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Therapeutic Electrical Therapeutic Electrical ModalitiesModalities
Learning ObjectivesLearning Objectives
Be familiar with the characteristics of Be familiar with the characteristics of electric modalities that are applied for electric modalities that are applied for therapeutic purposestherapeutic purposes
Identify physiological and therapeutic Identify physiological and therapeutic effects of electric modalitieseffects of electric modalities
Be familiar with contraindications and Be familiar with contraindications and precautions in using electric modalitiesprecautions in using electric modalities
Identify adverse effects for each Identify adverse effects for each modalitymodality
Learning Objectives Cont’d . . .Learning Objectives Cont’d . . .Be familiar with the multiple uses of Be familiar with the multiple uses of electrical stimulation (ES)electrical stimulation (ES)
When given a clinical scenario, be When given a clinical scenario, be able to:able to:– Define goals of treatment with ESDefine goals of treatment with ES– Choose the appropriate device Choose the appropriate device – Select the appropriate parametersSelect the appropriate parameters– Apply the treatment safely and Apply the treatment safely and
competentlycompetently– Modify treatment if neededModify treatment if needed
Therapeutic Electrical Therapeutic Electrical CurrentsCurrents
The application of electrical current to The application of electrical current to the body for therapeutic purposes, the body for therapeutic purposes, such as:such as:– Pain reliefPain relief– Neuromuscular Electrical stimulationNeuromuscular Electrical stimulation– Tissue/wound healingTissue/wound healing– Direct stimulation of denervated Direct stimulation of denervated
musclemuscle
TerminologyTerminology
ChargeCharge
CurrentCurrent
ResistanceResistance
ConductanceConductance
ImpedanceImpedance
Current: Current: – ACAC– DCDC– Pulsatile/pulsedPulsatile/pulsed
AmplitudeAmplitude or or
intensityintensity
Pulsed currentsPulsed currents
Monophasic or biphasicMonophasic or biphasicPulse duration Pulse duration Pulse frequency Pulse frequency
- - interval between pulsesinterval between pulses– can be manipulated independently can be manipulated independently
ModulationsModulations– FrequencyFrequency– AmplitudeAmplitude– BurstBurst
Therapeutic ElectricalTherapeutic Electrical Stimulation Applications Stimulation Applications
Pain ReliefPain Relief
Neuromuscular Electrical Stimulation Neuromuscular Electrical Stimulation (NMES)(NMES)
Tissue/wound healingTissue/wound healing
IontophoresisIontophoresis
Deinervated muscleDeinervated muscle
Transcutaneous Nerve Transcutaneous Nerve Stimulation Stimulation
(TENS)(TENS)
TENSTENS
Stimulates nerve fibers for the Stimulates nerve fibers for the symptomatic relief of painsymptomatic relief of pain
Device applies an electrical signal Device applies an electrical signal through lead wires and electrodes through lead wires and electrodes attached to the patient's skinattached to the patient's skin
Electrode placement varies:Electrode placement varies:– Typically placed in a peripheral nerve Typically placed in a peripheral nerve
distributiondistribution– Locations can be distal or proximal to pain Locations can be distal or proximal to pain
sitesite
How It WorksHow It Works
Gate Control Theory:Gate Control Theory:– Pain signals can be blocked at the Pain signals can be blocked at the
level of the spinal cord before they are level of the spinal cord before they are transmitted to the thalamustransmitted to the thalamus
– TENS stimulates large Ia myelinated TENS stimulates large Ia myelinated afferent nerve fibers that stimulate afferent nerve fibers that stimulate the substantia gelatinosa in the spinal the substantia gelatinosa in the spinal cord, closing the gate on pain cord, closing the gate on pain transmission to the thalamustransmission to the thalamus
Gate Control TheoryGate Control Theory
Physiological Effects of Physiological Effects of TENSTENS
Selective stimulation of large diameter, Selective stimulation of large diameter, myelinated fibresmyelinated fibres– Gate Control TheoryGate Control Theory
Stimulates release of endorphinsStimulates release of endorphins– Endorphin/opiate theory Endorphin/opiate theory
Stimulates release of other transmittersStimulates release of other transmitters– NA, 5-HTNA, 5-HT
?mild heating ?mild heating enhanced healing? enhanced healing?PlaceboPlacebo
Therapeutic uses of TENSTherapeutic uses of TENS
