Hvps & Interferential Stimulation


Published on

Published in: Health & Medicine, Business
  • Be the first to comment

No Downloads
Total views
On SlideShare
From Embeds
Number of Embeds
Embeds 0
No embeds

No notes for slide
  • Hvps & Interferential Stimulation

    1. 1. HVPS & Interferential Stimulation Adapted from Therapeutic Modalities: Art & Science , Knight & Draper (2008) for KIN 195
    2. 2. Competencies for Therapeutic Modalities TM-C2 Explain the principles of physics, including basic concepts associated with the electromagnetic and acoustic spectra (e.g., frequency, wavelength) associated with therapeutic modalities. TM-C3 Explain the terminology, principles, basic concepts, and properties of electric currents as they relate to therapeutic modalities. TM-C4 Describe contemporary pain-control theories.
    3. 3. Competencies for Therapeutic Modalities, cont. TM-C6 Explain the body's physiological responses during and following the application of therapeutic modalities. TM-C7 Describe the electrophysics, physical properties, biophysics, patient preparation and modality set-up (parameters), indications, contraindications, and specific physiological effects associated with commonly used therapeutic modalities. TM-C8 Identify appropriate therapeutic modalities for the treatment and rehabilitation of injuries and illness.
    4. 4. Law of DuBois Reymond: <ul><li>The amplitude of the individual stimulus must be high enough so that depolarization of the membrane will occur. </li></ul><ul><li>The rate of change of voltage must be sufficiently rapid so that accommodation does not occur </li></ul><ul><li>The duration of the individual stimulus must be long enough so that the time course of the latent period (capacitance), action potential, and recovery can take place </li></ul>
    5. 5. For all modalities… <ul><li>Know the effects, indications, contraindications, & precautions </li></ul><ul><li>Verify the modality is set up correctly before treatment begins </li></ul><ul><li>Prepare the patient psychologically & physically for the treatment </li></ul><ul><li>Begin treatment conservatively and ask for patient feedback </li></ul><ul><li>At the end of treatment, clean up the modality and instruct the patient about next treatment and activity level until then </li></ul><ul><li>Maintain the machines appropriately </li></ul>
    6. 6. Review: Requirements for Ion Migration: Chemical Effects <ul><li>Must have continuous monophasic DC electron flow to cause ion migration. </li></ul><ul><li>Moving electrons against gradient </li></ul><ul><ul><li>Like pushing a car uphill </li></ul></ul><ul><ul><li>When you pause, it rolls back down. </li></ul></ul><ul><li>Why does a twin-pulse high-volt current not produce a chemical effect? </li></ul>
    7. 7. Review: Pulse and Cycle Characteristics (cont.) <ul><li>Pulse named by number of phases </li></ul><ul><ul><li>Monophasic </li></ul></ul><ul><ul><ul><li>One phase </li></ul></ul></ul><ul><ul><ul><li>Current flows in one direction only. </li></ul></ul></ul><ul><ul><li>Biphasic </li></ul></ul><ul><ul><ul><li>Two phases </li></ul></ul></ul><ul><ul><ul><li>Current flows in both directions. </li></ul></ul></ul><ul><ul><li>Polyphasic </li></ul></ul><ul><ul><ul><li>Many phases </li></ul></ul></ul>
    8. 8. Review: Current Timing & Modulation <ul><li>Pulse width (pulse duration) </li></ul><ul><ul><li>Time required for each pulse to complete its cycle </li></ul></ul><ul><ul><li>Reported in microseconds or milliseconds </li></ul></ul><ul><li>Short pulse duration: <150 µ sec </li></ul><ul><li>Long pulse duration: >200 µ sec </li></ul><ul><li>Interpulse interval </li></ul><ul><ul><li>Time between successive pulses </li></ul></ul>
