URR part one Flashcards
Standard precautions are an extension of ______
universal precautions
Universal precautions apply to direct contact with any ______, ______, and ______.
body fluids
airborne particles
skin wounds
Universal precautions apply to anything that has direct contact with an _____, _____, and _____.
body fluids
airborne particles
skin wounds
Universal precautions protect:
patient and caregiver
Universal precautions include:
good hygiene
handwashing
equipment cleaning
protective equipment
The CDC recommends the use of alcohol based hand rub when:
hands are not visibly soiled
Wash hands for ____
20+ seconds
Washing should be performed:
contamination
before putting on gloves and after gloves are removed
before and after assisting with any type of interventional procedures
between contact with patients
after changing exam table linens or paper
When putting on PPE, always put the _____ on first after washing your hands.
gown
All PPE should be removed prior to leaving the work area, except _______
respirators
Order for putting on PPE:
gown
mask
goggles
gloves
Order for taking off PPE:
gloves
goggles
gown
mask
Wear gloves when there is a potential contact with ____, _____, ______, _______ or _______
blood
body fluids
mucous membranes
nonintact skin
contaminated equipment
How to remove gloves properly
the first glove, pull the wrist section of the glove towards the fingers, turning the glove inside out as it is removed. Place the removed glove in the hand still wearing a glove. Pull the second glove off like the first and you should have both gloves inside out as it is removed
How to remove a gown properly
Remove your gloves, untie the strings, pull the gown forward from the shoulders using the neck strings, grab the inside shoulder seams, pull it off the arms and turn it inside out as it is removed
Wear a facemask to protect nose and mouth during times where contact with ______ and sprays of _____ or _____ is possible.
respiratory secretions
blood
body fluids
Wear eye protection during times where contact with ______ and sprays of _____ or ______ is possible
respiratory secretions
blood
body fluids
used to protect others from germs in patients that have stool incontinence, draining wounds and/or skin lesions that cannot be covered or uncontrolled secretions
contact precautions
enteric diseases
difficile, rotavirus, norovirus
wound and skin infections
MRSA, VRE, scabies, impetigo
used to protect others from germs in the patient’s nose, mouth, throat, and lungs
Droplet precautions
_____ precautions are used with patients suspected infection and that exhibit sneezing, coughing, or spitting
droplet
______ precautions are used for patients with pneumonia, influenza, adenovirus, mumps, rubella, meningitis, bordatella pertussis
Droplet precautions
Droplet precautions PPE
wear a facemask for close contact with the patient
wear gloves when touching the patient and items in the patient’s immediate environment
wear a gown or goggles if excessive spraying of respiratory fluids is anticipated
patient should wear a facemask when exiting the exam room
strict isolation, separation from others to prevent the spread by contact or airborne transmission of highly contagious diseases
airborne precautions
Infections associated with airborne precautions
tuberculosis, measles, chicken pox, shingles
Airborne precautions PPE
fitted N-95 mask or higher level disposable respirator when in the patient’s room
put respirator on before entering the room and after exiting the room
wear a gown and/or goggles if excessive spraying of respiratory fluids is anticipated
patient should wear a facemask when exiting the room
All items and personnel in a sterile field must be _____
sterile
When in doubt about sterility:
discard the potentially contaminated item and begin again
Sterile fields become ____ fields if left unmonitored
unsterile
Edges of sterile areas or fields, generally the outer ____ are not considered sterile.
