Medical Decision-Making
Keith Bradley, MD
Director
Research Associates Program at St. Vincent’s
National Alliance of RA Programs
Three (3) Modes of Diagnosis
• Pattern Recognition (“Augenblick”)
• Branching
• Matching
Augenblick
“blink of an eye”
See it; know it
ABC’s
• A = asymmetric
• B = border irregular
• C = color black or variable
• D = diameter > 1/4”
Branching
Branching
e.g., Chest Pain
Branching
e.g., Chest Pain
• “expert”
Branching
e.g., Chest Pain
• “expert”
• “blinders”
Branching
e.g., Chest Pain
• “expert”
• “blinders”
potential for error
Branching
e.g., Chest Pain
• “expert”
• “blinders”
potential for error
• “practice”
Matching
Matching
• ALL possible diagnoses on x-axis
Matching
• ALL possible diagnoses on x-axis
• Each possible – symptom
– sign on y-axis
– investigation result
Matching
• ALL possible diagnoses on x-axis
• Each possible sx, px, tx on y-axis
• = Excel spreadsheet
Matching
• ALL possible diagnoses on x-axis
• Each possible diagnoses on y-axis
• = Excel spreadsheet
• Lawrence Weed, MD / “couplers”
Different Types of Problems Different Types of Responses
Non-Traumatic Unconsciousness
Non-Traumatic Unconsciousness
• Airway
Non-Traumatic Unconsciousness
• Airway
• Breathing
Non-Traumatic Unconsciousness
• Airway
• Breathing
• Circulation
Non-Traumatic Unconsciousness
• Airway
• Breathing
• Circulation
• Defibrillate
Types of Problems Types of Responses
Problem Response
Acute Rapid, simple,
memorized
Fever, Ear Pain in a 3 year old
Fever, Ear Pain
Fever, Ear Pain
Fever, Ear Pain
• Dx = acute otitis media
• Tx = depending on timing: nothing or Abs
Types of Problems Types of Responses
Problem Response
Acute Rapid, simple,
memorized
Routine Routine, stylized
“My leg is swollen”
“My leg is swollen”
• What would Dr. House do?
“My leg is swollen”
• What would Dr. House do?
• DDx
“My leg is swollen”
• What would House do?
• DDx
• Key Question … never forget to ask = ?
“My leg is swollen”
• What would House do?
• DDx
• Key Question … never forget to ask
• Be the star!
“My leg is swollen”
• What would House do?
• DDx
• Key Question … never forget to ask
• Be the star! – thick smear … draw blood at night
“My leg is swollen”
• Dx = filiariasis
“My leg is swollen”
• Dx = filiariasis
• Tx = anti-helminths or …
“My leg is swollen”
• Dx = filiariasis• Tx = anti-helminths or …
– The parasites responsible for filariasis have a population of symbiotic bacteria, Wolbachia, that live inside the worm.
– When the symbiotic bacteria are killed by the antibiotic, the worms themselves also die.
• Doxycycline might be effective– Clinical trials in June 2005 by the Liverpool School
of Tropical Medicine reported that an 8 week course almost completely eliminated microfilariaemia.[4][5]
Types of Problems Types of Responses
Problem Response
Acute Rapid, simple,
memorized
Routine Routine, stylized
Unique Unique
MVC, Multiple Trauma
Types of Problems Types of Responses
Problem Response
Acute Rapid, simple, memorized
Routine Routine, stylized
Unique Unique
Complex Complex
