Currents by Name: Variations of the basic currents

Russian Current

• variation of AC

• activates skeletal muscle

• burst* modulation - defining characteristic

• 2,500 Hz (carrier frequency) alternating sinusoidal current that is interrupted & delivered in short bursts

• 50 bps using 10-msec bursts

• 10/50/10

• actual duty cycle = 16.7%

• relative duty cycle = 50%

  • current is flowing half of the time

Aussie Current/Burst Modulated AC

• created from 1,000 Hz burst modulated AC

• delivered in 4-msec bursts

• greater torque production, efficiency, and decreased rate of muscle fatigue

High Volt Pulsed Current

• twin-peaked monophasic pulsed current waveform

• peak voltage ~150-500 V

• Pulse duration short ~50 to 100 usec

• Frequency of 1-100 Hz*

• low relative duty cycle <1%

• low average treatment voltage

• indications: wound healing*, pain

High Volt vs. Low Volt Pulsed Current

• refers to the magnitude of the voltage used to drive the current

• High volt — voltage: 150-500 V

• Low volt — voltage: <150 V

Low intensity DC/Microcurrent

• microcurrent

• DC or monophasic pulsed current

• pulse duration is .5sec — longer than other pulsed currents

• frequency 1 Hz (up to 1,000 Hz)

• facilitates tissue healing

Microcurrent

any current with an amplitude <1 mA

Symmetrical & Asymmetrical Biphasic Pulsed Currents

• represents a group of waveforms widely used for muscle stimulation and pain modulation

• square, rectangular, triangular

• vary in duration & amplitude

• little data for use of asymmetrical over symmetrical

Electrical Stimulation Indications

• strengthening of skeletal muscle

• re-education of skeletal muscle

• stimulate denervated skeletal muscle

• pain modulation

• preventing & reducing edema

• increasing blood flow

• tissue healing

• delivery of medication

Indications (Scorebuilders)

• Bell’s Palsy

• decreased ROM

• facial neuropathy

• fracture

• Idiopathic scoliosis

• joint effusion

• labor and delivery

• muscle atrophy

• muscle spasm

• muscle weakness

• open wound/ulcer

• pain

• stress incontinence

• should subluxation

Contraindications

Electrodes should NOT be placed over:

• the trunk or heart in patients with pacemakers or defibrillators

• the pelvic, abdominal lumbar, or hip region in pregnant individuals

• carotid bodies (between STM and trachea)

• over urinary bladder stimulators

• areas of known peripheral vascular disease

• the phrenic nerve, eyes or gonads

• areas of active osteomyelitis

• areas of hemorrhage

Anatomical Landmarks

Contraindications (scorebuilders)

• cardiac arrhythmia

• cardiac pacemaker

• malignancy

• osteomyelitis

• over a pregnant uterus

• over carotid sinus

• patient with a bladder stimulator

• phlebitis

• seizure disorder

Precautions

Electrotherapy should be used with caution in patients:

• without intact sensation

• who are unable to communicate

• with compromised mental ability or lack of cognition

• with cardiac dysfunction

• with epilepsy or seizure disorders

• over active or previous neoplasms

• over compromised skin

• over tissues vulnerable to hemorrhage or hematoma

• in the cervical or craniofacial region in patients with hx of CVA or seizures

• Do not use ES device within 5 yards of diathermy units or other sources of electromagnetic radiation

Therapeutic Effects (scorebuilders)

• decreased edema

• decreased pain

• eliminate disuse atrophy

• facilitate bone repair

• facilitate wound healing

• improved ROM

• increased local circulation

• muscle re-education

• muscle strengthening

• relaxation of muscle spasm

Knowledge Check 1: Decreased sensation

Which of the following is not an absolute contraindication to use of electrical stimulation?