inch
Sterile individuals must pass each other ______ when moving around the procedure room
back to back
_______ devices come in contact with intact skiin
non critical
______ devices come in contact with high risk patients, non-intact skin, or mucous membranes
semi critical
____ devices are used in a sterile field or within blood vessel
critical
___ or ______ disinfection performed for transducer used for standard examinations over intact skin
low
intermediate
____ disinfection refers to the use of a chemical solution on a transducer to release or eliminate all microorganisms, except bacterial spores
high
The type of high level disinfection used relates to differences in ___, _____, _______, ______, and ______
soak time
rinse time
temperature maintenance
required ventilation
duration of use of solution
Certain chemicals are unsafe to use on the transducer due to the potential for deterioration of the ______ and glues used to assemble the transducer
matching layer
Never immerse the _____ component of the transducer in the disinfectant
electrical
_____ and _____ are NOT acceptable for high level disinfectants
sprays
wipes
refers to the complete destruction of all living organisms on an object using exposure to heat, chemicals, or radiation
sterilization
Needle guides on transducers are ______ devices that require sterilization after each patient
critical
Transducers cannot be thermally sterilized because heating the PE element above the _____ can cause it to lose its piezoelectric properties/
Curie Point
PZT has a Cure Point of ______ degrees Celcius
300-400
Adult and child CPR __:__ compression to breath ratios single rescuer technique
30
2
Choking protocol standing
Heimlich Maneuver
Choking protocol unconsious
abdominal thrusts, open airway, 2 breaths
Syncope protocol
place patient on their back with legs elevated
created by congress to become apart of the Department of Labor; the purpose is to assure safe and healthful working conditions by setting and enforcing standards and by providing training, outreach, education, and assistance
Occupation Safety and Health Administration (OSHA)
_______ are the #1 risk for electrical shock to patient and technologist
cracks in housing
NPO status helps with:
reduction of bowel gas that could obscure adjacent structures
allows gallbladder to fill with bile for better visualization
decreases peristalsis in the GI to improve visualization of adjacent structures that could be obscured by part of the stomach or intestines
The Joint Commission recommends using __ identifiers for each patient
2
Acceptable identifiers
patient name
date of birth
medical record number
photo ID
professional negligence by a healthcare professional in which the patient received substandard care or treatment that caused harm, injury, or death to a patient
Medical malpractice
a legal doctrine that holds an employer legally responsible for the unlawful acts of an employee when they occur within the scope of their employment
respondeat superior
the principle that states that if an accident occurs, it implies negligence
res ipsa loquitur
defined as behavior that no careful, reasonable, or prudent person would commit
medical negiglence
______ is required for all invasive procedures
informed consent
mandates industry wide standards for health care information on electronic billing and other processes
HIPAA
individually identifiable health information
PHI
State and federal regulations prohibit the use of a patient’s ________ as an identifier on imaging exams
social security number
_____ frequency transducers are used for thinner patients and superficial structure
higher
small parts, extremity vascular, musculoskeletal exams should use the _______ transducer
linear array
abdominal, pelvic, OB should use the ______, ______, or ______ transducer
curved array
linear array
vector array
Cardiac exams should use the _____ or _____ transducer
sector array
vector array
Inappropriate presets can ____ the images and ______ exam time
degrade
extend
If the venous preset is selected for an arterial exam, _______ of the arterial signal is likely to occur
aliasing
Venous flow velocities are much ______ than arterial
lower
techniques used to prevent WRMSDs
ergonomics
Sonographers typically experience _____ and ____ issues
shoulder
neck
Arm abduction should be limited to a small angle and reach should be limited to __ cm or less to minimize potential injury
30
Sonographer that must stand should balance their weight on both feet to prevent ____ and ____ injuries
hip
back
Ultrasound system monitor should be adjusted to a position level with the sonographer’s line of sight that allows a _____ neck position
neutral
The wrist should be in a neutral position of flexed/extended at an angle less than ___ degrees
15
_____ function measures area of a circle
ellipse
most commonly used on OB biometry measurements
ellipse function
length x width
area
length x width x heightx 0.523
volume
commonly used to assess the bladder, ovaries, prostate, and cardiac chambers
volume
two factors that are related to each other and as one changes the other changes in the same way
directly proportional
If the Doppler shift increases, the calculated velocity _____
increases
If the power of the beam decreases, the intensity of the beam ______
decreases
