Exam 2 Flashcards
___ involves the reproduction of microorganisms in the human body
Infection
___ is the collective term used to describe related clinical signs & symptoms associated with an infectious agent
Disease
___ is a person with an infection but no observable symptoms
Subclinical infection
___ is the reproduction of an infectious microorganism
Colonization
___ is a person who has an infection that has colonized but not ill
Carrier
___ is the presence of microorganisms on the body of an inanimate object
Contamination
___ is an infection that is acquired in the hospital setting
Nosocomial infection
Healthcare associated infections (HAI’s) include (9)
-pneumonia/surgical site infection
-gi infection
-UTI
-primary bloodstream infections
-eye, ear, nose, throat, mouth infection
-lower respiratory tract infection
-skin & soft tissue infection
-cardiovascular system infection
-bone & joint infection
Major cause of mortality amongst cancer patients is ___
infections
-caused by immunosuppression caused by treatments & frequent contact with HCW’s & settings
Disinfection examples include (4 items)
alcohol,
chlorine,
hp,
formaldehyde
Disinfection facts (3)
-does NOT eliminate bacteria spores
-kills all microorganisms
-used for non-critical items
Sterilization facts (4)
-destroys ALL organisms & spores
-ensures equipment & area are free of mo’s
-used for critical items (items inserted or contact w/ blood)
-used in surgery (sterile)
Direct transmission route:
contact>person to person spread
Indirect transmission route:
object that is contaminated is touched by an individual who becomes infected
Droplet is tranfered by (3)
coughing, talking, sneezing (w/in 3 ft)
Where do Droplets must be deposited for infection to spread (3)
nasal
Oral mucosa
eye
Common vehicle utilizes ___ to transmit ___
Fomite
Infection
Vector is a
live carrier of infection (ex: mosquito)
Airborne infection characteristics (2)
Smaller than droplet particles
Can travel & stay in the air 6 ft or greater
Non-specific defense mechanisms include (4)
-skin
-cilia
-secretions (like mucus)
-wbcs
Natural immunity devolps in result of
Having the specific disease
Artificial immunity is aquired by
vaccination triggering antibodies
Passive immunity is the
transfer of protective antibodies from one host to possible secondary host
-ex: maternal immunity to fetus through the placenta
Acme is the ___ of ___. Between ___ and ___ phases.
peak of disease
-between invasive & decline phases
Incubational period is the period of
no symptoms
Prodromal period def:
beginning feelings of feeling unwell
Invasive phase:
full blown symptoms
Decline phase:
symptoms brought under control
Convalescent period:
body is healing
Sequalae:
remaining symptoms the body cannot repair
Hepatitis B virus can live on surfaces for ___ days @ ___ temp
7
Room
Hepatitis B virus trasnmits through
Contact with infected blood and body fluids through skin breaks or mucous membrance contact
Hepatitis C virus transmits through (3)
- needle use (most common)
- infected blood
- skin breaks
Most common bloodborne infection in the U.S. is
Hepatitis C virus
Which virus has no vaccine
Hepatitis C virus
Influenza transmits through/by
Through large droplets (airborne)
Influenza self innoculation after
contact with contaminated material
Varicella-zoster virus:
- Cause
- Threatning to ___
- Transmission through
-caused by chickenpox & shingles
-life-threatening to immunocompromised pts
-transmission through droplets
Pertussis aka:
whooping cough
tetanus aka:
lockjaw
(caused by bacteria found in soil)
diptheria bacteria aka:
diptheria:
(spread through respiratory droplets)
Tuberculosis transmission:
airborne droplets from infected person sneezes, coughs, or talks
When in presence of a Tuberculosis patient (2)
-negative air flow room must be used
-must use n95 mask
HIV/AIDS started in (year)
1983
HIV/AIDS needlesticks account for ___% of job-related acquired HIV
84%
HIV/AIDS transmission between ___ & ___ is rare
Healthcare worker and patient
Universal precautions (3)
-apply to blood, body fluid, secretions, excretions, nonintact skin, mucus
-wear gloves if touching pts anywhere near an open wound or cleaning up body fluid
-never recap a needle
Healthcare workers should wash their hands when (4)
-before touching a pt
-after touching a pt or removing gloves
-when hands are moving from a contaminated site to a clean site
