Mario Hernandez
University of Nebraska Medical Center - College of Medicine
Omaha, Nebraska
Instructor(s): Von Essen, Susanna; Rhee, Kenneth
Subject area: Health / Medicine
Department: Medicine
Level: Undergraduate Medical
Duration of exercise: 3 sessions, 5 hours total
Learning objective: Develop Group Skills, Develop Individual Skills, Provide Information
Teaching style: Group Activity, In-class Activity
Please note that the copyright for this course project is retained by the instructor.
This Problem Based Learning Case is presented to medical students at the University of Nebraska College of Medicine. The students work through an actual case presentation of an environmental health problem. The instructor guides the discussion as the students work through the case. In an interactive question/discussion format, needed information is provided to the students to work through the differential diagnosis and arrive at the appropriate conclusion. This case focuses on pulmonary edema.
FACILITATOR GUIDE
Major learning issues
1. Acute and chronic pesticide poisoning.
2. The differential diagnosis of vomiting and diarrhea in adults.
3. The pathophysiology of emesis.
4. The pathophysiology of diarrhea.
5. Electrolyte disturbances associated with vomiting and diarrhea
6. Clinical application of plasma and RBC cholinesterase measurements
7. Causitive organisms, symptoms and epidemiology of food-borne infectious diseases.
Minor learning issues
1. The differential diagnosis of vomiting and diarrhea in a child.
2. The pharmacologic management of vomiting and diarrhea.
3. Prevention of pesticide poisoning.
4. Long-term effects of heavy pesticide exposure.
Case Objectives
1. Outline the risks and consequences of acute and chronic pesticide poisoning.
2. Discuss the differential diagnosis of vomiting and diarrhea in adults.
3. State the pathophysiology of vomiting.
4. State the pathophysiology of diarrhea.
5. Outline electrolyte disturbances associated with vomiting and diarrhea.
6. Summarize the treatment of these imbalances.
7. Describe pharmacologic management of vomiting and diarrhea.
8. Discuss the differential diagnosis of vomiting and diarrhea in a child.
9. Develop a differential for acute pulmonary edema in an adult.
10. Discuss the organisms, symptoms, and epidemiology of food-borne infectious diseases.
List of References
1. From the Worker Health and Safety Branch, California Department of Food and Agriculture, Sacramento (Dr. O'Malley), and the Division of Occupational and Environmental Medicine, University of California,, Davis, School of Medicine (Dr. McCurdy).
2. Morgan, D.P. in: Recognition and Management of Pesticide Poisoning, EPA Publication 540/9-88-001, 4th Ed., pp 1-11, 1989
SESSION 1
Initial Presentation
Mr. Hernandez is a 28 year old Hispanic man who comes to your clinic in Madeira County, California complaining of the "stomach flu" just as you are about to close your clinic for the evening. He has been vomiting and having diarrhea for most of the day. He has barely been able to do his work harvesting tomatoes and wants you to give some medication so that he can go back to the field tomorrow
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What other symptoms should you ask him about?
- What are the pathophysiologic mechanisms of vomiting?
- What are the pathophysiologic mechanisms of diarrhea?
- By what pharmacologic mechanisms can these symptoms be treated?
Additional Information
His 2 year old son (who is at home) also has diarrhea. The patient wants you to give him some medication for his little boy.
STOP
END OF SESSION
- What infectious diseases can cause vomiting?
- What infectious diseases can cause diarrhea?
- What infectious diseases can cause both?
- Which ones are likely in a California farm worker?
- How could they have been transmitted?
- What are infectious causes of diarrhea in a child?
- What are noninfectious causes of diarrhea in adults?
- What are noninfectious causes of diarrhea in children?
- Can you assume that the symptoms of the father and son have the same etiology?
- How could you prove or disprove this?
- Is doing so cost-effective?
- Is sending medication home for the child ethically and medically correct?
Wrap-up
Hand out summary of this session.
1. Have a student summarize the case.
2. Review and prioritize learning issues; discuss possible resources.
Review Group Process
1. Did everyone get a chance to participate?
2. Did someone dominate the discussion?
3. Did someone not contribute or participate as fully as they could have?
4. What actions contributed to effective group process?
5. How can we do a better job next time?
Tasks for Next Session
1. Summarize/review case.
2. Review and discuss learning issues.
3. List and critique resources used.
4. Update hypotheses (add, delete, and rank) and inquiry/management decisions.
SESSION 2
Additional History
The patient has felt well until recently. Other symptoms that have been present for several hours include blurred vision and headache. He also is complaining of having excess saliva and that his eyes are watering
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What neural mechanisms could account for his symptoms?