two factors that are related to each other and as one changes the other changes in the opposite way
indirectly proportional
if the vessel diameter decreases, the velocity ______
increases
If the frequency of a sound wave decreases, the _____ wavelength of the beam ______
increases
100,000 cm is equal to ____
1 km
7 MHZ US probe uses ____ kHz or _____Hz
7000
7000000
5 mm is equal to __ meters
.005
65 cm is equal to ___ meters
0.65
4 MHz frequency increases by a factor of 4=
16 MHz
increase by a factor of means ______ by that number
multiply
Decrease by a factor of means _____ by that number
divide
4 MHz frequency decreases by a factor of 4 =
1 MHz
the inverse of a number
reciprocal
As the units get larger, the number gets ____
smaller
100mm =
10 cm
Distance units
mm
cm
volume units
cm cubed
area units
cm squared
mm squared
frequency units
Hz
wavelength units
mm
PRF units
kHz
PRP units
ms
intensity units
mw/cm squared
smallest unit of a digital memory
bit
bit is also known as
binary digit
a bit has a value of __ or __
0
1
a group of bits
binary numbers
system used by computers to process information
binary numbers
used to determine echo placement on our screens
binary numbers
binary number 0 =
position is off
binary number 1=
position is on
a term used to compare the relative powers, intensities, or amplitude of 2 sound energy levels
decibel system
changes in intensity are expressed in a logarithmic scale
decibel system
represent the ratio of 2 intensity levels
decibels
a +3 decibel increase will ____ the power or intensity
double
A -3 decibel decrease will ____ the power or intensity
half
used to describe numbers
logarithms
exponent to which the vase must be raised to produce that number
logarithm
categories of sound
infrasound
audible sound
ultrasound
diagnostic ultrasound
infrasound
<20 Hz
audible sound
20 H to 20 kHz
ultrasound
> 20 kHz
Diagnostic ultrasound
> 2MHz
______ and _____ properties of a material determine the speed of sound propagation in the material
stiffness
density
stiffness is also known as
bulk modulus
There is a significant increase in sound velocity with small _____ in stiffness of the material
increases
an increase in ____ results in a slight decrease in the sound velocity
density
the opposite of stiffness
compressability
Increasing compressability causes a decrease in ______
propagation speed
a ______ wave requires a medium to travel
mechanical
move through matter by causing molecules to vibrate successively along their path
sound waves
carry energy from one point to another; no matter or particles are carried along the waveform
sound waves
the conversion of electrical energy into mechanical energy- transmission of the sound beam
piezoelectric effect
the conversion of mechanical energy into electrical energy- receiving the reflected beam information
piezoelectric effect
_______ is applied to the piezoelectric material which vibrates (expands and contracts) to produce mechanical sound or pressure waves
electricity
_______ cause mechanical vibrations (acoustic pressure) of the piezoelectric material that are converted into the electrical signal for the display
returning sound waves
certain types of materials that produce a sound wave when pressure deforms them from voltage applied
piezoelectric materials
Average propagation speed in a PE element is _____
4-6 mm/ms
most common material used for transducer
lead zirconate titanate
ceramic materials used for transducer
lead zirconate titanate
barium titanate
lead metaniobate
lead titanate
Natural elements used for transducer
quartz
tourmaline
rochelle salt
natural element used in musculoskeletal and other high frequency superficial imaging probes
quartz
If a transducer is reheated above the Curie point, ______ may result and the element will lose the ability to produce sound waves
depolarization
________ production uses two piezoelectric elements, one to transmit and one to receive
continuous wave
_______ production uses one piezoelectric element and alternates using it to transmit and receive sound waves
pulsed wave
partical motion parallel to wave motion
longitudinal sound wave
requires a medium to travel
mechanical sound wave
positive amplitude of a wave, an area of high pressure and particle density on a pressure wave
compression
negative amplitude of a wave, an area of low pressure and particle density on a pressure wave
rarefaction
one compression and one rarefaction
cycle
four types of recordable changes occur with the mechanical interaction of the wave and the medium
pressure
temperature
density
particle motion
Changes in acoustic variables can lead to damage to the medium, called ______
bioeffects
particles move parallel to the direction of the wave movement
longitudinal
particles move perpendicular to the direction of the wave movement
transverse
difference between the average value and the maximum value of the wave intensity (compression)
amplitude
difference between the average value and the minimum value of the wave intensity (rarefaction)
amplitude
height of the compression or depth of the rarefaction
amplitude
indicates relative intensity or strength of the wave
amplitude
the difference between the minimum and maximum value of the sound wave intensity
peak to peak amplitude
amplitude _____ as it travels through tissue and attenuation occurs
