ELECTRICAL CURRENT FOR TISSUE HELALING

Transcription

1 ELECTRICAL CURRENT FOR TISSUE HELALING

2 Tissue healing 2 Chronic wound healing (ex. pressure ulcer) faster! Mechanism - attraction of appropriate cell type of area - activation of theses cells by altering cell membrane function - modification of endogenous electrical potential of the tissue in concert with healing potentials. - reduction of edema - enhancement of antimicrobial activity, and promotion of circulation Galvanotaxis ( 전기주성 ) - attraction to the negative pole : activated neutriphil, lymphocyte, platelet, mast cell, keratinocyte, fibroblast negative electrode : inflamed or infected wound healing 을촉진 - attraction to the positive pole: inactive neutriphil, macrophage, epidermal cell positive electrode : to promote healing of wound with no inflammation

3 Tissue healing 3 To enhance fibroblast replication and Increase the synthesis of DNA and collagen by fibroblast (voltage dependent) - proposed mechanism? Injured tissue : positive charge relative to the surrounding uninjured tissue returning to normal only after the wound closes to promote tissue healing through antimicrobial activity - monophasic current ex. Microampere level DC and HVPC - bacterial growth를억제하기위한 ES는 much higher voltage 또는 much longer times 적용 to promote tissue healing by increasing circulation during or after the stimulation

4 Parameter for ES for tissue healing 4 Electrode placement Waveform Polarity Pulse duration Frequency On:off time Current amplitude Treatment time

5 Electrode placement 5 Figure Electrode placement to promote tissue healing.

6 6 Waveform Monophasic waveform HVPC LIDC

7 7 High-voltage pulsed current (HVPC) DC dual peak pulse 장점맥동기간이짧고, 순간전압이높아통증이나조직손상을유발하지않고효과적으로심부조직을자극할수있다. 특징

8 Polarity 8 Polarity of the electrode on or nearest to the wound : wound healing의특정단계, infection or inflammation 유무에따라결정 - Negative polarity: early inflammation stage - Positive polarity : later to facilitate epithelial cell migration across the wound bed negative polarity positive polarity

9 9 Pulse duration : HVPC, 40~100 μs Frequency : 60~125 pps On:off time : off time X Current amplitude - sufficient to produce a comfortable sensation without a motor response - 치료부위의감각이감소되거나이상감각이있을경우에는정상감각부위에먼저 electrode 를적용하여적절한강도결정

10 Edema control 10 Edema formation associated with inflammation : negative polarity HVPC below the threshold for motor contraction microvessel permeability Edema formation caused by poor peripheral circulation due to lack of motion : motor level ES elevation, compression garment 함께사용하면효과적

11 Parameter for ES for edema control 11 ES for edema associated with inflammation ES for edema associated with lack of muscle contraction

12 Iontophoresis 12 transdermal drug delivery를촉진하기위해 low-amplitude DC 사용 : mechanism? Depth of drug delivery : uncertain, 3~20mm - salicyclic acid와 lidocain은 stratum corneum( 표피각질층 ) 투과가능 ma-min : table 8-5, 주로 40 ma-min권장 ionized drug의 continuous delivery를위해 DC 사용, akaline reaction: electrode 아래에서 undesirable chemical change 발생가능.! NaOH (- electrode), alkaline reaction, discomfort, skin irritation, chemical burn to reduce the risk : negative electrode larger, current amplitude decrease HCl (+ electrode) : acidic reaction, less uncomfortable than alkaline reaction Table 8-6

13 Parameter for the application of Iontophoresis 13 Electrode placement and size - drug delivery electrode, dispersive electrode - current density 가 0.5 ma(cathode), 1.0 ma(anode) 를초과하지않도록충분히커야한다. Polarity same polarity as the polarity of the active ion Current amplitude : patient comfort 에의해결정, 4mA 를넘어서는안됨. Treatment time - total treatment dose of 40 ma-min : table 7-7

14 14 Figure hour iontophoresis patch. Figure Hybrid iontophoresis device.

15 15 Figure The molecular structure of dex amethasone sodium phosphate. Figure Electrode placement for iontophoresis

16 Contraindication and precaution for the use of electrical current

17 Contraindication for the use of electrical currents 17 Demand pacemaker or unstable arrhythmias Over the carotid sinus Venous or arterial thrombophlebitis Pelvis, abdomen, trunk, and low back area during pregnancy

18 Precautions for the use of electrical currents 18 Cardiac disease Impairment mentation or impaired sensation Malignant tumor Skin irritation or open wounds Iontoporesis after another physical agent

19 Adverse effects of electrical current 19 Careful evaluation으로 adverse effect 최소화 Burn at DC and AC Skin irritation or inflammation Pain

20 20 Application technique Patient positioning Electrode type Electrode placement

21 Patient positioning Area to be treated, goal of treatment, the device used 에따라환자자세결정 ES for muscle strengthening midline end of the available ROM Positioning strap, cuff weight 활용하여고정

22 Electrode type 22 Electrode most commonly used today Self-adhesive gel coating that serves as the conduction medium disposable and flexible gel : decrease resistance between the electrode and the skin Gel coating start to dry out uneven current density burn Carbon rubber electrode more long-lasting electrode, not self-adhesive Should be cleaned with warm, soapy water and not alcohol Current density 와 electrode size 는반비례 larger electrode : more comfortable than smaller ones cannot target small area

23 Electrode placement 23 Electrode must lie smoothly against the skin without wrinkles or gap self adhesive electrode : maintain good contact other type : flexible bandage 필요, Should not be placed directly over bony prominence distance or spacing between electrodes Document electrode placement using diagram

24 24 General instruction for ES

25 25 Figure Treatment of upper back and neck pain with electrical stimulation.