PAIN RELIEF:PAIN RELIEF:– Acute, Subacute, Chronic & Referred Acute, Subacute, Chronic & Referred – MusculoskeletalMusculoskeletal– NeurologicNeurologic– ObstetricObstetric– Oncologic*Oncologic*– Cardiac- anginaCardiac- angina
Modes of TENSModes of TENS
ConventionalConventional
AcupunctureAcupuncture
Burst modeBurst mode
Brief-intense/noxious levelBrief-intense/noxious level
Conventional TENSConventional TENS
High-frequency, low-intensity stimulationHigh-frequency, low-intensity stimulation– most effective type of stimulationmost effective type of stimulation
Amplitude is adjusted to produce Amplitude is adjusted to produce minimal sensory discomfortminimal sensory discomfort
Pain relief begins after 10–15 minutes Pain relief begins after 10–15 minutes and stops shortly after removing and stops shortly after removing stimulationstimulation
Useful for neuropathic painUseful for neuropathic pain
Duration of treatment is 30 minutes to Duration of treatment is 30 minutes to hourshours
AcupunctureAcupuncture
Low frequency, high intensity stimulationLow frequency, high intensity stimulation
Amplitude high enough to produce Amplitude high enough to produce muscle contractionmuscle contraction
Onset of pain relief can be delayed Onset of pain relief can be delayed several hoursseveral hours
Pain relief persists hours after removing Pain relief persists hours after removing stimulationstimulation
Useful for acute musculoskeletal Useful for acute musculoskeletal conditionsconditions
Treatment sessions last 30–60 minutesTreatment sessions last 30–60 minutes
Burst ModeBurst Mode
High frequency stimulation bursts at High frequency stimulation bursts at low frequency intervalslow frequency intervals
Delayed onset of pain reliefDelayed onset of pain relief
Treatment can range 30–60 minutesTreatment can range 30–60 minutes
Brief-intense/Noxious LevelBrief-intense/Noxious Level
Hyper-stimulationHyper-stimulation
High frequency, high intensity High frequency, high intensity stimulationstimulation
It is considered that this mode It is considered that this mode stimulates C-fibers causing counter-stimulates C-fibers causing counter-irritationirritation
Rarely tolerated more than 15–30 Rarely tolerated more than 15–30 minutesminutes
TENS UnitTENS Unit
intensity
Pulse width
timer
mode
frequency
TENS Dosage TENS Dosage
ConventionalConventional Burst modeBurst mode Brief IntenseBrief Intense
80-125 pps80-125 pps 2 bursts per 2 bursts per secsec
125 pps125 pps
60-100 60-100 microsecmicrosec
220-250220-250 250250
Comfortable Comfortable tinglingtingling
Muscle twitchMuscle twitch Strong Strong sensationsensation
Acute pain, Acute pain, fast relieffast relief
Deep, chronic Deep, chronic achy painachy pain
Rapid relief Rapid relief for intense for intense pain pain
Modulation ModesModulation ModesSD: strength-durationSD: strength-duration– Amplitude and width modulate alternately – Amplitude and width modulate alternately –
subtle change in sensationsubtle change in sensation– Allows higher total amount of charge to be usedAllows higher total amount of charge to be used
MW: modulated widthMW: modulated width– StrongerStronger Weaker Weaker
MR: modulated rateMR: modulated rate– Faster Faster Slower Slower
CM: combination modulationCM: combination modulation– Rate and width Rate and width
– ‘‘Diffuse’ sensationDiffuse’ sensation
Electrode placementElectrode placement
Single channel:Single channel:– 2 electrodes2 electrodes
Dual channel:Dual channel:– 4 electrodes4 electrodes
Single channelSingle channel
Surround the painSurround the pain
Over the painOver the pain
Within dermatome/myotomeWithin dermatome/myotome
On trigger points or acupuncture On trigger points or acupuncture points within dermatomepoints within dermatome
Spinal segment: one near spine, Spinal segment: one near spine, other over pain or trigger point other over pain or trigger point within the dermatome/myotomewithin the dermatome/myotome
Dual channelDual channelBracket Bracket
Cross – fireCross – fire
Bilateral placement- both limbsBilateral placement- both limbs
Contralateral: Contralateral: – Phantom pain, skin irritation or woundPhantom pain, skin irritation or wound
General placement: flood the limbGeneral placement: flood the limb– Overlap channelsOverlap channels
PrecautionsPrecautions
Decreased sensationDecreased sensation
PregnancyPregnancy
MalignancyMalignancy
Decreased mentationDecreased mentation
Be careful with repeated applications and prolonged use, adhesives/tape and gel can all cause dermatitis
Make sure the entire electrode has good coverage for gel and don’t use too high a current - can cause electrical burns on the skin!
