Cases & Commentaries

Techno Trip

Commentary By Richard I. Cook, MD

The Case

A 70-year-old woman was admitted to a community
hospital after developing confusion and right-sided weakness. A CT
scan of her brain showed an acute subdural hematoma. The hospital
arranged a transfer to large referral center for urgent
neurosurgical evaluation. The radiology department at the community
hospital had recently implemented an electronic picture archiving
and communication system (PACS). Instead of printed films, the
patient was sent with a compact disk (CD) containing copies of
relevant studies. On arrival at the referral center, a right-sided
hemiparesis was confirmed on physical exam. The accepting surgeon
inserted the CD into a local computer. The CT image that appeared
on the screen showed some brain atrophy, small, old strokes, and a
large left-sided subdural hygroma, but no acute hemorrhage. The
surgeon felt that the patient had a stroke, admitted her to the
stroke unit, and consulted neurology.

The next day, a consulting neurologist found a
set of more recent images while scrolling through the PACS disk.
These demonstrated the acute subdural hemorrhage for which the
patient had been transferred. The subdural was urgently evacuated,
and the patient improved after a prolonged period of

The Commentary

This case illustrates a common safety problem
the loss of continuity of care during transfer. Here, information
technology (IT) intended to bridge the gap in continuity actually
contributed to the failure. Health care IT, such as electronic
medical records, computerized provider order entry (CPOE), and bar
coded medication administration (BCMA), is intended to reduce the
incidence of accidents affecting patients. But new technology is
also a potent source of new forms of failure, especially when the
human–computer interaction characteristics of the technology
are not carefully managed.(2,3)

The IT "Gap" Uncovered

Digital radiology (DR) represents a growing area
of health care IT because of the emergence of numerous
digital-format imaging modalities (eg, ultrasound, CT/MRI scanning,
and PET scans). The economies of scale for electronic digital
systems make it convenient to capture and process virtually every
medical image digitally. The proliferation of these images can
become a problem in itself, as practitioners struggle to manage the
many different images generated for a single patient. In healthcare
facilities, captured digital images are stored, transferred, and
viewed across a network of computers called a "picture archive and
communication system" or PACS.(4)

The PACS stores the data needed to reconstruct
digital images without storing the actual images themselves. To
view a particular imaging study, the practitioner selects the
patient and specific image on a terminal connected to the PACS. The
PACS retrieves the corresponding data and draws the image on the
terminal's viewing screen. To make it possible for practitioners to
view a patient's images on computers not connected to the PACS
network (eg, at a different hospital), a CD or DVD containing the
image data for an individual patient is created. The data on this
disk is formatted according to a standard known as DICOM.(5,6)
The purpose of this standard is to make data interchangeable
between different systems, but not all PACS adhere to the standard,
which is changed frequently to accommodate new technology. For this
reason, it is common to include a small program called "DICOM
reader" (7) on
the disk. This program allows almost any computer to generate
images from the data without using a PACS. It may be especially
useful if a patient is transferred to an outside hospital. The disk
may be created so that the DICOM reader program starts
automatically and displays the images found on the disk, often
defaulting to the oldest images first.

In this case, the accepting surgeon likely fell
victim to the technology described above. The DICOM reader
apparently displayed older and, in this instance, less relevant
images. We do not know what sort of directory of images was
available or if the image date or time was displayed, but we can
infer that the surgeon only viewed one set of images.

Technology as a Source of New Failures

Just a few years ago, prior to development of
digital radiology, this type of event was not possible. The patient
would probably have arrived at the receiving hospital with either
physical copies of the CT films showing an acute subdural hematoma
(8) or
without any films at all. If she had arrived without films, it is
likely that a new head CT would have been obtained. In the current
era, however, the same technology that makes high-quality
information available is simultaneously an unexpected source of new
forms of failure.

The source of this event is not human
on the part of the surgeon. Instead, the failure occurred
because the IT design was technology-centered rather than
Although the intention of the designers was for IT to support users
in their work, getting this support requires the users to know a
great deal about how to make this IT work. Some would claim that,
because the IT performed as designed, it did not fail. This case
demonstrates clearly, however, that failure can (and does!) arise
from IT design.

As IT use increases and more access to
information is channeled through IT, these problems will likely
increase in number and severity. The new forms of failure that
result from IT use in health care share common features (10):
the failures are (i) less frequent but more consequential, (ii)
more challenging to detect, and (iii) more difficult to defend

The reason for these qualitative differences in
failures with IT can be traced to the nature of IT itself, and the
way it centralizes the design and interaction features of the
workplace. Manual systems and their filing and record-handling
methods allowed high rates of relatively low-consequence failures.
Handwritten records could be illegible and films misplaced.
Repeated exposure to these problems led workers to devise
relatively straightforward solutions, such as making extra copies,
maintaining "shadow" charts, or redoing lost studies. These
adaptations were inefficient, but they were usually easy to apply
and not unduly burdensome. By preventing these sorts of failures,
IT applications reduce the need for such workarounds. Indeed,
preventing such failures is one reason that IT is now being
deployed. But the deployment introduces new dependencies and
opportunities for accidents.

