VCU DPT - Agents (Electrical Current for Pain- IFC, PREMOD, SUMMARY PORTION)

what is nociceptive response

nerve fiber stimulation, reponding to stimuli that reaches a harmful intensity

difference in neuropathic and somatoform pain

neuopathic is burning, numbness, tingling

somatoform is psychogenic

- increased, prolonged, caused by mental/emotional/behavioral factors

vsiceral vs deep somatic vs superficial somatic

rank these in terms of easy to locate

vsiceral: dull ache, diffuse

deep somatic: easier to locate than visceral

superficial somatic: easy to localie

what is cute vs chronic pain

acute pain is our bodies warning system, and expectation of resolution

chronic pain is less well defined, with no biologic benefit

what time frame is often used to divide acute and chronic pain

3 months

which of the following pains has no biologic benefit

acute or chronic

chronic

which of the following 4 fibers are 'pain' fibers

a-alpha

a-beta

a-delta

C

a-delta

C

of the two ascending pain pathways, can you say whichi s fast and which is slow

fast: a-delta

slow: C

______ fibers relay fast and well localized pain, and provide us with the withdrawl reflex

_____ fibers are not myelinated, and provide diffuse/dull/ache that moves slower and lasts longer

a-delta

c

label the following as being either

1.a-delta

2. C

a. well localized pain

b. diffuse pain

c. nonmyelinated

d. longer lasting

e. myelinated

f. withdrawal reflex

g. faster

1. a, e, f, g

2. b, c, d

what descending pathways does nocicoeptive stimuli go down

motor/efferent, ventral root

t/f: pain is subjective

true

_________ is not a reflex response, but an opinion

pain

what are the three gates in gate control theory

also can you give me a brief little summary of it

spinal cord

brainstem

prefrontal cortex

e-stim can close a gate through a-beta nerve activation and activating inhibitory inerneurons, or endorphins can modulate the pain

gate control theory states that __________ can be used to activate a-beta nerves to close a gate and activate inhibitory interneurons, whereas _________ is used to modulate pain in spinal cord by binding to opiood receptors

e-stim

endorphin

what is interferential current (IFC)

when there is interference of 2 medium AC frequencies that are DIFFERENT

t/f: IFC is the overlapping/interference of 2 medium AC frequencies that are the same

false

they are DIFFERENT

IFC is delivered through ________ of electrodes from ______ channels in ______ stimulator

2 sets

seperate

the same

does IFC have built in modulation?

yes, with in phase and out of phase

do alternating currents intersect on skin?

yes, you want them to intersect where the pain is

when the currents intersect, two things can happen. describe them

in sync/phase

out of sync/phase

in sync/phase is when frequencies add up and create constructive interference

- two add up essentially

out of sync/phase is when frequencies cancel each other out and create destructive interference

- the two will cancel one another out

match

A. in sync/phase

B. out of sync/phase

1. constrcutive interference

2. destructive interefernece

A <--> 1

B <--> 2

with IFC, the frequencies of the two channels are ________ while the amplitude is ________

different from each other

the same as one another

IFC produces envelopes/bursts of pulses known as ______

beats

what is beat frequency

the difference between the 2 frequencies going in IFC

what is the carrier frequency? what is beat frequency?

which one can PT impact

carrier frequency is the frequency the machine sets

beat frequency is difference in two channels

beat frequency: PT can change the non-carrier frequency, impacting beat

most machines have carrier frequency set at _______ Hz

4000

IFC usually uses (sensory level or motor level) but CAN be (sensory level or motor level)

sensory level

motor level

why may IFC may have more of a circulatory affect than TENS

it tends to go deeper

(evidence mid tho lowkey)

is the evidence for IFC great about circulatory effect and stimulating superficial+deep tissue?

if not, what is evidence good for on IFC?

not really

good for helping pain!

is IFC modulation good

its not the best evidence but it will not make it bad

what are the two top ways to modulate IFC and explain them

sweep

- the machine will vary the beat frequency

- evidence only that it will not make worse

vector scan

- alters amplitude on one/both currents

- ie agitator on washing machine

- may provide stim to greater area

with IFC modulation,

_________ varies the beat frequency

while

________ will alter the amplitude on one/both currents

which one may provide a stim to a greater area than expected

sweep

vector scan

vector scan

the beat current is created where the frequencies meet. the area where this happens is called the ________

zone of interference

IFC is ___________ comfortable than other waveforms

possibly more

medium frequency/low amplitude at the skin

IFC may affect _______ and _______ area compared to other ESTIM

larger and deeper

__(TENS/IFC)___ may provide superior pain relief, but you can use the other if patient dislikes the sensation of it

TENS

what are some indications for IFC

pain from swelling

MSK pain

chronic inflammatory conditions

chronic LBP

is IFC always quadripolar

yes

do IFC channels always cross

yes

how far apart should electrodes be (IFCM+ TENS)

2 inches

parameters for IFC:

carrier frequency

beat frequency

- high

- low

vector scan

intensity

treatment time

carrier: 4000 Hz default

beat frequency

- high: 80-150Hz (sensory)

- low: 1-10 Hz (motor)

automatic 100% vector scan

strong but comfortable intensity

15-20 minutes time

what is PREMOD

alternating current of medium frequency

a single circuit that uses 2 electrodes

Premod uses the same waveform as _______

IFC

only needs 2 electrodes tho

how does Premod have the same waveform as IFC

the amplitude will automatically increase and decrease

compared with IFC, premod....

may not go as ______ into tissue

may not cover ________ area

is better for _______ area

deep

as large of

smaller

which of the following statements is true regarding IFC

a. modulation is not possible

b. requires use of 2 electrodes

c. interference of 2 frequencies causes beat frequency

d. the carrier frequency is the therapeutic current

a. F; vector scan and sweep

b. F; 4

c. TRUE

d. F; beat frequency is

what does evidence say about TENS use

that it can help decrease pain, esp in the clinic. Might be placebo and the specific cause not known, but it can

what does evidence say about TENS vs IFC

that they both improve pain and functional outcomes, and there is no major difference between them

when would you use TENS vs premod/IFC

use TENS first, and if patient does not like it then use either

- premod (if area is small)

- IFC (if area is large)

contraindications for estim (all 3 types)

cardiac pacemakers

unstable arrhythmia

tumors

over head/neck/chest

active DVT

infection/damaged skin

LOW RATE/BURST TENS SHOULD NOT BE USED IF MUSCLE TWITCH IS CONTRAINDICATED

is there a contraindication specific to TENS

yes

low rate/burst should NOT be used if a muscle contraction is not allowed via unstable site

- muscle twitch can be dangerous

if patient does not like low rate/burst TENS, what do you do instead

use IFC

what are some precautions to estim (all 3) (really long general list)

impaired sensation

impaired circulation

impaired mentation

skin disease

active epiphysis

neuropathy

cardiac disease

what are 3 types of TENS

conventional TENS

low rate TENS

burst mode TENS

_____ TENS uses short duration, high frequnecy pulses to reduce pain sensation

_________ TENS uses low frequency pulses of longer duration

_________ TENS has its current delivered in bursts of pulses

conventional

low rate

burst mode

____ TENS uses gate control theory

_____ TENS uses endogenous opiods

high rate

low rate

______ has a field of intereference that is made by crossing 2 medium frequency currents to stimulate pain relief

(what is primary mechanism it uses)

IFC

gate control theory

_____ mimics IFC with 2 electrodes/leads

premod (premodulation)