Cases & Commentaries

Transfusion "Slip"

Commentary By Harold S. Kaplan, MD

The Case

A married couple, Mr. and Mrs. M, was brought to
the emergency department (ED) of a Level 1 trauma center after a
half-ton truck that had skidded out of control struck their car.
Mr. M appeared hemodynamically stable, but had bilateral femoral
fractures. Mrs. M had been the driver. Her blood pressure remained
low despite wide-open crystalloid infusions, and she had signs of
peritoneal irritation on exam. Both patients were typed and
crossed, although only Mrs. M appeared to need packed red blood
cells urgently.

The husband and wife patients had been placed in
a large trauma bay with two beds. In the commotion of stabilizing
and assessing both patients, the blood typing tube for Mr. M was
labeled with the sticker for Mrs. M. Once the specimen was labeled
and sent to the lab, this error would normally have been
undetectable based on the standard protocols for handling
transfusion products. By coincidence, however, Mrs. M had
previously undergone a Cesarean section at the same hospital. She
had been typed and crossed at that time. She and her husband did
not share the same blood type (she was Type O and he Type A). The
alert technologist in the blood bank noticed the change in blood
type and inferred that a mistake must have been made. She called
the ED immediately. They agreed to redraw her blood sample for
re-typing, but also requested that O-negative blood be sent the ED
immediately in case the patient deteriorated. Mrs. M thus never
received the wrong blood.

This case represents a very serious near miss.
But for the coincidence of Mrs. M's blood type being on file at the
same hospital, she would have received a potentially fatal
incompatible transfusion matched for her husband's blood type (A)
and not her own (O).

The Commentary

Defects in the process of transfusion currently
pose a greater hazard to patient safety than does
transfusion-associated infectious disease.(1) As is well demonstrated in this case, safe transfusion
begins with the correct collection and labeling of a blood sample
from the right patient.

Miscollected blood samples—the wrong blood
in the tube—are a common problem in blood transfusion. In a
10-nation study of more than 690,000 blood samples from 62
hospitals, the median rate of sample miscollection was 0.5/1,000;
interquartile range 2) Notably, both Sweden and Finland, countries with
national identification systems, had the lowest miscollection rates
(both were too low to estimate reliably).

Mislabeled samples—samples with labels not
meeting locally accepted standards—had an even higher but
more variable rate of error: 1.2 - 17/1000.(2) This variability was most probably due to local
hospital differences in laboratory guidelines for acceptance of
samples. A different study of tested samples rejected because of
mislabeling showed that these samples had a 40-fold higher rate of
blood type discrepancies than correctly labeled samples.(3)
These data indicate that the usual strict rejection policy for
inadequately labeled samples is prudent and should be supported,
despite any perceived inconvenience.

Paradoxically, since inadequately labeled samples
give the lab some degree of warning, they afford less risk than a
correctly labeled, but miscollected sample. In a 10-year study of
transfusion error in New York State, 13% of ABO incompatible
transfusions originated from such samples.(4) Unlike laboratory tests in which there is a clinical
frame of reference (eg, serum bilirubin levels), an incorrect blood
type raises no red flags. Because of this, some transfusion
services do not release blood, other than group O, for routine
transfusion without a prior consistent blood type.(5) In the case under discussion, the routine procedure of
comparing test results of a new sample with the prior blood type
test record was the key to preventing a potentially disastrous
miscollection error.

The disquieting facts that 1/38,000 transfusions
are ABO incompatible, and that half of these mistransfusions result
in an hemolytic transfusion reaction, are obscured by a low
fatality rate (1/600, 000 to 1/1,800,000).(4) Apparently, patients benefit more from good fortune,
and possibly rescue (early investigation, discontinuance of
transfusion, and prompt treatment), than from prevention.

The relatively low fatality rate may contribute
to a lack of mindfulness in blood sample collection. Well practiced
routines such as phlebotomy, although having little cognitive error
potential, are often performed in an "autopilot" or "rehearsed"
mode of behavior. Such autopilot behaviors can be expected to be
compromised by periodic errors due to faulty execution even in the
hands of competent and well intended personnel. Risk factors for
such "slips" include interruption, changed circumstances, or
momentary lapses in concentration.(6)

Feedback to staff of the potential dangers of
phlebotomy error, especially in emergency circumstances, may help
to reinforce a more mindful approach. Although education and
reinforcement are potentially useful and necessary, they may not be
sufficient.(7)
Concern about the reliability of patient and sample identification
has led to promulgation of national standards (8) and proposed federal regulation.(9)

The frequency and potential risk from flawed
patient identification is well recognized as a general medical
issue. The Joint Commission on Accreditation of Healthcare
Organizations (JCAHO) has included "Improve the accuracy of patient
identification" as one of its "National Patient Safety Goals" for
the last 2 years.(8)
JCAHO has recommended the use of at least two patient identifiers
(exclusive of the patient's room number) whenever taking blood
samples or administering medication or blood transfusion.

