Patient Safety in Anatomic Pathology
Moderator: Peter Furness
Section 3 -
Addressing National Patient Safety Goals in Surgical Pathology
Richard J. Zarbo
Henry Ford Hospital
Department of Pathology
Detroit, MI USA
- Identify the top 3 national ( US ) patient safety goals to be implemented in surgical pathology in 2006.
- Appreciate the magnitude and
importance of preanalytic patient identification errors.
- Understand a framework for
producing standardized, documented and issued amended reports
- Identify mechanisms for timely
communication and documentation of significant or unexpected surgical pathology diagnoses.
The topic of patient safety became an important subject in medicine with the publication in 1999 of
the United States Institute of Medicine's report on medical error and its subsequent report on the
general state of quality of health care in 2001. This focus on error reduction also extends to the
laboratory where patient's safety can be summarized as 'doing the right thing, at the right time, for the
right patient.' The patient safety movement builds on, and is an evolution of previous quality
movements, such as quality control, quality assurance and quality improvement, but necessarily focuses on
that portion of the Hippocratic oath calling us "above all, to do no unnecessary harm." Unfortunately,
humans err often and therefore, error is a common fact of life. Approaches to patient safety take this
fact to heart, focusing not on the human, but instead on the redesign of systems to minimize the
consequences of inevitable human error. The most common causes of error from root cause analyses are
those of mis-communication, poorly defined connections between individuals, inappropriate pathways of
action, low cultural expectations, and poor teamwork. Clearly, the quest for improved quality and
patient safety is never ending, given the current design of systems and human nature.
The College of American Pathologists elaborated on its laboratory patient safety goals in late 2005.
Those four goals which each laboratory must document that it has addressed by evaluation and monitoring
of the processes involved include the following:
- Patient and sample identification at specimen collection, analysis
- Timely identification, communication and correction of errors.
- Verification and communication of life threatening, life altering
- Coordination of the patient safety role in health care
Defects in the pre-analytic phase of testing, namely that of specimen labeling and lab tag
requisition accuracy, are fairly common. In the 1993 Q-Probes study of over one million case accessions
from 417 laboratories, the overall specimen defect (deficiency) rate was 6%. The most common defect was
that of incorrect or missing information or no clinical history provided with the specimen. Fewer cases
had defects in handling or were lost in transportation. However, notably 9.6% of specimens had defects
in patient identification and, in fact, 1.8% had no label on the specimen container at all.
So how does the magnitude of these defects translate into the Six Sigma world of defects? Placed on
that scale where a defect rate of Six Sigma translates to 3.4 defects per million, the aggregate
percentage of defective surgical pathology cases would equate to a 1-2 Sigma performance or roughly
60,000 defects per million. To put this in context, the safety of the American Space Shuttle Program,
recognizably flawed, would be 20,000 defects per million, or roughly 2% error (two shuttles lost per 103
flights) (2 sigma). This is exceeded by the rate of mishandled bags affecting 1% of passengers on
conventional airflights at 6000/million at a 2-3 sigma defect rate.
So, more importantly, what proportion of defects in surgical pathology are related to
mis-identification or lack of identification of the patient? In our own examination of 430 amended
surgical pathology reports from three years of practice, mis-identification was the second most common
defect that resulted in an amended report. Interestingly, non-diagnostic report defects were far and
away the most common deficiency and frank mis-interpretation defects ran third, close in frequency to the
But is this method of surveillance from amended reports a true reflection of identification error? If
we make use of our experience in the blood bank where we have previous blood types on record, we can
extrapolate a blood collection mis-identification rate of roughly 1,000 per million. Similarly, using
morphologic recognition of tissues that do not match the anatomic site or are from patients known not to
have been biopsied, the surgical pathology defect rate is about 240 per million mis-identified specimens
processed per year. Clearly, there is a very wide range of mis-identification taking place under our
watch, the true magnitude of which can only be crudely estimated at this point in time.
These identification errors may arise anywhere in the test cycle. Although we often impugn the
pre-analytic component of testing, that is a specimen with defective identification submitted to the
laboratory, in fact, a significant number of mis-identifications take place within the laboratory: in
accessioning, tissue and slide processing, at the pathologist's microscope and at transcription.
