Electro Basics
What is the term that refers to the net charge (negative or positive)?
Polarity
How would you describe the gate keeper and endogenous opiates theory to your patient?
interruption of pain signal, change in perception of pain, release of natural chemicals in the body that make pain feel better.
Why do we need a duty cycle (on/off times) for NMES?
To allow full repolarization during the off time, therefore permitting another full, strong contraction during the on time.
After e-stim, your patient's redness should go away within ____ hours.
3
True or false: myelin sheath serves as a conductor.
False. Myelin sheath is an insulator. The nerve axon serves as a conductor.
True or false: NMES recruits mm fibers in the same pattern as volitional contraction.
False. Alternative pattern of recruitment based on proximity to stimulation.
Your patient reports absent light touch sensation to the left half of their body following a stroke. Can you still use FES?
Yes, impaired sensation is a precaution, not a contraindication.
If your patient is coming to with weakness and pain after surgery, what additional question should you ask the patient (or the surgeon) before provoking a motor response?
Ensure your patient does not have any precautions or restrictions in movement.
When electrical signal is sent into the body, it moves ions, which creates friction/vibration generating heat. This is known as the ___________ physiologic response.
Electrothermal
Which of the following type of e-stim is most likely to utilize a monopolar electrode configuration?
A. NMES
B. LIDC
C. IFC
D. Noxious TENS
B
What are two common uses for muscle EMG within PT?
Muscle EMG can be used to diagnose (often paired with NCVT) or for biofeedback.
Rank the following types of current in order of highest risk of adverse event to lowest risk.
1. Monophasic pulsed current
2. Direct current
3. Alternating or biphasic pulsed current
1. Dc
2. Monophasic PC
3. AC or biphasic PC
Yes. Due to larger size, more superficial location, and increase myelination, sensory nerves are activated first, followed by motor nerves, and pain sensing nerves last.
What are common parameters settings (ranges) for conventional TENS
Frequency:
Pulse duration:
Amplitude: (goal)
Duration:
Freq: high 50-150 pps
PD: Short 50-100 msec
Amp: mild tingling sensation
Duration of painful activity
What types of current can be utilized for wound/tissue healing?
Which physiologic response explains why iontophoresis has the highest safety risk and requires more frequent skin checks?
The electrochemical response
What are the 3 factors that influence the excitatory response of the muscle (assuming the mm is fully innervated)?
You've adjusted NMES parameters. With the same electrode placement and parameters, you notice a decreased, delayed, and inconsistent motor response from the mm. What is likely the cause?
Peripheral nerve injury with some remaining innervation.
You receive an Rx to provide 2% calcium chloride (-) at a dose of 80 mA-min to your patient's right upper trap muscle to help with pain and muscle spasms. Which electrode would act as the active electrode?
At a current of 4.0 mA, how long would it take to deliver the dose?
Cathode and 20 minutes
1. drug allergies
2. skin sensitivity