E-stim

Question 1

Basic concepts of electrical current

Answer 1

• all matter is composed of ions that posses electrical energy
• ions move from an area of higher concentration to an area of lower concentration
• the more ions an object has, the higher the electrical postential

Question 2

Electrical potential

Answer 2

Electrical force capable of propelling particles from higher to lower energy levels

Question 3

Electrical current

Answer 3

The net movement of electrons

• always move from higher to lower concentración
• the rate at which current flows is measured in amperes (therapeutic purposes mA or microA)
• potential difference between 2 points makes electromotive force that provides movement of electrons (volt)

Question 4

Voltage

Answer 4

The force resulting from an accumulation of electrons at one point in the electrical circuit
- usually corresponds to the deficit at another point

Question 5

Conductors

Answer 5

Materials that permit free movement of electrons

Question 6

Watt

Answer 6

Amount of energy or power produced

Question 7

Electrotherapeutic currents

Answer 7

1. DC: monophasic or Direct/Galvanic unidirectional flow of charged particles
2. AC biphasic or Alternating bidirectional flow of charged particles (reversing polarity)
3. PC polyphasic or Pulsatile an alternating current that is modified to produce 3+ phases in a single pulse; pulses are interrupted and repeated

Question 8

Pic

Answer 8

Pic

Question 9

Continuous mode

Answer 9

Uninterrupted flow of current

Question 10

Interrupted mode

Answer 10

Intermittent cessation of flow for a second or more

Question 11

Surge mode

Answer 11

A gradual increase/decrease in intensity over a period of time

Question 12

Ramped mode

Answer 12

A gradual rise of intensity (set time), then.a maintained intensity (for a set time), followed by either a gradual decrease or abrupt decline in intensity

Question 13

Physiology

Answer 13

• properties of excitable cells
• electrical action of mm and nerve
• motor point
• types of mm contraction

Question 14

RMP

Answer 14

Resting membrane potential

• the cell membrane is more permeable to K+ compared to Na+ and negatively charged proteins
• RMP is -60 to -90 mV for excitable cells

Question 15

AP

Answer 15

Action potential

• generated when the influx of Na+ causes a deduction in RMP (depolarization)
• K+ channels fully open and Na+ channels close (repolarization)
• K+ remain open long enough to repolarization membrane to 10-20mV < RMP (hyperpolarization)

Question 16

Propagation of AP

Answer 16

AP movement along surface of cell

Question 17

Electrical actions

Answer 17

ES characteristic required to initiate excitable cell depolarization

• amplitude or intensity of the stimulus must be great enough to cause membrane potential to be lowered to threshold levels
• duration of stimulus must be long enough to produce depolarization
• the rate that the current rises to peak intensity should be fast enough to prevent accommodation

Question 18

Motor point

Answer 18

Arena of greatest excitability on the skin surface

• where the smallest amount of current generates a mm response
• located at/near where the motor nerve enters the mm for an innervated mm
• located over the mm dismally, or toward the insertion, Ford enervated mm

Question 19

Brief mm twitch or contraction

Answer 19

Each stimulus is produced by a low-frequency pulse (1-10 Hz)

Question 20

Tetany

Answer 20

Increasing the number of stimuli (frequency) will progressively fuse the individual mm twitches to a sustained contraction

Question 21

Vermicular

Answer 21

An asynchronous or wormlike mm response is noted in denervated mm
- or when almost on motor point but not quite

Question 22

E-stim indications

Answer 22

Pain modulation 
Mm guarding/spasm decrease 
Mm strengthening/re-edu
ROM increase
Swelling/inflammation decrease
Wound healing
Fracture healing
 Transdermal drug delivery

Question 23

How does e-stim work

Answer 23

Uses an electrical current to creat a physiological change by targeting afferent nerve pathways to include sensory, motor, and pain fibers

Question 24

How does e-stim cause a change in the nerve fibers of the PNS?

Answer 24

Action potentials
- the flow of charged particles depolarizers nerve membranes producing an action potiential with enough simulation to cause a physiological change

Question 25

E-stim precautions

Answer 25

``` Skin- irritation, wounds, sensation Cancer Cognition decrease Cardiac decrease Hypo/hypertension Pregnancy Bleeding disorders Edema Excessive adipose tissue ```

Question 26

E-stim contras

Answer 26

``` Pacemaker Epilepsy Active bleeding/infection Donut preggy belly Dont place over: Carotid Thrombosis Eyeball Phrenic nerve Bladder stimulator Pharyngeal/laryngeal mm Superficial metal implants Transcerebral/thoracic regions ```

Question 27

E-stim adverse reactions

Answer 27

- electrical burns - skin irritation from adhesive - pain - sensitivity to e-stim (rash, redness)

Question 28

TENS

Answer 28

Transcutaneous electrical nerve stimulation Indications: pain control and modulation

Question 29

Gate control theory

Answer 29

Stimulation of non-noxious fibers will interfere with noxious transmission to the brain to decrease the perception of pain (at the level of the spinal cord)

Question 30

Endogenous opioid system

Answer 30

Stimulation of endorphins bind with opiate receptors to amuse an inhibitory response - occurs with stimulation of motor nerve fibers

Question 31

Amplitude

Answer 31

Intensity: the current strength or voltage

Question 32

Pulse duration

Answer 32

Pulse width: the time to complete one +/- cycle in microseconds

Question 33

Frequency

Answer 33

PPS or Hz. The number of pulses delivered by the ES to the body or number of times the nerve is stimulated in 1 second

Question 34

Therapeutic frequencies of E-stim application

Answer 34

1-10 Hz creates a tapping effect 35-50 Hz creates smooth muscle contraction 80-150 creates a sensory effect

Question 35

TENS pic

Answer 35

Pic

Question 36

Conventional TENS

Answer 36

High rate - Better for ACUTE PAIN conditions. Effects last only as long as stimulation is applied; use various modes to decrease accommodation

Question 37

Accommmodation phenomenon

Answer 37

When an unchanged, constant stimulus is applied this leads to a decrease in nerve excitability with decreased perception of a sensation after a period of time with the same sensory input

Question 38

Low rate TENS

Answer 38

Acupuncture like - better fro CHRONIC PAIN conditions. With increased use, can lead to DOMS. Less accommodation than with high rate

Question 39

Modes of TENS

Answer 39

1. Continuous: frequency, pulse width, and intensity stay as set without change 2. Burst: gradual increase in intensity which peaks, then decreases in intensity and cycles on/off 3. Modulated: any pattern variation of frequency, pulse width, intensity, randomly set by the unit

Question 40

Pad placement for TENS

Answer 40

- 2-4 pads (size of area) - place pads on or around area of pain - place along a nerve to assist with desensitization - place on trigger point - place along mm fibers (best with acupuncture TENS) - 1 inch apart!