Imagine that you go into the doctor's office one day and they inform you that you have a condition that, although not very serious, warrants surgery to correct. In your mind, you may be a little worried. But you also know that most of the time these surgeries go off without a hitch. So you and your doctor discuss some times and eventually you agree on a date for your surgery.
That day comes around and you're feeling okay going into surgery. You're a little nervous, and yet confident you will come out of the surgery just fine. After a few hours under the influence of anesthesia, you wake up and your doctor tells you that everything went very well and that you should feel fine in no time.
As reassuring as this is, you start feeling intense pain near the site of the surgery 24 hours later, and this only gets worse as the hours pass. Doctors and surgeons have no idea what could be causing this pain. Eventually it gets so bad that they have to go back in and perform a second surgery -- and guess what they find? A surgical sponge was left inside of you.
It may seem impossible, but "retained surgical items" do happen, albeit rarely. Roughly one out of every 5,500-7,000 surgeries end with the patient retaining one of these surgical items. They cause severe complications, and can even result in fatal complications. Obviously, this is negligence and the hospital and/or medical staff members handling your surgery should be held responsible for their poor treatment.
Source: Washington Post, "When your surgeon accidentally leaves something inside of you," Lenny Bernstein, Sept. 4, 2014