BASIC LIFE SUPPORT AND HAZARDOUS MATERIALS RESPONSE
UNIT 7:
RESPIRATORY
TOXICOLOGY
OBJECTIVES
The students will be able to:
1.
Given a list of alternatives and working individually, identify
a.
The correct definitions for three types of toxicologic harm that
can affect the respiratory system.
b.
Two symptoms each for three levels of exposure to carbon
monoxide.
c.
Four types of pathophysiology and four treatment procedures
for pulmonary injury.
d.
Four presentation characteristics
procedures for methemoglobinemia.
and
four
treatment
e.
Three pathophysiological effects and
procedures for reduced oxygen levels.
four
treatment
f.
Three pathophysiological effects
procedures for irritant gases.
three
treatment
and
2.
Working in small groups and using a scenario, identify problems,
safety concerns, patient care concerns, and appropriate levels of
personal protective equipment (PPE) for the incident.
3.
Working in small groups and using a scenario, analyze the medical
data available and recommend suitable treatment.
RESPIRATORY TOXICOLOGY
POINTS FOR THE INSTRUCTOR
Many chemicals cause harm to the respiratory tract. Oxygen represents the most
frequently successful treatment. Injury can be presented in a number of
different ways. This unit requires students to read sections of their Student
Manual, discuss key points with their group, add their own experiences and
information to the Student Manual materials, and make a presentation to the
class.
ATTITUDES TO FOSTER
Responders must protect themselves from respiratory injury while assessing and
treating victims.
METHODOLOGY
This unit uses lecture, student readings and presentation, and a small group
activity.
(Total Time: 2 hr., 35 min.)
125 min.
30 min.
Lecture
Objectives
Basic Concepts
Small Group Activity 7.1
High School Incident
HANDOUT
Handout 7-1: Scenario
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RESPIRATORY TOXICOLOGY
125 min.
Lecture
I.
OBJECTIVES (5 min.)
The students will be able to:
A.
Given a list of alternatives and working
individually, identify
1.
The correct definitions for three types of
toxicologic harm that can affect the
respiratory system.
2.
Two symptoms each for three levels of
exposure to carbon monoxide.
3.
Four types of pathophysiology and four
treatment procedures for pulmonary injury.
4.
Four presentation characteristics and four
treatment procedures for
methemoglobinemia.
5.
Three pathophysiological effects and four
treatment procedures for reduced oxygen
levels.
6.
Three pathophysiological effects and three
treatment procedures for irritant gases.
B.
Working in small groups and using a scenario,
identify problems, safety concerns, patient care
concerns, and appropriate levels of personal
protective equipment (PPE) for the incident.
C.
Working in small groups and using a scenario,
analyze the medical data available and recommend
suitable treatment.
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RESPIRATORY TOXICOLOGY
II.
BASIC CONCEPTS (120 min.)
Because of the technical nature of this material, this unit is
presented in a self-study format. The class is divided into
four groups to cover the materials. Each group summarizes
the key points in its section and reports to the entire class.
Prior to the small group work, the instructor covers the
information in subsections A, B, C, and D of Section II Basic
Concepts.
A.
The lungs are the only organ with vital functional
elements in constant contact with the environment.
B.
Lungs have the largest exposed surface area of any
organ.
1.
The lungs have 70 to 100 square meters
constantly in contact with external
environment.
2.
The skin is about two square meters.
3.
The G.I. tract is about ten square meters.
Stress for the students the guideline that there is no smoking,
eating, or drinking at hazardous materials scenes.
Emphasize that because of the respiratory system and the
chance for internal contamination, there are compelling
reasons why one should not smoke if contaminated or in a
contaminated area.
If a bit of humor is needed, make it a no smoking, eating,
drinking, or flash photography rule.
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RESPIRATORY TOXICOLOGY
C.
D.
Respiratory tract is divided into three regions.
1.
Nasopharyngeal section.
2.
Tracheobronchial area.
3.
Pulmonary acinus part.
a.
Respiratory bronchioles.
b.