-after touching inanimate objects in the vicinity of a contaminated patient
Hand hygiene:
wash hands w soap __-__ seconds if hands are visibly soiled & after caring for someone w known or suspected ___
- 40-60 seconds
- diarrhea
Alcohol based hand rub should be rubbed in (time)
20-30 seconds
Alcohol based hand rub should be used unless hands are ___
Visible soiled
When to wash hands (5)
-visibly dirty or contaminated
-before eating
-after using restroom
-after caring for a pt known to have c diff or diarrhea
-after 10-15 alcohol rub applications
When to use alcohol rub: (6)
-hands not visibly soiled
-before & after touching a pt
-before inserting a catheter (or anything) into pt
-when moving from a contaminated body site to a clean one
-after touching an inanimate object within reach of a pt
-after removing gloves
Donning ppe: (4 in order)
-first gown
-mask
-goggles
-gloves
Removing ppe: (4 inorder)
-gloves
-goggles
-gown
-mask
PPE Precaution for contact transmission (2)
- Gown
- Glove
PPE Precaution for droplet transmission
Mask
PPE Precaution for airborne transmission:
n95 mask & respirator
PPE Reverse precautions: (3)
Used to protect immuinocompromised patients
- Mask
- Gown
- Gloves
Routine cleaning of a room: (4)
-equipment & room should be cleaned between each pt
-new pillowcases, sheets, table paper for each pt
-anything pt touches must be cleaned after each use
-blood or body fluids should be cleaned up immediately
Assessment is
a clinical plan that identifies the unique needs of the patient & how those needs will be addressed
Patient navigators provide assistance to pts as they move through: (3)
healthcare system
-medical
-social
-financial services
2 contents of verbal communication:
-cognitive: composed of the words & facts you say
-affective: feelings & emotions expressed
Protein-calorie malnutrition: often caused by change in _____. Patient has insufficient _______ intake, overall deficiency
- Taste
- Protein
2 types of malnutrition
-Marasmus (severe undernutrition)
-Kwashiorkor (lack of protein)
Marasmus develops from an extreme _______ deficiency
Calorie
Kwashiorkor consists of diet mainly of _____ & not enough _______
-carbs
-protein
Kwashiorkor leads to ____ loss, stunted ______, swollen _______, ______ wasting, behavioral & ______ changes
-Hair
-Growth
-Abdomen
-Muscle
-Mental
Oncology patients should have their weight checked _______
Weekly
2 types of pain:
-Acute (new/transient)
-Chronic (persistent > 3 months)
Examples of acute pain:
-back pain
-bowel obstruction
Examples of chronic pain:
-tumor invasion
-treatment side effects
T or F: Age, gender, race, & culture may affect a persons experience w/ pain
True
What causes erythema?
inflammation
Erythema radiation dosage
3000-4000 cGy
Dry desquamation radiation dosage
4000-6000 cGy
Alopecia radiation dosage
2000 cGy
Mouth changes (stomatitis, xerostomia, mucositis, taste changes, esophagitis) radiation dosage
2000-3000 cGy
Nausea/vomiting radiation dosage
1000-2000 cGy
Cancer patients are at an increased risk of ________________
myelosuppression
Myelosuppression is
Reduced bone marrow activity leading to less blood cells
Anemia
low rbc count
Leukopenia
low wbc count
Thrombocytopenia:
low platelet count
Air is a ________ contrast agent and appears _____
-Negative
-Black (radiolucent)
Barium & Iodine are ________ contrast agent and appears _____
-Positive
-White (radiopaque)
Osmolality: measure of how much one substance has _________ into another substance. The ________ the concentration, the higher the osmolality
-Dissolved
-Greater
T or F: If a patient experiences a reaction to contrast, check BUN & creatinine blood levels
True
BUN stands for ___ ___ ___ and evaluates ___ function
-Blood urea nitrogen
-Evaluates kidney function
Creatinine evaluates ___ function and ___ product levels
-Evaluates kidney function
-Evaluates waste product level (should be low)
Extravasation: ________ leaks out from IV & onto the skin
Contrast
Phlebitis:
inflammation of a vein
4 types of medications
-Antiemetic
-Analgesic
-Anti inflammatory
-Anti diarrheal
Antiemetic medications treat
-Treats nausea/vomiting
Which are antiemetic medications? (2)
-Compazine
-Norazine
has ZINE at end of name
Analgesia medications treat
pain
Which are analgesic medications? (2)
-Tylenol
-Percocet
Which are anti-inflammatory medications?