The hectic environment of an emergency department
increases the risks of patient/sample misidentification. For
example, patients may be unresponsive and unknown, clinical urgency
may lead to samples being collected by pressured staff, and blood
tubes may be handed off frequently or labeled away from the
patient. The simultaneous arrival of two or more patients with the
same surname (as in this case) adds to the potential for error. ED
staffs are acutely sensitive to these issues and have adopted
strategies to help achieve the correct linkage of patient and
sample identification. One approach has been the use of pre-made
matched labels and ID bands.

A variety of other approaches for assuring
accurate identification have been utilized in EDs as well as in
other settings, including: mechanical generation of labels from the
wristband itself; a forcing function requiring reference to a
unique number located only on a patient's wristband for both
specimen labeling and for opening a barrier combination lock prior
to transfusion (10);
and automation using barcode technology to secure both the initial
as well as subsequent phases of the transfusion (and medication)
process.(10,11)

Bar code identification has received the most
attention. The FDA has proposed point-of-care bar code requirements
for medication and blood product administration.(9) Automation has clear advantages in decreasing total
reliance on human vigilance, but it may introduce a new set of
concerns. Technology is fully effective only when introduced into a
properly designed system. Attempting to implement bar coding
without careful system review and appropriate redesign may merely
automate bad practice. For example, one hospital had a dangerous
routine of allowing documentation in advance of medication
administration, specifically, at the time of removing the
medication from a dispensing device or medication cart. Bar codes
were introduced to correct this flawed practice, but the solution
provided merely an illusion of safety and perpetuated the flaw:
extra bar coded patient wristbands were printed in advance to allow
easy scanning of the wristband, medication, and person intending to
administer it, regardless of who or where the recipient happened to
be.(12) A
recent article has documented the various new error modes
attributable to the introduction of bar coding systems.(13) As
is often the case, the introduction of a new technology, intended
to decrease a target risk, may create a new contravening one. This
underscores not only the importance of careful design, but the
cautious monitoring of the effects of change as well.(14)

Just as intended corrections may create an
illusion of safety, so may recovered near misses. The "save" in
this case was due to a combination of luck and an alert technician;
both cannot be counted on to protect future patients. Although the
robust ability to recover from error is of critical importance, the
"glass is half-empty" mindset characteristic of a high reliability
organization (15)
reminds us that an initial failure may still need to be addressed.
In this way, near miss events provide an important "canary in the
mine" early warning of a potential system weakness.

Take-Home Points

  • Systems providing confirmation of
    blood sample typing results against prior test records provide an
    important safety barrier for transfusion.
  • Well-practiced routines, such as phlebotomy, may
    be particularly vulnerable to error when interrupted, or when
    unanticipated signals are encountered.
  • The use of
    automation, including bar code technology, can provide a
    significant increase in reliability of patient and sample
    identification, but this improvement can only be realized when the
    automation is combined with careful system
    design.

Harold S. Kaplan, MD
Professor of Clinical Pathology
Director of Transfusion Medicine
New York Presbyterian Hospital
Columbia Presbyterian Medical Center

References

1. Dzik WH, Corwin H,
Goodnough LT, et al. Patient safety and blood transfusion: new
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2. Dzik WH, Murphy
MF, Andreu G, et al. An international study of the performance of
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3. Lumadue JA, Boyd
JS, Ness PM. Adherence to a strict specimen-labeling policy
decreases the incidence of erroneous blood grouping of blood bank
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4. Linden JV, Wagner
K, Voytovich AE, Sheehan J. Transfusion errors in New York State:
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5. Prevention of
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[ go to related site ]. Accessed January 28,
2004.

6. Langer EJ.
Mindfulness. April Reprint ed. New York, NY: Perseus Publishing;
1990.

7. Callum JL, Kaplan
HS, Merkley LL, et al. Reporting of near-miss events for
transfusion medicine: improving transfusion safety. Transfusion.
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8. National patient
safety goals. Joint Commission on Accreditation of Healthcare
Organizations Web site. Available at:
[ go to related site ]. Accessed February 9,
2004.

9. FDA proposes drug
bar code regulation. U.S. Food and Drug Administration. FDA News
Web site. March 13, 2003. Available at:
[ go to related site ]. Accessed January 28,
2004.

10. Wenz B,
Mercuriali F, AuBuchon JP. Practical methods to improve transfusion
safety by using novel blood unit and patient identification
systems. Am J Clin Pathol. 1997;107:S12-6. [ go to PubMed ]

11. Turner CL,
Casbard AC, Murphy MF. Barcode technology: its role in increasing
the safety of blood transfusion. Transfusion. 2003;43:1200-9[ go to PubMed ]

12. Shea B. The
Patient Safety Discussion Forum. NPSF Listserv. August 8, 2002.
Available at: [ go to related site ]. Accessed January 13,
2004.

13. Patterson ES,
Cook RI, Render ML. Improving patient safety by identifying side
effects from introducing bar coding in medication administration. J
Am Med Inform Assoc. 2002;9:540-53.[ go to PubMed ]

14. Wilde G. Target
risk 2: a new psychology of safety and health. Toronto, ONT: PDE
Publications; 2001.

15. Weick K,
Sutcliffe K. Managing the unexpected: assuring high performance in
an age of complexity. San Francisco, CA: Josey-Bass;
2002.