practical Flashcards
1
Q
e-stim indications (5)
A
- pain
- muscle weakness
- edema
- wound healing
- diagnostic purposes
2
Q
transcutaneous e-stim works by triggering action potential. to do this we need: (3)
A
- sufficient intensity (amplitude)
- duration (width of pulse)
- speed of rise
3
Q
order of fibers e-stim works on and why (3)
A
- sensory (first tingle) -these have the widest diameter and most mylenated so they are excited quickest
- motor - this is what you see when u see affected when u see contractions; not actual muscle contractions
skip over if you put on bony prominence - pain (recruited painful nerve fibers)
4
Q
pulse intensity duration curve (2)
A
- PW vs. PI
2. shows better discrimination the narrower the pulse width (makes it easer to just trigger sensory)
5
Q
electricity definition
A
- electricity is flow of e-
6
Q
amplitude basics (4)
A
- amplitude is the # of e-
- height of pulse
factors that affect amplitude: - voltage - increase in voltage increases potential difference btwn point A & B => driving force for current 4. proportional relationship
- resistance (ohms)- how well a particular environment conducts the flow (healthy tissue has less resistance than necrotic tissue) 6. inverse relationship
7
Q
3 types of electrical current
A
- direct
- alternating
- pulsified
8
Q
direct current (2)
A
- flows in long pulse (1s or greater) in 1 direction
2. can be very irritating be careful
9
Q
alternating current (3)
A
- continous flow in 2 directions (switches polarities)
- short pulse width (ms)
- less irritating
10
Q
pulsatile current (3)
A
- most common
- 1 or 2 directions, but not continous monophasic or biphasic (symmetrical or a-symmetrical)
- narrowest pulse width (microseconds)
11
Q
4 setting on e-stim machine
A
- intensity
- frequency
- duration
- modulation
12
Q
pulse intensity
A
- height of pulse = amplitude (can change from subsensory -> sensory -> motor)
13
Q
pulse frequency (4- 1= low vs. high frequency)
A
- # pulses/ second
- increase frequency = decrease interpulse interval
- low frequency = twitching muscle vs. 50pps = tetanic contracion
- high for wound healing and electro-osmosis because you need polarity*
14
Q
pulse duration (3)
A
- pulse width
- to keep at sensory want low pulse width/ duration
- for muscles higher b/c want to have as much intensity as possible
15
Q
modulation
A
- continuous vs ramp