Interferential, Biphasic Pulsed Currents, And Microcurrents Flashcards
1
Q
Electrotherapy can help us with what things?
A
Pain modulation
Promoting tissue healing
Preventing/reducing edema
Increasing circulation
Muscle relaxation
2
Q
T/f: ES can be used to increase blood flow in superficial and deep tissues
A
True
3
Q
T/f: increased circulation can be accomplished using various different types of ES
A
True
4
Q
Local (superficial) increase in blood flow occurs with _____ frequency TENS at a _____ level by vasodilation of _____ vessels
A
Low, sensory, cutaneous
5
Q
Deeper arterial blood flow increases with _____ level stim, using rhythmic musc contractions
A
Motor
6
Q
Does deep blood flow increase with sensory level stim?
A
No
7
Q
Muscle contraction with ____ level creates a muscle pump for circulation
A
Motor
8
Q
When wanting to increase blood flow, where should we put the electrodes for best efficiency?
A
Over the ganglions
9
Q
When wanting to control pain, where should we put the electrode for best efficiency?
A
Over acupressure points
10
Q
When is NMES with what is even more beneficial for increasing microcirculation and decreasing edema?
A
When with muscle contractions
11
Q
T/f: a decrease in 6MWT time leads to an increase in function
A
True
12
Q
What type of stim promotes local (superficial) blood flow?
A
Sensory level stim
13
Q
What is the waveform used to promote superficial local blood flow?
A
Monophasic or biphasic pulsed
14
Q
What is the frequency for promoting superficial local blood flow?
A
4-100 pps (lower 4 shown to be more effective than 100)
15
Q
What is the pulse duration for promoting superficial local blood flow?
A
4-600 usec
16
Q
What is the amplitude for promoting superficial local blood flow?
A
mA to comfortable sensory level
17
Q
How long should we do ES to promote superficial local blood flow?
A
10-30min
18
Q
A
19
Q
What is the electrode placement to promote superficial local blood flow?
A
Over the tissue area where increased blood flow is desired, dermatomes, sympathetic ganglion
20
Q
What type of stim is used to promote deeper arterial/venous blood flow?
A
Motor level stim (NMES)
21
Q
What is the waveform used to promote deeper arterial/venous blood flow?
A
Biphasic pulsed current or burst modulation AC (Russian)
22
Q
What is the frequency used to promote deeper arterial/venous blood flow?
A
35-80 pps
23
Q
Why should we not use higher than 80 pps to promote deeper arterial/venous blood flow?
A
Bc it can create tetany and fatigue the muscle leading to no response
24
Q
What is the pulse duration used to promote deeper arterial/venous blood flow?
A
100-600 usec
25
What is the amplitude used to promote deeper arterial/venous blood flow?
mA to robust tetanic contraction
26
What is the duty cycle used to promote deeper arterial/venous blood flow?
1:1 on/off
27
How long should ES be left on to promote deeper arterial/venous blood flow?
10-15 min
28
What is the electrode placement to promote deeper arterial/venous blood flow?
Over the muscle of the area desired (find motor units for quicker contractions)
29
What is interferential current (IFC)?
Interference or superimposition of 2 symmetrical but asynchronous, kilohertz frequency (really high frequency), AC, resulting in a single treatment or interference current with properties uniquely different than the 2 og currents
30
What type of ES has two waveforms coming out at different frequencies?
IFC
31
T/f: IFC is more comfortable bc the carrier frequency is high and can go deep in tissues
True
32
What is constructive interference?
In IFC when the amplitudes of the 2 currents summed together
33
What is destructive interference?
Equally periodic, currents out of phase, and amplitudes that negate each other
34
Why is IFC referred to as amplitude modulated AC?
Bc of the modulation of amplitude that occurs with the intersection of the two currents
35
What is the beat frequency of IFC?
The currents are maximally in/out of phase at a rate equal to the difference bw the frequencies of the currents interfered
36
If the two currents in IFC have frequencies of 4000Hz and 4100Hz, what is the beat frequency?
100Hz
37
What is the typical range of beat frequency?
1-250 Hz
38
T/f: amplitude of IFC will peak and fall at a frequency equal to the beat frequency
True
39
What is the carrier frequency in IFC?
