Open appendectomy is the traditional method and the standard treatment for appendicitis. The surgeon makes an incision in the lower right abdomen, pulls the appendix through the incision, ties it off at its base, and removes it. Care is taken to avoid spilling purulent material (pus) from the appendix while it is being removed. The incision is then sutured.
If the appendix has perforated (ruptured), the surgeon cleans the pus out of the abdomen with a warm saline solution to reduce the risk for infection. A drain may be inserted through the incision to allow the pus to drain from the abdomen. In this case, the skin is not sutured, but left open and packed with sterile gauze. The gauze and drain remain in place until the pus is completely drained and there is no sign of infection.
If the abdomen is so inflamed that the surgeon cannot see the appendix, the infection is drained and treated with antibiotics, and then the appendix is removed.