How Can Severe Pain In The Legs Be Treated?

My sister was Dx with DVT in her leg, she had a filter put in because unable to take blood thinners due just getting bleeding from a polyp stopped they found bleeding after two colonoscopy done within a week I which they cut. She had 10 units of blood given during this timeframe, so naturally blood thinners are not an option. Now she is having extreme Spain in her leg where the clot is and they share hoping it will dissolve on its own. I don t think so, her leg is swelling daily and she s unstable to move her leg and can t walk. My question is what other procedure can be done to relieve the pressure, she s in such pain sand wishes to die. Could compression socks help dissolve or relieve some pain or should surgery, or some sort of injection at the clot site help dissolve it without blood thinners. She has no kids or husband sand I m desperate to help her survive this health matter. Thank you,