can be saved, but it is very rare indeed that we manage to save a patient with a severe liver tear as the bleeding is just too fast.
I hope I've helped, and again I'm sorry that this happened. If you have any questions from this or need clarification on anything then just get back to me. Otherwise, if you have found this useful, please leave a positive rating so that I may be compensated for my time. Thank you, ***** ***** the best, Rosie.