Prevention of retained surgical sponges: a decision-analytic model predicting relative cost-effectiveness.
BACKGROUND
New technologies are available to reduce or prevent retained surgical sponges (RSS), but their relative cost effectiveness are unknown. We developed an empirically calibrated decision-analytic model comparing standard counting against alternative strategies: universal or selective x-ray, bar-coded sponges (BCS), and radiofrequency-tagged (RF) sponges.


METHODS
Key model parameters were obtained from field observations during a randomized-controlled BCS trial (n = 298), an observational study of RSS (n = 191,168), and clinical experience with BCS (n approximately 60,000). Because no comparable data exist for RF, we modeled its performance under 2 alternative assumptions. Only incremental sponge-tracking costs, excluding those common to all strategies, were considered. Main outcomes were RSS incidence and cost-effectiveness ratios for each strategy, from the institutional decision maker's perspective.


RESULTS
Standard counting detects 82% of RSS. Bar coding prevents > or =97.5% for an additional $95,000 per RSS averted. If RF were as effective as bar coding, it would cost $720,000 per additional RSS averted (versus standard counting). Universal and selective x-rays for high-risk operations are more costly, but less effective than BCS-$1.1 to 1.4 million per RSS event prevented. In sensitivity analyses, results were robust over the plausible range of effectiveness assumptions, but sensitive to cost.


CONCLUSIONS
Using currently available data, this analysis provides a useful model for comparing the relative cost effectiveness of existing sponge-tracking strategies. Selecting the best method for an institution depends on its priorities: ease of use, cost reduction, or ensuring RSS are truly "never events." Given medical and liability costs of >$200,000 per incident, novel technologies can substantially reduce the incidence of RSS at an acceptable cost.
Department of Health Policy and Management, Harvard School of Public Health, Boston, MA, USA. sregenbogen@partners.org
Scott E
SE
Regenbogen
Caprice C
CC
Greenberg
Stephen C
SC
Resch
Anantha
A
Kollengode
Robert R
RR
Cima
Michael J
MJ
Zinner
Atul A
AA
Gawande
D003287:Contrast Media; D003362:Cost-Benefit Analysis; D003661:Decision Support Techniques; D005547:Foreign Bodies / Q000191:economics* / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D015994:Incidence; D007431:Intraoperative Complications; D007553:Isotope Labeling; D018803:Models, Economic; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D015503:Surgical Sponges / Q000009:adverse effects* / Q000191:economics*
D003287:Contrast Media