Surgical sponges embedded with a radiofrequency chip were identified 100% of the time, an accuracy rate far better than traditional counting or use of radiographs during surgery, according to a study at the Veteran's Affairs Medical Center in Iowa City.
The blinded clinical trial, funded by the VA, entailed the placement of 840 sponges, 619 of which had the RF chip and 221 of which did not, in opaque bags. The bags were attached to 210 participants' at the back of the torso and in each of four abdominal quadrants. Of the 210 participants, 101 were morbidly obese, a risk factor that has much higher rates of retained surgical sponges and other forgotten devices.
After the sponges were attached to the participants' torsos, the participants were asked to lie in a supine position on an exam table while operators blinded to the bags' contents waved a special RF wand, attached to a detection console made by RF Surgical Systems, over the participants.
As the wand passed that portion of the participant's torso with the sponge, the console relayed a sound with 100% accuracy indicating the presence of a tagged sponge. It was quiet, with 100% accuracy, when the wand passed over a sponge that did not have an RF chip.
The RF tagging system was far more accurate than taking X-rays before a patient is wheeled into recovery, and was more accurate than traditional practice of counting, wrote the study's principal investigator, Victoria Steelman, a member of the Board of Directors of Association of Perioperative Registered Nurses. "Studies have found that 62% and 88% of retained surgical items occurred when the count was reported as correct."
Steelman said her report is "the first systematic evaluation of RF sponge detection technology in a sample size powered to determine its sensitivity and specificity."