thick mucus

i have had emphysema for a while with just a small  breathing problem , don't get me wrong i could not run a mile but had no trouble doing my job as a truck driver.  i injured my shoulder in july put on light duty and did not do much physical activity after that. oct 12 had shoulder surgery, came home and laid around alot. two weeks later i go to the doctor for congestion in lung and hard time breathing. says bronchitis puts me on medicine.does not help. went to hospitol, bronchitis plus bull lung. put on  same medicine, have been to the doctor a few times he put me on steroids and breathing treatments but can't shake the thick mucus problem some times i can't take a big breath because of the mucus is so thick i can't bring it up without mucenex and steam, when i do clear it out  i breath fine but it keeps coming back  i did not have this problem before surgery.  are there any suggestions that might help