Pa Patient Saf Advis 2010 Dec;7(4):154.   
Letter to the Editor: Marking the Nonoperative Site
Anesthesiology, Nursing, Surgery
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I’m writing to ask for the Pennsylvania Patient Safety Authority’s assistance and guidance on an issue related to our ongoing efforts to eliminate wrong-site or wrong-side surgery. We’re having an internal discussion within our organization as to the value or danger of marking the nonoperative site or side in addition to marking the operative site. As you know, all the literature rightly indicates that we should clearly and unambiguously mark the operative site. There are some in our organization who feel it increases safety to also mark the nonoperative side with something like “Not this side.” There are others who feel that this decreases safety in that marking a nonoperative site or side will eventually lead to a procedure being done on the wrong side by virtue of misinterpretation of the mark at that site. We’d be very interested in any guidance or information you or any of your readers can supply.

Gary A. Merica, RPh
Quality Manager for Pharmacy Services and Medication Safety Coordinator
York Hospital

Editor’s Note

The Pennsylvania Patient Safety Authority’s database contains no records of either someone doing wrong-site surgery because of a “No” mark or of someone avoiding wrong-site surgery because of a “No” mark, so the Authority’s opinion is based on theory. The purpose of the mark is to maintain proper orientation in the operating room. At a theoretical level, a “Not this side” mark could lead to two errors, one of which has been reported to the Authority. The first problem, which the Authority’s analysts have seen instigated by a variety of cues, is confirmation bias. The team could see the mark, without reading it properly or entirely, and be misled into thinking that it was the operative mark. This could be especially true if it was not standard practice throughout the hospital. The second problem is that the mark is referenced in the prepped and draped field, so that a partially visible mark, “this side,” might be interpreted as the correct-side surgical site mark. If the surgeon is adamant about marking the nonoperative side, the Authority’s analysts strongly suggest doing it in such a way that it could not possibly be confused with the site mark even by someone who could not read English. For example, the surgeon could use a large red-dot sticker or a large Band-Aid® on which he or she wrote “NO.”


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