Electrotherapy: Iontophoresis Flashcards
The extracellular environment of the body is largely what?
Salt water (NaCl)
In response to ES, NaCl splits into what?
Na+ and Cl-
Na+ will migrate towards the _____
Cathode
Cl- will migrate towards the ____
Anode
Does the cathode attract cations or anions?
Cations
Does the anode attract cations or anions?
Anions
The anode creates a localized accumulation of _____, resulting in a _____ effect (HCl), _____ local water content, with ____ protein density of local tissue and a _____ effect.
Cl-, acidic, decreased, increased, hardening/sclerotic
The cathode creates an accumulation of ____ resulting in a _____ reaction, _____ water content, ____ protein density of loca tissue, ____ effect
Na+, alkaline, increased, decreased, softening/sclerolytic
What is iontophoresis?
A technique in which electric current is used to induce the transcutaneous movt of (-/+) ions across the skin into target tissue
The delivery of a medicinal ion for therapeutic benefit
The medication used for iontophoresis must be both ____ and ____ soluble
Water, lipid
What kind of current must be used in iontophoresis?
DC current
What is electromigration?
The electrical repulsion of ions
What is the most dominant driving force in iontophoresis?
Electromigration
T/f: electromigration needs DC current to provide unidirectional ion flow
True
What is electroporation?
An increase in the porosity (permeability) of the superficial skin in response to ES and may facilitate the movt of ions into the tissue
The skin is naturally _____ which presents a barrier to transcutaneous movt of ions into a solution
Hydrophobic
What is electroosmosis?
The direction of flow of ions from the anode to the cathode
The bulk movt of solute in response to the electric field
For (+) charged ions delivered from the anode, does electroosmosis flow assist or deter transdermal delivery?
Assists in transdermal delivery
For (-) charged ions delivered from the cathode, does electroosmosis assisted or deter the delivery of ions?
Deter
What is the primary resistance to drug penetration in iontophoresis?
Skin
What are some areas of decreased resistance?
Sweat glands
Sebaceous glands
Hair follicles
Imperfections in the skin (wounds, tubes, etc)
Who has to bring the meds for iontophoresis?
The pt
Are iontophoresis results immediate?
No, it shows results further down the road
How can we communicate to the pt that iontophoresis is effective when results aren’t immediately noticeable?
Correlate to fxn (ie. you can do___ now and you couldn’t before)
T/f: when pts get better faster, we may get reimbursed at a higher rate
True
What is a common OTC option for iontophoresis for reducing inflammation?
Acetic acid (vinegar)
T/f: if the medication doesn’t need a prescription, we can keep it in the clinic
True
What pt population would benefit from iontophoresis to reduce hyperhydrosis? Why?
Amputees bc of the sweat the builds up in the prosthetic and poses a risk for skin integrity
Can iontophoresis reduce hyperhydrosis?
Yes!
What are the clinical implications for iontophoresis?
Inflammation
Analgesia
Scar modification
Wound healing
Gouty arthritis
Calcium deposits
Fungal infections
Edema
What meds can be used in iontophoresis for inflammation?
Dexamethasone sodium phosphate (-)
Ketoprofen (-)
Hydrocortisone (not really tho bc it’s too big of molecules to pass through)
If dex is a negative drug, does the anode or cathode have to be used to push in the med?
Cathode
What is the most common med used in iontophoresis for inflammation?
Dexamethasone sodium phosphate
What meds can be used in iontophoresis for calcium deposits or bone spurs?
Acetic acid (-)
If acetic acid (vinegar) is negative, do we use the cathode or anode to drive in the med?
The cathode
What meds can be used in iontophoresis for scar adhesions?
Potassium iodide (-)
If potassium iodide is a negative med, do we use the cathode or anode to drive in the med?
The cathode
What meds can be used in iontophoresis for inflammatory arthritis/Gout?
Lithium citrate (+)
If lithium citrate is a positive med, do we use the cathode or anode to drive in the med?
The anode
What meds can be used in iontophoresis for pain?
Lidocaine hydrochloride (+)
If lidocaine hydrochloride is a positive med, do we use the cathode or anode to drive in the med?
The anode
What meds can be used in iontophoresis for muscle/joint pain?
Salicylates (sodium salicylate solution (-))
If sodium salicylate solution is a negative med, do we use the cathode or anode to drive in the med?
The cathode
What meds can be used in iontophoresis for skeletal muscle spasms/myositis?
Magnesium sulfate (+)
If magnesium sulfate is a positive med, do we use the cathode or anode to drive in the med?
Anode
What can be used in iontophoresis for hyperhydrosis?
Tap water
What are potential adverse reactions to iontophoresis?