Alveoli (about 100 million).
Inhaled particles settle according to diameter.
1.
5 to 30 microns--nasopharyngeal.
2.
One to five microns--tracheobronchial.
3.
Less than one micron--alveoli.
Assign the following sections to the groups. If you have
more than four groups, the remaining one or two groups can
cover the same materials as two of the other groups. This
will assure a more comprehensive coverage.
SM p. 7-9
SM p. 7-11
SM p. 7-11
SM p. 7-12
Easel Pad





Group I:
Group II:
Group III:
Group IV:
Agents of Harm and Respiratory Injuries
at Fire Scenes
Other Fire Scene Concerns
Asphyxiatin Injury
Irritant Gases
Each group summarizes three things for its section on an
easel pad or newsprint:



the pathophysiology;
the symptoms; and
the anticipated treatments.
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RESPIRATORY TOXICOLOGY
Each group then reports to the entire class.
The following outline is for instructor use to verify that the
presentations of the groups cover the essential information.
After the groups have reported, touch on some of the key
points in the outline below that you feel need to be stressed or
clarified.
Afterward, proceed to Activity 7.1.
E.
F.
Many chemicals cause harm in the respiratory tract
and are classified by type of harm.
1.
Asphyxiants.
2.
Irritants.
3.
Necrotics.
4.
Fibrotics.
5.
Allergens.
6.
Carcinogens.
7.
No harm to lung, but systemic effects use
the lungs as a pathway to bloodstream and
other target organs.
Respiratory injury at fire scenes.
1.
2.
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Carbon monoxide is a product at most fires.
a.
Pyrolysis.
b.
Overhaul.
Sources.
a.
Organic materials.
b.
Wood.
RESPIRATORY TOXICOLOGY
3.
c.
Paper.
d.
Synthetics.
e.
Household furnishings.
Pathophysiology.
a.
Carboxyhemoglobin.
b.
Decreased oxyhemoglobin.
c.
Hemoglobin preferentially binds
with CO.
d.
Methemoglobinemia.
- Oxyhemoglobin to methemoglobin.
- Decreased oxygen delivery.
- Increased tissue hypoxia.
- Treatment.
-- ABCs.
-- Oxygenation.
-- Decontamination.
-- IV one-percent solution
methylene blue one to two
mg/kg; inject very slowly.
4.
Mild exposure: 20 to 30 percent saturation.
a.
Headache.
b.
Nausea.
c.
Dizziness.
d.
Tachycardia.
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RESPIRATORY TOXICOLOGY
5.
6.
7.
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Moderate exposure: 30 to 50 percent.
a.
Syncope.
b.
Dyspnea.
Severe exposure: over 50 percent.
a.
Seizures.
b.
Coma.
c.
Death.
Other associated symptoms.
a.
Arrhythmias.
b.
Chest pain.
c.
Tachypnea.
d.
Slow, irregular respirations.
e.
Possible pulmonary edema from
injury.
f.
Tinnitus.
g.
Hallucinations.
h.
Confusion.
i.
Visual disturbances.
j.
Impaired judgment.
k.
Loss of memory.
l.
Nausea, vomiting.
m.
Cyanosis, pallor, cherry red skin.
8.
Pregnant patients at increased risk.
9.
Exercise may speed symptomology.
RESPIRATORY TOXICOLOGY
10.
Expected dose response.
a.
100 ppm, no symptoms.
b.
200 ppm, mild headache.
c.
800 ppm, unconsciousness after 2
hours.
d.
6,400 ppm, headache; dizziness in 1
minute.
e.
12,800 ppm, immediate
unconsciousness; danger of death in
1 to 2 minutes.
11.
Beware of delayed effects.
12.
Uneventful convalescence from severe
exposure may manifest up to three weeks
later.
13.
At one percent concentration of CO,
firefighter may be too impaired to safely exit
area.
14.
Treatment.
15.
a.
ABCs.
b.
100 percent oxygen (competitive
inhibition reduces half life).
c.
