Exam 1 (Radiation & Laser) Flashcards
1
Q
- What is mechanical radiation?
A
Only travels thru substances
2
Q
- What is nuclear radiation?
A
Unstable atom nuclei
3
Q
- What is cosmic radiation?
A
- Electrons only.
- Sun rays.
- Almost speed of light.
4
Q
- What is ionizing radiation?
A
Electrons knocked off atoms create ions
5
Q
- What is more harmful, non-ionizing or ionizing radiation?
A
Ionizing, d/t electrical charges causing chemical reactions
6
Q
- What are x-rays carried by?
A
By photons
7
Q
- A shorter wavelength means _____ energy?
A
Higher
8
Q
- What must happen for an electron to move back into its original orbit?
A
The orbit must release a photon
9
Q
- Which atom size is more likely to absorb photons?
A
Larger atoms (bones)
10
Q
- What is an example of small atoms & large atoms in the human body?
A
- Small= soft tissue.
- Large= bones
11
Q
- Explain the Anode in an x-ray machine?
A
- Positive charge.
- Made of tungsten
- Attaches electrons across the tube
12
Q
- Explain the Cathode in an x-ray machine?
A
- Filament in the center.
- Current heats filament.
- Heat causes electrons to fly off filament
13
Q
- What are the most common side effects of radiation therapy?
A
- N/V: (brain, pelvis, abdomen)
- Hair loss: (brain, breast, chest).
- Diarrhea: (pelvis, rectum, abdomen)
14
Q
- What are radiation doses measured in?
A
millirem (mrem) or rads
15
Q
- What are the annual allowable doses for radiation?
A
- Whole body: 5,000 mrem
- Extremities: 50,000 mrem
- Eye: 15,000 mrem
- Pregnancy: 500 mrem
16
Q
- An angioplasty exposes one to how many mrem?
A
5,700 mrem
16
Q
- A CXR exposes one to how many mrem?
A
5-10 mrem
16
Q
- An angiogram exposes one to how many mrem?
A
1,500 mrem
17
Q
- A CT exposes one to how many mrem?
A
5,000 mrem
18
Q
- A narrow collimation leads to _____ scatter?
A
Decreased
19
Q
- Moving from 2 feet to 4 ft from radiation source affects your exposure by what?
A
Only exposed to ¼ of mrem (20 mrem to 5 mrem)
20
Q
- MRI principles are based of?
A
- Static magnetic field &
- individual atom nuclei
21
Q
- What does an MRI use the magnetic field for?
A
To orient nuclei of Hydrogen molecules to north-south poles
22
Q
- How does fat & water appear using T1 MRI view/technique & what is a T1 used for?
A
- Fat= bright. Water= dark.
- T1 used for anatomy
23
Q
- What is a T2 MRI view used for?
A
- Pathology &
- identifies edema easily
24
Q
- What is the MRI contrast material made of & what are the side effects?
A
- Gadolinium.
- Side effects: itching, rash, abnormal skin sensation
25
Q
- How long does it take for Gadolinium to clear the system?
A
24hrs with normal GFR
26
Q
- Which vaporizer is MRI safe?
A
Sevoflurane
27
Q
- What body part is at risk for injury during MRI abdominal scans?
A
Brachial plexus d/t arms being over the head
28
Q
- How long does one have to wait to be MRI safe after endovascular or biliary stents, what about coronary stents?
A
- 8 weeks.
- Coronary stents are safe immediately
29
Q
- What happens to the electrons when the laser is in use?
A
Electrons become excited & move to higher orbit
30
Q
- What are the properties of lasers?
A
- Monochromatic: same wavelength.
- Coherence: photons travel synchronized in time & space.
- Collimation: beam photons are nearly parallel
31
Q
What are the mediums used in lasers?
A
- Argon
- CO2
- Nd YAG (neodymium-doped yttrium aluminum garnet)
32
Q
- What is the advantage of a CO2 laser & what locations are they great for?
A
- Minimal scatter.
- Great for vocal cord, oropharynx
33
Q
- What is the advantage of an Argon laser & what is it used for?
A
- Modest tissue penetration.
- Used in dermatology
34
Q
- What is a Nd YAG laser used for?
A
Tumor debulking (oncology)
35
Q
- What are the hazards of lasers?
A
- Atmospheric contamination
- Perforation of vessel or structure
- Embolism
- Inappropriate energy transfer
- Airway fire
36
Q
- Atmospheric contamination can lead to what & what are the S/S?
A
- Lead to interstitial PNE, bronchiolitis, emphysema, carciogenic.
- S/S: HA, nausea after inhalation
37
Q
- What is needed for the fire triad?
A
- Ignition source
- Fuel
- Oxidizer
38
Q
- What are the two major sources for OR fires?
A
- ESU (Electrosurgical units) (Cautery, etc)
- Laser
39
Q
- What are pledgets?
A
Soaked cotton like device placed around ETT
40
Q
- What should be avoided in laser procedures?
A
- Nitrous
- Keep O2 < 30%