ARRT Boards review (Patient Care) (radiation safety)

Patient Rights

-Consent (Informed, verbal, implied, and written)

- confidentiality (HIPPA)

- Patients Bill of Rights (DNR, Living will, health care proxy, advanced directives, research participation)

Battery

intentional and unathorized acts (ex. performing an exam a patient refused)

Negligence

Failure to exercise reasonable care, causing injury or damage ( Ex: failure to lock a wheelchair and pt. falls)

Malpractice

professional negligence when a professional deviates from accepted standards of care

Tort: (2 types: intentional and unintentional)

intentional: assault, battery

unintentional: negligence

Respondeat Superior

"Let the master answer" an employer is vicariously liable for the behavior of an employee working within his or her scope of employment

Res Ispa Loquitur "the thing speaks for itself"

situation in which a particular injury could not have occurred in the absence of negligence, patient is not at fault

Tort Law Doctrine

allowing the plaintiffs to infer a defendant's negligence through evidence

Image requisition requirements

- identification

- allergies

-specific exam

-clinical history (indications/ symptoms)

-diagnosis

-referring provider name

ARRT standards of ethics (3 parts)

Code of ethics- guide

Rules of ethics- mandatory

Ethics review process- investigates and handles violations

* know specifics of each

standard precautions

A strict form of infection control that is based on the assumption that all blood and other body fluids are infectious.

chain of infection

Infectious agent, reservoir, portal of exit, means of transmission, portal of entry and susceptible host

contact precautions

gloves and gowns

Droplet precautions

surgical mask

Airborne precautions

N95 mask, negative pressure room

Neutropenic precautions

immunocompromised, strict hand washing, private room, no raw veggies/fruits, daily baths, visitors are restricted

BUN

blood urea nitrogen

Normal: 7-21 mg/dl

Creatine

0.6-1.2 normal range

waste product (do not want it high)

GFR (glomerular filtration rate)

90-120 mL/min

Renal function

filtration (want this number high)

*tested before given contrast to check kidney function

Inverse relationship between Creatine and BUN to GFR

^ BUN or creatine = Decreased GFR

photoelectric effect

Photon completely absorbed and inner shell electron injected

-Increases PT dose

Compton effect (scatter)

* Contributes most to occupational dose

increased kvp does what to attenuation

decreases it

exposure

number of ionizations produced in air

unit: coulumbs/Kilogram (c/Kg)

absorbed dose

the amount of energy absorbed per unit mass

- cause for biological damage

-measured in Gray

Equivalent Dose (EqD)

used absorbed dose adjusted for type of radiation used

absorbed dose x radiation weighing factor

Effective dose (EfD)

*Best overall risk dose

- adjusted for tissue type

absorbed dose x weight factor x tissue factor

x-ray has weighing factor of 1

Linear Energy transfer

LET=total energy deposited/ track traveled

Relative Biological Effectiveness (RBE)

measurement unit used to compare the biological effects of different tissues irradiated by different forms of radiation

*different radiation = different damage

^LET=^RBE

LD 50/30

lethal dose for 50% or irradiated population to cause death in 30 days

*3-4 Gy without medical support

Radiolysis

The disassociation of water molecules following irradiation

-creates free radicals and toxic substances (hydrogen peroxide)

- indirect damage to DNA and cell functions

protraction

dose delivered continuosly over a long period of time

- gives healthy cells less time to recover

fractionation

dose is divided into multiple exposure times

-gives tissue a

Mitosis

prophase: chromosomes begin to become visible

M- Metaphase: chromosomes fully exposed; meet in the middle

*most radiosensitive phase

tele

interphase (apoptosis)

controlled self destruction of cell to prevent further damage before division

mitotic death

"genetic death" occurs when a cell dies after one or more divisions

Mitotic delay

Exposing a cell to as little as 0.01 Gy (1 rad) of ionizing radiation just before it begins dividing can result in failure of the cell to start dividing on time

Dose response relationships

nonlinear, nonthreshold: any dose can be harmful; harm increases nonlinearly with dose

Linear, nonthreshold: risk is proportional to dose, no safe level

linear, threshold: risk proportional to dose, with safe level

nonlinear, threshold: below this threshold there is no effect

non-stochastic effects

- determined threshold has to be met

- early or late effects ( ex: burns (early), cataracts (late)

Nonlinear: ^ dose = ^ severity and probability

*think about a sunburn: the longer you are in the sun the more chance yu have of sunburn

stochastic effects ( probabilistic or non-threshold)

- cancer or genetic mutations

Linear: ^dose = ^ probability but NOT severity

*think about playing the lottery: the more you play the more chances you have of winning, but the prize is the same

Early non-stochastic effects

fetal stages

Preimplantation 1st week (when egg is implanted, all or nothing)

Organogenesis: 10 days-6 weeks (most radiosensitive)

fetal stage: 6 weeks - term: exposure can cause cancer/functional disorders

Acute radiation syndrome

Hematopoietic: affects bone marrow causing infection and hemorrhage (1-10 Gy_

Gastrointestinal (GI): destroys lining, causing nausea, vomiting dehydration (> 10 Gy)

Central Nervous system syndrome: Neurological failure (>50 Gy)

stages of acute radiation syndrome

1. prodromal (right after dose is received (nausea, vomiting, skin reddening)

2. Latent: symptoms temporarily disappear (length of period dependent on dose)

3. Manifest Illness: full effects in place (ex: neurological damage-> seizures)

4. recovery or death

who should you last choose to radiate/hold

1. a technologist since they are around radiation most

2. woman of childbearing age (cannot reproduce reproductive cells)

3. Male (can reproduce sperm)

beam restriction requirement

must be accurate within 2% of SID

Fi

removes low energy photons, reducing skin and organ dose to PT

NCRP #102

2.5 mm lead requirement for filtration

Increased grid ration dose what to patient dose

increased due to need for use of higher exposure factors

minimum source to skin dose for fluoro (21 CFR)

fixed = 15"

Mobile (c-arm)= 12"

where should the image intensifier always be placed

above patient

secondary radiation consists of

leakage and scatter radiation

Primary barrier

blocks direct radiation

1/16 pb eq

secondary barrier

walls

1/32 pb ed

note: must be 1/2 inch overlap of barriers

protective tube housing

limit radiation leakage from tube to less than 0.88 mGy/hr at 1 meter (even at tubes maximum capacity)

minimum lead equivalents for protective wear

aprons- .50 mm

thyroid shield- .50

glasses- .35mm

gloves- .25 mm

curtain- .25 mm

bucky slot cover- .25 mm

NCR #102 and CFR fluoro requirement

cumulative timer: required to track exposure

exposure rates: normal mode < 10 R/min

dosimeter requirement

anyone receiving >10 mGy

Dosimeters

TLD: extremity detector

Pocket: uses gas as sensing material and gives immediate dose reading

OSL: uses aluminum oxide w/ copper, tin, and aluminum filters

NCRP #116 dose limit

Annual: 50 mSv

cumulative :10 mSv X age

Public: 15 mSv to eye and 50 mSv for skin, hands, and feet

eye: 150 mSv