Hyperbaric chamber.
d.
Be alert for cardiac complications.
Carbon monoxide half-life.
a.
Room air four to six hours.
b.
100 percent oxygen 60 to 90
minutes.
c.
Hyperbaric chamber 20 to 30
minutes.
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RESPIRATORY TOXICOLOGY
G.
Pulmonary injury.
1.
Flame.
2.
Superheated gases.
3.
Steam.
4.
Corrosive effects of inhaled fire gases.
5.
Pathophysiology.
6.
7.
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a.
Edema.
b.
Ciliary paralysis.
c.
Bronchospasm.
d.
Tissue sloughing.
e.
Acid formation.
f.
Surfactant loss.
Presentation.
a.
Arrhythmias.
b.
Headache, dizziness, central nervous
system depression.
c.
Coughing, rhinorrhea, burns to
mucous surfaces, irritation of
mucous surfaces.
d.
Shortness of breath, cyanosis, other
signs of hypoxia.
Treatment.
a.
Airway maintenance.
b.
Suctioning.
c.
Support of ventilations.
RESPIRATORY TOXICOLOGY
d.
8.
9.
Oxygenation.
Be alert for manifestations of poisoning
from other products of combustion.
a.
Sulfur compounds.
b.
Hydrogen sulfide.
c.
Sulfur dioxide.
d.
Nitrogen compounds.
e.
Acid gases.
f.
Acetaldehyde.
g.
Acetic acid.
h.
Formaldehyde.
i.
Formic acid.
j.
Acrolein.
k.
Ammonia.
l.
Hydrogen cyanide.
m.
Phosgene.
n.
Hydrogen fluoride.
Any significant exposure to smoke should
be evaluated at E.D.
a.
Possibility of delayed onset.
b.
Chronic manifestations need
documentation.
Pulseoxymeters measure product saturation in the blood. Do
not assume a high O2 saturation because the meter is reading
high. The high reading may result from a toxic product such
as CO which is saturating the red blood cells.
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RESPIRATORY TOXICOLOGY
H.
Asphyxiation injury.
1.
2.
3.
I.
a.
Combustion consumes oxygen.
b.
Slow oxidation occurs (confined
space).
c.
Oxygen displacement occurs.
Physiological effects of reduced oxygen.
a.
Twenty-one percent oxygen--none.
b.
Seventeen percent oxygen--slight
impairment of coordination, increased
respiratory rate.
c.
Twelve percent oxygen--dizziness,
headache, rapid fatigue.
d.
Nine percent oxygen-unconsciousness.
e.
Six percent oxygen--death within
minutes.
Treatment.
a.
Oxygenation.
b.
Ventilatory support.
c.
Airway management.
d.
ALS as indicated, seizure control,
etc.
Irritant gases.
1.
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Oxygen-deficient atmosphere may result
under certain conditions.
Ubiquitous.
a.
Chlorine.
b.
Ammonia.
RESPIRATORY TOXICOLOGY
2.
3.
4.
c.
Sulfur dioxide.
d.
Phosgene.
e.
Oxides of nitrogen.
Pathophysiology.
a.
Highly soluble--chlorine, ammonia,
sulfur dioxide.
b.
Severe respiratory irritation.
c.
Hydrochloric acid in lungs.
d.
Fluid build-up.
e.
Skin, eye irritation.
f.
May be self-limiting.
Presentation.
a.
Ventricular arrhythmias,
cardiovascular collapse.
b.
Noncardiogenic pulmonary edema,
dyspnea, tachypnea, cough,
rhinorrhea.
c.
Headache, dizziness, central nervous
system depression, coma.
d.
Nausea, vomiting.
e.
Lacrimation, burn to eyes.
f.
Chemical burns to skin.
g.
May be delayed, olfactory fatigue.
h.
Stridor.
Treatment.
a.
Airway, ventilatory support.
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RESPIRATORY TOXICOLOGY
b.
Irrigation of eyes.
c.
Bronchodilators.
