Passive Care- Exam 1- Electrical Stimulation Terminology

What are the physiologic effects of electrical stimulation?

Decrease pain

Decrease muscle spasm

Reduce edema

Stimulate exercise by muscle contraction

Stimulate healing

What does electrical stimulation stimulate exercise by muscle contraction?

Increase muscle fiber recruitment

Retard atrophy

What is the flow of electrons through a conductor?

Electricity

What is the number of electrons?

Current

What is the potential energy of electricity?

Voltage

What are some examples of resistance for electricity?

Length of conductor

Cross sectional area

Temperature

You have the lease amount of resistance when?

Short smooth large diameter wire

When you have too small of a wire, it increases resistance and with that it produces?

Heat

-why electrical fires can happen

What is the ability of a material to store a charge?

Capacitance

What is current flow in one direction/

Monophasic current

A monophasic current has both unique _________ and _____________

Positive and negative electrodes

What the name for monophasic current?

Direct current (DC)

-kind in the battery

What is the AKA for direct current (monophasic current)?

Galvanic

The net charge for monophasic current has both a ________ and _______ electrode with charge that builds up in the _______

Positive and negative electrode

Builds up in tissue

For monophasic current if it starts positive than? What about negative?

Starts positive, stays positive

Starts negative, stays negative

What is more dangerous, monophasic or biphasic current?

Biphasic current

What is biphasic current called?

Alternating current (AC)

What occurs with biphasic current (alternating current)

Flow of electrons changes direction regularly

What wave form is the same shape in both phases for alternating current?

Symmetrical

What wave form is different positive and negative for alternating current?

Asymmetrical

What net charge for alternating current is equal electrical charge in both phases?

Balance

What minimize or eliminate the polarity effect in the tissues during alternating current?

Balance net charge

What is an unequal charge for net charge of alternating current?

Unbalances

What are the different types of shape that biphasic (alternating current) can be?

Sinusoidal

Square

Rectangular

Triangular

Different ______ are used for different therapy's using biphasic current

Shapes

What is the phase duration?

Time it takes current to leave the isoelectric line to when it returns to this line

For biphasic phase duration, there are _____________ for each pulse

Two phase durations

For monophasic phase duration, the ________________

Phase duration and pulse duration are the SAME

Tissues response to _____________ NOT __________

Phase duration NOT pulse duration

A phase duration must be long enough to?

Overcome capacitance and cause an action potential

Large diameter nerves have a __________ capacitance and reach threshold ____________

Low

Quickly

What is the intensity or magnitude of the current?

Amplitude

What is the maximum amplitude of the current regardless of duration?

Peak current

What type of nerve fibers are close to the skin and have a lower threshold so will be stimulated first?

A-beta fibers

High peak current is associated with _____________

Greater depth of penetration

What is the amount of current supplied over a period of time/

Average current

Average current takes what into consideration?

Peak amplitude and the phase duration

What describes the relationship between amplitude (strength) of the electrical current and the duration (Phase duration)?

Strength duration curve

What will happen if the charge is sufficient to overcome the capacitance of a nerve?

It will depolarize

If the charge does not exceed the capacitance of a nerve fiber, what will happen?

No depolarization will occur

What was capacitance?

Ability of material to store charge

What fibers are targeted when the patient reports tingling but no muscle twitch?

Exceeded A-beta fibers but not A-alpha motor neurons

What fibers are activated when there is a muscle contraction?

A-alpha motor neurons have been exceeded

What fibers are activate when the patient reports burning, needling sensation?

Exceeded the A-delta fiber capacitance

What is the minimum amplitude needed to depolarize a nerve fiber when phase duration is infinite?

Rheobase

What will happen if peak amplitude fails to exceed rheobase?

Nerve will not depolarize regardless of phase duration

What is the time (or phase duration) required to depolarize a nerve fiber when the peace current is twice rheobase?

Chronaxie

When amplitude is twice rheobase and the phase duration is slightly greater than chronaxie, what is the outcome?

The result will be greatest comfort for the patient

What is the number of pulses or cycles generated per second?

Frequency

What does frequency affect?

The number of action potentials elicited during stimulation

Higher frequency leads to?

Summation

What is summation of a motor neuron?

Tetany

What is the rate limiting factor of the number of impulses that can be generated by a nerve?

Absolute refractory period

At what frequency does temporal summation occur?

50 pps

(Target to cause tetnay for both slow and fast twitch muscles)

What is it when the stimulation at high frequency near refractory period of the sensory nerve causes inhibition?

Wedensky`s inhibition

What is the frequency of Wednesdays inhibition for sensory nerves?

Over 1000 Hz

What does wedenskys inhibition (frequency over 1000 Hz) result in?

Anesthesia between the electrodes

(Pain growers away, it stops conducting signal)

What is stop and go pulses?

Treatment frequency

What is it when it goes non stop?

Generator frequency

What level of generator frequency do we use?

Medium frequency generators

(1,000- 10,000 Hz)

How many leads must there be to complete a circuit?

Two leads

Leads can be what?

Split or bifurcated

What will unequal size electrodes result in?

Current concentrates in smaller one, giving the perception of increased intensity

What is the result when you place the pads close together?

Current most concentrated in superficial tissues

What is the result when you place the pads far apart?

Current goes deeper through nerve and blood vessels

What is the minimum distance apart for the electrodes?

Minimum 2 inches

How can you minimize the resistance?

Reduce skin-electrode resistance

How can you reduce the skin-electrode resistance?

Minimize air-electrode interface

Keep electrodes clean

Adequate moisture on pages

Use largest electrodes practical

What is it when 2 or more unequal sized electrodes are used?

Monopolar electrode configuration

In monopolar electrode configuration one is the __________ and one is the _________ electrode

Active

Dispersive

What are 3 reasons for the monopolar electrode configuration?

Leads placed far apart= deeper penetration

Greater comfort at dispersive pad when using point stimulator

Create electrical field with specific polarity

What is the bipolar electrode configuration?

2 equal size electrodes placed over treatment site

What is the most common use of bipolar electrode configuration?

TENS (transcutaneous electrical nerve stimulation

Quadripolar configuration is often used with what current?

Interferential current

Describe quadripolar configuration

Two separate medium frequency currents are used with electrodes placed as cross currents

-4 pads set up in criss crossing pattern for the 2 channels

Where is the current with a quadripolar configuration

Interfered within the center of the 2 currents

-electricity comes together in the middle of the 4 pads