Allergic reaction (latex or drug)
Skin redness (errythema)
Burns
Adhesive reactions
Electrical insensitivity
T/f: chemical burns can develop under either electrode in iontophoresis as a result of an acidic reaction at a pH too low or an alkaline reaction at a pH too high
True
Are acidic or alkaline reactions the more common cause of burns with iontophoresis? Why?
Alkaline reactions are more common bc of the accumulation of sodium hydroxide under the cathode
How can we reduce the side effects of iontophoresis?
Cleansing the skin prior to treatment
Saturate the electrode so there is no dry areas
Administer the treatment to intact/undamaged skin ONLY
reduce the current density to aid in pt comfort
If we under saturate the electrode, what can result?
Decreased conduction
What are the 3 forms of iontophoresis?
Standard system
Integrated system
Hybresis
The standard system can deliver up to ____ mA
4
What form of iontophoresis has a disposable low voltage battery with the drug and electrode build into a patch
The integrated system
Which iontophoresis system has a mini rechargeable controller that connects directly to the patch for 3 minutes at 3mAnto rapidly reduce skin resistance and jump starts the drug delivery?
Hybresis system
What type of iontophoresis is an 8 hour wearable treatment with a burst of current to get it started?
The Hybresis system
What should the pt be feeling with iontophoresis unit on?
Just some tingling electrical sensation, but no burning
T/f: it is always necessary to specify the dose that is delivery using iontophoresis
True
What is the dose equation for iontophoresis?
Dose (mA min) = current (mA) x duration (min)
What is the typical clinical dosage of iontophoresis?
40-80 mA min
Is low intensity over a longer time better or is a higher intensity over shorter time better for iontophoresis?
A low intensity over a longer time is the standard of care
What is the process of application of the standard iontophoresis unit?
Select the ion appropriate for the pathology (what med)
ID the appropriate polarity for the selected ion (cathode or anode)
Determine if the pt is allergic to the ion or drug
Select the device producing DC current
Select electrode of appropriate size to maintain current density in the recommended range
Inspect and prepare the area to be treated before application
Evaluate pt sensation
Explain the procedure and expected sensation
Deliver the med into the active electrode and place the active electrode over the target tissue and the inactive electrode 3-4 inches away
Evaluate the skin contact for evenly distributed pressure
Chose the dosage
Slowly increase amplitude to peak without pain
Inspect skin after treatment
The larger the electrode the _____ the treatment site and the ____ amount of drug
Larger, greater
If a pt has decreased sensation, can we use iontophoresis on them?
No!!!!!
How far away should the 2 electrodes be placed?
About 3-4 inches apart
Generally, we should keep the amplitude under what?
2mA and no more than 4mA
T/f: some redness and small bumps after application of iontophoresis is normal and should go away in a couple hours
True
Should we apply heat/ice after iontophoresis?
NO, DO NOT APPLY HEAT OR ICE FOR AT LEAST 8-10 HOURS AFTER THE TREATMENT
What is the application process for the integrated iontophoresis?
Same as the standard except:
- medication in the active electrode, saline in the dispersive electrode
- attach the controller (charging) for 3 min (at 3mA) for a reduction in skin resistance
- remove the controller and leave the patch on for prescribed time
T/f: there are a good amount of studies to tell us if one iontophoresis system is more effective than another
False
What are the contraindications for iontophoresis?
Any of the contraindications for ES (tumor, pacemaker, DVT, sensitivity, pregnancy, etc)
Nerve use and ion that the pt is allergic to
Nerve use on a desensitized areas
Nerve use over a new scar
Nerve allow the metal to touch the skin
Obtunded pts
Always make sure the power is off b4 attempting to remove the electrodes from the pt
What happens if you forget to turn the power off of an iontophoresis unit and remove the electrodes from the pt?
They will feel a shock
T/f: iontophoresis electrodes can be used for multiple sessions
False, they are single use
When would a pt get iontophoresis and not an injection?
If the physician won’t inject that area
If it is painful to inject the area
If the other wants that
What is common area of the body that we will use iontophoresis on bc physicians don’t usually do injections on it?
The medial epicondyle
Can we place iontophoresis electrodes directly over bones prominences?
Yes, but we should explain that it can be more uncomfortable
When a drug is negatively charged, should we use the cathode or anode to drive the med through the skin? Why?
We should use the cathode bc the cathode also has a negative charge and like repels, which will cause the cathode to push the med away from it and into the skin
When a drug is positively charged, should we use the cathode or anode to drive the med into the skin? Why?
We should use the anode bc the anode also has a positive charge and like repels, which will cause the anode to push the med away from it and into the skin
What factors drive the decision on whether to increase or decrease the intensity of iontophoresis?
Pt tolerance and skin reaction
