TITLE OF LESSON/MODULE
POISONING
MEDICAL MINUTES: DIAGNOSING AND TREATING SALICYLATE
AUTHOR(S) AND SCHOOL AFFILIATION(S)
TONYA NKHATA, LAKOTA WEST FRESHMAN CAMPUS
OVERVIEW
One of the cases that I was able to follow at West Chester Hospital involved a woman who had
come in with altered mental state. I observed the staff of the emergency department as they
figured out what she had by following their normal procedures. It turns out that she had
overdosed on aspirin and they were attempting to stabilize her condition. The following day, I
was able to follow up and see that she was in the ICU and they were battling to keep her
kidneys and liver from shutting down. I thought this case could be presented in such a way that
students could try to follow similar steps and come to the same conclusion that the aspirin
caused her blood to become acidic and it needed to be reversed. The side implications about
overdose and that all medicines are chemicals that react with cells will come up and addressed
in class discussions. Students, in collaborative groups, will have to read and interpret parts of a
journal article, keep a log of what their group decided to do (in which order), and will
(hopefully) provide a plan of treatment for the patient.
TYPE/LEVEL OF INQUIRY 3 – GUIDED INQUIRY
GRADE LEVEL/COURSE 9-12
ANTICIPATED LENGTH OF LESSON/MODULE (MINUTES)
PREREQUISITE KNOWLEDGE



Basic problem solving skills
Knowledge of the pH scale
Understanding that acids are neutralized by bases
STATE/NATIONAL STANDARDS
Science
Course: Biology
2 DAYS, ABOUT 80 MINUTES
Course Content:
Interactions of Matter
• Chemical reactions
Types of reactions
Kinetics
Energy
Equilibrium
Acids/bases
Content Elaboration:
Properties of acids and bases and the ranges of the pH scale were introduced in middle school. In
chemistry, the structural features of molecules are explored to further understand acids and bases. Acids
often result when hydrogen is covalently bonded to an electronegative element and is easily dissociated
from the rest of the molecule to bind with water to form a hydronium ion (H 3O+). The acidity of an aqueous
solution can be expressed as pH, where pH can be calculated from the concentration of the hydronium
ion. Bases are likely to dissociate in water to form a hydroxide ion. Acids can react with bases to form a
salt and water. Such neutralization reactions can be studied quantitatively by performing titration
experiments. Detailed instruction about the equilibrium of acids and bases and the concept of BrønstedLowry and Lewis acids and bases will not be assessed at this level.
MATERIALS NEEDED PER GROUP



Computer with Internet access
Pre printed cards that have Ask the…(doctor, nurse, family, etc) see attachment
Group size: 4 (roughly recorder, researcher, responder, leader roles though not named
as such in this lesson)
INSTRUCTIONAL PLAN (INCLUDE STUDENT SHEETS SEPARATE FROM THIS DOCUMENT.)
Note: I will be incorporating the science behind the various hospital departments that I observed
throughout the year. For example, we will look at red blood cell smears when we do cells—and also
note that if white blood cell counts are higher they can indicate infection. When we talk about isotopes,
I will tell them about other parts of radiology. I think this patient case lends itself to acids and bases
because it is a real life example of what happens when the balance is thrown off. The final “medical
minute” will come at the end of the year when I show and talk about the davinci robotic surgery when
students are dissecting. I believe that they will already have done a couple of these medical minutes
before we get to this one, so they will be familiar with my job shadow experience at West Chester
Hospital.
A. Introduction
I have not done this before so this will be a work in progress, but I envision starting this before
we do anything with acids and bases, as an introduction. We will not have even reviewed their
prior knowledge from junior high school. It should also be noted that I have simplified this a
great deal. I will show them the 30+ pages of reports that were generated in less than 24 hours.
You could ask if they’ve been to the ER before and what kinds of things they’ve seen while there
to generate interest.
B.
