Electrical stimulation for Tissue Repair

3 currents

1.) low-intensity direct current (LIDC) → used for iontophoresis

2.) Microcurrent (MC) → used for healing cutaneous wounds

3.) high-voltage pulsed current (HVPC) → used for healing wounds, injuries, and to decrease swelling

High voltage pulsed current (AKA high volt stimulation)

1.) high volt indicates voltage > 150 (up to 500)

2.) must have twin peak monophasic (DC) current

High volt stimulation benefits

1.) high voltage allows deeper penetration

2.) twin peaks does not allow small sensory fibers (A-delta and C) to be stimulated (increased comfort)

3.) average current remains low due to short phase duration resulting in a safe current

4.) duration of both peaks usually is between 100 and 200ms → phase duration can not be adjusted by the clinician

Microcurrent therapy → Microcurrent electrical stimulation

1.) stimulus amplitude is in the micro amperage range

2.) monophasic, continuous or pulsed current, with polarity reversal

3.) peak amplitude is below Rheobase of A-beta afferent fibers → no depolarization takes place (sub-sensory, sub-motor)

Skin battery

1.) normal skin has a flow of electrical current

2.) electrical currents flow between the injured skin and the healthy skin

3.) application of electrical current mimics and amplifies those endogenous currents

Galvanotaxis

polarized cells are attracted to the opposite polarity, enhancing healing

Inflammatory phase

1.) positive polarity

-attracts neutrophils and macrophages

Proliferation phase

1.) negative polarity

-attracts fibroblasts and promotes collagen formation

Remodeling/maturation phase

1.) negative polarity

-attracts keratinocytes and epidermal cells

Germicidal effect

not much research → 250v, 2 hours

Edema reduction with HiVolt

1.) HiVolt only (not microcurrent or low volt DC)

2.) negative polarity → repels negatively charged proteins

3.) monophasic electrode placement → treatment electrode over the area of swelling, dispersal electrode proximal

4.) can be done in conjunction with PRICE

Other indications for HiVolt

1.) muscle spasm reduction → similar to Russian current, Russian preferred due to lack of polarity effect

2.) pain reduction → some evidence but NOT recommended, interferential and TENS preferred due to lack of polarity effect

High Volt stimulation

1.) frequency of most high voltage units charges from 1-120pps

-theoretically allows for the incorporation of either acute pain (80-150) or chronic pain (0-15) settings or muscle contraction for spasm relief (30-50

Monopolar electroe placement

1.) active electrode over the area of complaint → sterile gauze and foil in wound, active electrode over area of swelling

2.) dispersal pad proximal to the site → allows for deeper penetration

3.) set polarity based on stage of healing

Indications

1.) Hivolt and microcurrent → stimulate healing → wound healing, germicidal

2.) hivolt only → decrease edema, decrease spasm/guarding, pelvic floor

Risks

1.) if treating infected wounds careful disinfection of electrodes is needed

2.) don’t use cold coupling media for treating chronic wounds → slows down cellular activity

PH changes with monophasic current

1.) positive polarity attracts acids → positive repels bases

2.) negative polarity attracts bases → negative repels acids