    9. 9. Commonly Used Wave Forms (p. 142, cont.) <ul><li>Twin pulse wave form </li></ul><ul><ul><li>Monophasic, pulsed, twin spiked </li></ul></ul><ul><ul><li>Common wave form of high-volt muscle simulators </li></ul></ul><ul><ul><li>Has been called high-volt galvanic and pulsed direct current </li></ul></ul><ul><ul><li>However, not direct or galvanic current </li></ul></ul><ul><ul><li>Result of misunderstanding physiology </li></ul></ul>
    10. 10. High Voltage Pulsed Current Stimulation for Wound Healing <ul><li>Electrical stimulation for the purpose of repairing tissues includes management of open wounds and edema reduction. </li></ul><ul><li>Production of a twin-peak, monophasic, pulsed current driven by its characteristically high electromotive force or voltage </li></ul><ul><li>Positive or negative polarity </li></ul>
    11. 11. HVPC Common Treatments <ul><li>Versatile and can perform several functions: </li></ul><ul><ul><li>Wound healing (only proven electrical modality proven to promote wound healing) </li></ul></ul><ul><ul><li>Pain modulation (acute & chronic) </li></ul></ul><ul><ul><li>Muscle reeducation and spasm reduction </li></ul></ul><ul><ul><li>Edema reduction (maybe) </li></ul></ul>
    12. 12. Characteristics of High-Volt Stimulator <ul><li>Low volt stimulators generate <150 V </li></ul><ul><li>High volt stimulators generate >150 V </li></ul><ul><li>HVPC uses between 150 and 500 V. </li></ul><ul><li>Low average current </li></ul><ul><li>Twin peak monophasic waveform </li></ul><ul><ul><li>Resembles a double spike with a fast rise followed by a fast decline </li></ul></ul><ul><li>Short pulse widths (100 – 200 µ sec) </li></ul><ul><li>Pulse rates of 1 – 200 Hz </li></ul><ul><li>Generally HVPS uses lower current </li></ul>
    13. 13. Review <ul><li>What is HVPS stand for? Why isn’t it HVGS, according to Knight & Draper? </li></ul><ul><li>Describe the HVPS waveform. </li></ul><ul><li>Name the 4 common uses for HVPS. </li></ul><ul><li>Does HVPS utilize high voltage or high current to achieve outcomes? </li></ul><ul><li>What is the voltage cutoff between high and low voltage stimulators? </li></ul>
    14. 14. HVPC: Uses & Techniques <ul><li>Monophasic current used for </li></ul><ul><ul><li>Wound management </li></ul></ul><ul><ul><li>Acute pain reduction </li></ul></ul><ul><ul><li>Reduction of edema </li></ul></ul><ul><li>Bipolar Technique </li></ul><ul><ul><li>Bipolar used for muscle contraction or chronic pain (Note: HVPS is not as effective as NMES for muscle contraction b/c of lower current in HVPS) </li></ul></ul>
    15. 15. HVPC: Advantages <ul><li>1. Less resistance to the current by the skin </li></ul><ul><li>2. Short phase duration allows for moderately high-intensity muscle contraction with little discomfort </li></ul><ul><ul><li>Other types of stimulators provide a stronger contraction </li></ul></ul><ul><li>3. Highly variable in its functions </li></ul><ul><li>4. Can be used for </li></ul><ul><ul><li>Wound healing </li></ul></ul><ul><ul><li>Pain modulation </li></ul></ul><ul><ul><ul><li>a. Sensory level (acute pain) </li></ul></ul></ul><ul><ul><ul><li>b. Motor level (chronic pain) </li></ul></ul></ul><ul><ul><li>Treating muscle weakness </li></ul></ul><ul><ul><li>Edema reduction </li></ul></ul>
    16. 16. HPVC: Disadvantages <ul><li>Disadvantages </li></ul><ul><ul><li>Cannot provide as strong of a contraction as NMES </li></ul></ul><ul><ul><li>Many aren’t portable. </li></ul></ul><ul><ul><li>Sometimes trial and error are needed to determine electrode polarity for wound healing. </li></ul></ul><ul><ul><li>Effects (muscle contraction) are not as strong as low-volt units. </li></ul></ul>