ContraindicationsContraindications
UNDIAGNOSED PAINANY electronic implant– Some Pacemakers (fixed rate ok Some Pacemakers (fixed rate ok
but rate responsive are affected)but rate responsive are affected)– Cardioverter-defribrillatorsCardioverter-defribrillators
– Some Bladder stimulatorsSome Bladder stimulators Metal implants???
Interferential CurrentInterferential Current(IFC)(IFC)
Interferential CurrentInterferential Current
Another form of TENS:Another form of TENS:– Differs from TENS as it allows deeper Differs from TENS as it allows deeper
penetration with more comfort penetration with more comfort (compliance) and increased circulation(compliance) and increased circulation
AMC AMC (amplitude modified current)(amplitude modified current)
Frequencies interfere with the Frequencies interfere with the transmission of pain messages at the transmission of pain messages at the spinal cord levelspinal cord level
How does it work?How does it work?
2 “medium frequency” currents2 “medium frequency” currents– Low frequency (e.g. TENS) = <1000HzLow frequency (e.g. TENS) = <1000Hz– Medium frequency 1000-10,000 HzMedium frequency 1000-10,000 Hz
2 currents with different frequencies2 currents with different frequencies
Currents ‘interfere’ with one another Currents ‘interfere’ with one another
““Beat frequency” is the difference Beat frequency” is the difference between the 2 currentsbetween the 2 currents
ExampleExample
– C1 = 5000 C1 = 5000 HzHz– C2= 5100 HzC2= 5100 Hz– fixed Beat fixed Beat
frequency = 100 frequency = 100 bpsbps
Indications for IFCIndications for IFC
Urinary incontinenceUrinary incontinencePain reliefPain reliefBlood flow/edema managementBlood flow/edema management– May be effective due to the combination May be effective due to the combination
of pain relief (allowing more of pain relief (allowing more movement), muscle stimulation and movement), muscle stimulation and enhanced blood flowenhanced blood flow
TENS vs. IFCTENS vs. IFC
Physiological effects:Physiological effects:– Depolarize sensory and motor nervesDepolarize sensory and motor nerves
Why not TENS?Why not TENS?– ““Medium frequency” Medium frequency” less skin less skin
impedanceimpedance– Less impedance Less impedance more patient comfort more patient comfort– More patient comfort More patient comfort tolerate higher tolerate higher
amplitude current amplitude current deeper penetration deeper penetration
ContraindicationsContraindications
Same as TENSSame as TENS
Plus: Plus: – With suction cup electrodes:With suction cup electrodes:
BruisingBruising
Cross-infection from spongesCross-infection from sponges
IFC Application IFC Application
Stimulator typeStimulator typeElectrode placementElectrode placement– As precisely as possible so that patient As precisely as possible so that patient
feels the stimulation over the targeted feels the stimulation over the targeted areaarea
Electrode fixationElectrode fixation– Self-adhesive padsSelf-adhesive pads– Non-adhesive taped in placeNon-adhesive taped in place
Coupling mediumCoupling medium– Gel for electrode padsGel for electrode pads
SweepSweep
Beat frequencyBeat frequency is modulated is modulated
Thought to prevent adaptationThought to prevent adaptation
E.g. E.g. – C1 fixed at 5000C1 fixed at 5000– C2 C2 varies varies – Gives a VARIABLE BEAT FREQUENCYGives a VARIABLE BEAT FREQUENCY
Uses of sweepUses of sweep
Sweep ranges: Sweep ranges: – Pain relief 80-150 bpsPain relief 80-150 bps– Muscle rehab 10-100 bpsMuscle rehab 10-100 bps– Edema 1-10 bps (intermittent Edema 1-10 bps (intermittent
muscle contractions)muscle contractions)– Selection of a wide frequency i.e 1-Selection of a wide frequency i.e 1-
100Hz is less efficent + ? Counter-100Hz is less efficent + ? Counter-productiveproductive
Set-Up of IFCSet-Up of IFC
Bi-polarBi-polar
QuadripolarQuadripolar
Quadripolar with scanQuadripolar with scan
Bi-polar methodBi-polar method““Pre-mod”Pre-mod”2 electrodes2 electrodesSingle channelSingle channelCurrent is ‘modulated’ within the machineCurrent is ‘modulated’ within the machineSimilar to TENSSimilar to TENS
Quadripolar methodQuadripolar method4 electrodes4 electrodes
2 channels2 channels
