Transcript poka-yoke

‫بسم هللا الرحمن الرحيم‬
Poka Yoke
Mistake Proofing
Col. Dr. Jamal Hommadi
PURPOSE
Introducing Poka yoke as one of the effective quality design
techniques experienced in manufacturing business to the quality of
healthcare.
Introduction
• It has been more than 15 years since the Institute of Medicine (IOM) released its
landmark report, To Err Is Human,
• Building a Safer Health System, which galvanized attention on the serious and
pervasive problem of errors in health care.
• Research into the causes of medical errors and ways to prevent them increased
dramatically in the ensuing years after publication of the IOM report in 1999.
Introduction
The Joint Commission commented that:
“it assumes that no matter how knowledgeable or careful
people are, errors will occur in some situations and may
even be likely to occur.”
Introduction
Traditional quality control methods identify “variation” as the
enemy.
Recent experience has shown that mistakes are the most common
cause of problems in health care as well as in other industrial
environments.
The best methods for controlling variation and complexity, is by
mistake proofing.
Introduction
• Shingo did make a clear distinction between a mistake and a defect.
• Mistakes: are inevitable; people are human and can not be expected to
concentrate on all the time, or always to understand completely the
instructions they are given.
• Defects: result from allowing a mistake to reach the customer, and are
entirely avoidable.
World of Mistakes
*
*
MISTAKES:
they are inevitable
people are human and can’t be
expected to concentrate
on the work in front of them
100% of the time
DEFECTS:
Defects are a direct
result of allowing a mistake to reach the
customer defects are entirely avoidable
taken from the book, Shingo 1986 p.50
T0 Err Is Human!
The Institute of Medicine2 estimated in 1999 that between
44 000 and 98 000 people die in hospitals each year due to
mistakes, and that medical mistakes are the 8th top killer
in the nation.
In the same report hospital errors alone have also been
estimated to cost the nation $8.8 billion a year.
VARIATION: A SOURCE OF DEFECTS
MISTAKES
THE MAJOR SOURCE OF DEFECTS
What is Poka-Yoke (ポカヨケ) ?
Poka-Yoke was coined in Japan during the 1960s by Eng. Shigeo
Shingo who was one of the industrial engineers at Toyota.
is a Japanese term that means "mistake-proofing". avoid (yokeru) mistakes
(poka).
definition
Mistake-proofing: is the use of process or design features to
prevent errors or the negative impact of errors.
Mistake proofing is also known as poka-yoke (pronounced
poka-yokay), Japanese slang for “avoiding errors.”
-Shigeo Shingo said:
“Preventing the act of forgetting what
you have forgotten”
Why is “Poka-Yoke” an Important
Concept?
• Maintain Customer Satisfaction & Loyalty
• There is always a cost associated with defects!
Mistake-Proofing Approaches
There is no comprehensive typology of mistake-proofing. Tsuda lists
four approaches to mistake-proofing:
1. Mistake prevention in the work environment.
2. Mistake detection (Shingo's informative inspection).
3. Mistake prevention (Shingo's source inspection).
4. Preventing the influence of mistakes.
Tsuda's approaches are similar to those recommended by the Department of
Health and the Design Council in England:
1. Prevent user error from occurring.
2. Alert users to possible dangers.
3. Reduce the effect of user errors.
Human Error
Rasmussen and Reason divide errors into three types, based on how the
brain controls actions:
1.
skill-based actions.
2.
rule-based actions.
3.
knowledge-based actions.
Their theory is that the brain minimizes effort by switching among
different levels of control, depending on the situation.
skill-based actions.
• Common activities in routine situations are handled using skill-based
actions, which operate with little conscious intervention.
• These are actions that are done on “autopilot.”
• Skill-based actions allow you to focus on the creativity of cooking rather
than the mechanics of how to turn on the stove.
• Errors that occur at the skill-based level are comparable to Norman's
concept of slips.
Slips
Rule-based actions
• utilize stored rules about how to respond to situa
tions that have been previously encountered.
• When a pot boils over, the response does not
require protracted deliberations to determine what
to do.
• You remove the pot from the heat and lower the
temperature setting before returning the pot to the
burner.
Knowledge-based actions
• When novel situations arise, conscious problem
solving and deliberation are required.
• KBA are those actions that use the process of
logical deduction to determine what to do on the
basis of theoretical knowledge.
• Every skill- and rule-based action was a
knowledge-based action at one time.
few of the many possible nurses
errors
• Nurses could inadvertently select the wrong medication, misread the
prescription, select the wrong dose, deliver the medication to the wrong
patient, select the wrong number of capsules or pills, or inadvertently
drop a pill without detection.
• Bates et al14 stated that 6.5% of the patients
entering hospitals experience adverse drug
effects due to prescription errors.
• Lapworth and Teal cited two studies where
clinical laboratory mistake rates were in the range
of 0.3–2.3%. Pellar et al found that mistakes were
a leading source of delays.