Further, additional opportunities for mis-identification take place in the post-analytic phase of paper
or computer reporting. All these aspects of process involve humans, multiple handoffs, and inevitable
slip errors whereby we often form the appropriate goal but go about the action in an inappropriate
manner. These mis-identification errors may be further compounded by quick and superficial fixes to
relabel specimens in the absence of assured identification.
To minimize the chance for this type medical disaster, regulatory agencies currently require two forms
of patient identification on each specimen container and requisition. It is also suggested that the
addition of a barcode be employed and that handwritten or manual specimen label identification and/or
reentry of identifying numbers at accession be avoided. For those of us who design the systems in which
we work, simplification of lab processes and built-in redundant checks can be extremely helpful in
avoiding mis-identification errors throughout the surgical pathology process. More recent molecular
techniques may also allow us to verify tissue identity at the DNA level, rather than making
identification reassignments based on clinical assumptions.
A quality monitor of defined surveillance for and documentation of identification errors is a very
useful continuous monitor. It can capture not only errors that have escaped the laboratory but also
those common near-misses that have been caught and corrected in process. This is useful information that
may be used to focus education of personnel on proper labeling and identification, both within and
outside the boundaries of the laboratory. Efforts to establish continuous education, directed
communication and standardized protocols in processes are all helpful in reducing identification error.
Adoption and implementation of a specimen labeling and rejection policy with defined opportunities for
specimen rehabilitation and/or relabeling are also appropriate. In our own institution, implementation
of such a specimen labeling and acceptability policy dramatically reduced the number of specimens with
identification defects by over 98% in a few short months.
Surgical Pathology Errors and Amended Reports
Through our ongoing Agency for Healthcare Research and Quality grant funded investigation of anatomic
pathology error, we have developed a taxonomy of report defects from the analysis of amended reports.
That taxonomy includes four categories of defective interpretation, defective identification, defective
specimen and defective report. Using this four-part taxonomy we have retrospectively reviewed all
amended reports generated for three years, spanning nearly 150,000 surgical pathology cases. We find
that the amended report frequency ranges from 2.6-3.6 amended reports per 1,000 issued. This has been a
fairly consistent rate in our practice, over a period with no major process changes. Using this
taxonomy, report defects are the most common, 28-44%. These include reports with erroneous or missing
non-diagnostic information, dictation or typing error, report delivery error or computer format,
transmission or upload error. The second most common defect is that of specimen or patient
mis-identification which ranges from 27-38% of the amended reports. These identification defects can be
further classified as those at the patient level, tissue, laterality (right vs. left) or anatomic
location specification. The third most common error is that of mis-interpretation, ranging from 23-28%
of amended reports issued. Interpretation errors can be classified as microscopic false-negatives
(undercall), microscopic false-positive (overcall), or microscopic misclassification. The undercalls and
overcalls may be further classified as those dealing with primary diagnoses (positive-negative or
benign-malignant) or secondary diagnostic characteristics such as tumor grade, stage, and margin. And
lastly, defects related to the specimen itself or its handling are the fourth most common root cause of
amended reports, counting for 4-10%. Defective specimens include those that are lost, of inadequate
volume, size, gross description, erroneous measurement or extraneous tissue. This category also includes
inadequate representativeness, sampling at the tissue block or slide level and those cases in which
pertinent ancillary diagnostic studies are not initially done.
From this analysis of these amended surgical pathology reports over a three year period, we conclude
that the overall amended report defect rate is 2.9 per 1,000 surgical pathology cases. Roughly 5%, or 1
in 20 reports, had multiple errors using the taxonomy presented. 15-18% of the amended reports were
generated from tumor boards and the remainder from quality assurance review activities and
clinician-initiated reviews. The high value of tumor board review is reflected in the significant
percentage of the interpretative errors (52-73%) that this process detected. However, the question of
the timing of the discovery of these interpretative defects, in relation to subsequent patient diagnostic
and therapeutic efforts awaits a true outcome analysis. Clearly, errors commonly occur and they provide
rich material for pathologists to track, trend, present for educational purposes and stimulate thinking
about process and system redesign.