Interference occurs where the fields cross one Interference occurs where the fields cross one another WITHIN the tissuesanother WITHIN the tissues
Cloverleaf patternCloverleaf pattern
Quadripolar fieldQuadripolar field
Quadripolar With ScanQuadripolar With Scan““Automatic vector scan”Automatic vector scan”
AMPLITUDE is varied by the AMPLITUDE is varied by the machinemachine
E.g. E.g. – C1 fixed amplitude/intensityC1 fixed amplitude/intensity– C2 variable amplitudeC2 variable amplitude
Pattern of interference is different Pattern of interference is different
Quad With ScanQuad With Scan
IFC Scan IFC Scan
Uses of scan:Uses of scan:– Large area of treatmentLarge area of treatment– Diffuse painDiffuse pain– Location of pain difficult to Location of pain difficult to
pinpointpinpoint
Neuromuscular Electric Neuromuscular Electric StimulationStimulation
(NMES)(NMES)
NMESNMES
Consists of transcutaneous electrical Consists of transcutaneous electrical stimulation for muscles with or without stimulation for muscles with or without intact PNS, or central controlintact PNS, or central control– More powerful than TENS unitMore powerful than TENS unit
Multiple muscles can be activated in a Multiple muscles can be activated in a coordinated fashion to attain certain coordinated fashion to attain certain functional goals (ambulation, transfers)functional goals (ambulation, transfers)
Types of Muscle ContractionTypes of Muscle Contraction
Voluntary:Voluntary:– Recruits Type I first, then Type 2 Recruits Type I first, then Type 2 – Spatial summationSpatial summation
Recruitment of additional motor unitsRecruitment of additional motor units
– Temporal summationTemporal summationIncreased firing rateIncreased firing rate
– Gradual increase in force Gradual increase in force generatedgenerated
Types of Muscle ContractionTypes of Muscle Contraction
Electrically stimulated Electrically stimulated contraction:contraction:– Reverse pattern of recruitment Reverse pattern of recruitment
Type IIType II Type I Type I
– All motor units fire at onceAll motor units fire at once– Easy to produce fatigueEasy to produce fatigue
Use “Ramp up” for comfortUse “Ramp up” for comfort
Features of NMES CurrentsFeatures of NMES Currents
Pulse durationPulse duration
Pulse rate/frequency: 30-50 ppsPulse rate/frequency: 30-50 pps
Therapeutic Uses of NMESTherapeutic Uses of NMES
Strengthens musclesStrengthens muscles
Motor Re-educationMotor Re-education
Increases ROMIncreases ROM
Enhances enduranceEnhances endurance
Reduces muscle spasm/spacityReduces muscle spasm/spacity
Strength TrainingStrength Training
Recruits maximum numbers of motor Recruits maximum numbers of motor unitsunits
Used if volitional control affected by Used if volitional control affected by – pain pain – reflex inhibitionreflex inhibition– motivationmotivation
Works by overloadWorks by overload fatigue fatigue
Strength TrainingStrength Training
Can improve strength but not as well Can improve strength but not as well as:as:– voluntary contractionvoluntary contraction– ES + voluntary contractionES + voluntary contraction
““high load/low reps”high load/low reps”
Longer rest periodsLonger rest periods
Motor Re-Education Motor Re-Education
Use NMES for:Use NMES for:– Contraction is not readily under Contraction is not readily under
voluntary control (e.g. pelvic floor)voluntary control (e.g. pelvic floor)– Teaching a new action (e.g. tendon Teaching a new action (e.g. tendon
transfer)transfer)– Injured peripheral nerve is Injured peripheral nerve is
regeneratingregenerating
Motor re-educationMotor re-education
Demonstration to convince patient Demonstration to convince patient that contraction IS possible (e.g. that contraction IS possible (e.g. hysterical paralysis)hysterical paralysis)
Enhanced recruitment or timing Enhanced recruitment or timing during a functional movement: during a functional movement: – Functional Electrical StimulationFunctional Electrical Stimulation
Related to a particular task e.g. sit-to-stand, Related to a particular task e.g. sit-to-stand, hand to mouthhand to mouth
Increase ROMIncrease ROM
Stretch contractures *Stretch contractures *
Contract-relaxContract-relax
Facilitate tendon glideFacilitate tendon glide
Break adhesions *Break adhesions *