    17. 17. HPVC: Indications & Contraindications <ul><li>Indications </li></ul><ul><ul><li>Wound lesions (pressure sores, scarring from incisions) </li></ul></ul><ul><ul><li>Edema control and reduction </li></ul></ul><ul><ul><li>Residual or chronic muscle spasm (when low-volt unit unavailable) </li></ul></ul><ul><ul><li>Pain </li></ul></ul><ul><li>Contraindications </li></ul><ul><ul><li>Do not use on patient with pacemaker </li></ul></ul><ul><ul><li>Do not use over </li></ul></ul><ul><ul><ul><li>Heart or brain </li></ul></ul></ul><ul><ul><ul><li>Lumbar and abdominal area of pregnant women </li></ul></ul></ul><ul><ul><ul><li>Potential malignancies </li></ul></ul></ul><ul><ul><ul><li>Anterior cervical area </li></ul></ul></ul>
    18. 18. HPVC Precautions <ul><li>Precautions </li></ul><ul><ul><li>1. Be cautious when using HVPC over an area with: </li></ul></ul><ul><ul><ul><li>a. Impaired sensation </li></ul></ul></ul><ul><ul><ul><li>b. Extensive torn tissue (no use of bipolar) </li></ul></ul></ul><ul><ul><ul><li>c. Hemorrhagic area </li></ul></ul></ul><ul><ul><li>2. Patients with epilepsy should be monitored during treatment. </li></ul></ul>
    19. 19. Review <ul><li>What are the monopolar and bipolar uses of HVPS? </li></ul><ul><li>Name the 4 advantages of HVPS? </li></ul><ul><li>Name the 4 disadvantages of HVPS? </li></ul><ul><li>What are the 4 indications for HVPS? </li></ul><ul><li>What are the 5 contraindications for HVPS? </li></ul><ul><li>What are the 4 precautions for HVPS? </li></ul>
    20. 20. HVPC: Wound Management <ul><li>How does HVPC stimulate wound repair? </li></ul><ul><ul><li>Body possesses bioelectric currents in the vascular and interstitial tissues. </li></ul></ul><ul><ul><li>Blood vessel walls, insulating tissue matrix, interstitial fluid, and intravascular plasma are capable of conducting bioelectricity. </li></ul></ul><ul><ul><li>When tissues are damaged, an electrical potential is created between injured and noninjured tissues. </li></ul></ul>
    21. 21. HVPC: Wound Management (cont.) <ul><li>Polarity may stimulate cellular activity when injured. </li></ul><ul><li>Stimulating d é bridement of injured tissues </li></ul><ul><li>Tissue regeneration and remodeling </li></ul><ul><li>May speed up healing by promoting the natural healing process </li></ul><ul><li>May develop a difference in potential between wound area and the surrounding healthy tissue </li></ul><ul><li>Injury potential typically becomes positive 24 – 48 hr after injury & negative 8 – 9 days after injury. </li></ul><ul><li>As the wound heals, the difference slowly returns to baseline. </li></ul><ul><ul><li>Can be used to enhance the natural process of tissue recovery and healing </li></ul></ul>
    22. 22. HVPC: Edema Management <ul><li>Curbing edema formation </li></ul><ul><ul><li>HVPC does not use DC </li></ul></ul><ul><ul><li>Decreases the permeability of microvessels </li></ul></ul><ul><ul><li>Decreases the leaking of vessels, reducing the number of plasma proteins and amount of fluid that leave the vessels to enter the interstitial spaces </li></ul></ul>
    23. 23. HVPC: Edema Management (cont.) <ul><li>Two protocols for curbing edema </li></ul><ul><li>Water immersion </li></ul><ul><ul><ul><li>-Negative polarity </li></ul></ul></ul><ul><ul><ul><li>-120 pps </li></ul></ul></ul><ul><ul><ul><li>-90% of visible motor threshold </li></ul></ul></ul><ul><ul><ul><li>-30 min treatments every 4 hr </li></ul></ul></ul><ul><ul><ul><li>-Apply ASAP postinjury or as long as edema is still forming </li></ul></ul></ul><ul><li>Resolution of edema once formed </li></ul><ul><ul><li>-Can be employed in a muscle pumping action to get rid of edema </li></ul></ul><ul><ul><li>-Intensity increased until strong muscle contraction </li></ul></ul><ul><ul><li>-Setting of 1 – 10 pps for muscle contraction </li></ul></ul>