Introduction to the High School Scenario
With this unit begins a four-part scenario consisting of an
escalating incident at a local high school. While each
scenario part presents a limited amount of information, the
intent is to not limit you or the students in the management of
the unfolding incident. However, you must exercise care to
keep the activities focused on the desired outcomes and
recommended answers.
You will find additional background information in this
Instructor Guide for each part of the scenario. Do not
divulge this additional information unless students ask for
it. Part of the dynamic of this series of activities is to see if
the students can make proper decisions on the information
they receive or if they need more information to make better
informed decisions.
Once you have revealed all the additional background
information, you need to answer further questions with the
response, "We do not have any further information." Do not
make up additional information. This could compromise
the benefit of the activity.
The responses throughout the four parts are predicated on
hazardous materials training to the Awareness Level.
It is important to guide the class through the stages of the
scenario. The aim is to have the students deal with each level
but, as the next part of the scenario is introduced, have them
move on to consider the new information and its implications.
The students do not have the scenario information
in their manuals. They do, however, have the worksheets.
Therefore, you need to make enough copies of the scenarios
so that each student receives a copy.
Distribute the scenario (handout) at the start of each activity.
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RESPIRATORY TOXICOLOGY
30 min.
Small Group
Activity 7.1
Activity 7.1
High School Incident
Purpose
To identify the real concerns, problems, and response
associated with a simulated incident in a high school.
Directions to Students
SM p. 7-3
1.
The students will work in small groups.
2.
Distribute Handout 7-1.
3.
Clarify the information as needed and then have the
students answer the questions on the worksheet.
4.
After no more than 10 minutes, solicit answers for
the questions.
5.
Go from group to group until all questions have
been answered. Avoid repetition.
6.
Keep the discussion focused on current actions and
future possibilities.
7.
The suggested responses can be found on the
following Student Activity Worksheet.
Handout 7-1
IG p. 7-17
Summary
Summarize briefly by pointing out that this is the first step
in the thoughtful process of analysis and decisionmaking
required at hazardous materials incidents.
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RESPIRATORY TOXICOLOGY
Provide this additional information only if asked.
Smithville High is a medium-size high school of about 825 students. It is a Thursday in late May. The
day is bright and warm. The temperature is already 70°F. The relative humidity is 40 percent. There
is a light, variable wind from the south.
The two persons the first responders find in the nurse's office had just spent 15 minutes in the
Teachers' Lounge. They were alone.
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RESPIRATORY TOXICOLOGY
STUDENT ACTIVITY WORKSHEET
Activity 7.1
High School Incident
Purpose
To identify the real concerns, problems, and response associated with a simulated incident in a high
school.
Directions
1.
Work in small groups.
2.
Using the scenario information provided in Handout 7-1 and referring to the floor plan of the
high school on the next page, answer the questions on the Worksheet.
3.
You will have no more than 10 minutes.
Suggested responses:

High flow of oxygen via a nonrebreather mask

Place the patients in positions of comfort

Transport to an appropriate medical facility
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STUDENT ACTIVITY WORKSHEET
Activity 7.1 (cont'd)
Floor Plan
Exit
Exit
Office
Office
Nurse's
Office
Chemistry
Lab
Biology
Lab
Teachers'
Lounge
Girls'
Restroom
Boys'
Restroom
Exit
Auto
Mechanic
Shop
Overhead
Door
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STUDENT ACTIVITY WORKSHEET
Activity 7.1 (cont'd)
Worksheet
What problems do you see?
What safety concerns do you have for the emergency medical responders?
What are your patient care concerns?
What are the symptoms?
How long have the victims been displaying the symptoms?
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RESPIRATORY TOXICOLOGY
STUDENT ACTIVITY WORKSHEET
Where were the victims prior to arriving at the nurse's station?
How long had they been at the previous location?
Was anything unusual there?
To what does it appear they have been exposed?
What would seem to be an acceptable treatment?
What is the appropriate level of hazardous materials response?
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RESPIRATORY TOXICOLOGY
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