Transcript Cognitive Error in Medicine Pat Croskerry MD PhD CFPS Annual

An Introduction to
Patient Safety
Pat Croskerry MD, PhD
Patient Safety Officer Course
CPSI, Ottawa April 2011
‘It may seem a strange principle
to enunciate as the very first
requirement in a Hospital that it
should do the sick no harm’
Florence Nightingale
Notes on Hospitals, 1859
The
case of
Sandra Geller
2004
Sandra Geller
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68 y/o with CAD
Elective CABG - -> Sx went well
Lung infection developed on respirator
Small CVA
ARF -> short term renal dialysis
2 weeks in ICU, ready for floor
Generalised seizure
Sandra Geller
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Intubated without difficulty
Did not desaturate significantly
CT scan – nothing new
Remained in a coma for 2 weeks
Life support withdrawn in accordance with her
wishes in living will
• Died
The Slip in her Care
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1 hour after seizure
Nurse cleaning up bedside table
Found two medication vials
Similar size, shape, with similar labels
One was heparin, the other insulin
This
is an example of
an adverse event (AE)
Adverse Event
An event of commission or omission
arising during clinical care causing
unintended physical or psychological
injury to a patient, their family or friends,
and not due to the underlying disease
process. It may result in prolonged
hospital stay, temporary or permanent
disability, or death.
Adverse Events
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Delayed or missed diagnoses
Medication errors
Wrong side surgery
Wrong patient surgery
Equipment failure
Patient identity
Transfusion errors
Mislabeled specimen
Patient falls
Time delay errors
Laboratory errors
Radiology errors
Procedural error
Sexual or physical assault
• Lost, delayed, or failures to follow
up reports
• Retention of foreign object
following surgery
• Contamination of drugs, equipment
• Intravascular air embolism
• Failure to recognise hypoglycemia
• Failure to treat neonatal
hyperbilirubinemia
• Stage lll or lV pressure ulcers
acquired after admission
• Wrong gas delivery
• Deaths associated with
restraints/bedrails
How do we know
an AE has occurred?
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Voluntary reporting
Mandatory reporting
Informal
Direct observation
Patient complaint
Medico-legal action
Medical records
Chart review
Determinants of Adverse Events
• The People
• The System
The
System
HFE
Healthcare
Workers
Adverse
Event
Sources of System Error
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Overall culture
Education/Training
System design / HFE
Resource availability
Demand/Volume
Medical environments are highly
variable and the safety threats
and the barriers to control them
vary from one to another
From the relative quiet of an
oncology clinic…
Long waits to be seen
Noise
Phone calls
Fatigue
Teaching obligations Many sick patients
Work area design
Dim lighting
Faulty communication
Multi-tasking
Shift work
Constant interruptions
Need to hurry
Lack of resources
Faulty or missing processes
Uncertainty
Full bladder
Home stress
New trainees
Multi-tasking
Hunger Violence
Ambiguity
Short-staffed
Technology
won’t work
Availability of
consultants
Angry patients
How long have we been aware of
adverse events?
120
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1939
1970
Year
1998
MILESTONES
1991 Harvard Medical Practice Study
1995 Quality in Australian Health Care Study
1996 Annenberg conferences
1999 Colorado / Utah Study
1999 IOM Report: To Err is Human
2000 BMA/BMJ London Conference on Medical Error
2000 SAEM: San Francisco Conference on EM Error
2000 NHS report: An Organization with a Memory
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2001 1st Halifax Symposium on Medical Error
2001 RCPSC National Steering Committee on Patient Safety
2002 RCPSC Report: Building a Safer System
2004 Canadian Institute of Patient Safety
2004 Baker-Norton Report on Canadian Adverse events
2002–9 Halifax Series of Symposia on Patient Safety
Study
Adverse
Event Rate
(%)
% Due to
error or
negligence
Number
Of
Patient Charts
HMPS
3.7
27.6
30,121
QAHCS
16.6
51.2
14,210
UK
11.7
48.0
1,014
NZ
6.3
36.1
6,579
Denmark
9.0
Canada
7.5
36.9
3,745
Sweden
12.3
1967
10%
On average, about one in
ten hospitalised patients
suffer an adverse event
50%
On average, about half of
all adverse events are
considered preventable
Anesthesia as the Principal Cause
of Death
1948 (U.K.) Macintosh: ‘all anesthetic deaths are
preventable’
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1955-59 (U.S. Phillips)
1961 (U.S)
1982 (U.K.)
