Pain Control - TENS Flashcards
what does TENS stand for
transcutaneous electrical nerve stimulation
what type of stimulus is TENS considered? what could change this?
external
TENS with dry needle
what is electroanalgesia
electrical stimulation for pain modulation
how do analgesic effects occur
electrical stimulation to peripheral/central NS
– more so focused on peripheral
what can be manipulated in TENS units
intensity
pulse rate
pulse width
what are dorsal column stimulators
electrodes inserted in dorsal column that are used to modulate pain
what is typically manipulated to avoid accommodation
frequency or pulse width
what type of device is a TENS unit? why does this matter?
its a class 2 medical device
– patient must be issued and instructed by medical professional on how to use for reimbursement to occur
explain education in relation to TENS administration
obviously how to use it, but also how to control intensity to achieve desired analgesic pain effects
modes of TENS application
conventional
burst mode
acupuncture like
brief intense
what is the differentiator between conventional vs acupuncture or burst mode TENS
conventional = sensory response
ac/burst = sensory and motor response
explain the practicality of conventional TENS
very much so, most common type used
what does conventional TENS stimulate
sensory level via large sensory fibers
how is accomodation possible with conventional TENS
modulation of intensity or decreased rate
explain the effectiveness of conventional TENS
effective as long as the stimulus is applied
what is the rate of conventional TENS
high = 60-150 pps
explain the width of conventional TENS
narrow = 50-100 microseconds
describe intensity related to conventional TENS
comfortable tingling sensation without muscle contraction
explain duration of conventional TENS treatment
until pain relief is achieved, should be within 15-20 min and less than 30
where to place electrodes when doing conventional TENS
on painful area
indications of conventional TENS
acute/chronic pain
when applying conventional TENS and you notice a motor response, what can be done?
increase pps
explain why intensity may change during conventional TENS treatment
as patient gets more comfortable with stimulus, intensity can be increased
if too intense, can move electrode away from area to decrease the subjective feeling of “intensity” (not the actual value)
remind me about the gate control theory… what cells are involved
a beta fibers are activated
blocking a delta and c fiber
explain rate related to burst mode TENS
high rate stimulating current administered in bursts at a low rate
current = 100pps
bursts = 1-4pps
explain pulse duration of burst mode TENS
0.1-0.3 msec
explain treatment time related to burst mode TENS
20-45 minutes
what should be visually observed during burst mode TENS treatment
muscle contractions
explain effects of burst mode TENS and why?
effects can last several hours due to release of systemic endorphins
where to place electrodes in burst mode TENS
acupuncture points
motor points
trigger points
indications of burst mode TENS
sharp
chronic
severe pathologic pain
explain what acupuncture like TENS stimulates
small diameter nerve fibers
C-fibers primarily
explain the effects of acupuncture like TENS application and why?
relatively longer period of relief due to endorphin release / liberation of endogenous opiates
indication of acupuncture like TENS
chronic pain syndromes
explain rate and width of acupuncture like TENS
low rate = 2-4 pps
wide = 200 microseconds
explain intensity related to acupuncture like TENS
as high as patient can tolerate
- looking for visible contraction
electrode placement in acupuncture like TENS
“acupuncture points”
“well damn, you must be in a doctorate program or something”
explain rate and width of brief-intense TENS
high rate = >100-150 pps
wide = >150-200 microseconds
explain intensity related to brief-intense TENS
noxious
– as high as the patient can tolerate
looking for muscle contraction
explain electrode placement in brief-intense TENS
acupuncture points
motor points
trigger points
what type of muscle contraction is looked for during brief-intense TENS
tetanic muscle contraction
explain on and offtime related to brief-intense TENS
on = 5 sec to 1 min per pt tolerance
off = 1-5x on time
explain treatment duration of brief intense TENS
as tolerated, max of 15 min
explain what brief-intense TENS can also be used for
will produce a brief surface analgesia
— can be used in more painful procedures to accommodate pain signal
explain tetanic muscle contraction and its purpose
muscle will maintain a contraction without fatiguing
- causes endoprhin/enkephalin release that will modulate pain response via descending pathways
explain CNS stimulation related to brief-intense TENS
will stimulate periaqueductal gray region of midbrain via a-delta and C fiber afferents
“Bypasses gate control theory”
explain the difference in stimulation necessary when comparing wide dynamic range vs nociceptive specific neurons
wide range = a beta fiber stimulation
nociceptive = a-delta / c-fiber stimulation
in general, where do electrodes need to be placed
in place where patient can access them and reapply if necessary
explain skin resistance to flow in relation to distance between electrodes
direct relationship
- want to have at least the size of another electrode between
explain why bracketed electrode placement would be indicated
larger treatment area
clinical use of TENS
orthopedic pain
MSK pain
decreased pain associated with inflammation
acute post-op pain
neurological pain
OB/GYN associated pain
precautions of TENS
do not submerge in water (no shit)
change in pressure against pads will change intensity of current
educate patient that TENS should be used as much and as little as needed
do not use while sleeping
explain supra-sensory TENS
application of tens that is slightly above sensory level
– aim to release endorphins and enkephalins in conjunction with gate control theory
explain supra-sensory dosage
dose dependent
higher amplitude/intensity = higher analgesic response
types of opioid receptors
delta
kappa
mu
explain frequency associated with mu-opioid receptor stimulation
low frequency = 1-10 Hz
explain frequency associated with delta-opioid receptor stimulation
high = 50-150 Hz
explain how prescription opioids affect TENS application
will bind with Mu receptors
– making TENS ineffective at lower frequencies, will need high frequency
what opioid receptors does TENS stimulate
MU / Delta
explain what amplitude-dependent dosage is? why is it clinically important?
higher amplitude tolerated by patient = greater analgesic effect
apply amplitude to “noxious level” then decrease back to “strong but tolerable”
– will naturally increase threshold of initial “noxious” intensity for treatment
what does intensity depend upon
pulse rate
pulse width
area of application
noxious TENS rate and width paramenters
high rate = 150 pps
high width = 400 microseconds
on/off time of noxious TENS
10 sec on & 10 sec off with a 2 second ramp
treatment time of noxious TENS
15-20 min total
explain VAS scores related to noxious TENS
hit a 9/10 level initially, then reduce to a 5-7/10 for the actual treatment
electrode placement related to noxious TENS
surrounding painful area
considerations of noxious TENS
educate on anticipated risks/benefits
— typically for patients with central/peripheral sensitization of chronic pain syndromes
explain outcome pain measures associated with TENS interventions
should be collected during standardized activity that causes/onsets pain
how to objectively assess pain measures
pressure algometer
when should TENS be included
during functional activities and components of exercise
