Channeling a Clinician:
Design and Construction of
Clinical Scenarios for
Teaching and Assessment
Eric Niederhoffer
SIU-SOM
Outline
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USMLE style scenario template
Resources for clinical information
Single or multiple disciplines
Discuss example designs
USMLE Style Scenario Template
• A n-year-old (Age) boy/girl/man/woman (Gender) comes/is
brought to the physician/emergency department (Site of Care)
for evaluation of/with a problem (Presenting Complaint including
Duration and Patient/Family History).
• Physical examination shows some combination of pertinent
findings (Height/Weight/BMI/Percentile, Temperature/Heart
Rate/Breathing Rate/Blood Pressure).
• Laboratory studies show some combination of test results
(Reference Ranges provided for non-adult age groups/special
tests).
• Which drug, toxic exposure, diet; predict physical findings, lab
findings, sequelae; identify underlying
cause/mechanism/diagnosis, cause of drug response, drug to
administer (Questions)
Resources for Clinical Information
• Height/weight for children (growth charts)/adults
http://www.babycenter.com/average-fetal-length-weight-chart
http://pediatrics.about.com/cs/growthcharts2/l/bl_ibw_rslts.htm
http://www.cdc.gov/growthcharts/charts.htm
https://www.nhlbi.nih.gov/health/resources/heart/latino-weight-html/need
• Heart/respiration rate, blood pressure for
children
http://www.emedicinehealth.com/pediatric_vital_signs/article_em.htm
• Physical exam/heart/lung sounds
http://www.meddean.luc.edu/lumen/meded/medicine/pulmonar/pd/contents.htm
http://www.med.umich.edu/lrc/psb_open/repo/primer_heartsound/primer_heartsound.html
Reference Ranges
K+
ClHCO3Ca2+
Urea nitrogen
Glucose, fasting
Creatinine
Phosphorus
Total CO2
Total protein
Albumin
Osmolality
Uric acid
Serum
135-147 mEq/L
3.5-5.0 mEq/L
95-105 mEq/L
22-28 mEq/L
8.4-10.2 mg/dL
7-18 mg/dL
70-110 mg/dL
0.6-1.2 mg/dL
3-4.5 mg/dL
24-30 mEq/L
6-7.8 g/dL
3.5-5.5 g/dL
275-295 mOsm/kg water
3-7 mg/dL
Total cholesterol
LDL
HDL
Triglycerides
Lipids
<200 mg/dL
<130 mg/dL
>40 mg/dL
<160 mg/dL
Na+
Arterial Blood Gases
pH
7.35-7.45
Pa.CO2 (PCO2)
33-44 mm Hg
Pa.O2 (PO2)
75-105 mm Hg
HCO3
22-28 mEq/L
O2 saturation
96-100%
+
Anion gap (no K )
8-16 mEq/L
+
with K
12-20 mEq/L
Bicarbonate gap
-6-+6 mEq/L
Blood
Hemoglobin, male
13-16 g/dL
female
12-15 g/dL
Hematocrit, male
42-50%
female
40-48%
O2 binding capacity
1.34 mL O2/g Hb
Creatinine clearance
Osmolality
Specific gravity
Protein
Urine
90-140 mL/min
50-1400 mOsm/kg water
1.003-1.030
<150 mg/24 h
Potential Diseases
Disease
Anemia
Chronic obstructive pulmonary disease
Diabetes
Down syndrome
Gout
Lactase deficiency
Marfan syndrome
5,10-Methylenetetrahydrofolate reductase deficiency
Minimal change disease
Mixed acid-base disorders
Muscular dystrophy
Parkinson disease
Potential Concepts
Concept
Protein/enzyme structure/function in health/disease
DNA structure/function, transcription/translation in
health/disease
Signal transduction mediated cellular responses
Protein/enzyme small molecule interactions in
health/disease
Regulation of metabolic flux
Serum chemistries (anion/bicarbonate gap) as
marker for organ function/disease
Example of Single Discipline Question
A 3430 g (7 lb 9 oz) infant delivered at 42 weeks gestation to a primigravida woman shows a
positive result for newborn screening of hemoglobin disorders. A complete blood count shows:
Hemoglobin
17.0 g/dL
Hematocrit
49%
Mean corpuscular volume
72 fL
Hemoglobin electrophoresis shows 80% HbA, 5% HbA2 and 15% HbF. A defect in which of the
following globin genes is most likely in this patient?
A. Alpha
B. Beta
C. Gamma
D. Delta
E. Epsilon
F.
Zeta
Example of Multiple Discipline Question
A 51-year-old woman with a history of diarrhea poorly controlled with medication comes to the physician for
evaluation of food intolerance. She is 170 cm (5 ft 7 in) tall and weighs 69 kg (152 lb); BMI is 24 kg/m2. Her
temperature is 37.5°C (99.5°F), pulse is 72/min, respirations are 22/min and blood pressure is 120/80 mm Hg. A
complete blood count, serum studies, and hemoglobin electrophoresis show:
Hemoglobin
12.4 g/dL
Albumin
2.8 g/dL
HbA
93%
Hematocrit
37%
CO2 content
22 mmol/L
HbA2
5%
Mean corpuscular volume
72 fL
HbF
2%
Serum iron concentration is within the reference range. All other values are within the reference ranges. A
peripheral blood smear shows microcytosis. Additional laboratory studies show increased concentrations of tissue
transglutaminase–immunoglobulin A and tissue transglutaminase–immunoglobulin G. Which of the following
changes in globin expression is most likely in this patient?
A.
Decreased post-translational modification of zeta globin gene product
B.
Decreased transcription of alpha globin gene
C.
Decreased translation of beta globin gene
D.
Increased post-translational modification of zeta globin gene product
E.
Increased transcription of alpha globin gene
F.
Increased translation of beta globin gene
Let’s Discuss What We Have Designed
• Is the presenting complaint/situation clearly defined?
• Dpes the physical examination data make sense?
• Do the laboratory testing results allow students to exclude differentials
and/or focus on the primary concern (how bad is the condition)?
• Can students understand the problem by using the information or is it
recall?
• How can the scenarios be improved or altered to fit the educational
need (ask for a clinician’s assistance)?