decreases
amplitude is proportional to _____
power/voltage
Amplitude squared =
power
If the amplitude decrease by 1/2 of the original power, the power _____ by ___ of its original value
decreases
1/4
if the amplitude decreases to 1/3 of the original value, the power ____ to ___ of its original value
decreases
1/9
Amplitude is operator adjustable with _____
output power controls
rate energy transmitted into substance OR the rate at which work is performed
power
units of power
W or mW
units of amplitude
mm or cm
Power is operator adjustable with _____
output power controls
Higher power settings are related to an increased risk for the occurrence of ______
bioeffects
_____ diminishes as the wave travels through a medium
power
If power doubles, intensity _____
doubles
If power triples, intensity _____
triples
If amplitude doubles, power increases to ____ its original value
4x
If amplitude triples, power increases to ____ original value
9x
the rate energy travels through a substance
intensity
best indicator for the related risk of bioeffects
intensity
____ and ____ are inversely related in regards to intensity
power
area
Intensity = ____/_____
power
area
units of intensity
mW/cm squared
Intensity is operator adjustable with ______ and ______
output power
electronic focusing
As beam power increases, intensity _____
increases
The intensity at a more shallow focal zon will be _____ than the intensity at a deeper focal zone on the same US beam
highe
The wider the element, the greater the _____
beam area
The larger the area of the beam, the lover the ______ of the beam when power is constant
lower
If beam area doubles with no change in power, intensity is reduced to ____
50%
The smaller the area of the beam, the _____ the intensity of the beam when power is constant
higher
If the beam area is decreased by 50% with no change in power, intensity is _____
doubled
the depth at which the intensity of the beam is reduced to ____ the original intensity
1/2
______ reduces beam intensity as it travels through the tissue
attenuation
speed of the wave as it travels through a medium
propagation speed
Propagation speed is determined by:
the medium
Standard propagation speed in soft tissue
1540 m/s
Fastest to slowest propagation speeds
solids
liquids
gases
Range of propagation speed in the human body
500 m/s - 4000 m/s
Propagation speed only changes when:
the sound wave travels into a different media
_________ does not vary with frequency or wavelength of the sound waves
propagation speed
number of vibrations per second of an energy waveform
frequency
number of cycles per second in a sound wave
sound frequency
Each cycle consists of a ______ and a ______
compression
rarefaction
Frequency of sound is measured in ____
Hertz
one cycle per second =
1 Hert
1,000 cycles per second =
1 kiloHertz
1,000,000 cycles per second =
1 MHz
Pulsed US frequency varies with the _____ of the element and the _____ of sound in the element
thickness
speed
Continuous US frequency is determined by ______ applied to the element
electrical frequency
_______ remains constant at all depths as the sound wave travels through a medium
frequency
_______ does NOT change is you change from pulsed to continuous transmission
frequency
Diagnostic US = __-__ MHz
2-15
The choice of frequency for an exam is dependent on the ______ and _______ needed for an optimal exam.
penetration
resolution
the time it takes for one cycle to occur
period
_____ is the reciprocal of frequency
period
1/frequency=
period
an frequency increases, period _____
decreases
Units for period
sec, ms, us
Diagnostic ultrasound period
0.08-0.5 us
Lower frequency waves have _____ period and _____ wavelengths
lower
longer
____ remains constant when traveling through a medium
period
the distance traveled by one cycle
wavelength
wavelength is measured in ___
mm
Average wavelength of ultrasound in soft tissue
0.1 - 0.8 mm
______ is inversely related to frequency with sound propagation
wavelength
The higher the frequency, the _____ the wavelength
shorter
ONLY sound parameter determined by the US system/probe and medium
wavelength
The US system determines the ____ of the wave and the ______ varies with the medium in which the wave travels
frequency
propagation speed
Lower frequency waves have ____ period and _____ wavelengths
longer
longer
Sound waves with _____ wavelengths are preferred to produce the best 2D images
shorter
occurs when two waves with different frequencies are produced at the same time and combine to form a new wave
interference
original waves are waves that are out of phase; resultant amplitude is smaller than ONE of the individual waves
destructive interference
the individual waves become tangent to each other and have the same phase relationship; resultant amplitude is larger than BOTH of the individual waves
constructive interference
Interference is associated with ______ and +++++
acoustic speckle artifact
reduced signal to noise ratio
explains the hourglass shape of the beam
Huygen’s priniciple
sound waves produced by ultrasound transducers originate as numerous points on the surface of a piezoelectric element
Huygen’s principle
progressive decrease in beam intensity, power, and amplitude as it travels through the medium
attenuation
