Principles Of Electrotherapy Flashcards
When does the flow of charged particles occur
When there is an Imbalance in the number of electrons located at two different points
What path does electricity take
Least resistance
flows from an area of higher electron concentration to an area of low electron concentration
What is a cathode
An area of high electron concentration
negative charged pole
What is an anode
An area of low electron concentration
positively charged pole
Which way does a direct current flow
One way
Which way does an alternating current flow
Back-and-forth
What is a direct current
Unidirectional flow of electrons that can be either positively or negatively charged
What is a direct current also known as
Galvanic current
Characteristics of direct current
Uninterrupted or constant
the flow of the current can be selected on the electrical stimulation unit from:positive to negative from negative to positive
What can a direct current create
Galvanic rash
What does direct-current have the potential to cause
Chemical reactions in the body tissues
What can occur at the anode
Acidic reaction
What can occur at the cathode
Alkaline reaction
What layers do chemical reactions happen in
Dermal
What do you use direct-current for
To stimulate the innervated muscle to prevent or reduce muscle fiber atrophy
iontophoresis
monophasic
What is an alternating current
Continuous change in direction of electron flow
flow is bidirectional
Equal balance bt two poles (neutralizes)
Why is there an equal balance between the two poles in alternating current
secondary to a constant change of directions of the charge particles
Characteristics of alternating current
Biphasic waveform
bidirectional current
maybe symmetrical or asymmetrical
maybe balanced or unbalanced
What is typically the most comfortable
Alternating currents
Pulsatile current or pulsed current characteristics
Electron flow is periodically interrupted
can be unidirectional
can be bidirectional
the flow of electrons is turned on and off in a rapid fashion
like a strobe light
What are the three pulsatile waveforms
Monophasic-One Direction
biphasic- back-and-forth
polyphasic-lots of starts and stops
What is a monophasic waveform
One phase to a single pulse
What is the flow of electrons in a monophasic waveforms
Unidirectional
What is the current flow in monophasic waveform
One Direction
Polarity of the monophasic wave form
Either negative or positive depending on the setting the therapist uses
What is a monophasic waveform used for
Direct stimulation of the innervated muscle
iontophoresis
What is a biphasic waveform
Two opposing electrical phases (positive negative)
What is the pulse in biphasic waveform
Bidirectional
Where is the lead phase in biphasic waveform
Above the baseline
Where Is the second phase in biphasic waveform
Below the baseline
When does a symmetrical biphasic pulse occur
When the two phases deviate from the baseline in an identical and equal amount
In what direction are the phases in symmetrical biphasic pulse
One phase in a positive direction
one phase in a negative direction
What to use symmetrical biphasic pulse for
Multiple motor points
large muscle contraction
more comfortable to patient than asymmetrical biphasic way forms
What is zero net charge
Two phases are equal in magnitude an duration
What are positive and negative phases like an asymmetrical biphasic waveform
Not identical
What is created in asymmetrical biphasic waveform
Net electrical charge
What is asymmetrical biphasic wave used for
Stimulation of the small for muscles
negative electrode over the motor nerve
What is Possible in asymmetrical biphasic wave
Physiological effects on tissue (Rash)
Where do you put the electrode for small intrinsic muscles
On top of the muscle belly
What is polyphasic waveform
Hey burst of three or more electrical phases
series of pulses delivered as a single charge
What is a polyphasic waveform perceived as by humans
Single pulse
What is burst frequency
A trade of pulses separated by an interpulse interval
What is medium frequency current inferential
Alternating low-frequency current that has been modified
What Does a medium frequency current inferential consist of
Two medium frequency currents (one said by machine the other by the therapist)
What do the two medium frequency currents do in medium frequency current inferential
They’re transmitted almost simultaneously
electrical current paths cross and interfere
What is a medium frequency current inferential used for
Pain
What are the clinical purposes of interferential
Pain management
decrease edema
increased blood flow
muscle stimulation
How to use interferential
For electrodes in a quadripolar configuration
What is Russian stimulation
A medium frequency current
Polyphasic alternating current waveform
What is Russian simulation used for
Improving athletic performance muscle mass and Force
severe weakness or atrophy
Poor endurance
What are the electrical parameters
Amplitude
duration
rate
What Is amplitude
The maximum amount of current or voltage delivered during a single phase of a pulse
What is pulse duration
Length of time between the beginning and the end of all phases in a single pulse
What is rate
The number of pulse cycles being delivered to body tissues
What is a sensory response
They tell you they feel it (20-150)
What is a motor response
Muscle moving(200-300)
What is a noxious response
Pain (600)
What happens as the phase duration increases
The depth of current will increase
The degree of chemical changes on the body tissues increase
What is a shorter pulse and shorter phase duration cause
Better conductivity of the current into the tissue with less impedance
What Determines the type of muscle contraction
Rate/frequency
What is the rate for twitch
1-20 pps
What is the Rate for mm contraction
25-50
What is the rate to fatigue (tetany)
50-80
Frequency of tens to use in acute pain
Higher
Frequency of tens to use in chronic pain
Lower
What is internists also called
Amplitude
Does intensity vary upon
Person and desired effect
pain
level of contraction
adipose versus muscle ratio
What is ramp
Descriptor of the rise and fall of the intensity to desired level typically 2 to 5 seconds
What is synchronous
All electrodes will go off at the same time
What Is reciprocal
Electrodes alternate on and off
What is duty cycle
Ratio of on off times
What will a duty cycle of 1:1 do
1:4
Rapid fatigue
Reduce fatigue
Monopolar active electrodes placed (ionto)
Inactive electrodes placed
At target site
distance from the first
Where are bipolar electrodes placed (tens NMES)
At area to be treated or along muscle belly
Electrodes placed for superficial structures
deeper structures
Closer together
further apart
PreCautions for electrotherapy
Decreased sensation unhealed incisions bony prominences pain burning sensation over growth plates skin irritations to electricity of Gels demand pacemakers heart disease carotid artery Eyes unstable fracture's history of seizures pregnancy Peripheral nerve disorder rapid fatigue syndrome's infections active cancer DVT
Clinical uses of symmetrical biphasic waveform
Quadriceps
hamstrings
muscles of the back
when combined muscle functions required
What is electricity
A type of energy that is capable of producing magnetic chemical mechanical and thermal effects
