BPA FINAL EXAM QUESTIONS AND ANSWERS
What is a cathode? - Answers - - Negative electrode
- Attracts positive cations
What is an anode? - Answers - - positive electrode
- Attracts negative anions
What are the contraindications to surface electrical stimulation? - Answers - - cardiac
pacemaker/implanted devices
- Unstable cardiac arrythmia to chest area
- Over the carotid sinus
- Over the abdomen/low back
- Over acute venous arterial thrombii
What are the precautions for surface electrical stimulation? - Answers - - Cardiac
disease
- Wounds and skin irritation
- Impaired mentation/sensation
- Malignancy
What is bipolar electrode placement? - Answers - - Two points of electrodes of equal
size to bracket the point of pain
- Most commonly used
What is monopolar electrode placement? - Answers - - Smaller electrode will have more
current density
- Pt will feel more because the current is more dense in a smaller area
- Used with point stimulation, iontophoresis, acupuncture points
What are the 3 excitable responses to electrical stimulation? - Answers - - A beta;
sensory
- A alpha; motor
- A delta; sharp pain, fast
Explain how stimulus duration choices can be picked for a specific excitable response
such as A beta nerve firing - Answers - - Short durations are used to fire a beta
- Longer durations are used to recruit a alpha and a delta
- Most machines do not have long enough duration to reach C fibers or denervated
muscles
What are the parameters for conventional sensory stimulation? - Answers - Freq- 50 to
150 hz
, Stim. Duration- 20 to 200usec
Intensity- mild to moderate tingling
Duration- 15 to 30 mins
How does sensory or conventional estim bock the gate to pain? - Answers - - Sensory
receptor bombardment
- Electrodes on skin use a strength duration combination to fire a beta nerves closer to
the electrodes
- To block the gate, info goes to the spinal cord, a switch usually flips to tell the brain
about the pain, but instead, A beta fibers make the switch go the other way and block
the gate to block pain
What is adaptation? - Answers - - When a nerve is presented with a stimulus for an
extended period of time and raises its threshod so less AP are created.
- A frequency sweep is the most common modulation (80-150 or 50-150)
What are the three different current types in order of highest to lowest frequency? -
Answers - DC, AC, PC
What is direct current? - Answers - - unit of directional flow of current for at least 1
second without gaps in that flow
- Cannot be denoted by frequency because it is either off or no
What is alternating current? - Answers - - Continous bi directional flow of ions,
electrons, etc.
- Sinosoidal wave
- No gaps in current
- No charge build up because it is constantly changing
- Number of times wave repeats itself is frequency
- Various cycles per second
What is pulsed current? - Answers - - Can be directional or unidirectional
- allows for flexibility in treatment because it has little gaps
What different waveforms can be used to deliver surface estim to block acute pain? -
Answers - - AC waveforms; IFC and pre mod IFC
- PC waveforms; HVPC, BPC
What is IFC? - Answers - - AC waveform
- Criss cross quadripolar placement
- 2 channels that intersect and create a clover leaf
- Peaks and valleys at the same and alternating points causing summation or
cancelation of the waveform
- Known as amplitude/beat modulated stim
- Good for treating global area like post op
What is a cathode? - Answers - - Negative electrode
- Attracts positive cations
What is an anode? - Answers - - positive electrode
- Attracts negative anions
What are the contraindications to surface electrical stimulation? - Answers - - cardiac
pacemaker/implanted devices
- Unstable cardiac arrythmia to chest area
- Over the carotid sinus
- Over the abdomen/low back
- Over acute venous arterial thrombii
What are the precautions for surface electrical stimulation? - Answers - - Cardiac
disease
- Wounds and skin irritation
- Impaired mentation/sensation
- Malignancy
What is bipolar electrode placement? - Answers - - Two points of electrodes of equal
size to bracket the point of pain
- Most commonly used
What is monopolar electrode placement? - Answers - - Smaller electrode will have more
current density
- Pt will feel more because the current is more dense in a smaller area
- Used with point stimulation, iontophoresis, acupuncture points
What are the 3 excitable responses to electrical stimulation? - Answers - - A beta;
sensory
- A alpha; motor
- A delta; sharp pain, fast
Explain how stimulus duration choices can be picked for a specific excitable response
such as A beta nerve firing - Answers - - Short durations are used to fire a beta
- Longer durations are used to recruit a alpha and a delta
- Most machines do not have long enough duration to reach C fibers or denervated
muscles
What are the parameters for conventional sensory stimulation? - Answers - Freq- 50 to
150 hz
, Stim. Duration- 20 to 200usec
Intensity- mild to moderate tingling
Duration- 15 to 30 mins
How does sensory or conventional estim bock the gate to pain? - Answers - - Sensory
receptor bombardment
- Electrodes on skin use a strength duration combination to fire a beta nerves closer to
the electrodes
- To block the gate, info goes to the spinal cord, a switch usually flips to tell the brain
about the pain, but instead, A beta fibers make the switch go the other way and block
the gate to block pain
What is adaptation? - Answers - - When a nerve is presented with a stimulus for an
extended period of time and raises its threshod so less AP are created.
- A frequency sweep is the most common modulation (80-150 or 50-150)
What are the three different current types in order of highest to lowest frequency? -
Answers - DC, AC, PC
What is direct current? - Answers - - unit of directional flow of current for at least 1
second without gaps in that flow
- Cannot be denoted by frequency because it is either off or no
What is alternating current? - Answers - - Continous bi directional flow of ions,
electrons, etc.
- Sinosoidal wave
- No gaps in current
- No charge build up because it is constantly changing
- Number of times wave repeats itself is frequency
- Various cycles per second
What is pulsed current? - Answers - - Can be directional or unidirectional
- allows for flexibility in treatment because it has little gaps
What different waveforms can be used to deliver surface estim to block acute pain? -
Answers - - AC waveforms; IFC and pre mod IFC
- PC waveforms; HVPC, BPC
What is IFC? - Answers - - AC waveform
- Criss cross quadripolar placement
- 2 channels that intersect and create a clover leaf
- Peaks and valleys at the same and alternating points causing summation or
cancelation of the waveform
- Known as amplitude/beat modulated stim
- Good for treating global area like post op