The frequency of the lesser of the 2 interfered currents, typically 1000-10,000Hz
40
____ carrier frequency is perceived as more uncomfortable
Lower
41
T/f: there is evidence that higher carrier frequency is better than lower carrier frequency in IFC
False, there is no evidence to support selection of one carrier frequency over another
42
Does the beat frequency or carrier frequency affect the tissues in IFC?
The beat frequency
43
The ______ _______ reflects the therapeutic frequency
Beat frequency
44
The ____ _____ elicits the therapeutic effect of physiologic effects on IFC
Beat frequency
45
T/f: The higher the carrier frequency the better the depth of penetration but shorter the phase duration
True
46
What are the suggested advantages of IFC?
Reduction in skin impedance with medium to high frequency currents
More current is concentrated in deeper tissues due to amplitude magnification at the intersection of 2 independent waveforms
Pain modulation
Greater comfort since less intensity is needed to drive the current through the skin
Increased arterial and microcirculatory blood flow
47
_____ and _____ frequency currents can reduce skin impedance in IFC
Medium, high
48
Why does medium and high frequency currents reduce skin impedance in IFC?
Likely due to the short pulse duration resulting in deeper penetration
49
Is there more or less discomfort with medium and high frequency IFC than with low frequency
Less
50
You need to increase the ____ for greater depth of penetration with low frequency stimulators
Voltage
51
Why is more current concentrated in deeper tissues due with IFC?
Bc of the amplitude magnification at the intersection of 2 independent waveforms
52
T/f: there is likely greater comfort with IFC due to the fact that less intensity is needed to drive the current through the skin
True
53
T/f: IFC can provide “nerve block” through Wedensky inhibition
True
54
55
What is Wedensky Inhibition in IFC?
When the nerve receives too much excitation and shuts down, creating a numbing effect
56
What are the proposed physiologic mechanisms for IFC?
Gate control theory (SC level interneurons)
Increased circulation
Descending pain modulation (increased intensity)
Nerve block pain modulation
Placebo
57
What is quadripolar IFC?
Using 4 electrodes positioned so that the 2 different frequency currents intersect each other perpendicularly within the tissue of the pt.
58
What is the point of intersection and site of new interference current in quadripolar IFC.
The assumed geometric center of the electrodes
59
T/f: the geometric center cannot be accurately determined bc of non-homogenous tissue resistances, so the current will take the path of least resistance, causing the path of one or both currents to be altered
True
60
Does placement of electrodes matter with IFC?
YES
61
What is the vector scan IFC modulation?
A modulation of the amplitude of one or both input currents offered in some units
62
63
What does the modification of amplitude of one or both input currents in some IFC units result in?
Rhythmic change in position of the interference pattern (feels like a little massage)
64
What is the vector scan thought to do in IFC?
Increase the effective treatment area
65
What is the sweep modulation of IFC?
Modulation of the beat frequency causing an automatic and rhythmic increase and decrease in the carrier current
66
67
What is the purpose of rhythmic mode (sweep modulation) on IFC?
To reduce accommodation
68
How long should treatment be with sweep modulated IFC?
10-30 minutes
69
Why should we not do more than 60 minutes of sweep modulated IFC?
Bc it is a lot of higher current going in and can pose a burns risk
70
IFC can modulate _____ or ______ to prevent accommodation
Beat frequency, amplitude
71
What is swing modulation on IFC?
Temporal characteristics of sweep pattern (changing the timing of the beats)
72
What is the benefit of swing modulation in IFC?
To avoid accommodation
73
What are the parameters for linear/continuous sweep modulation?
2-2 sweep 100-10Hz that will decrease continually over 2 sec then increase continuously over the next 2 seconds
74
What is peak to peak sweep modulation?
2f2 sweep 100-10Hz
Beat frequency will remain at 100Hz for 2 sec b4 switching to 10Hz for 2 sec
For analgesic tolerance
75
What is premodulated IFC?
Created by interference of 2 different medium frequency alternating current WITHIN THE STIMULATOR DEVICE with similar benefits to IFC
76
What is the benefit of using preamodulated IFC over a quadripolar IFC?
It is easier to set up and can be used for smaller areas
77
T/f: currents interfere within the tissues with premodulated IFC
False, they interfere within the device then come out as a single current
78
What kind of IFC is only a single current delivered using 2 electrodes, not quadripolar?
Premodulated IFC
79
What is a good option for IFC use on the elbow, wrist, or for CTS/radicular symptoms?