26 26 Figure A, Electrical stimulation to increase hamstring strength

27 27 Figure B, Electrical stimulation to increase quadriceps strength.

28 28 General stimulations for ES

29 29 General term

30

31 31 Waveform

32 32 Alternating current Continuous bidirectional flow of charged particle equal ion flow in each direction, no pulse charge Frequency, cycle duration Relationship between frequency and cycle duration Frequency, cycle duration 1000~10,000 Hz

33 Medium frequency 33 AC with a frequency between 1000 and 10,000 Hz 2500 ~ 5000 Hz for clinical unit 2개의다른 medium frequency AC 의의해생성된 interferential current의형태로주로사용

34 Continuous current 34 Continuous flow of charged particles without interruption of break Continuous current Direct current(dc) : one direction Alternating current (AC) : two direction

35 35 Interferential current interferential current between two crossed pairs of electrodes ( 4 electrode) An alternating current with a frequency of 5000 Hz interfering with an alternating current with a frequency of 5100 Hz to produce an interferential current with a beat frequency of 100 Hz.

36 Interferential current 36 More comfortable than other waveform, Why? Low amplitude current on skin More total current than pulsed wave form Larger area than other waveform 많은 Animal study 에서 Inflammation 과 ischemia 와관련된 pain 을감소시킨다고하였으나, 특별하게다른효과없다고나타남.

37 37 Premodurated current AC with medium frequency Same form as an interferential current But single circuit and only 2 electrode No advantage of interferential current (lower current amplitude, large area)

38 Pulsed current(pulsatile current) 38 An interrupted flow of charged particle Type Monophasic pulsed current tissue healing and acute edema management application Commonly used High voltage pulsed current(hvpc) (= pulsed galvanic current) A, Monophasic; B, biphasic pulsed currents.

39 Pulsed current 39 Biphasic pulsed current Symmetrical : Asymmetrical : balanced, unbalanced Symmetrical, balanced asymmetrical biphasic current net chare of zero Often little difference between symmetrical and asymmetrical BPC Symmetrical : more comfortable for large muscle group Asymmetrical : for small muscle group A, Symmetrical; B, balanced asymmetrical; C, unbalanced asymmetrical biphasic pulsed currents.

40 Russian protocol 40 Waveform with specific parameter intended for quadriceps muscle strengthening Median frequency AC with 2500 Hz delivered in 50 bursts/second (= medium frequency burst AC)

41 41 Time-dependent parameter Frequency Interphase interval(intrapulse interval) Interpulse interval On:off time Phase duration Pulse duration Ramp up/ramp down Rise time/decay time Wave length

42 Frequency 42 Number of cycles or pulsed per second Measurement unit Hertz(Hz) for cycle Pulse per second(pps) for pulse Monophasic pulsed current with frequencies of 3 pps and 9 pps.

43 Interval 43 Interphase interval (intrapulse interval) Interpulse interval The time between phases of a pulse The time between pulse Interphase interval for a biphasic pulsed current

44 On: off time 44 On time: time during which a train of pulses occurs off time: time between trains of pulses when no current flows Usually only used when ES is used to muscle contraction On time, off time One time: muscle contraction off time : muscle relaxation, needed to reduce muscle fatigue during stimulation session Sequential on and off time to mimic the voluntary contraction and relaxation phases of normal physiological exercise On : off ratio 10sec on : 50 sec off 1:5 on off ratio On:off times for a biphasic current

45 Duration 45 Phase duration Pulse duration Duration of one phase of a pulse μs, ms Time from the beginning of the first phase of a pulse to the end of the last phase of a pulse μs

46 Time 46 Ramp up / ramp down time Rise time/decay time During the on time During any one phase

47 Wavelength 47 The duration of 1 cycles of AC The wavelength of AC is similar to the pulse duration of pulsed current

48 48 Other ES parameter Amplitude (intensity) Amplitude modulation Burst mode Frequency modulation Modulation Phase duration or pulse duration modulation Scan Sweep

49 Amplitude (intensity) The magnitude of current or voltage

50 50 Modulation

51 Burst mode 51 A current composed of series pulsed delivered in groups known as burst

52 Modulation 52 Used to limit neural adaptation to an electrical current Type Amplitude modulation Frequency modulation Phase duration /pulse duration modulation Scan : amplitude modulation of an interferential current Sweep: frequency modulation of an interferential current

53 53 Nerve and electrical current Absolute refractory period Accommodation Action potential Adaptation Chronaxie Depolarization Myelin Node of Ranvier Propagation Relative refractory current

54 54 Unn Figure Unn. Fig. 8-1.

55 55 Medium frequency Continuous current Direct current Alternating current Interferential premodulated current Russian protocole