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 diagnosis  A treatment plan/options  An 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:  BP: 102/62  SpO2: 96% on 2L  Pain: 2/10

Why is Clinical Reasoning Difficult? No absolutes:  A + B = C  A + B = D  C ≠ D

Why is Clinical Reasoning Difficult? No absolutes:  A + B (+/- X) = C  A + B (+/- Y) = D  C ≠ 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 problem 2.Inability to summarize 2. Patient-directed bias 3. Knowledge deficit

Data Gathering Problem Identification Differential Use “Illness Scripts”: 1. Combine symptoms and problems 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 Experience Context - Develop from illness scripts - Hypothesis formation - Order by likelihood of disease - Allows for completeness when scripts are not fully developed

Differential Diagnosis Knowledge Experience Context 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 therapy Context - The patient fits the profile of a poorly controlled asthmatic - Pollen counts are very high at this time of year

Differential Diagnosis Knowledge Experience Context - “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 Diagnosis Establishing the Diagnosis: 1.Perform diagnostic tests and procedures to confirm hypothesis 2.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 diagnosis  Examples: dyspnea; cough; fever Using a differential as a diagnosis  Example: 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 Experience Context - “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

Bowen, Judith. “Educational Strategies to Promote Clinical Diagnostic Reasoning.” NEJM 2006;355:21: Elstein, A. “Clinical problem solving and diagnostic decision making.” BMJ 2002;234: Rapezzi, C. “White coats and fingerprints:diagnostic reasoning in medicine and investigative methods of fictional detectives.” BMJ 2005;331:

Questions?

Other Approaches Name:Case:Date: Possible Diagnoses 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

Data 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 pain and swelling, worse with movement.