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.
Regenbogen
Scott E
SE
Department of Health Policy and Management, Harvard School of Public Health, Boston, MA, USA. sregenbogen@partners.org
Greenberg
Caprice C
CC
Resch
Stephen C
SC
Kollengode
Anantha
A
Cima
Robert R
RR
Zinner
Michael J
MJ
Gawande
Atul A
AA
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