10-10a Intro to Clinical Uses of Electrotherapy I

Question 1

What are the uses of Estim?

Answer 1

Neuromuscular dysfunction – NMES/FES

Pain - TENS

Wound/tissue healing - HVPC

Delivery of Pharmacological agents – Iontophoresis

Electric Muscle Stimulation (denervation) – EMS

Edema management

Evaluate nerve and muscle injury - NCV testing

Question 2

What are the uses of Estim?

Answer 2

Neuromuscular dysfunction – NMES/FES (used to get stronger/improve m. control)

Pain - TENS

Wound/tissue healing - HVPC

Delivery of Pharmacological agents – Iontophoresis

Electric Muscle Stimulation (denervation) – EMS

Edema management

Evaluate nerve and muscle injury - NCV testing

Question 3

What are the three types of electrical currents?

Answer 3

Direct Current, Alternating Current, and Pulsatile Current

Question 4

What is DC?

Answer 4

Uninterrupted flow of charged particles

Moves from negative to positive

Question 5

What is AC?

Answer 5

Flows from positive to negative repetitively without breaks

Question 6

What is pulsatile current?

Answer 6

Space between the pulses

Monophasing (all positive) or biphasing (like alternating current: positive and negative

Question 7

What are the three uses of Estim?

Answer 7

sensory (pain), motor (pain and strengthening), noxious (pain)

Question 8

What is charge measured in?

Answer 8

Coulombs

Question 9

What is Current measured in?

Answer 9

Amperes

Question 10

What is voltage measured in?

Answer 10

volts

Question 11

What is resistance measured in? What is it for?

Answer 11

ohms

DC

Question 12

What is impedence measured in? What is it for?

Answer 12

ohms

alternating current/pulse current

Question 13

What is capacitance? measured in?

Answer 13

Farads

Question 14

What makes copper conductive?

Answer 14

metals with one valence electron can share their one valence electron easily

Question 15

What does charge do to the body?

Answer 15

Provide charge on either end of electrodes that changes polarity of ions

Question 16

What is current?

Answer 16

The movement of charged particles through a conductor in response to an applied electrical field

how fast the electrons are moving

1 Amp = 1C of charge/sec

Question 17

What is voltage?

Answer 17

potential difference or electromotive force (EMF); a driving force that makes charged particles move; change in electrical potential energy b/w two points in an electric field/unit of charge

how much potential to drive the flow of electrons (9V battery has less potential difference than 12V battery)

1 volt = 1 Amp of current containing 1 ohm of resistance

Question 18

Voltage in hourglass

Answer 18

How much sand at the top to flow down

Question 19

Current in hourglass

Answer 19

how fast the sand flows down

Question 20

Resistance

Answer 20

Opposition to current (movement of charge particles); Flow of current inversely proportional to resistance

Question 21

What is Ohm’s Law?

Answer 21

I = V/R

Question 22

resistance is equal to:

Answer 22

Rho * (length/cross-sectional area)

Question 23

What is Ro?

Answer 23

Rho= inversely proportional to water content

Question 24

What is Ro?

Answer 24

Rho= inversely proportional to water content
resistivity in biological tissues is inversely proportional to water content
Virtually all resistance at electrode-skin interface

Question 25

What is Ro?

Answer 25

Rho= inversely proportional to water content resistivity in biological tissues is inversely proportional to water content Virtually all resistance at electrode-skin interface

Question 26

What does skin and fat do to electrical current?

Answer 26

provides resistance

Question 27

What happens when resistors are in parallel?

Answer 27

1/resistance added for each resistor

Question 28

Between each electrode, what is providing resistance?

Answer 28

skin and fat in series (primary form of resistance), then n., m., and bone/other forms of resistance are in parallel

Question 29

While using NMES, 100 Volts meet 4.467k Coulombs. | What is the current reaching the peripheral nerves that innervate the m.?

Answer 29

V = IR I=V/R 0.02 A or 20mA = 100 V/ 4,467 C

Question 30

What are the two applications of Ohm's Law? | How can resistance change in a patient?

Answer 30

Constant Current Devices: Current constant despite R changes Constant Voltage Devices: Constant V despite changes in R Incision, perspiring, swelling, dying out of the electrode

Question 31

What would happen if imedance suddenly drops from 4.476 kCoulombs to 1 kCoulombs with a constant voltage device (100V)?

Answer 31

I = V/R I = 100V/1000C I = 0.1 A or 100mA Current is higher

Question 32

What would happen if imedance suddenly drops from 4.476 kCoulombs to 1 kCoulombs with a constant current device (0.02 A)?

Answer 32

``` V = IR V = 1000 Coulombs * 0.02 A V = 20 V ```

Question 33

Where does current flow? How does this affect current flow when there is a break in the skin? When electrodes touch? When the electrodes are dry?

Answer 33

the path of least resistance Current becomes much greater due to less resistance where the break of the skin lies Brings a lot of current through a really small area Sweat adds resistance; dryness prevents sticking and can also cause resistance

Question 34

What is the main reason for DC stimulation? What is this used for?

Answer 34

iontophoresis: Administers medication transdermally Uses the polarity of drugs to push it into the tissue

Question 35

What are the therapeutic effects of DC current on the body? Effects when applied in excess?

Answer 35

therapeutic flow of ions to change polarity, local increase in blood flow to restore pH blistering, chemical burns, reaction is more caustic to skin

Question 36

What is the direction of flow of ions in regards to a black cathode and a red anode

Answer 36

Electrons flow towards the "negative" cathode and away from the anode "positive"

Question 37

Contraindications for EStim

Answer 37

``` Cardiac problems-pacemakers/ICDs (less worrying for LE) Electronic devices Carotid Sinus Larynx Pregnancy (low back/abdomen) Broken/damaged skin DVT (local) CA (local) Recently radiated tissue Chest (cardiac issues) Neck/head (seizures) On or near eyes ``` mostly considered risk vs reward don't do it over life sustaining organs

Question 38

What are precautions for Estim?

Answer 38

``` Open skin lesions Skin conditions Open epiphysis Mental status Reduced sensation Allergies Metal implants Cognitive/communication impairments ```

Question 39

What Estim requires specialized training?

Answer 39

Transcranial Direct Current Stimulation | Reproductive organs/genitalia

Question 40

What does a bipolar set up consist of?

Answer 40

two channels | two electrodes

Question 41

What does a quadripolar set up?

Answer 41

Four electrodes

Question 42

Unipolar setup?

Answer 42

one active electrode/ultrasound head along with a large dispersive electrode to find source of pain not commonly used