*Patient may not be able to generate *Patient may not be able to generate sufficient forcesufficient force
Enhance EnduranceEnhance Endurance
Use sub-maximal force over longer Use sub-maximal force over longer period of timeperiod of time
Similar to low load/high reps at the Similar to low load/high reps at the gymgym
Equal work and rest periodsEqual work and rest periods
Promote circulationPromote circulation
Muscle pumpMuscle pump
Prolonged immobilizationProlonged immobilization
Prevents complications from Prevents complications from immobility such as deep vein immobility such as deep vein thrombosis (DVT), and osteoporosisthrombosis (DVT), and osteoporosis
Low load, high repsLow load, high reps
Decrease spasm/spasticityDecrease spasm/spasticity
Stimulate antagonistStimulate antagonist– reciprocal inhibitionreciprocal inhibition
Stimulate agonistStimulate agonist– fatiguefatigue
Stimulate both alternatelyStimulate both alternately
Contraindications and Contraindications and PrecautionsPrecautions
The Big FiveThe Big Five
Carotid sinusCarotid sinus– Venous or arterial thrombosis/ Venous or arterial thrombosis/
thrombophlebitisthrombophlebitis
Areas of skin irritationAreas of skin irritation
Open woundsOpen wounds
Features of NMES CurrentsFeatures of NMES Currents
On timeOn time
Off timeOff time
Rise time/ramp upRise time/ramp up
Fall time/ ramp downFall time/ ramp down
IFC Set-UpIFC Set-Up
Size matters! Size matters! – Small electrodes Small electrodes concentrates the concentrates the
charge charge greater effect greater effect– Larger electrodes Larger electrodes dissipates the dissipates the
charge charge can tolerate greater amplitude can tolerate greater amplitude
Match electrode size to the size of Match electrode size to the size of the musclethe muscle
Set-Up ContinuedSet-Up ContinuedConductivity matters!Conductivity matters!– Skin prepSkin prep
Sensation testingSensation testing
Skin prepSkin prep
– Coupling medium:Coupling medium:Lots of gelLots of gel
Cover ENTIRE electrodeCover ENTIRE electrode
No gel on skin between electrodesNo gel on skin between electrodes
Set-Up ContinuedSet-Up Continued
Location matters!Location matters!– Parallel to muscle fibersParallel to muscle fibers– Over motor pointsOver motor points– Farther apart Farther apart deeper penetration of deeper penetration of
current?current?– No closer than ½ the diameter of each No closer than ½ the diameter of each
electrode electrode – Precision vs. overflowPrecision vs. overflow
Adverse AffectsAdverse Affects
Electrical burn due to fold or poor gel Electrical burn due to fold or poor gel techniquetechnique
Skin irritationSkin irritation
IontophoresisIontophoresis
What is it?What is it?
Introduction of ions into the body Introduction of ions into the body using direct electrical currentusing direct electrical current
Transports ions across a membrane Transports ions across a membrane or into a tissueor into a tissue
Painless, sterile, noninvasive Painless, sterile, noninvasive techniquetechnique
Demonstrated to have a positive Demonstrated to have a positive effect on the healing processeffect on the healing process
Continued . . .Continued . . .
Low-level electrical current carries Low-level electrical current carries drug ions through the skin and into drug ions through the skin and into underlying tissueunderlying tissue
Type of medication used will be Type of medication used will be based on the desired effect to the based on the desired effect to the treated areatreated area– Most common medication is Most common medication is
DexamethasoneDexamethasone
How it WorksHow it Works
Electrical unit uses a direct current Electrical unit uses a direct current that is either a positively or that is either a positively or negatively charged active electrode negatively charged active electrode
An oppositely charged dispersive An oppositely charged dispersive electrode is attachedelectrode is attached
The medication is placed on the The medication is placed on the active electrode so that the active active electrode so that the active electrode has the same charge as electrode has the same charge as the medicationthe medication
Continued . . . Continued . . .
