Nuclear Casualties - Arkansas Hospital Association

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The Nuclear Incident
Management of Nuclear
Casualties
DPT 8.0
Hospital Management of
Nuclear Casualties
DPT 8.0
Terminal Objective
• Be able to describe the various types of radiological
hazards.
• Become familiar with the acute health effects from
radiation contamination and exposure.
• Become familiar with the principles of diagnosis,
treatment and management of radiation casualties.
DPT 8.0
Radiological and Nuclear Devices
CONCEPTUAL
DISPERSAL DEVICE
SHIELDED CONTAINER
RADIOACTIVE
MATERIAL
HIGH
EXPLOSIVE
• Simple radiological
device
• Radiological dispersal
device
• Reactor
• Improvised nuclear
device
• Nuclear weapon
DPT 8.0
The Basics of Radiation
Ionizing radiation is
electromagnetic energy
or energetic particles
emitted from a source.
Ionizing radiation is able
to strip electrons from
atoms causing chemical
changes in molecules.
DPT 8.0
The Basics of Radiation
Chemical
Damage
Free Radicals
10-10 Seconds
Biological
Molecular Damage
Biological
Damage
1. Proteins
2. Membrane
3. DNA
Cells, tissues,
whole animals
Hours to years
Seconds to
hours
DPT 8.0
Ionizing Radiation - Alpha
• 2 neutrons and 2 protons
• Highly ionizing
• Travels several centimeters in air and a few
microns in tissue
• Component of nuclear fallout
• Stopped by a thin paper or clothing
• Threat is inhalation or absorption of alpha
emitter in wounds
DPT 8.0
Ionizing Radiation - Beta
• High energy “electron” emitted from nucleus
• Can have wide range of energies depending
upon the particular radionuclide
• Moderately penetrating
– Up to a few meters in air
– Millimeters in tissue
DPT 8.0
Gamma or X-Ray (Photons)
• High energy rays
• Very penetrating
• Difficult to shield
• Can be produced from radioactive decay and a
nuclear weapon explosion or reactor accident
DPT 8.0
Ionizing Radiation - Neutrons
• Neutral particle emitted from the nucleus
• Can be very penetrating
• Requires special consideration for shielding
DPT 8.0
Examples of Radioactive Materials
Substance
Half Life
Emit
Use
Americium 241
458 years
a, g
Smoke Detectors
Cobalt 60
5.3 years
b, g
Medical Therapy
Plutonium 238
86.4 years
a
Thermoelectric Gen.
Plutonium 239
24,400 yrs
a
Reactors and Weapons
Radium 226
1,602 yrs
a
Medical Therapy
Uranium 238
millions yrs
a, b, g
Reactors and Weapons
Iridium 192
74 days
b, g
Industrial Radiography
DPT 8.0
Radiation Half-Life
• Time required for a radioactive substance to lose half of its
radioactivity
• Each radionuclide has a unique half-life
• Half-lives range from extremely short (fraction of a second)
to millions of years
Examples:
Tc-99m
I-131
Co-60
Sr-90
Pu-239
U-238
6.0 hrs
8.05 days
5.26 yrs
28.1 yrs
24,400 yrs
4,150,000,000 yrs
DPT 8.0
Radiation - Units of Measure
• rad - basic unit for measuring
radiation
• rem - quantifies the amount of
damage that is suspected
from a particular type of
radiation dose
DPT 8.0
Radiation Doses in Perspective
Natural background and manmade radiation
360 mrem / yr
Diagnostic chest x-ray
10 mrem
Flight from LA to Paris
4.8 mrem
Barium enema
800 mrem
Smoking 1.5 ppd
Heart catheterization
16,000 mrem / yr
45,000 mrem
Mild acute radiation sickness
200,000 mrem
LD50 for irradiation
450,000 mrem
mrem = millirem = 1/1000 of a rem
DPT 8.0
Types of Radiation Exposure
• External irradiation - whole-body or partial-body
• Contamination by radioactive materials - external
(deposited on the skin) or internal (inhaled, swallowed,
absorbed through skin, or introduced through wounds)
• Incorporation of radioactive materials - uptake by body
cells, tissues, or organs (bone, liver, kidney, etc)
• Combined radiation injury - combination of the above
complicated by trauma.
DPT 8.0
Radiation Injury - External Irradiation
s



