Iontophoresis (Lecture #4) - Modalities

Question 1

KNOW: Iontophoresis: The utilization of electrical current to induce the movement of ions transcutaneously across skin and into target tissue

Dexamethazon is the most commonly used durg w/ iontophoresis
* It is negatively charged
* We would pair that w/ a negatively charged electrode
* Once we run current through that negatively charged electrode that electrode will drive that negatively charged medication away from it (into our body)

The medications used most w/ iontophoresis:
* Local anesthetics
* Nonsteroidal anti-inflammatory medication
* antibiotics
* anticancer medication
* hormones

Question 2

What anti inflammatory medication is most often used w/ iontophoresis?

Answer 2

Dexamethasome
* It is a glucosteriod

Its used for inflamamtory conditions

Question 3

What conditions do we use iontophoresis for?

Answer 3

1) Tendinopathies
2) Sprains/strains
3) Neuralgia
4) Edema
5) Ischemic skin ulcers
6) Hyperhidrosis
7) Scar tissue
8) Plantar warts
9) Gouty arthritits
10) Calcific tenonitits

MOderate support for use in acute conditions foranti inflammatory medication (think pared w/ deamethasome for inflammatory conditions)

Question 4

What is the physiologic mechanism for iontophoresis? How does it work?

Answer 4

Electromigration: The movement of ions due to repulsion from electrical current polarity
* Think a positvely charged drug that is placed on a positively charged electrode and repelled into the skin

In addition, the electrical current increases cell membrane permeability
* Allows for delivery of medication into body/tissues (most affects are very local to the area - however it can make blood vessels in the area more permabile which means drugs can get in there and move systemically)

Question 5

Is cathode negative or posittive

Answer 5

Negatively charged = attracts positive ions

Question 6

Is anode negative or positive

Answer 6

positive - attracts negatively charged ions

Question 7

Both the cathode and the anode create an ion flow (because one is negative and the other is posititve) and this assists in ion transfer

Question 8

What are the 2 things you need to know before applying iontophoresis?

Answer 8

1) Polarity of the medication being utilized
* Noramlly dexamethazone is given and it is negative in charge - which means we apply this to the electorde that is negatively charged so that it is repelled and pushed into our skin

2) How to ensure good conductivity for drug to be delivered
* We do this by making sure the skin is clear of any lotions, hair, calused skin
* Also making sure we apply the medication correctly to the pad

we typically make sure there are no dry spots on the pad

Question 9

Should dexamethasone be administered on the cathode electrode or the anode electrode?

Answer 9

Dexamethasone = negative
Cathode = negative
anode = positive

Should be put on the cathode becuase it repells it and puts it into the body

Question 10

KNOW: For electordes the treatment area is the absorbent pad of the electorde

we fully saturate the red circle (using all the application all over the red circle to not let the medication get to dense)
* we get a surrenge full of medication and need to fully spread it out in the treatment are to make sure its not to dense in certain areas

Question 11

What equation do we use for Dosage of Iontophoresis?

Answer 11

Iontophoretic Equation

Dosage (mA min) = current (mA) * Duration (min)

NOTE: this is direct current (not bursts or anything)

mA = amplitude / intensity

Question 12

What is a typical dosage of Iontophoresis?
* How long does it take to deliver this dosage?

Answer 12

Typical dosage = 20-80 mAmin
* However, there is no optimal dosage established

Takes 10-15 minutes

Question 13

Should the pollarities between the pad and the medication be different or the same?

Answer 13

Polartities should match so that it repells

Question 14

KNOW: The entire patch should be wet, but not leaking or dripping

Question 15

Clinical procedure for iontophoresis:

Selector to confirm appropriate patient selection
* Clear of precuations / dontraindications

Identify polarity of the medication and delivery electorde to be used (if medication is negative than the electorde should be negative)

Confirm pt is not allergic to medication

Select appropriate device
* Patch (more common because it does not take away from treatment time - can do other stuff while the patch is on)
* Hand-held vs wall plug in unit
* NOTE: one is not better than the other - just the amount of energy / current you’re going to put into the pt

Select appropriately sized electrodes

Inspect and clean area
* Alcohol or soap / water
* Make sure area is dry

Prepare electrodes

Place active electrode over target area (electrode w/ medication)
* Negative charged medication = black lead
* Positively charged meidcation = red lead
* Want to ensure polarity is the SAME as the medication (repell medication into the body)

Place inactive electrode away from active electrode (this is the electrode w/ the saline on it)
* saline has both positive and negative ions in it - not much of anything here is going to happen
* Place this electide <2x the electode diameter away
* ** Ensure polarity is opposite of the medicatiom

• Enter in appropriate parameters (duration / amplitude)
• Slowly increase to peak amplitde
• Following treatment:
• Turn off unit
• remove electrodes/patch
• inspect skin, assess response
• Document

Question 16

How far away should the electrode w/o the medication be away from the medication one?

Answer 16

<2x the electrode diameter away

Question 17

What should the polarity of the electrode w/o the medication on it?

Answer 17

Opposite the medication

Because remember - the electrode w/ the medication was the same polarity which would repell the medicatoin

Question 18

Saftey considereations from iontophoresis:

Adverse affects from current (polarity)

Theramal injury
* electral burn - this is if intensity is too high or amplitude is to high
* Skin irriattion (redness, itching, tinging)

Allergic skin reaction

Skin inspection must be done everytime

Keep an open line of communication w/ pt

Question 19

Precautions for iontophoresis:

Answer 19

Impared sensation: w/ the exception in wound healing, microcurrent or low amplitude)
* Note this is a precaution because the odds of skin damage are really low w/ this
* We can decrease the amplitude to really low

Poor communication, impaired cognition
* we would utilize the patch for this (very low risk for adverse affects)

Cardiac dysfunction: the iontophoresis could increase BF in that area which would mess up other blood flow
* Arrhythmias, uncontrolled HTN
* Epilepsy, seizure disorders (just having wires on someone w/ this is bad because of strangulation - patch more effective) - electrical current into someone w/ a seziure disorder has the abaility to generate some weird nerve conduction pulse that could trigger a seziure

Consent from physician in apply in area of neoplasm or history of neoplasm
* Dont want to send BF to this area

Compromised skin
* Avoid except wound healing (can use it for wound healing)

Question 20

Contraindications:

Answer 20

Locally:
* Tissue vulnerable to hemorrhage / hemotoma
* Cervical regions in pts w/ history of stroke / seizures
* IN room or area near diathermy or other electromagnetic radiation devices (could be an interaction between the two)
* Pace maker (Trunk or heart region)
* Pregnancy (lumbopelvic, abdominal region)
* Anterior neck
* Phernic nerve, eyes, reproductive organs (avoid area of phernic n or urinary bladder stimulations)
* Areas of PVD or DVTActive osteomyeltitis
* Hemorrhage

Question 21

Documentation
* Medication utilized (and its polarity)
* Treatment area
* Type of iontophoresis method used
* Amplitude, Duration, Total Dosage
* Skin inspection results (before and after)
* Any other adverse results?

Question 22

Here you can see that the red lead it attached to the treatment pad. What does this tell us about the medication?

Answer 22

Red lead = positive
Medication must = positive (because they should match so that it repells)

Question 23

This is an example of what the pad could look like