Week 7 Flashcards
List the following for high-rate TENS
-Waveform
-Pulse Duration
-Frequency
-Amplitude
-Duration
-Waveform: monophasic pulsed (hi-volt) or biphasic pulsed
-Pulse Duration: < or equal to 100usec
-Frequency: 100-150 pps
-Amplitude: sensory level
-Duration: 30 min or less in clinic; 1 hour at home with 30 min off
List the following for low-rate TENS
-Waveform
-Pulse Duration
-Frequency
-Amplitude
-Duration
-Waveform: monophasic pulsed (hi-volt) or biphasic pulsed
-Pulse Duration: 150-200usec
-Frequency: < or equal to 10pps
-Amplitude: motor level; visible contraction
-Duration: 30 min or less
List the following for IFC
-Waveform
-Pulse Duration
-Frequency
-Amplitude
-Duration
-Waveform: amplitude modulated AC
-Pulse Duration: 2kHz = 250usec; 4kHz = 125usec
-Frequency: 2kHz = muscle contraction; 4kHz = reduced pain
-Amplitude: will rise and fall at frequency equal to beat frequency; 50Hz for muscle contraction; 100 Hz for high rate pain modulation; 1-10Hz for low rate pain modulation
-Duration: 10-20 min most common (up to 30)
List the following for ES for acute tissue healing
-Waveform
-Pulse Duration
-Frequency
-Amplitude
-Duration
-Waveform: HVPC negative polarity
-Pulse Duration: 40-100us
-Frequency: 60-125 pps
-Amplitude: to produce comfortable tingling
-Duration: 45-60 min
List the following for ES for chronic tissue healing
-Waveform
-Pulse Duration
-Frequency
-Amplitude
-Duration
-Waveform: HVPC positive polarity
-Pulse Duration: 40-100us
-Frequency: 60-125 pps
-Amplitude: to produce comfortable tingling
-Duration: 45-60 min
what are the contraindications/precautions for TENS and ES
-Over pregnant uterus, abdomen or lower back in pregnancy (may be used for pain control during labor and delivery)
-Electrical implants
-Carotid sinus, eyes, internally or on reproductive organs
-Over damaged skin
-Thrombosis
-Thrombophlebitis
-Hemorrhage
-Over malignant tumors
-Undiagnosed pain
-Patients with impaired sensation or cognitive ability, and others
-Do not use stimulated muscle contractions for pain control, as with low-rate TENS, when muscle contractions may disrupt healing (ex. Muscle or tendon tear, overuse, or acute injury)
what are the two types of second order neurons?
-high threshold neurons: nociceptive-specific receiving input from peripheral nociceptors only
-wide-dynamic range neurons: receive input from nociceptive and non-nociceptive primary afferent fibers
what does central sensitization result in?
-increased responsiveness to noxious and non-noxious stimuli
-increase receptive field
-decreased activation thresholds
why is treating pain of an unknown or unidentifiable origin considered a contraindication of TENS?
masking undiagnosed pain with TENS can postpone proper treatment and lead to worsening of underlying condition
what is the gate control theory?
-selective stimulation of large-diameter A-beta sensory nerve fibers block noxious afferent input from smaller-diameter unmyelinated nociceptive C fibers and small myelinated A-delta fibers
what are the main mechanisms of action for TENS
-activation of peripheral opioid receptors
-activation of central opioid receptors
what is burst mode tens?
-uses same mechanism as low-rate TEN but may produce a more comfortable muscle contraction
-combination of high rate and low rate TENS stimulation delivered in bursts (high freq. pulses (100hz) delivered at low freq. (1-4hz) and long duration (150-200usec) at motor level
what are the two main theories for TENS?
-gate control theory: Activation of A-beta afferents to induce inhibitory circuits in dorsal horn to block A-delta and C-fiber input
-central inhibition and release of endogenous opioids: Activation of descending inhibitory pathways projecting to spinal cord; Selective activation of opioid receptors: Low-frequency TENS: µ-opioid receptors; High-frequency TENS: δ-opioid receptors
what is the correct placement for TENS?
-around or over painful area
-lead wire color is irrelevant
-over the peripheral nerve that innervates the painful area
-parallel to spine to stimulate nerve roots of spinal nerves innervating painful area
-over acupuncture points, motor points, or trigger points
what is IFC?
-consists of two interfering medium-frequency alternating currents intersecting to yield a single treatment
-reduces skin impedance and reaches deeper tissues with less discomfort
-requires 2 channels/4 electrodes set up is x pattern
what is constructive interference?
amplitudes of the 2 currents are in sync and will sum together
what is destructive interference?
amplitudes of the 2 currents are out of sync and will cancel each other out
what is amplitude modulation?
amplitude of the current increases and decreased as the 2 waves are in and out of sync creating
what is sweep (in reference to IFC)?
-modulation of the beat frequency
-to allow low and high freq. stimulation within the same treatment
what is swing (in reference to IFC)?
-characteristic of sweep
-can set the beat freq. to just go from min to max or move continuously through the range of min to max
what is vector scan in relation to IFC?
-amplitude modulation of the input currents
-increases the area of the interference pattern
-provides simulation to a larger tissue area
what is premodulated IFC current?
-bipolar IFC
-applied using 2 electrodes
-current is created by the interference of two alternating currents within the stimulator device, not by interference within the pt’s tissues
what is the sequence for the application of TENS?
-position patient and drape as needed
-clean skin
-connect wires to electrodes
-place electrodes
-set parameters
-slowly increase amplitude until mild tingling, continue to increase to strong, comfortable sensation and muscle twitch
-when treatment time completes, reduce the amplitude back to the minimum and turn off machine
-remove electrodes and inspect the skin
what are the contraindications and precautions for TENS?
- Over pregnant uterus, abdomen or lower back in pregnancy (May be used for pain control during labor and delivery)
- Electrical implants
- Carotid sinus, eyes, internally or on reproductive organs
- Over damaged skin
- Thrombosis
- Thrombophlebitis
- Hemorrhage
- Over malignant tumors
- Undiagnosed pain
- Patients with impaired sensation or cognitive ability, and others
- Do not use stimulated muscle contractions for pain control, as with low-rate TENS, when
muscle contractions may disrupt healing (e.g. muscle or tendon tear, overuse, or acute
injury).
