Why is it that when the subject of specimen misidentification comes up, blood and urine often steal the spotlight? Sure, they have quantity on their side, but specimen-labeling errors aren't unknown in anatomic pathology, either. Furthermore, as Jonathan Epstein, MD, points out, when a specimen identification error is discovered, "you can always draw some more blood; it's not so easy to go back and re-biopsy somebody's brain or breast." Dr. Epstein is professor of pathology, urology, and oncology at Johns Hopkins Medical Institutions, Baltimore.
In a recent study, "Surgical Specimen Identification
Errors: A New Measure of Quality in Surgical Care" (Makary MA, Epstein
J, et al. Surgery.
2007;141:450-455), Dr. Epstein and some of his colleagues at Johns
Hopkins sought to find out just how many of those errors were being made
in their institution. The team chose to focus on the preanalytical phase
of testing because its error rate has been studied less than the analytical
and postanalytical phases, and because, as they write, it "…may represent
a significant and highly variable source of harm, given the paucity of
checks and balances routinely used for this phase and the differences
in local practices regarding specimen handling, labeling, and transport."
Over a six-month period, the authors studied how frequently
surgical specimen-labeling errors were made in the OR and outpatient clinic,
and the nature of those errors. For the purposes of the study, "identification
error" was defined as any incongruity between the specimen requisition
form and the corresponding labeled specimen the laboratory received. That
included specimens labeled with the wrong laterality, tissue site, or
patient name; specimens missing a patient name or tissue site; specimens
with no label at all; and containers in which there were no specimens.
The most common errors, they discovered, consisted
of unlabeled specimens, empty containers, incorrect lateralities, and
incorrect tissue sites. Nearly 60 percent of errors came from surgical
procedures that included biopsies. All told, identification errors cropped
up in 91 of the 21,351 surgical specimens studied, or 4.3 per 1,000 specimens.
That comes to 0.512 percent of outpatient clinic specimens and 0.346 percent
of OR specimens.
Given the inescapability of human error, those numbers
might not sound so bad —until you remember that in the laboratory,
as Dr. Epstein puts it, "like with airplanes, there is no room for error."
Or, as he and his coauthors write, "when annualized, the rate of occurrence
at this single institution [Hopkins] is 182 mislabeled specimens each
year, all posing significant risks to patient safety." To drive the point
home, they go on to cite a study of the clinical impact of errors detected
through the cytologic histologic correlation process, which found that
at four hospitals, 39 to 45 percent of errors were associated with patient
harm (Raab SS, Grzybicki DM, et al. Clinical impact and frequency of anatomic
pathology errors in cancer diagnoses. Cancer.
The Hopkins team hasn't conducted a followup study
to determine the efficacy of various error-reducing methods; "that'll
be something that I'm sure will be done in the future," Dr. Epstein says.
In the meantime, he and his coauthors offer suggestions, all based on
the assumption that the way to minimize error "is to have a system that's
routinely done over and over again, and to have multiple backups, multiple
fail-safe mechanisms," he says. "Does that mean you catch all of them
[the errors]? Probably not, but hopefully it's a rare event." One backup
method: routine briefing and debriefing checklists that accompany every
OR procedure and include the question "Has the surgical specimen been
Of course, the danger there, as with any checklist,
is that staff will come to regard it as mere busywork. "Forms of redundancy,
like these kinds of checklists, work in decreasing error," says Stephen
Raab, MD, director of the Center for Pathology Quality and Healthcare
Research at the University of Pittsburgh Medical Center, Shadyside. "But
they don't reduce all types of error. And many people just look at it
as excess work. I'm not trying to say it's not beneficial; I'm just pointing
out that it's helpful for some events but not for others."
Another potential error-reducing method, Dr. Epstein
says, is a read-back protocol in the OR for specimens, in which "when
you get something written, the person handling it —let's say the
OR nurse —would then read back to the clinician that it's coming
from a certain site, this is the patient's name," and so forth.
In addition, at Hopkins, a full-time nurse focuses
solely on quality assurance in surgical pathology. "It was such a huge
issue that we decided to have somebody full time devoted to it," Dr. Epstein
explains. "Anytime we have a QA problem, we go to this individual and
it's taken care of." When a surgical specimen error is identified, pathology's
QA individual has a contact nurse who investigates the error, identifies
the correct procedure and tissue, and alerts OR personnel and the surgeon
who performed the procedure.
Laboratories that would like to incorporate this study's
results into their own protocols for surgical specimen misidentification
face a few challenges in particular, Dr. Raab says. First, they simply
don't control the preanalytic phase. "Errors get passed on to laboratories,
so that the laboratory must suffer consequences when they occur," he says.
"How do you address those types of things when they require a broader
approach than what a lab can do individually?"
Lack of standardization is the chief problem the preanalytic
phase poses. "Labs have a number of methods to maintain proper specimen
identification," Dr. Raab notes. "But in the preanalytic phase, there's
a lot less standardization in, say, how specimens are placed in containers,
how the containers are labeled. That's a setup for error." One possible
solution, he says: "quality improvement processes like Lean or Six Sigma."
And then there's the tendency of laboratories to not
consider an error an error. "A lot of times when labs would get misidentified
specimens, they would just call up to the OR and explain that they didn't
receive anything in the container," Dr. Raab says. "This method of solving
the problem often is viewed as a workaround, as it solves the immediate
problem but does not solve the larger problem of specimen mislabeling."
Further, hospitals that compare their error rates to
those reported in the study should examine how their definitions of identification
error differ from that of Hopkins. Not studied at Hopkins was wrong patient
material in a container with a wrong name. "That markedly affects what
the laboratory puts out, and the lab might not even know it," Dr. Raab
Dr. Raab would like to see subsequent studies
link specimen identification errors to outcomes. And while "this is a
good study that defines the problem in one way at one institution," he
says, "it needs to be studied in multiple institutions in multiple ways."
Finally, he says, it's critical to look at best practices and why some
institutions have lower error frequencies than others. "People often have
implemented solutions that other institutions have no idea about."
Anne Ford is a writer in Chicago.