Activity
The students will get handout 1, their Log Sheet, and a stack of note cards that are labeled on
one side with the actions that they can take. When they decide on an action, they will bring it to
the teacher and then receive the corresponding card with the information that they need. In
the second attachment I have provided the most basic cards and answers that would be
necessary. At some point, a group will realize that they need to research aspirin poisoning or
salicylate overdose. This link is fairly clear about what happens when someone overdoses on
aspirin and I will give them this web address or an actual hard copy of the article.
http://www.pediatrics.emory.edu/pem/public/documents/97838.pdf
I think that the first time I will have several copies that are appropriately highlighted or marked
with the paragraphs that are most important. From this article they should be able to find that
the treatment is alkalinizing the blood by infusing sodium bicarbonate.
The role of the teacher is mainly facilitator. I will have to see and hear their logic to determine
what information they will need to get next. The “correct” order that was used by the ER staff is
the order that the cards are in on the attachment.
1. Interviews of patient and family
2. Physical exam and blood work
3. Based on those results, they saw that her blood was acidic and she was treated with
sodium bicarbonate.
4. She continued to get worse due to the time it takes for the aspirin to enter the
blood stream and was admitted to the ICU. The following day, she was in the ICU in
critical condition with risk of renal failure and the need to have dialysis to further
remove the salicylate. They were checking blood work every 2 hours.
Ideally her condition could dramatically improve and she could be discharged within a few days,
but she also had other complicating factors which put her at higher risk for complications. I do
not know the final outcome.
Within this lesson, I would expect that students will want to research some other things and I
will let them within reason, but hope that they will realize that the danger is in the aspirin
poisoning. Once most groups have gotten to the article, they will have to spend some time to
figure out the treatment. I want them to understand what it means to read a journal article too!
As they get finished they will start on the next activity in order to allow other groups to get
finished. It is a web activity about acids and bases, but is not directly related to the job shadow.
I have included it as an attachment.
C. Post activity Discussion
I will allow for a class-led discussion of what happened, and eventually fill in the details as I
know them. I think that students will recognize the danger of this type of OD and will naturally
segue into a discussion of other types of drugs. I hope they will then recognize that all drugs are
chemicals that interact with cells and other chemicals to cause effects—both wanted and
unwanted. I will wrap up with a review of what they already know about acids and bases and
the pH scale.
EXTENSIONS
There are many ways to extend this lesson. For more advanced groups, you can give them
“complications” that would need more research and treatment. You could avoid giving them an article
about treatment, and they would have to find one on their own. You could turn it into a competition
and assign points for “correct” decisions and deduct points for random guesses or poor decisions.
ASSESSMENT
The first time around, I will evaluate by participation within the group. They will be graded on
the following internet activity about acids and bases
REFERENCES
I have all of the original documents provided by West Chester Hospital. If anyone would like the
source material, please contact me at tonya.nkhata@lakotaonline.com and I can scan them and e-mail
them.
SAFETY CONSIDERATIONS
I will keep in mind that some students may have home situations that involve drug and alcohol abuse.
Name _______________________ Class
_____________________ Date ____________
Biochemistry Web Activity
In this exercise you will explore some of the
compounds found in all living things.
I.
Text
W formula of water
a
t
e
r
htt
p:/
/www.johnkyrk.com/H2O.html
Most organisms are over _________
percent water
What happens to molecules as the
temperature increases?
Biology
_____________________
The formula for a hydroxyl ion is
___________ and it has a ___________
charge.
The formula for a hydronium ion is
___________ and it has a ___________
charge.
In pure water the number of hydronium
ions _____________ hydroxide ions.
Water is good at dissolving substances that
_______________
Excess Hydrogen ions means
_____________
By _____________ electrons both
oxygen and hydrogen complete their
outer shell. The result is a
______________ bond.
Why do water molecules attract one
another?
________________________________
Cellular processes usually take place in what
pH range? ______________________
The line above represents the pH scale.
Label the acidic and basic ranges, neutral,
and an example of a very strong base and a
very strong acid. Also label the location of
the pH values of the following: digestive
juices, windex, bananas, Clorox, and
ammonia. Include the name and the pH
value.