Current
~ 6%
~0.12
~ 0.01
~ 0.0005 (5 per million)
Comparison of Risk in Health Care
With Other Industries
Lives Lost/ Year
HIGH RISK
(>1/1000)
MODERATE
RISK
HEALTH
CARE
MINIMAL
RISK
(<1/100,000)
Driving
Bungee
jumping
Chemical
Manufacturing
Commercial
Aviation
Number of Encounters
Nuclear Power
Modified from R. Amalberti and L. Leape
The extent of the problem in the US
• 100,000 deaths annually due to medical errors
(7 th leading cause of death)
• Revised estimate (2004) put rate at 195,000
• Motor vehicle accidents - 43,000
• Breast cancer - 42,000
• AIDS - 17,000
• Error cost in mid-1990s: $29 billion annually
Error problem
The Canadian Adverse Events Study:
the incidence of adverse events in
hospital patients in Canada
Baker, Norton et al., CMAJ 2004
Canadian Adverse Events Study
(CAES)
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In the year 2000
20 acute care hospitals
5 provinces (BC, Alberta, Ontario, Quebec, NS)
3,745 adult patient charts
Medical and surgical admissions
No pediatric, obstetric or psychiatric cases
CAES
• Adverse event rate 8%
Extrapolates to 185,000 annually
• Preventable adverse events ~ 37%
Extrapolated preventable AEs annually ~ 70,000
• 5% AEs had permanent disability
Extrapolates to 3422 preventable annually
• Death rate from preventable AEs was 0.66% with 95%
confidence interval of (0.37-0.95)
• Extrapolates to preventable deaths in range 9000-24,000
annually
CAES
• Patients with an AE spent additional 6 days
in hospital
• Average cost ~ $5000
• Total preventable AEs annually ~70,000
• Potential cost saving >$300 million
Why has it taken until now
to find this out?
Striving for Perfection
‘Among the powerful barriers to
making progress in patient safety
is an attitude of complacency
induced by the rarity of serious
events and the general human bias
toward assuming that things will
work as they are supposed to’.
Lucian Leape, 2002
The
(historical)
Culture of Silence
Culture of Silence
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First do no Harm
Denial
Power to Heal
Peer Disapproval
Professional Censure
Legal Implications
Livelihood
Discomfort
Disclosing an adverse event
(an example from the ED)
Ergonomics
(Human Factors Engineering)
Poor ergonomic design in healthcare
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Space organization
Information Technology
Hand-wash stations
Lighting
Monitors
Infusion pumps
Poor Ergonomics
• Inconvenience worker and may
make workplace unsafe
• In healthcare setting may also
make patient unsafe
WHY NOT DISCLOSE
ERROR ?
