19: Whole Body Radiation Effects

Whole body radiation effects are typically seen in what situations?

atomic bomb or nuclear accident survivors

two types if whole body radiation effects?

1. somatic

2. genetic

term. Somatic (effects)

def. effects that occur during a person’s lifetime

term. Genetic (effects)

def. effects on future generations

give example of genetic effects

If someone’s gonads get irradiated, and then they have a spontaneous abortion, or a baby with genetic defects

Whole body radiation effects, can be _____ effects or_____ effects

stochastic

non-stochastic

term. stochastic effects

def. effects that have no threshold dose

FYI: they are binary. Either you get them or you don’t

Typical Stochastic effects

1. carcinogenesis

2. genetic mutations

term. Non-stochastic effects

def. somatic effects that increase in severity with an increase in dose

(↑ dose = ↑ severity)

Examples of non-stochastic effects

Most effects:

1. erythema

2. epilation

3. dry mouth

4. etc

term. mean survival time

def. the average time between exposure and death

E,g, There are 2 people exposed to nuclear radiation. The first person dies within 10 days of being exposed. And the second person dies within 20 days of being exposed. What is the mean survival time?

(20+10)/ 2 = 15

True or False: Whole Body Effects of radiation can be either acute or chronic

True

term. acute

def. short time period; within a few weeks of the exposure or less

term. LD 50/30

def. the lethal dose to 50% of the population within 30 days

LD 50/30 aka

LD 50

Dose for LD 50/30 (for whole body)

400cGy

FYI: avg. 300-500 for whole body

minimum observed whole body dose for death

100cGy

maximum observed whole body dose ever survived

850cGy

3 Acute Radiation Syndromes (whole body) aka

Manifest Syndrome

What are the 3 acute radiation syndromes (aka manifest syndromes)

1. Hematologic

2. GI

3. CNS

affecting 3 of the 10 body systems

term. Syndrome

def. A series of syndrome

In addition to the Manifest Syndromes, what are 2 other stages related to these syndromes that typically occur with each person that has received a large whole body dose exposure

1. Prodromal Syndrome

2. Latent Period

term. Prodromal Syndrome

def. the immediate radiation sickness following a large whole body exposure.

Prodromal Syndrome happens in doses in excess of _____cGy

50

Prodromal Syndrome examples

1. hair loss

2. NV

3. Diarrhea

4. Skin Reddening

5. Low Blood Counts

term. Latent Period

def. the period FOLLOWING the prodromal syndrome during which there is NO sign of sickness

The length of the prodromal & latent periods exhibit a (direct/ inverse) relationship with dose

inverse

↓ Dose = ↑ length Prodromal/Latent Periods

What are the dose ranges for the 3 Manifest Sydromes

1. Hematologic Syndrome……..……100-1000cGy

2. GI Syndrome……………………….1000-5000cGy

3. CNS Syndrome……………………..>5000cGy

Which of the Manifest Syndromes, is the one that is potentially curable and why?

Hematologic, cuz the avg. whole body lethal dose is 400cGy and the highest survived dose was 850cGy, and hematologic dose range is 100-1000cGY

Description of Hematologic Syndrome

the Prodromal & Latent periods can each last for weeks

Description of GI Syndrome

Shorter Prodromal & Latent periods; usually just a few days long each

Description of CNS Syndrome

short prodromal & latent period IF AT THERE EVEN IS ONE

Cause of death for the following Syndromes

1. Hematologic: massive infection (WBC)

2. GI: fluid and electrolyte loss (NV & Diarrhea)

3. CNS: Patients die within a FEW HOURS due to intercranial pressure ( confusion, convulsion, NV, vision loss