• The Harvard Medical Practice found that 3.7% of hospital patients
received disabling injuries due to medical treatment errors and 58% of
these injures were caused by errors in management.
• The Quality in Australian Health Care reported that 16.6% of hospital
admissions were associated with adverse events of which, 50% were
highly preventable.
Knowledge in the Head
vs.
knowledge in the World
• Norman divides knowledge into two categories:
• 1. Knowledge in the head: is information contained in
human memory.
• 2. Knowledge in the world: is information provided as
part of the environment in which a task is performed.
knowledge in the World
•oxygen and nitrous oxide.
completely
apparent
Partially
apparent
Concealed
The domino theory of accident causation
adapted from Bird (1974)
safety/loss of
control
Basic intermedia
causes te causes
accident
causes
Injury
problem
“The occurrence of an [accident] is the culmination of a series of events
or circumstances, which invariably occur in a fixed and logical order”
Safety / loss of
control
Basic
causes
intermediate
causes
(Heinrich et al.,1980)
accident
causes
Injury or
problem
Poka Yoke at HR
Are We Hiring People Who Will
Thrive in a Lean Culture and
Contribute to Our Success?
Do we have a standardized and efficient hiring process?
Example: MMU
• Medication is placed in order of the MAR (Medication Administration
Record) so it is easy to find and
Example from Lab.
Red specimens = Hospital registered
Patient (stat)
Green specimens = (Routine)
mixed up
Tube racks color coded so that they do
not get
mixed up
Reminders
This sign reminds staff to send a
report at the certain time of a day
Prevention
• NG Tube - Shows how
NG tube cannot be
connected to an IV
port
Prevention
• A single action one
hand sharps
protection to prevent
the user from
• being poked
Prevent error
• Pre-mix scald anti-scald
valve
Detect error
Infant abduction sensor locks the
exit in case of an abduction
Esophageal intubation detector
Sign your site
• The holes for the pins are
located at 12
• o’clock and 5 o’clock. Also,
the oxygen outlet is
• green, and the medical air
outlet is yellow.
• The medication dispenser
dispenses medications
and detects when they
are removed.
• Clearly visible sinks
encourage handwashing.
• Handrails are present from
the bedside to
• the bathroom.
Standardized headwalls allow staff
members to work on 'auto-pilot'.
• A patient's medical
records can be stored
• in this wristband.
Wristbands can contain
color photos,
symbols, and other patient
information
• “Decoupling” means separating an error-prone
activity from the point at which the error becomes
irreversible.
Tools
• Just Culture: refers to a working environment
that is conducive to “blame-free” reporting but
also one in which accountability is not lost.
• Root cause analysis (RCA) is a set of
methodologies for determining at least one cause
of an event that can be controlled or altered so
that the event will not recur in the same situation.
• FMEA and FMECA are “virtually the same,”
except for a few subtleties that have been more
or less lost in practice (hereafter simply referred
to as FMEA). These two related tools enable
teams to analyse all of the ways a particular
component or process can fail, predict what the
consequences of that failure would be, and
prioritize remedial change actions.
• A fault tree is a graphical representation of the
relationships that directly cause or contribute to
an event or failure.
• Fault trees are a top-down approach. A fault tree
starts with an event and determines all the
component (or task) failures that could contribute
to that event.
Knowing What Errors Occur, and Why, Is Not Enough
The golden role of thumb in Poka yoke is that:
1. Knowing errors is not enough.
2. Do not accept errors.
3. Do not do errors.
4.
do not pass errors.
5. Redesign the process that causes errors.
An error proofing
system should consider
these 3 simple rules
Don’t accept a
defect
Your
supplier
Don’t pass on a
defect
You
Don’t do
a defect
Your
customer
JCI provides three questions that must be answered at
the “redesign the process” step:
1. How can we change the process to prevent this failure
mode from occurring?
2. What design/redesign strategies and tools should we
use? How do we evaluate their likely success?
3. Who should be involved in the design/redesign
process?
Conclusion
• Implementing mistake-proofing in medical
environments will probably be more challenging
and difficult than implementing the same
techniques in manufacturing.
• The difficulties are not provided as excuses or
reasons why mistake-proofing should not be
implemented but rather as guides to what can be
expected as implementation progresses.
• mistake-proofing will fit into a variety of existing
efforts to improve patient safety.
Conclusion
Donald Berwick (IHI) said:
…We are human and humans err. Despite outrage, despite
grief, despite experience, despite our best efforts, despite
our deepest wishes, we are born fallible and will remain so.
Being careful helps, but it brings us nowhere near
perfection…The remedy is in changing systems of work.
The remedy is in design. The goal should be extreme
safety. I believe we should be as safe in our hospitals as
we are in our homes. But we cannot reach that goal
through exhortation, censure, outrage, and shame. We can
reach it only by commitment to change, so that normal,
human errors can be made irrelevant to outcome,
continually found, and skilfully mitigated.