Premodulated IFC
80
What are the indications for IFC?
Pain modulation
Neuromuscular ES
Increase circulation
Reduce edema
81
Why is it significant that the use of IFC can reduce need for opioids?
Bc opioid use causes constipation, which poses a fall risk in geriatric patients, so if we can decrease their reliance on opioids, we can decrease their fall risk
82
T/f: we can use IFC for pain modulation in compression fractures in geriatric populations with osteoporosis
True
83
Does biphasic pulsed current use symmetrical or asymmetrical waveforms?
Either
84
Is asymmetrical or symmetrical biphasic pulsed current better?
There is no evidence that either one is better
85
What can biphasic pulsed current be used for?
Improved circulation, NMES, FES, and pain modulation
86
What do NMES and FES do?
Activate skeletal muscle
87
What is the pulse duration for biphasic pulsed current?
200-800usec
88
What is the frequency for biphasic pulsed current?
35-80Hz
89
What is the amplitude for biphasic pulsed current?
Strengthening to max contraction
FES to level needed for fxnal use
90
What is the duty cycle for biphasic pulsed current?
10s on/50s off
10 contractions
Adjust based on treatment goals and pt tolerance (typical starting EDC)
91
What is the ramp for biphasic pulsed current?
1-2s for NMES
92
To strengthen muscles you need a _____ MVIC
higher
93
What is FES?
using NMES to get the muscle contraction to do something functional
94
For FES, do you need a high MVIC?
No, just enough to reach the threshold for the contraction needed for the action
95
What are biphasic pulsed current and Russian stim used for?
Muscle strengthening
96
What is variable muscle stim (VMS)?
Symmetrical biphasic pulsed current with fixed interpulse interval to produce a greater phase charge than Russian
97
What ES can produce pain modulation?
Sensory, motor, brief intense, burst, modulated, or noxious TENS
98
What is microcurrent?
Low volt pulsed current
99
What is the waveform of microcurrent?
DC or monophasic pulsed current
100
If microcurrent is pulsed current, what is the pulse duration typically?
500msec
101
What is the frequency of microcurrent?
1-1000Hz
102
What is the treatment duration of microcurrent?
Minutes to hours
103
What is the intensity of microcurrent?
Less than 1mA
Current insufficient to excite sensory or motor nerves
104
What are the indications for microcurrent?
Inflammation
Post-op trauma
Soft tissue injury
Swelling
Fractures
Wound healing
Pain control (myofascial and neuropathic pain)
105
How does microcurrent promote wound healing?
By having biological effects on cells and substrates of healing
106
When would microcurrent be used for pain control?
When the pt is unable to tolerate sensory feeling of stim
107
What is the effect of microcurrent with currents from 50-1000uA?
Increased ATP levels
108
What is the effect of microcurrent with currents >1000uA?
ATP concentrations are leveled
109
What is the effect of microcurrent with currents >5000uA?
Decreased ATP concentrations
110
What is the effect of microcurrent with currents at 500uA?
Increased protein synthesis
111
What is the effect of microcurrent with currents >5000uA?
Suppressed protein synthesis
112
With frequency specific microcurrent, what is the treatment time?
A few minutes at each frequency until a feeling of the tissue going “smoosh”
113
T/f: FSM (frequency specific microcurrent) causes tissue softening and warming
True
114
What is the effect of FSM of 0.3Hz?
Healing
115
What is the effect of FSM of 3Hz?
Stimulating acupuncture points
116
What is the effect of FSM of 30Hz?
Controlling pain
117
What is the effect of FSM of 300Hz?
Reducing edema and stimulating lymphatic flow
118
What does the evidence say about microcurrent?
That is is good for wound healing
Limited evidence to support its use for treating MSK injuries
119
T/f: microcurrent ES can be applied to the skin to promote tissue healing
True
120
How does microcurrent promote tissue healing?
The ES produces a current in the tissues that mimics the natural skin battery and stimulates the body’s mitochondria to increase production of ATP
121
Studies support the use of LIDC (microcurrent) for what ulcers?
Venous ulcers
Ischemic ulcers
Non healing ulcer
122
Does the theoretical basis underlying the application of microcurrent involve nerve fiber depolarization?
Nope
123
T/f: microcurrent can be used to treat MSK injuries
False