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Error is trivial
Most errors do not cause harm
Patient is ignorant about the concept of error
May impair the patient’s trust in the system
May force search for alternatives
Change
began about 15 years ago
Culture of Silence
to a
Culture of Safety
Two Major Errors in
Sandra’s Case
• Medication error
• Cognitive error
Prescription
Transcription
Dispensing
Administration
Monitoring
The
Medication
Process
Medication process
• Up tp 50 steps between a doctor’s decision
to order a medication for a hospitalized
patient and the actual delivery of the
medication to the patient
• Even if all 50 go right 99% of the time, the
chances of an error are about 40%
Prescription
MEDICATION
ERRORS
Transcription
Dispensing
Misconnection
Administration
Connection
Errors
Disconnection
Monitoring
Medication Error Components in
Sandra’s Case
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Multi-tasking
Attentional capture
Common final act
Look alike vials
Tight coupling
Lack of forcing function
Other
Cognitive Error Components in
Sandra’s Case
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Setting
Patient well known
Search satisficing
Premature diagnostic closure
Metacognitive failure
Other
3 Main Categories of Error in
Individual Performance
• Cognitive
• Procedural
• Affective
Procedural Error
• Error which arises in the performance of a
particular procedure
• e.g. sterile technique, suturing, cast-application,
chest tube, LP, central line, intubation
• Mostly combined visual/motor/touch skills
• Critically dependent on teaching/experience
• Requires maintenance
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Skill 72
Acquisition
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Weeks
Bryan and Harter, 1899
Laparoscopic Choleycystectomy
CBD injuries
by X20 after ~12 cases
The Hernia Factory
(Boutique hospital)
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Shouldice hospital
About a dozen physicians
Some without surgical training
Each does ~ 600-800 operations/year
Hernia operation ~ 30-45 minutes
Recurrence rate ~ 1% (vs 10-15%)
Cost ~ 50% less
Affective Error
Occurs when physician’s emotional state
influences clinical decision making
… if your mental state is disturbed,
full of emotion, it is very difficult
to cope with problems, because the
mind that is full of emotion is
biased, unable to see reality. So
whatever you do will be
unrealistic and naturally fail.
23 November 2010
Our affective reactions to patients
are often our very first reactions,
occurring automatically and
subsequently guiding information
processing, judgment, and decision
making…
Zajonc, American Psychologist, 1980
The Borderline Patient
‘The patient presenting with a personality
disorder may often be recognized by the
characteristic effect the interaction has on the
physician and medical staff. Antisocial
patients, for instance, are disliked immediately.
They seem to be in control of their behavior,
unlike psychotic or depressed patients, but
nonetheless have repeatedly engaged in
maladaptive behavior’
Sources of Affective Error
• Ambient - induced
Transitory affective states
Environmental
Stress, fatigue, other
• Clinical situation - induced
Counter Transference
Fundamental Attribution Error
Specific affective biases
• Endogenous
Circadian, infradian, seasonal mood variation
Mood disorders
Anxiety disorders
Emotional dysregulatory states
Lancet, 2008
Acad Emerg Med, 2007
Diagnostic Failure: A Cognitive
and Affective Approach
Research
In Advances in Patient
Safety: From
to Implementation, 2005
Pat Croskerry
Abstract
Diagnosis is the foundation of medicine. Effective treatment cannot
begin until an accurate diagnosis has been made. Diagnostic
reasoning is a critical aspect of clinical performance. It is vulnerable
Cognitive Error
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A failure in rational/logical thought
Often due to biases or ‘dispositions to respond’
About fifty known biases exist
They are universal
They are predictable
They can be corrected (cognitive de-biasing)
Origins of diagnostic error in 100 patients
(Graber et al 2004)
No-Fault Factors
Only
(7%)
System-Related
Error Only
(19%)
Both SystemRelated
And Cognitive
Factors
(46%)
Cognitive Error
Only
(28%)
30 Cognitive Errors
Aggregate bias
Anchoring
Gender bias
Psych-Out Errors
Hindsight bias
Representativeness
Ascertainment bias Multiple
alternatives
Availability
Omission bias
Search satisficing
Sutton’s Slip
Base rate neglect
Order effects
Commission bias
Outcome bias
Unpacking principle
Confirmation bias
Overconfidence
Vertical line failure
Diagnostic creep
Playing the odds
Attribution error
Posterior prob.
Gambler’s Fallacy Premature closure
Triage-Cueing
Visceral bias
Ying-Yang Out
Zebra retreat