______ is described in negative decibels
attenuation
Attenuation occurs due to _____, _____, ______, and _____
reflection
refraction
absorption
scatter
______ is the predominant factor causing attenuation of the US beam
sound absorption
Attenuation is counteracted by ______ the TGC setting for the far field
increasing
________ is directly related to the distance the beam travels and transducer frequency
attenuation
Higher transducer frequencies exhibit faster attenuation rates in soft tissue =
less penetration
Longer travel distances ______ beam attenuation
increase
amount of attenuation of sound per cm
attenuation coefficient
unit for attenuation coefficient
dB/cm
used to describe attenuation in different tissue types
attenuation coefficient
Higher attenuation coefficients indicate ______ attenuation
increased
A way to describe attenuation with a specific distance of the sound traveled
attenuation coefficient
The farther the sound wave travels, the _____ the attenuation
greater
Attenuation coefficient is directly related to transducer ______
frequency
Attenuation coefficient value does not vary with ______
path length
Attenuation coefficient for soft tissue is equivalent to ____ the frequency
1/2
-dB = attenuation coefficient(dB/cm) x path length (mm)
total attenuation
tissue thickness that will decrease beam intensity by 50% or -3 dB
half value layer
also known as depth penetration, half boundary layer, penetration depth
half value layer
Half value layer typical range
0.25-1.0 cm
Half value layer is ________ to frequency
inversely proportional
ultrasound energy is converted into heat energy that is absorbed by the tissues through which it travels
absorption
______ has the greatest effect on US beam attenuation in soft tissue
absorption
Absorption ______ with transducer frequency and imaging depth
increases
Absorption is related to ______
thermal bioeffects
Average rate of attenuation/absorption in soft tissue
0.5 dB/cm/MHz
redirection of the sound beam back toward the transducer
reflection
requires perpendicular incidence along with a difference in acoustic impedance of two media along its path
reflection
The greater the difference in impedance between the two media, the greater the amount of ______
reflection
Not all reflections reach the transducer face due to ______
oblique angle of incidence
Usually less than __% of the incident US energy is reflected at a soft-tissue boundary between different media (muscle and blood)
1
___ of the sound beam is reflected at a tissue-bone interface
50
__% of the sound beam is reflected at a tissue-air interface
99
portion of the beam that exits the transducer and enters the body
incident beam
portion of the beam that is not reflected
transmitted beam
portion of the beam that is returned to the transducer due to reflection
reflected beam
the area where the transmitted and reflected pulses cross each other
zone of sensitivity
Perpendicular incidence is also known as ______ or ______
normal incidence
orthogonal incidence
beam strikes the boundary of two media at a 90 degree angle
perpendicular incidence
Perpendicular incidence is required for _____ and _____ of waves to the transducer
reflection
return
_______ is perpendicular in relation to the media boundaries
incident beam
Not all of the beam is reflected, the _______ continues on through the tissue
transmitted beam
Impedance of the media is directly related to the _______
amount of reflection that occurs
With 2D imaging, the ______ refers to a beam that is perpendicular to the media boundaries being evaluated to allow for total reflection
critical angle
___% reflection occurs when the beam strikes a smooth surface as the critical angle of insonation
100
occurs when the incident beam strikes the media boundaries at an angle other than 90 degrees
oblique incidence
acute angle
less than 90 degrees
obtuse angle
more than 90 degrees
incidence angle =
reflected angle
If the incident angle is 45 degrees, the angle of reflected waves is _____
45 degrees
leads to decreased structure visualization because less reflections go back to the probe
oblique incidence
Oblique incidence is related to ______ if wave crosses between two media with different propagation speeds
refraction
Reflection that only occurs when wave hits a large, smooth surface with perpendicular incidence
specular reflection
The amount of reflection _______ as the difference in acoustic impedance of the two medias increases
increases
The amplitude of the reflection will be _____ with perpendicular incidence
greatest
Not all specular reflections are returned to the transducer, those that strike the smooth surface at an _________ angle do not return to the transducer
oblique
waves are redirected but are somewhat organized
diffuse reflection
occurs with large, rough, or irregular tissue interface
diffuse reflection
surface irregularities are larger than the incident beam wavelength
diffuse reflection
specular reflection is also known as
backscatter
disorganized scatter
non-specular reflection is also known as
Rayleigh scatterer
occurs when a sound wave strikes a particle that is smaller in size than the incident beam wavelength
non specular reflection
A red blood cell is _______
non specular reflector
Sound is redirected in all directions from reflector
non specular reflector