-Hydrocortisone
-Diprolene
Has “RO” in both names
Which are anti-diarrheal medications?
-Imodium
-Lomotil
Has “MO” is both names
Quality of life: A person’s __________ sense of well being derived from ________ experience of life as a whole
-Subjective
-Personal
What is the 2nd most common affective response in cancer patients?
depression
Cathode: (2)
charge and function
-negative side of the tube
-primary role is to produce electrons and focus them in the direction of the metal anode
Filament: function
coiled wire (tungsten) that passes electrons through wire heating them as they pass
Focusing cup: (2)
Charge and function
-negatively charged
-directs beam in a straight path
Anode:
Charge and function
-positive side of the x-ray tube
-receives electrons from the cathode, reduces the heat, & serves as a path for high voltage flow
Glass envelope: function
keeps air from colliding with electrons by creating a vacuum
Protective housing: function
controls unwanted leakage radiation
Quantity (mAs): is the # of
Photons
mAs & density are (relationship)
Directly proportional
Quality (kVp):
What is it
voltage that determines the kinetic energy of the electrons
kvp causes ___ & ___ in film
density & contrast
Density is on a image
:
degree of darkening on an image
-high density image is dark=low density is light
Distance is the
gap between the target and the recording medium
-inverse square law
Bremsstrahlung is made from
sudden deceleration of high speed electrons as they are deflected around the nucleus of the tungsten atom (75%-80%)
Characteristic radiation is created when
there’s a direct interaction of cathode electrons with the inner shell electrons of the target
Electrons that have sufficient energy to overcome the binding energy of the atom cause:
ionization
The line-focus principle: (3)
-allows a larger area of the target to be heated
-maintains a relatively smaller focal spot x-ray emission
-allows higher anode heating with small effective FS due to angling target
The heel effect: (2)
What is it
What causes it
-causes radiation intensity on the cathode side of x-ray tube to be higher than anode side
-caused by a differential in x-ray absorption by the target at different target thicknesses
The central ray/axis (2)
-imaginary line generated by the centermost x-ray in the useful beam
-intensity usually 100% at crosshai
To eliminate heel effect what is used (2)
Electrons
Photons
-scattering foil (electrons)
-flattening filter (photons)
2 types of units for superficial cancers and voltages:
-superficial (50-150 kV)
-orthovoltage (150-500kV)
Orthovoltage therapy unit: (4)
- Used with
- Depth limit
- Treatment locations (4)
- Cell types (2)
-used with cones or lead cutouts that lie directly on the patient
-depth limited to 2-3 cm
-treatment of skin, mouth, cervical lesions, keloids
-squamous cell & basal cell carcinomas
Cerrobend is made of: (4) ADD PERCENTAGE OF MATERIALS
Bismuth 50%
Lead 26.7%
Tin 13.3%
Cadmium 10%
(BLT with C)
Half value layer: (3)
- Def
- Dependant on what
- Why is it important
-thickness of any given material where 50% of the incident energy has been attenuated
-energy dependent
-important to determine how much shielding is needed
Linear accelerator:
charged particles travel in straight lines as they gain energy from an alternating electromagnetic field
Drive stand consists of: (4)
-klystron
-waveguide
-circulator
-cooling system
Kylstron: function
provides source of microwave power
Circulator:
- Function
- Prevents?