    24. 24. HVPC: Pain Modulation <ul><li>Ineffective in reducing the pain of delayed-onset muscle soreness </li></ul><ul><li>Yet has been shown to help relieve pain caused by muscle spasm </li></ul>
    25. 25. HVPC: Electrode Polarity <ul><li>Negative polarity </li></ul><ul><ul><li>Increases </li></ul></ul><ul><ul><ul><li>Vascularity </li></ul></ul></ul><ul><ul><ul><li>Stimulation of fibroblastic growth </li></ul></ul></ul><ul><ul><ul><li>Collagen production </li></ul></ul></ul><ul><ul><ul><li>Epidermal cell migration </li></ul></ul></ul><ul><ul><li>Inhibits bacterial growth </li></ul></ul><ul><li>Positive polarity </li></ul><ul><ul><li>Increases macrophages </li></ul></ul><ul><ul><li>Promotes epithelial growth </li></ul></ul>
    26. 26. HVPC: Electrode Polarity (cont.) <ul><li>Most treatments begin with the negative polarity </li></ul><ul><ul><li>Encourages blood clots to dissolve and increases the inflammatory by products </li></ul></ul><ul><ul><ul><li>Necrotic tissues </li></ul></ul></ul><ul><li>Positive polarity encourages clot formation around the wound and granulation tissue. </li></ul>
    27. 27. REVIEW: Phases of the Inflammatory Process <ul><li>Phase I: Acute Phase ( 2 subphases) </li></ul><ul><ul><li>Early (Acute): inflammatory response: lasts 2-4 days </li></ul></ul><ul><ul><li>Late (Sub-Acute): continue inflammatory phase which is usually complete in 2 weeks </li></ul></ul><ul><li>Phase 2: Tissue Formation (Proliferation) </li></ul><ul><ul><li>Tissue rebuilding approximately 2-3 weeks </li></ul></ul><ul><ul><li>This does not include chronic inflammation </li></ul></ul><ul><li>Phase 3: Remodeling Phase </li></ul><ul><ul><li>Adapt to original tissue </li></ul></ul><ul><ul><li>Continues for up to 1 year post injury </li></ul></ul>
    28. 28. REVIEW: Phase II, Stages of Regeneration <ul><li>Stage starts with periphery/outside </li></ul><ul><li>Re-eptheliaization is proliferation of peripheral epithelial tissue which then migrates to the wound until the area is covered. </li></ul><ul><li>Capillarization (Capillary buds proliferate and connect forming new capillaries which gives the red, granular appearance to the scar (granular tissue) </li></ul>
    29. 29. REVIEW: Chronic Inflammation <ul><li>Complications </li></ul><ul><ul><li>Granuloma: large mass of weaker scar tissue (usually due to large inflammation and activity without regard to healing time) </li></ul></ul><ul><ul><li>Retardation of muscle fiber: with excessive granuloma fibroblasts cannot reach damaged tissue </li></ul></ul><ul><ul><li>Adhesions/contractures in tissue </li></ul></ul><ul><ul><li>Keloid/hypotrophic scars </li></ul></ul>
    30. 30. Application Parameters: HVPC <ul><li>Frequency of application </li></ul><ul><li> As often as three per day if separated by 3–4 hr </li></ul><ul><li>When using the monopolar function, active electrode over the injury and dispersive over a large & remote site </li></ul><ul><li>When using the bipolar function, place electrodes proximal & distal to the muscle belly </li></ul><ul><li>Length of application </li></ul><ul><li>15 min if pulsed or patient is going to exercise post treatment </li></ul><ul><li>15 to 30 min if surge mode is used or patient is not going to exercise post treatment (longer tires out the muscle) </li></ul>
