TENS Flashcards
6 Characteristic of TENS
1) It is an application of low voltage electrical stimulation for pain control.
2) Stimulates sensory receptors
3) Does not generally “cure the pain” it manages it
4) Alternative therapy to medication
5) Allows the client to perform ADL’s & Home exercise
6) Increases the quality of life for those who have chronic pain.
3 Pieces of TENS equipment
1) Device: portable and clinical
2) Lead wires: polarity of wire (red or black) does not matter with TENS
3) Electrodes: adhesive v. carbon. Uses 2 or 4 electrodes.
Concept of Amplification
Pain is influenced by physiological, psychological, behavioral, cognitive, affective, and environmental factors.
3 Types of pain
1) Acute: rapid/sudden onset. Sympathetic response- fight or flight.
2) Chronic: More diffuse, all consuming, affects function; greater than 30 days.
3) Referred: in an area other than original injury sit. Hypersensitive areas; pain generally in the fascia.
3 Characteristics of Melzack & Wall’s Gate Theory 1965: Sensory Theory of TENS
1) Nocioceptive (pain) nerve fibers are C fibers which are poorly mylenatied and therefore travel slowly.
2) Sensory nerve fibers are A-beta fibers of Alpha A fibers which are highly myelinatied fibers and travel faster to the hypothalamus.
3) Competition of the two fibers result in sensory stimulation blocking the lesser myelinated pain fibers.
4 Characteristics of the Endorphin Theory: Motor level theory of TENS
(must create a twitch)
1) Electrical stimulation increases levels of endorphins in central and peripheral nervous system.
2) TENS stimulates motor nerve which facilitates release of endorphins.
3) Believers of this theory feel the analgesic effect is systemic and long lasting.
4) Requires a minimum of 20-30 min of TENS to get the endorphin release.
Acupuncture Theory
TENS alters flow of energy
Myofascial Theory
TENS stimulated local vasodilation which alters trigger point to decrease pain.
A TENS sensory technique
Conventional TENS
good for pts. w/ sharp well defined pain
Conventional TENS Pulse Frequency
50-100pps
Conventional TENS Pulse Duration
50-100 micro-seconds
Conventional TENS Tx. Time
15-30 min, all day, or when having pain (prn)
Conventional TENS pulse amplitude
(Dial) Turn up until pt. feels a tingling, tapping, or pins & needles, without a muscle twitch.
A TENS motor or acupuncture technique
Low Frequency TENS
Good for more diffuse, throbbing, burning pain
Low Frequency TENS pulse frequency
1-4pps
Low Frequency TENS pulse duration
150-200 micro-seconds
Low Frequency TENS tx. time
30-45 minutes
Low Frequency TENS pulse amplitude
Place electrode over motor point: turn up until a muscle gets a twitch
A TENS that applies brief intense stimulation.
Noxious TENS
Rarely used because it is very uncomfortable
Very low pulse frequency and duration.
Hold on usually w/ a probe stimulator 20 seconds over point- very aggressive, high skill level.
Modulation Concept
Pts. will accommodate over time if left on continuous setting. Once TENS set up need to choose an alternate setting (i.e. modulation, burst) which will deliver the stimulation in a random fashion to reduce accommodation.
Electrodes
Looking to chose the correct size to achieve specificity of muscle and enough penetration.
Carbon Electrodes
Need gel or wet sponge as transmission medium
Polymer Self Adhesive Electrodes
Can re-use; watch for loss of stickiness. Rehydrate and reapply to plastic between use, store in ziploc pouch. Too old: creates skin problems due to uneven current density.
Disposable Electrodes
Like a band-aide, readhesive is not great, one time use.
Electrode sizes
1”, 2”, 3”
Can cut down to 2” - most common w/ UE
Electrical current per unit area
Current Density
The smaller the electrode the higher the current density (delivering same amount of current but to a smaller area)
3 Characteristics of Small Electrodes
1) greater current density so may not need to turn amplitude up as far to get a response.
2) Targets the stimulation and therefore cuts down on overflow to adjacent tissue.
3) Increase chance of burning or galvanic response if less than 1”
3 Characteristics to Electrode Placement Choices
1) Identify the area of worst pain and place one electrode there and one proximal.
2) Determine the sensory dermatone pathway and place electrodes within the dermatone, at least one proximal.
3) Over a motor point of acupuncture paint (use a chart)
5 Patterns of Electrode Placement
1) Proximal: Between brain and pain
2) Parallel: On either side of an incision site or scar
3) Crossed Method: use of 4 electrodes on 4 corners w/ the worst pain in the center
4) Unilateral, linear, and overlapping with distal point.
5) Contra-laterally: trait opposite side: used to treat phantom pain or RSD pt.s who can’t tolerate.
What occurs when electrodes are placed to close
They get a higher current density at surface and therefore create a skin reaction.
Penetration depth is directly related to the distance of the electrodes (if you spread them apart you get a deeper penetration)
What creates a resistance to current
Dirt, sweat, lotion.
Get in the habit of cleaning the skin.
Hair (shave)
Dry skin, poor contact/old electrode.
6 Common uses for TENS
1) Acute Chronic Pain
2) Phantom limb pain
3) Post operative pain
4) Obstertic Pain
5) Neurological pain: Shingles
6) Potential Painful Tx’s. (?)
Contraindication and Precautions
Follow general electro-modality
TENS Application
Position in a place of relaxation, ask questions, inspect skin, remove lotions that limit penetration. Assess pain level before tx.
Explain procedure, describe the sensation, & potential benefits.
Place elecdtrodes, set to continuous, select parameters (pulse frequency and pulse duration)
Turn machine on slowly increasing the amplitude until pt. reports a sensory response.
Adjust to one of the other settings (burst, modulate, etc.) to prevent accommodation.
Evaluate effectiveness with a pain scale and or ability to complete a fx. task.