Ask the PATIENT
Patient is partially aware and will
wake up to loud or painful
stimuli. When she speaks often
curses at staff.
Ask the FAMILY
Patient is 57 with history of chronic
breathing problems. She has been abusing
alcohol for 3 days but do not know when
she had her last drink. They have not seen
seizure activity, but they state “she will sit
there with her eyes open but it is like
nobody is home.” She is slurring her words
and has not been up and walking around.
Her loud “snoring respirations” made them
concerned that she is not breathing
correctly. They are also concerned that she
may have taken some pills.
ACTION: PHYSICAL EXAM
All general physical systems are
normal except the following:
Blood pressure is low—105/41
Respiratory Rate is low—20 breaths
per minute
EKG shows normal heart rhythm
ACTION: HEAD CT (CAT SCAN)
Results are normal
ACTION: DRAW BLOOD and do
tests to check liver and kidney
function, check for drugs and
alcohol
Alcohol negative
Aspirin level very high (salicylate)
Other drugs negative
Kidneys and liver show some abnormalities,
but are functioning at this time.
Blood pH is 7.23, normal is between 7.35
and 7.45
Research: ____________________
You fill in what you’d like to look up online.
Research: ____________________
You fill in what you’d like to look up online.
Research: ____________________
You fill in what you’d like to look up online.
(use judgment about requests, most will be accepted even if not helpful) When they say salicylate or aspirin poising
direct them to http://www.pediatrics.emory.edu/pem/public/documents/97838.pdf
I will have highlighted copies to help groups that will struggle to find the important info—may be used for all of them the
first time around.
(use judgment about requests, most will be accepted even if not helpful) When they say salicylate or aspirin poising
direct them to http://www.pediatrics.emory.edu/pem/public/documents/97838.pdf
I will have highlighted copies to help groups that will struggle to find the important info—may be used for all of them the
first time around.
(use judgment about requests, most will be accepted even if not helpful) When they say salicylate or aspirin poising
direct them to http://www.pediatrics.emory.edu/pem/public/documents/97838.pdf
I will have highlighted copies to help groups that will struggle to find the important info—may be used for all of them the
first time around.
Treatment: ________________________
(options may include repeat blood work, give medication (be specific), send to
surgery, discharge, admit to hospital, etc.
Treatment: ________________________
(options may include repeat blood work, give medication (be specific), send to
surgery, discharge, admit to hospital, etc.
Treatment: ________________________
(options may include repeat blood work, give medication (be specific), send to
surgery, discharge, admit to hospital, etc.
Looking for treatments as outlined in the article on salicylate poisoning. (iv dextrose, sodium
bicarbonate) They should justify their choice by showing you their evidence.
Other treatments will either have no effect, or the patient is worsening, with more kidney
damage, loss of consciousness, or even death.
If they repeat blood work after appropriate treatment, then they will be given improved
results.
Poor treatment choice: Patient is more hypotensive with bp 80s/30.
Poor treatment choice: Serum pH is increasing
Poor treatment choice: Patient combative and needs restraints.
Poor treatment choice: Patient is unconscious.
Good treatment choice: Urine pH is increasing
Good treatment choice: Serum pH is increasing
Good treatment choice: Patient mental status has improved.
Medical Minute: Altered Mental State
Group Names: __________________________
_________________________
You should have a stack of cards that describe the options that you have to assess the patient that has come into the
emergency room. Your teacher has all the information necessary for you to diagnose and treat your patient. However,
you must use your problem solving skills to decide when each step needs to take place, or if it even applies in this case.
Some of the cards will not be used and if you try to use them you would be wasting valuable time! Your goal is to
discharge a healthy patient!
LOG: Here, you are to record what you did and what you learned from it.
What did you do?
What did you learn or evidence did you gather?
What did you do?
What did you learn or
evidence did you gather?
Patient summary: In one good paragraph,
explain what happened to the patient and what
had to be done to treat and release her.