TENS Flashcards
what does TENS stand for?
transcutaneous electrical nerve stimulation
what is TENS?
-pulsed current
-low freq current
what is interferential therapy?
-alternating current - uses 2 medium freq currents to create a low freq current
-less commonly used now
what physiological effect does nerve stimulation of a motor nerve at 10-50 hz have?
a muscle contraction
what effect does stimulating sensory nerve (non-pain) fibres at a freq of 90-130 Hz have?
-sensory stimulation
what is the pain gate theory?
when a non noxious stimuli is applied - it can inhibit the transmission of pain from a delta and C fibres
what is descending pain inhibition?
-use of lower freq stimulates a delta and c fibres
-stimulation of a delta and C fibres activates the opioid mechanisms
-this leads to descending inhibition of pain
what are examples of TENS parameters?
-pulse or frequency
-amplitude
-pulse duration
-burst mode
-modulation
what is amplitude influenced by?
-size of electrode
-placement of electrode
-patients tolerance
-area
why is cyclical variation good?
as it is believed to help prevent adaption of the nerves to the current
what are examples of different types of tens?
-conventional TENS
-acupuncture like TENS
-intense TENS
-burst TENS
what is the aim of conventional TENS?
to selectively activate the large diameter sensory fibres without activating the pain fibres or motor fibres
-rapid onset but short acting pain relief
what is the aim of acupuncture like TENS?
-selectively activate the small diameter alpha delta and c fibres
what is brief intense TENS?
-to produce rapid pain relief by activating the alpha delta fibres at an intensity that is just tolerable to the patient
what is burst TENS?
a conventional TENS, interrupted by bursts of 2-5 bursts / second
-higher than conventional
which tens should you use?
-conventional is commonly tried first
-acupuncture like is used frequently for chronic pain (for descending pain inhibition)
-brief intense and burst tens used less frequently
what are contraindications to using TENS?
-undiagnosed pain
-lack of normal sensation
-pacemakers / cardiac arrythmias
-malignant tumours
-over the carotid sinuses
-pregnancy
-epilepsy
-people who have an allergic reaction to electrodes
what are pre-cautions for use of TENS?
-cardiac disease
-impaired sensation
-impaired cognition
-skin irritation
-open wounds / fragile skin
what are adverse effects of TENS?
-headache
-electrical burn
-hypotension if electrodes are placed over cervical spine
what important test must be done before TENS treatment?
-sharp blunt test
-w/ pts eyes closed
-if pt cannot tell difference between sharp and blunt, then sensation is impaired and TENS is not appropriate
what are indications for TENS?
-acute pain eg post injury, post op
-chronic pain eg OA, RA]
-labour pain
what 4 factors is TENS effectiveness is affected by?
-type of application
-site of application
-treatment duration of TENS
-optimal freq and intensities
when is TENS used in labour?
-used in 1st and 2nd stage of labour
-specifically designed obstetric TENS has a boost control for contractions