Partial
Local

Body


DPT 8.0
Whole
Body
Radiation Injury - Contamination
External
Internal
DPT 8.0
Radiation Injury - Incorporation
Thyroid
Lung
Liver
Bone
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Radiation - LD50
• We know what radiations are produced
• We know how to measure them
• But the body senses cannot detect radiation.
Therefore, how can we measure the biological
damage?
– LD50/30 Animals
– LD50/60 Human
DPT 8.0
Examples of LD50 for Given Species
Species
Dose (rads)
• Guinea Pigs
250
LD 50/30
• Goat
350
LD 50/30
• Man
250-450
(LD 50/60)
• Mouse
570
LD 50/30
• Rat
550-800
LD 50/30
• Frog
700
LD 50/30
• Snail
8,000-20,000 LD 50/30
DPT 8.0
Severity of Injury
The higher the dose, the more
severe the early effects and the
greater the possibility of delayed
effects
DPT 8.0
Acute Radiation Syndrome (ARS)
• Group of symptoms that develop after total body
irradiation (> 100 rads)
• May occur from either internal or external radiation
• Four important factors are:
– High Dose
– High Dose Rate
– Whole Body Exposure
– Penetrating Radiation
DPT 8.0
ARS - Phases
• Prodromal Phase - occurs in the first 48 to 72 fours postexposure and is characterized by nausea, vomiting, and
anorexia. At doses below about 500 rads last 2 to 4 days.
• Latent Phase - follows the prodromal phase and lasts for
approximately 2 to 2 1/2 weeks. During this time, critical cell
populations (leukocytes, platelets) are decreasing as a
result of bone marrow insult. The time interval decreases as
the dose increases.
• Illness Phase - period when overt illness develops
• Recovery or Death Phase - may take weeks or months
DPT 8.0
ARS - Hematopoitic System
Blood Count
RBC
Cell
Reduction
Neutrophils
Lymphocytes
Platelets
24-hr
1 week
2 weeks
3 weeks
DPT 8.0
Absolute Lymphocytes (109/L)
ARS - Hematopoietic Syndrome
3.0
2.5
Normal Range
2.0
1.5
Moderate
1.0
Severe
Patient
0.5
0.1
0 3 6 17 24
48 hrs
Very Severe
Lethal
DPT 8.0
Injury
ARS - Gastrointestinal Syndrome
• Radiation > 600 rads
• Damages intestinal lining
• Nausea and vomiting within the
first 2 - 4 hours
• May develop diarrhea
• Associated with sepsis and
opportunistic infections
• At 10 days could develop bloody
diarrhea resulting in death
DPT 8.0
ARS - Central Nervous System
• Seen with radiation dose >
1,000 rads
• Microvascular leaks 
edema
• Elevated intracranial
pressure
• Death within hours
DPT 8.0
Response
300
600
Necrosis
Moist
Desquamation
ARS - Skin
1000 >1500 >5000
Dose
DPT 8.0
ARS & Trauma
• Radiation and Trauma =  Mortality
• Trauma is the first priority
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Treatment
• Wound and burn care, surgery, and orthopedic
repair should be done in the first 48 hours or
delayed for 2 to 3 months
Emergency
Surgery
Hemopoietic Recovery
No Surgery
Surgery
Permitted
24 - 48 Hours
3 Months
After 3 Months
DPT 8.0
Survival Time
Survival
Time
Hematopoietic
Gastrointestinal
CNS/
CVS
200 Rads
1000 Rads
100,000 Rads
DPT 8.0
Classification, Treatment & Disposition
• Patients are classified in three categories based
on signs and symptoms:
– Survival probable < 100 rads
– Survival possible 200 - 800 rads
– Survival improbable > 800 rads
DPT 8.0
Classification, Treatment & Disposition
Incorporation / Internal Contamination
• Various medications can be used to limit uptake or
facilitate removal of radioactive material
• Numerous medications are approved by the FDA.
Certain drugs are investigational and can be used in
an emergency (i.e. Radiogardase [Prussian Blue]
and DTPA)
• NCRP 65
DPT 8.0
Radiation Protection Principles
• Time
• Distance
• Shielding
DPT 8.0
Key Points
• No antidote for radiation exposure - treatment is
primarily supportive
• Minimal risk to responding personnel from radiation
contaminated patients
• Early symptoms are an indication of the severity of
the radiation dose
• Consult with specialists for “survivable groups”
• Treat life-threatening injuries first
DPT 8.0
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