Clinical Reasoning

Your (and my) Goals

Patient care Medical knowledge Interpersonal & communication skills Professionalism Practice-based learning Systems-based practice

But why are you here???

Patient care Medical knowledge Interpersonal & communication skills Professionalism Practice-based learning Systems-based practice

But why are you here???

Learn to make a diagnosis

Assimilate complex clinical information into patient relevant plans

…to become a physician… (it’s more than a title)

Objectives

Understand physicians’ diagnostic reasoning strategy

Identify gaps and barriers to clinical reasoning

Identify strategies for improving clinical decisions

Basic Patient Rights/Bill of Rights

Information for patients Choice of providers and plans Access to emergency services Taking part in treatment decisions Respect and non-discrimination Confidentiality of health information Complaints and appeals Consumer responsibilities

Basic Patient Rights:

Every patient deserves:A diagnosisA treatment plan/optionsAn expected course

Clinical Vignette

Vignette

72 year-old male with dyspnea, nausea PMH: COPD, CAD, CHF (EF 40%), HTN, HLP, CKD, OA Meds:

Lisinopril/HCTZ (Zestoretic) Aspirin (Ecotrin) Atorvastatin (Lipitor) Tiotropium (Spiriva) Fluticasone/salmeterol (Advair)

Allergies: None Social: 1 PPD tobacco use (110 pack years)

Vignette

Exam: HR: 107 RR: 32 Temp: 100.1 BP: 102/62 SpO2: 96% on 2L Pain: 2/10

Why is Clinical Reasoning Difficult?

No absolutes:A + B = CA + B = DC ≠ D

Why is Clinical Reasoning Difficult?

No absolutes:A + B (+/- X) = CA + B (+/- Y) = DC ≠ D

The answer may be evolving or an unknown disease

How I Think…Data Gathering

Problem Identification

Differential

Diagnosis

Treatment

Data Gathering

Problem Identification

-History

-Physical

-Labs

-Studies-Chief complaint

-Discovered problems

-Formulate one sentence summary

Pitfalls:

1. Failure to recognize a problem2. Inability to summarize 2. Patient-directed bias3. Knowledge deficit

Data Gathering

Problem Identification

Differential

Use “Illness Scripts”:

1. Combine symptoms andproblems to get diagnoses 2. Arrange by order of likelihood

Illness Scripts

Knowledge

- Knowledge of diseases

- Understanding of pathophysiology of disease process

- Symptom clusters:

-Ex. Fever + cough + dyspnea = ???

Experience

- Exposure to disease in past

- Reinforcement of clinical patterns

- Familiarity with complex symptom clusters

- Ex. Repeated exposure to heart failure exacerbations

Context- Clinical “situational awareness”

- Co-morbid conditions

Differential Diagnosis

Knowledge

ExperienceContext

- Develop from illness scripts

- Hypothesis formation

- Order by likelihood of disease

- Allows for completeness when scripts are not fully developed

Differential Diagnosis

Knowledge

ExperienceContext

For each potential diagnosis:

- Consider prevalence - Consider risk factors - Consider RISK of disease

22 year-old male smoker with dyspnea:

Knowledge

- Asthma is caused by reversible airway obstruction

- This is treated with beta agonists and corticosteroids

Experience

- Asthma patients usually have significant dyspnea and wheezing on exam

- Patient’s with asthma exacerbation usually respond quickly to therapyContext- The patient fits the profile of a poorly controlled asthmatic

- Pollen counts are very high at this time of year

Differential Diagnosis

Knowledge

ExperienceContext

- “Hypothesis formation” – Patient has asthma exacerbation

-Patient could also have:-Pneumonia-Bronchitis-Sinusitis-Vocal cord dysfunction-Pulmonary embolism-Myocardial infarction

Data Gathering

Problem Identification

Differential

DiagnosisEstablishing the Diagnosis:

1. Perform diagnostic tests and procedures to confirm hypothesis2. Evaluate “Illness Scripts”3. Compare and contrast

Data Gathering

Problem Identification

Differential

Diagnosis

Treatment

Problem Areas

Data Gathering

- Failure to obtain pertinent history

- Lack of medical records

- Failure to perform adequate exam

- Preoccupation with extraneous details

Problem Identification

- Failure to synthesize pertinent items

- Focus on unimportant details

- Missed problems

Problem Areas

- Preoccupation with zebras

- Lack of hypothesis formation

- Difficulty with prioritization

- Bias/Tunnel vision

Differential

Diagnosis

- Fear of commitment

- Misinterpretation of data

- Failure to reassess response to treatment

More Diagnositic Pitfalls

Using a problem as a diagnosisExamples: dyspnea; cough; fever

Using a differential as a diagnosisExample: Headache – could be migraine,

tension, or medication induced…

Several Common Errors

Availability bias:Tendency to judge the likelihood of an event by

the frequency of events (or recent exposure) ?COPD/CHF exacerbation?

Attribution bias:Patient fits a negative stereotype

Chronic pain patient presenting with “10/10” pain

Cognitive Errors

Confirmation bias: Selectively accepting or rejecting information

Make a diagnosis fit regardless of data Often subconscious decisions

Other errors: Personal emotions

Both liking and disliking a patient can affect judgment “Burnout” can affect reasoning “VIP” medicine is bad for all

Back To The Clinical Vignette

Vignette

Exam: HR: 92 RR: 32 Temp: 97.7 BP: 110/62 SpO2: 96% on 2L Pain: 2/10

Differential Diagnosis

Knowledge

ExperienceContext

- “Hypothesis formation” – Patient has ASA toxicity

-Patient could also have:-Pneumonia-COPD exacerbation-CHF exacerbation-Acute MI-Pulmonary embolism-Pneumothorax-Bacteremia

Purpose of Clinical Reasoning

To make a diagnosis

To assimilate complex clinical information into patient relevant plans (quickly and correctly)

…to become a physician… (it’s more than a title)

Resources

Resources

Bowen, Judith. “Educational Strategies to Promote Clinical Diagnostic Reasoning.” NEJM 2006;355:21:2217-25.

Elstein, A. “Clinical problem solving and diagnostic decision making.” BMJ 2002;234:324-32.

Rapezzi, C. “White coats and fingerprints:diagnostic reasoning in medicine and investigative methods of fictional detectives.” BMJ 2005;331:1491-94

Questions?

Other ApproachesName: Case: Date:

PossibleDiagnoses

Biological mechanism (pathophysiology) of disorder that results in symptoms and signs

Risk factors for illness present in patient (or worth asking about)

Other symptoms or physical examination findings that would support the diagnosis

Other information needed to make diagnosis

Factors in history, physical exam, etc., supporting diagnosis

A.

D.

C.

B.

Clinical Vignette

Clinical VignetteData Gathering

Problem Identification

Differential

Diagnosis

Treatment

Acute onset of recurrent, painful, monoarticular

arthritis in an otherwise health male

-Gout-Pseudo-gout-Septic arthritis-Osteoarthritis-Systemic syndrome-Traumatic injury

54 year-old male with sudden onset knee painand swelling, worse withmovement.