    31. 31. Review <ul><li>How does HVPS stimulate wound repair (10 ways)? </li></ul><ul><li>What are the 2 ways HVPS manage edema? What are the 2 protocols? </li></ul><ul><li>What are the 5 things negative polarity in HVPS effects? What are the 2 things positive polarity in HVPS effects? </li></ul><ul><li>What are the common pad placements, duration and frequencies of treatment w.r.t. HVPS? </li></ul>
    32. 32. Interferential Current <ul><li>Interference or superimposition of two separate medium-frequency sinusoidal currents on one another </li></ul><ul><li>Symmetrical, sinusoidal, medium frequency (2000 – 5000 Hz) AC </li></ul><ul><li>Invented in 1950; used in United States by 1980s </li></ul><ul><li>Fifth most frequently used physical agent </li></ul>
    33. 33. Most Commonly Used Wave Forms <ul><ul><li>DC: DC </li></ul></ul><ul><ul><li>IF: Polyphasic </li></ul></ul><ul><ul><li>HV: Twin pulse </li></ul></ul><ul><ul><li>LV : Biphasic and polyphasic burst (Russian) </li></ul></ul><ul><ul><li>TENS: Biphasic </li></ul></ul>
    34. 34. Commonly Used Wave Forms (p. 142, cont.) <ul><li>Interferential wave form </li></ul><ul><ul><li>Symmetrical, sinusoidal, high frequency (2000 – 5000 Hz) AC </li></ul></ul><ul><ul><li>Two channels, with different frequencies, used simultaneously </li></ul></ul><ul><ul><li>Two currents cause a tissue current amplitude modulation </li></ul></ul>
    35. 35. Commonly Used Wave Forms (p. 142, cont.) <ul><li>Interferential wave form: current amplitude modulation </li></ul>Two identical currents Two opposite currents Two offset currents Usually accomplished with two different frequency currents
    36. 36. <ul><li>Basic principle </li></ul><ul><ul><li>Decrease tissue impedance (resistance) so simulation is less painful </li></ul></ul><ul><ul><ul><li>Impedance at 50Hz = ~3200 Ω </li></ul></ul></ul><ul><ul><ul><li>Impedance at 4000 Hz = ~40 Ω </li></ul></ul></ul><ul><ul><ul><li>Current passes more easily through skin </li></ul></ul></ul><ul><li>Advantages of vector pattern </li></ul><ul><ul><li>Surface and deep stimulation </li></ul></ul><ul><ul><li>Targeted tissues for added benefit </li></ul></ul><ul><ul><li>Treatment of easily localized pain </li></ul></ul><ul><ul><li>Treatment of large areas </li></ul></ul><ul><ul><li>Treatment of poorly defined pain </li></ul></ul>What Is IFC Therapy?
    37. 37. How Does IFC work? <ul><li>Example: One channel runs at 5000 Hz another at 5100 Hz </li></ul><ul><ul><li>Use a dynamic vector (or scan for poorly defined pain) </li></ul></ul><ul><ul><li>Use target for easily localized pain </li></ul></ul><ul><ul><li>Treats most of the area bracketed by the electrodes (scan or dynamic vector) </li></ul></ul>
    38. 38. Is IFC Therapy Effective? <ul><li>Those who have had success </li></ul><ul><ul><li>Correctly position vector </li></ul></ul><ul><ul><li>Use appropriate size and positioning of electrodes </li></ul></ul><ul><ul><li>Use appropriate stimulation parameters </li></ul></ul><ul><ul><li>Persevere, if pain relief is not immediately obtained </li></ul></ul>
    39. 39. Review <ul><li>What is the basic principle of IFC? </li></ul><ul><li>What’s the advantage of the vector pattern? </li></ul><ul><li>What is the waveform of IFC? </li></ul><ul><li>Why does IFC use 2 currents? </li></ul><ul><li>What are 4 ways to increase the chances of effectiveness using IFC? </li></ul>
