Electrical Stimulation for Wound Healing Flashcards
What causes arterial ulcers?
Arterial insufficiency due to lack of blood flow secondary to atherosclerosis
What causes venous ulcers?
Venous Insufficiency due to the valves not being patent which causes pressure to persist causing skin breakdown.
What do arterial insufficiency ulcers look like?
They have punched out appearance due to lack of blood supply
What type of electrical stimulation has been proven to accelerate wound healing?
high voltage, monophasic, pulsed
HVPC e-stim is most successful in accelerating the healing of what?
pressure ulcers
What are the 7 ways electrical stimulation promotes healing?
- Restores the current of injury
- Galvanotaxis
- Stimulates cellular activity
- Increases blood flow
- Has bacteriocidal properties
- Decreases edema
- Autolytic debridement
Why does e-stim need to restore current following injury?
Our epidermis loses its electronegative properties when there is a break in the skin. This change in polarity is necessary for healing but is thought to get “stuck” in chronic wounds and e-stim may be required to return it to its original polarity.
What is galvanotaxis?
The stimulation of cells to move along an electrical gradient, therefore promoting cells to the injured area
When e-stim stimulates cells what 2 functions does it increase?
cell proliferation and cellular function
How does e-stim promote an increase in cell proliferation?
An electrical current triggers the calcium channels to open which means intracellular calcium levels increase. This creates additional insulin receptors to be opened. The insulin receptors bind insulin which then signals the fibroblasts to synthesize DNA and collagen.
E-stim increases blood flow by increasing ____ availability
oxygen
Do anodes or cathodes have greater bactericidal properties?
cathode
Theoretically, how does HVPC decrease edema?
By reducing microvascular permeability
E-stim must be used as an adjunct to what?
wound care
What is considered standard wound care?
basically just dressings
What type of wounds can you use e-stim on?
It is appropriate for all stages and types of wounds
Chronic ulcers are defined as ulcers that have not healed within __ days of occurrence
30
E-stim or electromagnetic therapy will be covered only after appropriate standard wound therapy has been tried for at least __ days and there are no measurable signs of improved healing
30
What are the 3 methods of wound e-stim treatment?
- Direct
- Periwound
- Immersion
Voltage must be greater than __ volts to be considered high volt
150
Utilization of a cathode (-) has been proven to do what?
decrease infection
Utilization of an anode (+) has been proven to do what?
promote healing
Why must HVPC be monophasic?
It creates polarity, which is important in wound healing.
What is the significance of pulse interruptions in HVPC?
This interrupted current does not allow the tissue to heat because there is not a continuous flow
What is the range of pulse durations for HVPC?
40-100 μs
What is the frequency range for HVPC when there is no edema present?
60-125 pps
What should the amplitude be for HVPC?
Strong enough to produce a comfortable sensory feeling
Typically how long do HVPC treatments last?
45-60 minutes
How many days per week should HVPC for wound healing be applied?
5-7 days per week
What should polarity be set at if the patient is in the inflammatory phase?
negative
What should polarity be set at if the patient is in the proliferation phase?
positive
_____ polarity HVPC retards the formation of acute edema
Negative
HVPC can reduce edema due to inflammation by roughly __%
50%
What should polarity be set at if there is edema present? Why?
Negative, because the negative charge repels negatively charged serum proteins
Where should the 2 electrodes be placed when edema is present?
The negative polarity electrode should be placed over the area of edema
The dispersive electrode should be placed over some other large flat area
Does the range of pulse durations for HVPC differ when edema is present and when it is not?
No, it is fixed at 40-100 μs
What is the frequency range for HVPC when there is edema present?
100-120 pps
Typically how long do HVPC treatments last when the goal is to reduce edema?
20-30 minutes per session
What are the 2 positives of electrical stimulation for wound healing?
- Faster healing
- Less expensive than other forms of wound healing
What is a negative of electrical stimulation for wound healing?
The patient has to remain sitting for an hour
