Chapter 8 Flashcards
Somatic Effects
All cells in body other than sex cells
Genetic Effects
Effects to radiating sperm and ovum
Timeframe for early effects
Hours, days or weeks
Timeframe for late effects
Months or years
Increased dose =
Increased response
Protracted
Dose delivered continuously over a long period of time at a low dose
Examples of Protracted dose
Brachytherapy and radioactive seeds
Fractionated
Dose that is delivered in equal fractions so cells have time to heal and repair
Example of fractionated dose
Radiation therapy
ARS
Acute radiation syndrome
What are the three possible syndromes
- Hematopoietic Syndrome
- Gastrointestinal Syndrome
- Cerebrovascular Syndrome
What are the four responses to ARS
- Prodromal
- Latent period
- Manifest illness
- Recovery or death
What is the dose for the prodromal stage to start and how long can symptoms last
1 Gy or more
Hours to days
What is latent period and how long are the symptoms
Resting stage
Up to one week
What is the sub lethal and the lethal dose for recovery or death and how long are the effects
Sub lethal 2-3 Gy
Lethal 6-10 Gy
Recovery in 3 months
Dose for Hematopoietic syndrome
1-10 Gy
What is most radiosensitive
Bone marrow
What dose will decrease white blood cells
.35 Gy
What dose will decrease platelets
.5 Gy
What happens with decreased red blood cells
Anemia, low oxygen, organ atrophy
As survival time decreases
Dose increases
Death will occur within __ weeks if whole body dose of __ Gy or higher was received
6-8
2
Recovery will occur within __ weeks to __ months if dose is less than __ Gy received
3
6
2
What are some treatment options
Bone marrow transplant
Blood transfusions
IV support
What is the most radioactive cell white blood cell
Lymphocytes
What dose does gastrointestinal syndrome set in
6-10 Gy
When does death occur within gastrointestinal syndrome
3-10 days
How long is the latent period for gastrointestinal syndrome
5 days
When does cerebrovascular syndrome set in
50 Gy
What is the latent period for cerebrovascular
12 hours
LD
Lethal Dose
50/60
50% of the population will die within 60 days
What is the dose for whole body exposure to low LET radiation
3.2-4.5 Gy
Repair and recovery
Repair enzymes (protein) will activate to repair the radiation damaged tissue when exposed to sub lethal doses of radiation
What can repair and recovery cause
Mutated cells which is a late effect
Oxygenated cells
Repair better
The more doses of radiation
The harder it is to repair the cell
