Intro Electro

Question 1

conduction flows in ____, convection flows in ____

Answer 1

conductors

fluids or gases

Question 2

Current recorded as

Answer 2

I, amperes

Question 3

Postive ions =

are attracted to ____ which are

Answer 3

cations, cathode, negative

Question 4

Negative ions =

attracted to__, which are

Answer 4

anions, anode, positive

Question 5

T/F current flows pos to neg

Answer 5

no both directions

Question 6

coulomb

Answer 6

charge carried by ampere for one second

basic unit of measured charge

Question 7

ampere or amp

Answer 7

rate of flow of current

measures current intensity

Question 8

volt

Answer 8

energy difference between two physical points

inert needed to move a coulomb between 2 points

Question 9

Resistance measured in

Answer 9

ohms

Question 10

Ohms Law

Answer 10

voltage related to resistance and current

Voltage = current x resistance

Question 11

Watt

Answer 11

rate of converting energy (power)

Question 12

Is skin homogenous

Answer 12

no

Question 13

Why dry epidermis impede electric current

Answer 13

Ohmic resistance
capacitive reactance
inductive reactance

Question 14

Skin resistance depends on

Answer 14

dry or wet
warm or cold
pulse duration
current intensity

Question 15

impedance

Answer 15

resistance

Question 16

Impedance inc or dec electrode off the skin

Answer 16

increase

Question 17

in practice do we use constant voltage or current

Answer 17

voltage

Question 18

Biological effects of applied electrical charges

Answer 18

Electrochemical (new compounds)
electrophysical (stimulate)
electrothermal (heat)
cellular signalling (cell behaviour)

Question 19

biolelectricity

Answer 19

all living cells generate it
membranes have voltage gradients
essential for healing

Question 20

4 applications of therapeutic modalities

Answer 20

pain
performance (facilitate or inhibit)
inflammation/healing
flexibility ROM

Question 21

three ways tissue damage from current happens

Answer 21

chemical burns
prolonged mm contraction (heart)
high density cause tissue heating

Question 22

macroshock

Answer 22

current through skin

1mA for 1 sec

Question 23

microshock

Answer 23

current through heart

Question 24

how many mA may be fatal

Answer 24

100

Question 25

how many uamps may cause ventricular fibrillation

Answer 25

20

Question 26

variable that determines severity of shock

Answer 26

current

Question 27

how to prevent tissue heating

Answer 27

size of electrodes contact current intensity Low as effectively possible

Question 28

5 contraindications for estim

Answer 28

``` electric devices preg infection seizures cardiac disorders ```

Question 29

can you give equipment to patients

Answer 29

only if the manual says you can

Question 30

4 components of device safety

Answer 30

equipment meets standards 3 pin plug used inspect cord and test it Screen for risks

Question 31

strength duration curve

Answer 31

technique to identify state of injury or mm/nerve

Question 32

SD testing

Answer 32

gets minimal palpable contraction

Question 33

indications for SD use

Answer 33

monitor lesion progress establish pulse duration for treatment establish integrity of tendon when pt can't contract

Question 34

Three concepts for nerve depolarization

Answer 34

intensity pulse duration rise time

Question 35

rheobase

Answer 35

minimum current intensity for perceptible contraction

Question 36

chronoaxie

Answer 36

minimum duration of impulse to produce response

Question 37

small or large diameter depolarize first

Answer 37

L

Question 38

what is stimulated first from skin

Answer 38

AB (sensory) Aa (Motor) Ao (pain)

Question 39

Inactive Red Anode

Answer 39

area near membrane becomes positive | harder to depolarize

Question 40

Active Black cathode

Answer 40

area near membrane more negative | easier to depolarize the nerve

Question 41

normal or denervated mm require longer duration to demoralize

Answer 41

denervated

Question 42

factors affecting outcome of SD curve

Answer 42

``` skin tissue position of electrode pressure humidity oedema ```

Question 43

advantages of SD testing

Answer 43

monitor progress non-invasiev simple high inter rater reliability

Question 44

disadvantages of SD testing

Answer 44

poor repeatibilty unable to localize nerve trunk less valuable for large mm

Question 45

curve of partially denervated mm's

Answer 45

location of kink not signification left to kink = innervated, right denervated fibres curve change 6 wk before clinical changes no recovery by 5 months, poor prognosis