Studies estimate that this happens once in every 5,500 to 7,000 surgeries; there were 51.4 million in-patient procedures performed in 2010, according to the National Center for Health Statistics. The authors of a new study estimate that a typical hospital has two of these incidents each year.
Not surprisingly, each mistake is costly. In 2007, the Centers for Medicare and Medicaid Services estimated the average price of removing one of these items at $63,631 per hospital stay, and larger settlements in lawsuits can run from $2 million to $5 million.
According to the new study, in the September issue of the Journal of the American College of Surgeons, the item left behind is usually a surgical sponge, those two-inch-by-two-inch or larger squares of gauze used to sop up blood. And, the authors say, technology offers a way to reduce the number of times this happens, which medical officials already are trying to limit via an awareness campaign.
Traditionally, nurses keep track of sponges by counting them before and after surgeries. But sponges can be hard to locate when they are soaked in blood and tucked away out of sight (the most common places they are left are in the abdomen, pelvis, thoracic cavity and vagina), and they are much more hospitable to bacteria than a needle or a drill bit fragment -- two other commonly retained items. Sponges are often lost during emergency surgeries, when there is little time to thoroughly count their use.
In the past, hospitals have turned to X-rays and bar codes to help detect lost material, but the study identified radiofrequency detection systems as the best and most cost-effective way to keep track of sponges. Each piece of gauze has a tiny chip sewn into a pocket and operating room personnel can use a wand or mat at the end of a procedure to detect whether a sponge is left inside. (An even newer system, which identifies each individual sponge with a similar chip, has not been used on a sufficient number of patients to be fully studied.)
A 2012 study from the University of North Carolina found that such technology helped locate 23 sponges left behind in nearly 3,000 patients over 11 months.
"We are firm supporters of adjunct technology, in addition to counting," said Julie Cerese, senior vice president of performance improvement for UHC, an association of nonprofit academic medical centers, which conducted the study. "We want to be very clear that we support counting and the use of adjunct technology to find any retained foreign bodies."
When they looked at 824 reports of sponges that remained inside surgery patients, the authors found that the majority, 525, were left intentionally by surgeons for medical reasons. Forty-one were unintentional; of those, 28 were discovered after the surgeon had closed the surgical cavity. Nine were discovered after the patient had left the operating room but was still recuperating in the hospital, and four were found after the patient was discharged.
In nearly half the cases, the surgeon continued to close the incision despite noting that before and after sponge counts did not match. Cerese said surgeons may continue closing while a recount is being conducted or because it's important to limit the time a patient is under anesthesia.
Between 2006 and 2012, the study found a 93 percent drop in the number of sponges accidentally left in patients at five hospitals that used radiofrequency technology, compared with a 77 percent decrease at places that did not have that method. The high tech method also delivered a steady decline over that time, while other methods produced inconsistent decreases year to year. They estimated that the technology would save a medical center $157,024 in operating room time and X-ray costs, along with $441,534 in medical and legal costs. In contrast, the technology would cost just $191,352 to install and use.
"The process we have used for many years, manual counting, has the potential for error. It just does," said Marilyn Szekendi, director of quality research at UHC and one of the study's authors. "...So these types of technologies just support the clinician."