    40. 40. IFC advantages & disadvantages <ul><li>Advantages </li></ul><ul><ul><li>1. More comfortable than a TENS unit </li></ul></ul><ul><ul><ul><li>a. Medium-frequency currents meet with less skin resistance than low frequency currents; TENS uses low frequency currents </li></ul></ul></ul><ul><ul><li>2. Stimulates tissues deeper than a </li></ul></ul><ul><ul><li>TENS unit </li></ul></ul><ul><ul><li>3. Larger coverage area than TENS </li></ul></ul><ul><li>Disadvantages </li></ul><ul><ul><li>1. Eliminates pain; doesn't deal with </li></ul></ul><ul><ul><li>cause of the pain </li></ul></ul><ul><ul><li>2. May mask more serious problems </li></ul></ul><ul><ul><li>3. Few portable units available </li></ul></ul><ul><ul><li>4. Sometimes becomes a panacea </li></ul></ul>
    41. 41. IFC: Indications & Contraindications <ul><li>Indications </li></ul><ul><ul><li>1. Acute pain </li></ul></ul><ul><ul><li>2. Chronic pain </li></ul></ul><ul><ul><li>3. Muscle spasm </li></ul></ul><ul><ul><li>4. Pain that covers a large area </li></ul></ul><ul><li>Contraindications </li></ul><ul><ul><li>1. Do not use on a person who has: </li></ul></ul><ul><ul><ul><li>a. Implanted pacemaker </li></ul></ul></ul><ul><ul><ul><li>b. History of heart disease </li></ul></ul></ul><ul><ul><li>2. Do not treat transthoracic area </li></ul></ul><ul><ul><li>3. Discontinue if skin irritation develops </li></ul></ul>
    42. 42. IFC: Precautions <ul><li>Precautions </li></ul><ul><ul><li>1. Be cautious when using IFC over: </li></ul></ul><ul><ul><ul><li>a. Impaired sensation </li></ul></ul></ul><ul><ul><ul><li>b. Skin lesions (cuts, abrasions, new skin, recent scar tissue, etc.) </li></ul></ul></ul><ul><ul><li>2. Use caution when using IFC while driving or operating heavy machinery. </li></ul></ul><ul><ul><li>3. A temporary decrease in pain does not mean the cause of the pain has gone. </li></ul></ul>
    43. 43. Application Parameters: IFC <ul><ul><li>Adjust pulse rate settings for specific injury </li></ul></ul><ul><ul><li> a. For acute pain </li></ul></ul><ul><ul><ul><ul><li>i. Use a high pulse rate of 80 – 200 pps </li></ul></ul></ul></ul><ul><ul><ul><ul><li>ii. Pain relief is almost immediate </li></ul></ul></ul></ul><ul><ul><ul><ul><li>iii. Lasts only a few minutes to 1 hr </li></ul></ul></ul></ul><ul><ul><ul><li>b. For chronic pain </li></ul></ul></ul><ul><ul><ul><ul><li>i. Use a low pulse rate of 1 – 5 pps </li></ul></ul></ul></ul><ul><ul><ul><ul><li>ii. Pain relief may take ½ hr </li></ul></ul></ul></ul><ul><ul><ul><ul><li>iii. May last 6 – 7 hr </li></ul></ul></ul></ul><ul><ul><li>Target or vector </li></ul></ul><ul><ul><ul><li>a. Pain that is easily identifiable and pinpointed </li></ul></ul></ul><ul><ul><ul><ul><li>i. Use target or vector buttons to move spot </li></ul></ul></ul></ul><ul><ul><ul><ul><li>where current intersects to area directly </li></ul></ul></ul></ul><ul><ul><ul><ul><li>over pain </li></ul></ul></ul></ul><ul><ul><ul><li>b. Pain that is hard to pinpoint </li></ul></ul></ul><ul><ul><ul><ul><li>i. Use dynamic vector </li></ul></ul></ul></ul>
    44. 44. Application Parameters: IFC (cont.) <ul><li>--Length of application: 20 – 30 min </li></ul><ul><li>--Frequency of application: Once or twice daily, as needed for pain </li></ul><ul><li>--Duration of therapy: Use until IFC is no longer effective. </li></ul>
    45. 45. Review <ul><li>What are the 3 advantages of IFC? </li></ul><ul><li>What are the 4 disadvantages of IFC? </li></ul><ul><li>What are the 4 indications for IFC? </li></ul><ul><li>What are the 4 contraindications for IFC? </li></ul><ul><li>What are the 4 precautions for IFC? </li></ul><ul><li>What’s the pps range to treat acute pain? Chronic pain? </li></ul><ul><li>When should vector or target modes be used during IFC treatments? </li></ul><ul><li>What are the length, frequency, and duration of IFC treatments? </li></ul>