When the electrodes are placed on When the electrodes are placed on the skin and activated, the charge the skin and activated, the charge from the electrode will drive the from the electrode will drive the medication away from the electrode medication away from the electrode and into the area being treatedand into the area being treated
The electrical charge will push the The electrical charge will push the medication through the skin and into medication through the skin and into the tissue to be treatedthe tissue to be treated
IndicationsIndications
InflammationInflammation
EdemaEdema
Bone spurs/calcium depositsBone spurs/calcium deposits
Fungal infectionsFungal infections
ScarsScars
WoundsWounds
Muscle spasmsMuscle spasms
Physiological and Physiological and Therapeutic EffectsTherapeutic Effects
Physiological:Physiological:– Decreased edema Decreased edema
and inflammationand inflammation– Pain controlPain control– Tissue adhesionTissue adhesion– Decreases muscle Decreases muscle
spasmspasm– Wound healingWound healing
Therapeutic:Therapeutic:– Delivers medication Delivers medication
at a constant rate at a constant rate so the effective so the effective plasma plasma concentration concentration remains within the remains within the therapeutic windowtherapeutic window for an extended for an extended period of timeperiod of time
Therapeutic windowTherapeutic window
The range between the minimum The range between the minimum plasma concentration of a drug plasma concentration of a drug necessary for a therapeutic effect necessary for a therapeutic effect and the maximum effective plasma and the maximum effective plasma concentration (above which adverse concentration (above which adverse effects may occur)effects may occur)
Preparing the Patient for ESPreparing the Patient for ES
Sensory testing: Sensory testing: – Which sensation?Which sensation?– Why?Why?
Skin prepSkin prep– Remove oilRemove oil– MoistenMoisten
HairHair– Clip, don’t shaveClip, don’t shave
Iontophoresis GeneratorIontophoresis Generator
Intensity:Intensity: 3-5 mA 3-5 mA Unit adjusts to Unit adjusts to
normal variations normal variations in tissue in tissue impedance impedance Reduces the Reduces the
likelihood of likelihood of burnsburns
Automatic Automatic shutdown shutdown
Iontophoresis GeneratorIontophoresis Generator
Adjustable TimerAdjustable Timer Up to 25 minUp to 25 min
Iontophoresis GeneratorIontophoresis Generator
Lead wiresLead wires Active electrodeActive electrode Inactive electrode Inactive electrode
Current IntensityCurrent Intensity
Low amperage currents are more Low amperage currents are more effective than high currentseffective than high currents– Higher currents tend to reduce effective penetration Higher currents tend to reduce effective penetration
Recommended current: 3-5 mARecommended current: 3-5 mAMaximum current may be determined Maximum current may be determined by the size (surface area) of the by the size (surface area) of the active electrodeactive electrode– Current may be set so that the current Current may be set so that the current
density under the active electrode falls density under the active electrode falls between 0.1 - 0.5 mA/cmbetween 0.1 - 0.5 mA/cm22
Current IntensityCurrent Intensity
Increase current slowly until patient Increase current slowly until patient reports tingling or prickly sensationreports tingling or prickly sensation
If pain or a burning sensation occurs, If pain or a burning sensation occurs, current is too great and should be current is too great and should be decreased decreased
When terminating treatment, current When terminating treatment, current should be slowly decreased to zero should be slowly decreased to zero before electrodes are disconnectedbefore electrodes are disconnected
Treatment TimeTreatment Time
Ranges between 10-20 minRanges between 10-20 min
Check skin every 3-5 minutes for Check skin every 3-5 minutes for signs of irritationsigns of irritation
Decrease current during treatment to Decrease current during treatment to accommodate for decrease accommodate for decrease in skin impedance to avoid pain or in skin impedance to avoid pain or burningburning
Dosage of MedicationDosage of Medication
Dosage is expressed in milliampere-Dosage is expressed in milliampere-minutes (mA-min)minutes (mA-min)
Total drug dose delivered (mA-min) = Total drug dose delivered (mA-min) = currentcurrent X X treatment timetreatment time
Typical iontophoresis drug dose is Typical iontophoresis drug dose is 40 40 mA-minmA-min
Traditional ElectrodesTraditional Electrodes