- What farm chemical exposures could account for the patient's symptoms
- What additional questions do you want to ask the patient at this time?
Additional History
His wife, who does field work for another grower, is healthy. The 3 older children are well. The family has not eaten out at any restaurants lately. They buy unpasteurized milk from a neighbor who has a dairy farm. They recently attended a picnic on the weekend at which barbecued pork and hamburgers as well as potato salad were served. He does not think that any of the other party guests got sick.
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What illnesses can be caused by drinking unpasteurized milk?
- What illnesses can be caused by eating uncooked meat or meat that is served at a temperature that is too low?
- What illnesses can be caused by eating unrefrigerated potato salad?
More History
It is early September and Mr. Hernandez has been harvesting grapes for 2 months. He has also been helping another farmer with his turkey growing operation part-time, cleaning the barns. He dislikes the latter job because of the odor in the barns and because it makes him cough.
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What respiratory problems can be associated with exposure to the turkey barn environment?
- Could this explain any of his symptoms?
Office Visit Continues
Past Medical History
Mr. Hernandez was raised in Mexico and came to the United States 5 years ago. He has been healthy all of his life. He had an appendectomy at age 16. He does not smoke cigarettes but does chew smokeless tobacco. He drinks several cans of beer when out with friends.
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What health risks are associated with the use of smokeless tobacco?
- Are there any additional questions you would like to ask Mr. Hernandez?
Family History
His family history is notable for his father having died of unknown causes at age 55. His mother is diabetic and hypertensive.
STOP
END OF SESSION
- Does the past medical history of the parents place the patient at risk for any future medical problems?
- How could this risk be reduced?
Wrap-up
Hand out summary of this session.
1. Have a student summarize the case.
2. Review and prioritize learning issues; discuss possible resources.
Review Group Process
1. Did everyone get a chance to participate?
2. Did someone dominate the discussion?
3. Did someone not contribute or participate as fully as they could have?
4. What actions contributed to effective group process?
5. How can we do a better job next time?
Tasks for Next Session
1. Summarize/review case.
2. Review and discuss learning issues.
3. List and critique resources used.
4. Update hypotheses (add, delete, and rank) and inquiry/management decisions.
SESSION 3
Office Visit Continues
Physical Exam
General: The patient is a robust individual who is diaphoretic and tremulous. He is sitting in a slumped position, blowing his nose frequently.
P = 48 bpm ( normal = 65-85)
BP = 96/70 (normal 120/80)
R = 28
T = 98.8
HEENT exam: Pupils pinpoint, reactive to light. Sclera anicteric. Oral exam notable for dental caries and copious amounts of saliva.
Lungs: Wheezes heard bilaterally. He coughs frothy pink sputum during the exam.
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- Are there any tests that you would like to order at this time?
- What does the frothy pink sputum suggest?
Physical Exam Continues
Heart: No murmurs or gallops
Abdomen: A well healed right lower quadrant scar is present. Soft without rebound tenderness. Mild diffuse tenderness to deep palpation.
Neurologic exam: Remarkable for tremor in both hands and mild weakness of flexor and extensor groups in upper and lower extremities. He cannot stand without assistance.
STOP
DISCUSS THIS SECTION BEFORE YOU CONTINUE
- What is your differential diagnosis at this time?
Office Visit Continues
Suspecting that your patient has pulmonary edema, you order a chest x-ray which confirms you suspicions. SEE EXHIBIT A
Chest x-ray report : PA chest radiograph shows a normal sized heart with evidence of parenchymal consolidation consistent with pulmonary edema. Other diagnostic considerations include infection, over hydration , pulmonary hemorrhage. Correlation with clinical findings is recommended.
STOP
END OF CASE
- How should this problem be treated?
- What is your differential diagnosis at this time?
- How do you determine if occupational exposure to farm chemicals has placed the patient at risk for acute illness?
- What are long term risks associated with exposure to farm chemicals?
- What advice would you give to this patient?
- What are you going to do about his sonÿs symptoms?
- If you suspect a food borne pathogen, what is your responsibility as the physician?
- Who should you notify?
This document was last modified on 06/14/2000 03:08:03 PM
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