Date post: | 22-Jan-2018 |
Category: |
Health & Medicine |
Upload: | scgh-ed-cme |
View: | 891 times |
Download: | 0 times |
EFFECTIVE DECISION MAKING
Tom
ERRORS ARE DUE TO FLAWS IN
THINKING, NOT TECHNICAL MISTAKES
“Always look both ways when you go through a green light”
Case 1
60 year old man transferred from Albany hospital BG: RA on MTX, obese, ex-smoker
Presented to Albany 5/7 prior
SOB / cough / fevers – treated for CAP
Associated CP Troponin +
Dual antiplatelets commenced
Day 4
Day4: Episode of sig. hypotension and “coffee ground” vomit
Hb 120 70
Stabalized post-fluid and blood resuscitation
Transferred to SCGH for gastroscopy
PPI infusion
Day 5
S/by Gastroenterology & Cardiology
PR –ve, not for scope
Continue dual antiplatelets
Admitted under MAU
Patient feels well
Hb 75 despite 2 x PRBC
No further malena / haematemesis
Day 6: Doctor, I’ve got this bruise on my back
#1 Using shortcuts / pattern recognitionAlso known as “representativeness bias”
Fitting presentation to known “illness script” Develop hypotheses with incomplete information Often used when working / acting quickly
#2 Confirmation bias#3 Anchoring bias
Attention to data that supports presumed dx Minimise data that contradicts dx
#4 Framing effect#5 Diagnostic momentum
“Transferring patient with pneumonia, ACS and hypotension secondary to GI bleed in context of dual antiplatelets”
Case 2: CT chest request
60 year old man, 80 pack year smoking hx CT chest for F/U lung nodules
83% radiologists missed the gorilla
#6 Search satisfaction
Tendency to stop searching for a diagnosis once you’ve found something
What else could this be?
Slow down and think again
Case 3
18 year old lady admitted at private hospital psychiatry unit for anorexia nervosa
BMI 14 Week 2:
Flu-like symptoms, dry cough, night sweats, fevers
Septic screen
Commenced IV Abx: Amoxycillin / Azithromycin
Systems enquiry: otherwise unremarkable
Day 5-7: Not improving
IV Abx broadened
Meropenem / Lincomycin
Multiple microbiological investigations –ve
Required long course IV Abx on d/c with HITH
3 months later
Sputum MCSAcid-fast bacilli
Direct molecular PCR test: Positive for M. tuberculosis complex
#7: “Common things are common”
When you hear hoof beats, first think horses but consider zebras too.
The next patient
50 year old man, day 5 admission with pneumonia and ongoing fevers despite IV antibiotics…
You ask the physiotherapist to do induced sputums ? AFB
… Your consultant suggests a repeat CXR
Evolving effusion and possible empyema
The next patient
#7 Availability bias
#7 Availability bias
Diagnosis based on what is most available, rather than what is most probable
Stop!
Case 4
56 year old man BIBA with angioedema and ? self-terminating seizure
PMHx: ETOH +++, BPAD, Head injury, no fixed address
Intubated on arrival, ICU o/n Extubated on day 2 Immunology r/v: angioedema likely 2’ry NSAID Discharged to medical ward
“I deserve to be okay”
Day 4: Eating breakfast Perseverant speech Examination otherwise NAD
Reviewed by consultant / team
Delirium: ETOH withdrawal / post-ICU
Benzodiazepines prescribed
“I deserve to be okay”
Later
EEG ordered: focal status epilepticus
MRI: epileptogenic lesion presumed secondary to previous head injury
#8 Attribution errors
Patients fitting a negative stereotype Diagnosis presumed to align with stereotype He deserved to be okay!
Case 5
85 year old Italian lady admitted with nausea, malaise and leg weakness.
+++ Family present at all times
Cont…
Thorough neurological examination Watched by 5 family members, interrupting
constantly, hysterical Pt’s weakness interpreted as give-way
Diagnosis: likely functional
Day 3
Neurology consult
Diagnosis: Gullain Barre syndrome
#9 Negative counter-transference
• Doctors who feel dislike toward patients / family are more likely to:
• Interrupt during recitation of sx
• Lose patience required to consider alternatives
• Fix on a convenient dx
Case 6
Group of 3 ED registrars on a ski trip 28 year old female sustains high velocity fall
with hyperflexion Injury Severe lower cervical neck pain No “neurology” Ongoing significant pain for weeks Continues to ski, surf, work
3 weeks later
X-rays / CT:# C7 (lamina) and T1
spinous processes
#10 Positive countertransference
Positive emotions for the patient can also lead to errors
We focus on the information that aligns with the outcome we want for the patient
Apparent wellness can lead to“dysrationalia override”
Burn out
Exhaustion Impaired thinking Deflection Goal is to “clear the decks” Stop caring for patients
Temptation to work faster, use less effort (system 1)
Navigating safely
What can we do?
Metacognition: stepping back to reflect on the thinking process
The ability to realize which mode (system 1 or 2) you are in and move from one to the other
What doesn’t fit? Could there be something else?What diagnostic labels have been handed over?
Have I have missed another horse or a zebra?
Am I just seeing an “available” diagnosis?
Take extra care when you feel negative (or positive) emotions towards a patient
Are you paying attention?
Experts are able to recognize when patternsdo not fit their previous experience
And shift gears to use system 2 (slow down)
Cognitive check-points / diagnostic time-out
Phone a friend
Consider worst case scenario
Optimise work conditions
Supervision / team work
Clinical environment
Strategies
“If you listen to the patient, he is telling you the diagnosis”
– William Osler
Strategies
Learn from our mistakesAnalyse our own mistakes
Keep a mental (or written) log of mistakes
Build a supportive workplace where we can:Provide feedback
M&M: Analyse cognitive errors (and system errors)
Look after ourselves
Strategies
If I can’t talk about my mistakes:
How can I share with my colleagues?
How can I teach others not to
make the same mistakes?
Can I point out potential errors to my colleagues?
Build a supportive culture
Teaching juniors to drive
Conclusions
1. Misdiagnoses are commonly due to cognitive errors
2. Cognitive errors are commonly due to reliance on “system 1”
3. There are many strategies to avoid diagnostic error (metacognition)
Audience thoughts?