The CAP inspection checklists call for "documented systems to ensure that all revised reports for
previously reported incorrect (erroneous) patient results are identified as revised, corrected or amended
on all forms of patient reports and that when revised results are reported that the revised and original
data are clearly identified as such and that the original data are accessible to the user for
comparison." The current state of amended reports is that there is no standardization of terminology
such that terms revised, corrected, amended, supplemental, addendum and additional may be appended to
these reports with mixed meaning. Further, there are system limitations pertaining to whether a
laboratory issues paper or electronic reports or both. Consideration should be given to whether these
paper reports need to be withdrawn everywhere they have been issued or retrieved, then left in place,
stamped 'disregard – issued in error'. Or, in the case of electronic reports, one should know whether
the electronic report remains within the computer system or is overlaid with one that will require
specific wording retaining the original erroneous diagnosis in some form. Other considerations are
specific to laboratory information systems which may dictate what that second issued report is called and
how the original information is presented, if at all. In addition, it is useful to document how amended
reports are subsequently presented in the hospital information system and the sequence in which those
second reports are presented to the caregiver. We have found in our own environment that creation of an
amendment dictionary menu aligned with the error taxonomy previously presented has been helpful in
standardizing the approach to amended reports, the documentation of the cause of the error and the
subsequent root cause analysis. We classify our amended reports as interpretation (diagnosis),
identification (mis-identification), specimen, report and information technology (computer) reasons for
amendment. Further, for the issuance of amended reports for diagnosis or mis-identification, there is a
requirement that the licensed caregiver notified be documented within the body of the amended report, as
well as the date and time.
"Critical Values" in Anatomic Pathology
The CAP patient safety goal, calling for "verification and communication of life threatening or life
altering information such as malignancy, HIV, serious infections, and critical values" is one that can
met in a variety of ways. Specific checklist language calls for laboratories to have "procedures for
immediate notification of a physician or other clinical personnel responsible for patient care when
results of certain tests falls in established "alert" or "critical" ranges." Further, there is a call
for "documentation of notification of the appropriate clinical individual of all critical values and for
the laboratory to have a verifying "read-back" of critical values that are communicated verbally or by
phone." These regulations are those to which the clinical laboratories that report critical values
adhere in the United States.
The specific regulation addressing anatomic pathology results calls for a "policy regarding timely
communication and documentation thereof of significant or unexpected surgical pathology findings."
Further, the regulation specifies that "diagnoses defined as significant or unexpected, if any, should be
determined by the pathology department in cooperation with the local clinical medical staff," affording a
certain degree of local autonomy. It also states that "consideration should be given to assuring, with
reasonable effort, prompt communication of such results by telephone, pager or other system and that
there should be documentation of date and time of such special notification which may be included in the
pathology report or laboratory files." We believe that the last requirement should include the
documentation of the person notified for all cases in which the diagnosis or identification of any part
of the case has been changed.
In dealing with these regulatory requirements, we have clarified in our AP policy that the vast
majority of anatomic pathology significant values are, in fact, not 'critical values' and do not require
a 'read-back' as performed in the clinical pathology laboratories. We have designated these priority
diagnoses as "action-alert" diagnoses in anatomic pathology. This signifies diagnoses that are elevated
to an enhanced notification and documentation status. In fact, in national Q-Probes studies and in our
own last AP customer satisfaction survey of 2005, this was the number one physician request for more
effective communication of abnormal results. We have taken the approach that these notifications may be
made either by phone call with documentation of 'who, what and when' or by use of our electronic medical
record 'in-box' notification whereby results so posted require physician closure and subsequent
documentation or after a certain period of time, transmission of that notification to a back-up
caregiver. Currently, our list of action-alert diagnoses includes:
- Giant cell arteritis in temporal artery biopsy (positive value)
- Significant microorganisms e.g. CMV, significant fungi including
angioinvasive fungi, and organisms in physiologically sterile body sites.
- Gestational endometrium without placenta or fetal tissue.
- Completely unexpected or first time diagnosis of malignancy.
- Evidence of perforated uterus or other viscus.
- Cytopathology non-gynecological and fine needle aspiration biopsies
that are suspicious or positive for malignancy.
- Cytopathology Pap smear diagnoses of HSIL, suspicious or positive
- Amended reports issued for patient mis-identification or changed
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