- directs radio-frequency energy into waveguide
- prevents backflow
Waveguide:
Function
channels microwaves into accelerator structure
Cooling system:
Function
controls temp of machine
Gantry consists of: (3)
-electron gun
-accelerator structure
-treatment head
Electron gun:
Function
produces & injects electrons into accelerator guide
Accelerator structure/guide:
synchronizes ___ with flow of ___
- microwaves
- electrons
Bending magnet:
bends the ___ through an ___ & onto the ___
- electrons
- angle
- x-ray target
Primary collimator:
shape the x-ray beam, set maximum field size
Beam-flattening filter:
distributes the x-ray beam across the field
Scattering foil:
distributes a pencil point beam of electrons evenly across the field
Ion chamber monitors: (3)
- symmetry across the field,
- dose rate,
- mu’s
Secondary collimators:
- defines the
treatment field size, (and the jaws)
Field light:
outlines the treatment radiation field
Portfilms:
verification films taken regularly to assure accuracy in treatment field placement
Divergence:
- is when photons move
- Contributes to
-straight but in different directions from focal spot
-magnification & distortion
Focal spot selection:
-electrons are emitted from a measurable area on the anode
-square or rectangle instead of a “true” spot or point source
Penumbra: (2)
- What is it
- Results from
-the area of unsharpness (fuzziness) at the edge of the beam
-results from photons intersecting the object at different angles
Large FS:
Means ___ ___
greater penumbra
Small FS:
- Means ___ ___
- Better ___
- less penumbra,
- better detail
Digitally recontructed radiograph (DRR):
- Reffer to
- Produced by
-refers to the sim film
-produced by CT slices pieced together or a “data set” acquistion that is compliled
Electronic portal imaging device (EPID):
-creates a
-provides a means
-creates a real-time image of treatment volume
-provides a means to improve daily treatment accuracy
SAD is always:
100 (isocenter)
SSD depends on: (2)
-location of tumor
-thickness of tissue
Is the SAD for an AP field the same for a PA or lateral field?
yes
Bolus does what: (4)
-increases skin dose
-decreases dmax
-eliminates “skin sparing effect”
-tissue equivalent material
Compensators may be: (3 items)
-bolus material
-pb filter
-wedge
Compensating filters function:
adjust the beam to deliver an even distribution of radiation across an irregular surface
Plain films serve what 2 major functions
-localization
-verification
Beam film:
utilizes the treatment beam to acquire a ‘time elapsed’ image of the treatment field & related anatomy
Verification for brachytherapy used to
verify position of implants (sources)
brachytherapy orthogonal films are at ___ and ___ degrees
0 and 90
Ways to keep dose to pt alara: (2)
-collimation
-improving technique to reduces # of repeat x-rays
Types of diagnostic imaging: (5)
- Xray
- CT
- MRI
- Nuclear scintigraphy
- Ultrasound
Nuclear imaging uses ___to image ___ ___ & ___ structures
- radioisotopes
- physiologic processes
- anatomic
Common body parts nuclear medicne scans: (3)
-bone
-liver
-lung
*bc of metastases
PET scans show (4)
-analysis of function
-blood flow
-extent of disease
-infarct extent
MRI/CT/Ultrasound:
-localization of ___
-difficult to differentiate ___ ___ from recurrence
-difficult ___ ___ assessment
-slow to assess ___ to therapy
-requires ___of contrast agents
Anatomic
-localization of mass
-difficult to differentiate scar tissue from recurrence
-difficult whole body assessment
-slow to assess response to therapy
-requires concentrations of contrast agents
PET:
-identification of change in cell ___
-straight forward ___ of disease from scar
-___ min whole ___ study
-fast ___ of therapy effectiveness
-trace quantities of ___ don’t change metabolism
Metabolic
-identification of change in cell biochem
-straight forward delineation of disease from scar
-30 min whole body study
-fast assessment of therapy effectiveness
-trace quantities of FDG don’t change metabolism
Image fusion:
output that results from 2 or more original studies which are combined
Benefits of image fusion: (2)
-give more info than any single imaging modality alone
-enhances both the diagnosis & treatment of cancer pts
Why PET in oncology?
-unique contribution to TNM staging
-facilitates more accurate & effective delivery while minimizing dose effects
What is FDG?