Older electrodes made of tin, copper, Older electrodes made of tin, copper, lead, aluminum, or platinum backed by lead, aluminum, or platinum backed by rubber rubber
Completely covered by sponge, towel, Completely covered by sponge, towel, or gauze which contacts skin or gauze which contacts skin
Absorbent material is soaked with Absorbent material is soaked with ionized solution (medication)ionized solution (medication)
Commercial ElectrodesCommercial ElectrodesElectrodes have a small chamber Electrodes have a small chamber covered by a semi-permeable covered by a semi-permeable membrane into which ionized solution membrane into which ionized solution may be injected may be injected
The electrode self adheres to the skinThe electrode self adheres to the skin
Electrode PreparationElectrode Preparation
Shave and clean skin Shave and clean skin prior to attaching the prior to attaching the electrodes to ensure electrodes to ensure maximum contact maximum contact
Do not excessively Do not excessively abrade the skin during abrade the skin during cleaningcleaning
Damaged skin has Damaged skin has lower resistance to lower resistance to current current – Increased risk of Increased risk of
burnsburns
Electrode PreparationElectrode Preparation
Attach self-adhering Attach self-adhering active electrode to active electrode to skinskin
Electrode PreparationElectrode Preparation
Inject ionized solution Inject ionized solution into the chamberinto the chamber
Electrode PreparationElectrode Preparation
Attach self-adhering Attach self-adhering inactive electrode to inactive electrode to the skin and attach the skin and attach lead wires from the lead wires from the generatorgenerator
Electrode PlacementElectrode Placement
Size of electrodes can cause variation in Size of electrodes can cause variation in current density current density – Smaller = higher densitySmaller = higher density– Larger = lower densityLarger = lower density
Electrodes should be separated by at Electrodes should be separated by at least the diameter of active electrodeleast the diameter of active electrode Wider separation minimizes superficial Wider separation minimizes superficial
current densitycurrent density Decreased risk for burnsDecreased risk for burns
Electrode PlacementElectrode Placement
Selecting the Appropriate Selecting the Appropriate IonIon
Negative ions (medication) driven into Negative ions (medication) driven into tissues by the negative leadtissues by the negative lead– Accumulation of negative ions in the Accumulation of negative ions in the
tissues tissues
Produces an Produces an acidic reactionacidic reaction through through the formation of hydrochloric acidthe formation of hydrochloric acid Results in hardening of the tissues by Results in hardening of the tissues by
increasing protein densityincreasing protein density
Continued . . .Continued . . .
Positive ions (medication) driven into Positive ions (medication) driven into tissues by the positive leadtissues by the positive lead– Accumulation of positive ions in the tissues Accumulation of positive ions in the tissues
Produces an Produces an alkaline reactionalkaline reaction through the formation of sodium through the formation of sodium hydroxide hydroxide Results in softening of the tissues by Results in softening of the tissues by
decreasing protein densitydecreasing protein density Useful in treating scars or adhesionsUseful in treating scars or adhesions Some positive ions may also produce Some positive ions may also produce
an analgesic effect an analgesic effect
Selecting the Appropriate Selecting the Appropriate IonIon
InflammationInflammation Dexamethasone (-)Dexamethasone (-) Hydrocortisone (-)Hydrocortisone (-) Salicylate (-)Salicylate (-)
SpasmSpasm Calcium (+)Calcium (+) Magnesium (+)Magnesium (+)
AnalgesiaAnalgesia Lidocaine (+)Lidocaine (+) Magnesium (+)Magnesium (+)
EdemaEdema Hyaluronidase(+)Hyaluronidase(+) Salicylate (-)Salicylate (-) Mecholyl (+)Mecholyl (+)
Open Skin LesionsOpen Skin Lesions Zinc (+)Zinc (+)
Scar TissueScar Tissue Chlorine (-)Chlorine (-) Iodine (-)Iodine (-) Salicylate (-)Salicylate (-)
Adverse EffectsAdverse Effects
Chemical burnsChemical burns
Thermal burnsThermal burns
Skin irritationsSkin irritations
Patient PreparationPatient PreparationFor All Types of ESFor All Types of ES
Preparing the PatientPreparing the Patient
Explain Explain what, why, howwhat, why, how– What: What:
full name plus ‘translation’ of what it full name plus ‘translation’ of what it isis
– Why: Why: Pain relief, muscle strengthening, etcPain relief, muscle strengthening, etc
– How:How:Gate control?Gate control?
Opiate release?Opiate release?