Unlike the relatively common and easily
understood failures that can occur in manual systems, these
IT-based failures are infrequent but potentially severe. Defenses
against these failures are more difficult to devise and less likely
to be robust.(11)
More importantly, the extended reach and power that IT provides
means that the sources of failure, such as poor design, are far
removed from the failures themselves in ways that encourage people
to view IT-based failures as instances of human ("operator")

The view that technology is relatively infallible
leads failures at the man–machine interface to be attributed
to human error (eg, "the surgeon should look more carefully")
rather than to poor design.(14)
Creating high quality, human-centered technology is difficult and
requires substantial time and effort.(15) Few health care IT designs have received the
necessary study and refinement that characterizes other fields in
which IT design has been quite successful, such as in aircraft
cockpit design. Significantly, design deficiencies identified by
accidents such as this one tend not to lead directly to better
designs but to patches intended to make up for the deficiencies.
One can envision a software fix to change this particular DICOM
reader so that it shows the most recent scan first, or so that a
display of all available scans appears when the disk is inserted
into a computer. It is more difficult to envision a mechanism to
make this an industry-wide practice.

The Syndrome of IT Dependence

The details of digital radiology and IT are only
one aspect of this interesting case. Equally important is the
apparently casual way in which a critical diagnosis was discarded.
One can imagine a brief telephone conversation between the
neurosurgeon and the transferring provider. "I don't see a subdural
here," says the neurosurgeon. The sending physician says,
incredulously, "Are you sure you're looking at the right scan? It's
huge and shows up on at least four slices." This would have been an
opportunity to capture failure in the making. But there was no
dispute about the diagnosis implied by the image because there was
no further communication with the sending physician about the
image. Why?

We can only speculate because the details are
unavailable, but the critical issue is that the neurosurgeon
clearly believed that there had been an error in diagnosis at the
transferring hospital. CT images, like all clinical data, are seen
in context. What exactly was the context for this case? Was there a
history of receiving transfer patients with wrong diagnoses? How
are such transfers usually handled? Is it normal for the sending
physician to speak directly with the neurosurgeon or are there
intermediaries involved? This case report implies that transfer is
the end of a process and that further contact between the sending
and receiving physician is not expected. Is this really the case?
How are disagreements about diagnosis handled? What sort of
scrutiny did the images receive when the expected subdural hematoma
did not appear? Did the neurosurgeon show the image to an ER
colleague and receive confirmation that the pattern was indeed more
consistent with a stroke?

As we begin to inquire into the context that
surrounds transfer of patients, we discover that this case is far
from simple. In the final analysis, the IT intended to bridge what
threatened to become a gap in the continuity of care actually
contributed to it. As for countermeasures, our attention is
initially drawn to the details of the computer systems and their
operation. But effective defenses against future events like this
one may depend on making direct physician-to-physician contacts
more reliable. Improving the ability of practitioners to
communicate across institutional and organizational boundaries,
increasing the quality of opportunities for consultation and
clarification, and reducing the disincentives to such
contacts—although more difficult to achieve—are likely
to make the system itself more robust.

The Future of IT

What does this case imply about the future? The
Federal government insists that adding IT to hospitals will make
patients safer.(3)
Surprisingly, only a few studies of IT-related failures exist in
the medical literature.(16,17)
In part, this is due to challenges in reporting sporadic or
"isolated" events when human error is readily available as a target
of blame. What is clear, however, is that IT is a double-edged
sword. According to the USP, human-computer interaction is already
a leading cause of medication errors!(18)

Virtually all health care facilities are in the
midst of adding clinical IT, often at great cost. The eagerness
with which some groups have embraced IT is worrisome, and the
failure rate of these projects is high. Mandates from groups such
as the Leapfrog organization (19)
stress the advantages of IT but do not acknowledge that IT itself
is generating new forms of failure. Cases like this one demonstrate
that IT in health care requires more than simply adding
"computerization" to make things faster, more efficient, and safe.
While the potential of having instant and easy access to patients'
medical records is very attractive, creating and maintaining
user-centered automation poses a major challenge.

Take-Home Points

  • Adding IT does not eliminate failure
    but, instead, changes the type, frequency, and severity of
    failures, often in unpredictable and surprising ways.
  • Creating robust IT depends on designing
    health care computer systems to be user-centered rather than
  • Although failures involving IT are often
    regarded as human (operator) error, these failures actually arise
    from poor human-computer interaction.

Richard I. Cook, MD
Associate Professor, Department of Anesthesia and Critical Care
Director, Cognitive Technologies Laboratory
University of Chicago


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