- What is it
- cancer shows up as
Fluoro-deoxy-glucose
-radioactive sugar given intravenously
-cancer shows up as hot spots on PET scan
Organs that normally uptake FDG (4)
-brain
-heart
-kidneys & bladder
Ultrasound in rad onc used in which treatments
-external beam: NOMOS BAT system
-brachytherapy: transrectal probe in combo w treatment planning system
BAT system: (2)
-facilitates daily localization of the prostate, bladder, & rectal wall
-allows for more accurate positioning of treatment fields
Ultrasound for prostate patients uses (4)
-facilitates volumetric measurement of prostate
-images directly transferred to treatment planning system
-allows for pre-implant planning of seed placement & dosimetry
-post-implant analysis
Fluoroscopy: (3)
-facilitated off-line setup & real time imaging & planning
-accuracy
-efficiency
Fluoroscopy uses: (5)
-field delineation
-organ localization
-PTV definition
-contrast administration
-implant verification
Why is CT the method of choice for RT planning? (4)
- Better diagnosis
-tumor & normal tissue localization
-density data for dose calcs
-treatment monitoring
Diagnostic CT charcteristics: (6)
-curved table top
-no lasers
-pt positioning not needed
-no immobilization
-small FOV
-organ fill ignored
Therapy CT characteristics: (6)
-flat table top
-required lasers
-pt positioning same as treatment
-immobilization
-external contour needed
-gas & urine affects size & position of organs
What things are the same for diagnostic & therapy CT? (2)
-contrast
-slice thickness
Advantages of CT sim: (5)
- Better ___
-ability to achieve ___ beam arrangements
-ability to ___ with tx planning computer
-visualization of ___organs
-ability to create ___ that previously couldn’t be produced
-accuracy
-ability to achieve various beam arrangements
-ability to interface with tx planning computer
-visualization of critical organs
-ability to create films that previously couldn’t be produced
Disadvantages of virtual simulation: (6)
-size of ___
-use of beam ___ ___ is limited
-___ limitations
-simples sims take ___ as long
-___movement
-DRR quality ___ than optimal
-size of aperature
-use of beam shaping devices limited
-mechanical limitations
-simples sims take twice as long
-organ movement
-DRR quality less than optimal
CT vs MRI:
-CT provides ___ axial images
-MRI can scan ___, ___, ___, or ___ planes
-MRI doesn’t use ___ radiation
-MRI has higher ___& better imaging of ___ ___
-CT provides transverse axial images
-MRI can scan axial, sagittal, coronal, or oblique planes
-MRI doesn’t use ionizing radiation
-MRI has higher contrast & better imaging of soft tissue
MRI:
-images based on ___ properties of ___ nuclei
-images indicate ___ activity in area scanned
-useful in ___ studies in ___ planning
-images based on magnetic properties of hydrogen nuclei
-images indicate cellular activity in area scanned
-useful in fusion studies in intricate planning
Computed Radiography (CR):
-concept of ___ environment
-generation of ___ images
-___& storage
-reduced/eliminated of ___ film
-reduction of ___ associated w ___ copy images
-concept of filmless environment
-generation of digital images
-archiving & storage
-reduced/eliminated of lost film
-reduction of cost associated w hard copy images
Quantity mAs is the number of
photons
Quantity kVp
is the voltage that determins the kinetic energy of electrons
The intensity of a radiation beam is
measured at 10.0 mR/hr at a distance of
10cm. What will the intensity of the beam
be at 20 cm?
2.5. slide #12 on powerpoint
Bremsstrahlung or Characteristic makes ionizating raditaion
Characteristic
___% of x-rays are turned into heat
99
The thickness of any given material where 50% of the
incident energy has been attenuated is know as the
HVL
Dmax
depth of maximum build up, in which 100% of the dose is deposited
Parallel Opposed Fields
opposite fields, defined
as fields with hinge angle of 180 degrees
Radical resection may be required to obtain
clean margin
Failure to obtain clean margins indicates
adjuvant radiotherapy
Ionizing Radiation in the form of
X-ray
Goal of rad therapy
deliver a sufficient dose of radiation
to sterilize tumor cells with minimal damage to
surrounding normal tissue
Amount of radiation used to treat tumors is limited by
tolerance of the surrounding normal tissue
The Ideal Situation
the tumor lies in an area
of tissue that is more radioresistant.
Living will aka
Advanced directive
Principal interaction in x-ray production is
a result of output form
bremsstrahlung radiation
Electrons that have sufficient energy to
overcome the binding energy of the atom
causing
ionization
Credited for discovery of x-rays is ___ in ___
William Conrad Roentgen
1895
Rapidly dividing cells are ___ susceptible to radiation damage
More
Rapidly dividing cells require ___ dose than slow dividing cells
Less
Intensity equation
I1/I2 = D2^2/D12^2
Types of non-ionizing radiation (2)
- MRI
- Ultrasound
