Infection after appendix burst

had operation for apenndix burst and removed 9 inches of intestines that were deseased. the surgury was april 11 now over a month going slow and had to have acut put in the scare or wound area for drainage due to infection ,one week now on anti biotics to help infection and still have puss and blood draining??? what now still have slight swelling in area where drainage is coming from and antibiotics are done today whats next to clear up infection ???stronger anti biotics or another cut in area where swelling is ??? can you give advice ,no pain just a slight low grade fever ???