Electronic tagging of surgical sponges to prevent their accidental retention

The inadvertent "loss" of surgical sponges, towels, and instruments remains an unsolved problem. The means of preventing this mishap involve an inventory of all implements going in and coming out of the surgical wound, supplemented by a careful search. This work describes a different approach to this problem: tagging articles placed into the wound with markers able to be rapidly detected electronically.

Surgical sponges were tagged with either active targets or inert, dummy targets and placed in different locations within the body of 50 cadavers. Using a device we constructed, blinded readings were performed to test the accuracy of detecting retained sponges.

A total of 600 readings were made in 50 cadavers, 300 of active targets and 300 of inert, dummy targets, indistinguishable in appearance. The active markers were detected with 100% accuracy. There were no false positive detections of the dummy tags.

The present work demonstrates the feasibility of detecting retained surgical sponges by electronic means blinded to whether the tag contained an active or inert marker.