Preparing the PatientPreparing the Patient
Sensation testingSensation testing
Test/demonstrate on yourself firstTest/demonstrate on yourself first– Check for Check for
broken leads broken leads
dead batteriesdead batteries
Sensitive dialsSensitive dials
– Gain confidence of patientGain confidence of patient
Preparing the PatientPreparing the Patient
Prepare electrodesPrepare electrodes– Plug the leads in firstPlug the leads in first– Use correct gelUse correct gel
No gel BETWEEN electrodes!No gel BETWEEN electrodes!
– Moisten self-adhesive electrodes or IFC Moisten self-adhesive electrodes or IFC pads WELLpads WELL
Tape or strap electrodes securelyTape or strap electrodes securely
Questions??Questions??
Comprehension CheckComprehension Check
1.1. What are the 4 main purposes of What are the 4 main purposes of applying therapeutic electric currents?applying therapeutic electric currents?
2.2. What pain mechanism is affected by What pain mechanism is affected by the use of TENS?the use of TENS?
3.3. What are the 4 modes of TENS? Which What are the 4 modes of TENS? Which would be used for chronic pain?would be used for chronic pain?
4.4. What are the contraindications for What are the contraindications for TENS?TENS?
5.5. When and why is IFC used over TENS?When and why is IFC used over TENS?
Comprehension CheckComprehension Check
6.6. How should the electrodes be set up to How should the electrodes be set up to achieve a quadipoloar field for IFC?achieve a quadipoloar field for IFC?
7.7. What are the therapeutic uses for What are the therapeutic uses for NMES?NMES?
8.8. What are the indications for What are the indications for iontophoresis?iontophoresis?
9.9. How is the maximum current of How is the maximum current of iontophoresis determined?iontophoresis determined?
10.10.What is the typical dosage of a drug What is the typical dosage of a drug for iontophoresis?for iontophoresis?
AnswersAnswers1.1. The 4 main purposes of applying The 4 main purposes of applying
therapeutic electric currents are:therapeutic electric currents are:– Pain reliefPain relief– Neuromuscular Electrical stimulationNeuromuscular Electrical stimulation– Tissue/wound healingTissue/wound healing– Direct stimulation of denervated muscleDirect stimulation of denervated muscle
2.2. The pain mechanism affected by the The pain mechanism affected by the use of TENS is the gate control theoryuse of TENS is the gate control theory
AnswersAnswers
3.3. The 4 modes of TENS are:The 4 modes of TENS are:– ConventionalConventional– AcupunctureAcupuncture– Burst mode (used for chronic pain)Burst mode (used for chronic pain)– Brief-intense/noxious levelBrief-intense/noxious level
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4.4. The contraindications for TENS are:The contraindications for TENS are:– UNDIAGNOSED PAIN– ANY electronic implant
Some Pacemakers (fixed rate ok but rate responsive are Some Pacemakers (fixed rate ok but rate responsive are affected)affected)
Cardioverter-defribrillatorsCardioverter-defribrillators
– Some Bladder stimulatorsSome Bladder stimulators – Metal implants???
5.5. When and why is IFC used over TENS?When and why is IFC used over TENS?
AnswersAnswers5.5. IFC is used over TENS because:IFC is used over TENS because:
– ““Medium frequency” Medium frequency” less skin less skin impedanceimpedance
– Less impedance Less impedance more patient comfort more patient comfort– More patient comfort More patient comfort tolerate higher tolerate higher
amplitude current amplitude current deeper penetration deeper penetration
6.6. To achieve a quadipolar field for IFC To achieve a quadipolar field for IFC the electrodes from the same circuit the electrodes from the same circuit diagonal to each other forming a box diagonal to each other forming a box around the target sitearound the target site
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7.7. The therapeutic uses for NMES are:The therapeutic uses for NMES are:– Strengthens musclesStrengthens muscles– Motor Re-educationMotor Re-education– Increases ROMIncreases ROM– Enhances enduranceEnhances endurance– Reduces muscle spasm/spacityReduces muscle spasm/spacity
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8.8. The indications for iontophoresis The indications for iontophoresis are:are:– InflammationInflammation– EdemaEdema– Bone spurs/calcium depositsBone spurs/calcium deposits– Fungal infectionsFungal infections– ScarsScars– WoundsWounds– Muscle spasmsMuscle spasms
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9.9. The maximum current of The maximum current of iontophoresis is determined by the iontophoresis is determined by the size (surface area) of the active size (surface area) of the active electrodeelectrode
10.10.The typical dosage of a drug for The typical dosage of a drug for iontophoresis is iontophoresis is 40 40 mA-min