Unit 2 Flashcards
T/F: More resistance to current, the less current there will be.
True
Capacitance
Current flowing in an insulated area with high resistance will slow & charge will start to store in that area
Impedance
Resistance to the flow of alternating current
What areas will have increased impedance with ESTIM transmission?
high fat content, skin, hair, fascia, ligament, callus, bone, tendon, scar
Direct Current
continuous unidirectional flow of electrons for at least 1 second; used mainly in Iontophoresis
Alternating Current
uninterrupted bidirectional flow of electrons, must change direction at least one per second
2 types of alternating current
Russian: burst modulated AC
IFC: amplitude modulated AC
Pulsed Current
unidirectional OR bidirectional flow of electrons that periodically ceases for a short time period
Duty cycle
on time / total time (on + off time) x 100
Monophasic waveform
pulse charge & phase charge are the same
3 physiological responses to electrical current
electrochemical
electrothermal
electrophysical
Electrothermal effects
more of a concern with DC; redness occurs under electrodes and should resolve in hours
Cells have a net __ intracellular charge.
negative
What are the 3 levels of response to electrical stimulation?
sensory > motor > noxious
Sensory fibers
A-beta sensory fibers