A. osteomyelitis

b. over the carotid sinus

c. over the eyes

d. decreased sensation

Dials, Buttons, & Touchscreens

• make sure estim unit has working batteries

• connect electrodes to the lead wires and connect wires to unit

• place electrodes on the skin

• pull the lid cover down to access controls

• to turn on: turn the amplitude knob of at least one channel

• mode: synchronous, constant, alternate

• set: rate, width (Hz) (microseconds), ramp (s), on time (s), off time (s), time (min)

• up/down arrows

• turn the channel knob to adjust intensity

Electrodes

• the device that relays current between the electrical stimulation device and the patient

• two classes of electrodes:

  • surface/transcutaneous

  • invasive/indwelling

• carbonized silicon rubber

• variety of shapes and sizes

• Current density, impedance, current flow

  • small electrodes

  • large electrodes

  • distance apart

Applying electrodes

• evaluate skin surface

• shaving recommended 1 day prior

• consider use of water to improve adhesiveness

• full contact with skin, avoiding bumps in pad or pads touching one another

• if pads won’t stick, do not attach with tape or elastic

• check plastic sheet, usually “ON”

Electrode Placement

• base off what the treatment is trying to accomplish

• ex: motor nerves = motor points (muscle belly or proximal 1/3)

• interelectrode distance - distance between electrodes

  • wider placements = greater depth of penetration/more motor unit or sensory fiber activation

Electrode Size

Small Electrodes:

• increased current density

• increased impedance

• decreased current flow

Large Electrodes:

• decreased current density

• decreased impedance

• increased current flow

Electrode Configuration: Monopolar

active electrode positioned over the treatment area while another electrode is placed over nearby nontreatment area

• active electrode vs. reference/inactive electrode

• cathode is active and produces cell depolarization, produces net charge

Electrode Configuration: Bipolar

all the electrodes are placed over the treatment area

• parallel or perpendicular to the fiber direction of the muscle

• electrodes alternate between + and - with no net charge produced

Electrode Configuration: Quadripolar

four electrodes from two separate circuits, placed so currents are intentionally crossed over target tissues

• requires specific application of channels to achieve effect

Pain Modulation parameters

high frequency, low frequency, brief intense, hyperstimulation

Preventing & Reducing Edema (FYI)

acute (24-72 hours) or existing edema (Subacute or chronic)

Increasing Blood Flow (FYI)

vasospastic disorders and diminished arterial blood flow

Tissue healing (FYI)

• epithelialization, autolysis, reaction of inflammatory process

• promotion of granulation of wound

• bacterial effect for infection

Iontophoresis

• used to induce movement of ions across skin

• delivers medicinal ion

• typically uses DC current

  • risk for burns

• soft tissue inflammatory conditions, neuralgia, edema, ischemic skin ulcers, hyperhidrosis, plantar warts, gouty arthritis, calciific tendonitis, scar tissue, Peyronie’s disease

Iontophoresis Ions

Iontophoresis Dosage

• Dosage (mA min) = Current (mA) x Duration (min)

• Typical: 20-80 mA min

• Amplitude: 0.5-4 mA

  • Ex: 4 mA at 10 minutes = 40 mA min

• INCREASING time can INCREASE absorption

Documentation

• screen for contraindications/precautions

• skin integrity

• modality type

• waveform type

• waveform parameters (pulse duration, frequency, amplitude, on/off time, ramp up/down, burst duration, beat frequency, sweep, scan, swing)

• treatment duration

• electrode size

• electrode placement

• patient position/body position

• response to treatment, including skin integrity

First, DO NO HARM

• effective use of estim is founded on two factors:

  • careful differentiation of patients who stand to benefit from the intervention from those who are not appropriate

  • careful, knowledgable, and safe application of the intervention

• There are risk associated with most all treatment interventions

• proper screening is critical

• be aware of surroundings — inspect equipment and report problems

Key safety information

• proper screening must be performed PRIOR TO use of estim

  • contraindications (required)

  • sensation is a precaution only — check if concerned

  • capillary refill/blanche is not required

Must inc. intensity SLOWLY

• must provide patient with off switch/bell

• must dec. intensity prior to shutting off

• must inspect skin FOLLOWING application

Clinical Decision Making