Police say Judy Phillips suffered severe bites on her arm and leg.
When medics arrived, they found her on the driveway of the house, drifting in and out of consciousness as a result of her injuries.
Meanwhile, the pit bull had gone inside the home, where another woman had locked herself and a young child in a bedroom. Police helped them escape out a window.
Benton County Animal Control captured the dog in a back bedroom of the home and is now holding it in quarantine. The owner of the dog is under investigation for harboring a dangerous animal.
Phillips was reported in satisfactory condition by Sunday afternoon at Kadlec Regional Medical Center in Richland.