KUOW in Seattle reports that about 30 times per year, a sponge or surgical instrument is left inside a patient at a hospital in Washington state. Foreign ojects left behind are among the state's most common medical mistakes. Medical experts told KUOW such an event should never happen, at that the system in place to check for sponges and other equipment left behind is not straightforward. New technology exists to ensure such equipment is not left behind, but it is not widely used.
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