Ionto Flashcards
ionto
method of delivering med ions through intact skin
alternative to IV or parenteral delivery
how does ionto work?
direct current pushes meds into dermis and tissue using coulombs law of like charges repelling
general types of meds used in ionto
anti inflammatory
anesthetic
prescription
advantages of ionto over injection
no trauma to skin from puncture - decreased infection risk
less meds into blood supply - less systemic effect
relatively painless
direct current
uninterrupted flow of electricity in one direction in circuit
disassociation
compounds placed in a solution disassociate into positive and negative ion components and more +/- state
ion pole attraction
positive cations will be attracted to the negtaive pole/cathode and repelled from positive pole anode
cathode
negative pole
attracts positive and repels negative
anode
positive pole
attracts negative and repels positive
hydrolysis
compound split into ions in water
electrical current causes water to split in OH- and H+ which affect pH
the anode creates what pH reaction and why?
acidic reaction
H+ are repelled from positive anode to skin making it more aciidic
the cathode creates what pH reaction and why?
OH- are repelled from negtaive cathode and into skin creating basic reaction
three mechanisms of movement of ions into the tissue
- electrical repulsion of charges
- electroporation increasing openings in skin surface
- electroosmosis: movement of water and sodium towards cathode creating a stream ions move on
how much current through anode vs cathode
in a complete circuit, the same amount of current flows through both
dispersive electrode
larger than the active electrode to decrease current density at that electrode
reduces risk of discomfort or skin irritation
chemistry under the electrode in ionto
electrodes repel hydrolyzed ions of the same charge, changing the pH at the skin as ions build up in number
can cause irritation or burns
is negative pole or positive pole delivery stronger? Which should you use a smaller amplitude current with?
negative pole is stronger and should use a smaller amplitude over a longer period of time
if drug dissociates into a relatively negative charge, which pole should the medication be placed on?
negative pole or cathode because this pole will repel the medication and push it into the tissueg
if a drug dissociates into a relatively positive charge, which pole should it be placed on?
positive pole or anode because this pole will repel the medication and push it into the tissue
active electrode
treatment electrode containing the drug
monopolar set up
why can ionto only be used with ionic solutions?
the cathode and/or anode only repel ions which is the mechanism for getting the medication into the tissue
negatively charged medications include:
dexamethasone
acetic acid
sodium chloride
potassium iodide
criteria for ionic medications which can be used with ionto
charged ions produced
relatively small ions w molecular weight <8000 daltons
medications in a solution
should only be used on surface tissues
why is direct current used in ionto?
it creates unidirectional, constant flow of medication
be careful of negative side effects like pH changes due to polar effects
side effects of negative pole/cathode/black electrode
alkaline reaction or burn
depolarization
proteolysis and tissue softening
bacteriostatic
side effects of positive pole/anode/red electrode
acid reaction or burn
hyperpolarization
proteoscleriosis and tissue hardening
increased healing
which factors affect current amplitude that should be used?
patient tolerance
polarity of active electrode
size of the active electrode
duration of treatment
dosage of treatment means:
amount of charge that is delivered which has a direct relation to the quantity of ions delivered because the charge is delivering the dose
calculate dosage
dosage mAmin = current mA x time min
eg 4mA x 10 min = 40 mAmin
typical PT treatment dosage of ionto is:
40-80 mA*min
relationship of duration and magnitude of current in ionto
duration is inversely proportional to magnitude of current
longer delivery time means a smaller current magnitude
cathode maximum current density
.5 mA/cm2
calculated based on electrode size/area and current amplitude
negative pole is stronger
anode maximum current density
1 mA/cm2
calculated based on electrode size/area and current amplitude
will adding more drug to the electrode increase delivery?
NO
ionto is current limited and drug delivery is determined by current amplitude and duration
can you mix drugs on ionto electrode?
no, creates competition for which is delivered and reduces effects of both
competing ions
ion present in the electrode of a solution with the same change as the therapeutic ion being delivered
they compete with therapeutic ions to be delivered through the skin
decrease efficiency of delivery, especially with smaller more mobile ions like CL-
you should increase or decrease blood flow while using ionto?
decrease blood flow to systemic areas
we want to keep medication in the general area and not increase circulation systemically
clinical applications of ionto
size limited area
surface level depth
localized conditions so electrode can cover area
drug penetration factors
type of drug
size and location of structure
current dosage
current density
skin thickness
adipose tissue
considerations of electrodes in ionto
don’t place electrodes too close to avoid skin irritation and burns from current bridging
redness and blistering under electrode with drug should disappear within minutes to hours, if not pt is not tolerating tx
use lotion or aloe to assist skin recovery
In which part of the skin is it easiest for a drug to penetrate?
pores, hair follicles, oil glands
buffer
substance that controls pH changes
binds and neutralizes both acidic and basic ions
controls pH and allows greater treatment dosage by decreased risk of burn or irritation
indications for ionto
superficial location
inflammation
scarring
Ca deposits
myositis ossificans
antifungal/wound healing/infected wounds
trigger points
contraindications to ionto
cancer
pacemaker
pregnancy
implanted electrical device
decreased skin sensation
residual skin irritation from previous treatment
dexamethasone
most commonly used ion in ionto
negative ion
decreases acute inflammation by inhibiting inflam response of WBC
half life of 36-72 hours
use every other day
acetic acid
second most popular ion
negative
used for calcium deposits or chronic tendonitis causing scarring
breaks down insoluble ca deposits into soluble compounds to allow healing
delivered 3x week for 3-6 weeks
sodium chloride
negative ion used at cathode
scar tissue softening and mobilization
interacts with cross binding of collagen in scars to make them softer
potassium iodide
negative ion used at cathode
scar tissue softening and mobilization
interacts with cross binding of collagen in scars to make them softer
Kl contraindicated to
normal response to iontophoresis
skin will be pink under electrode and fades over hours
sweat retention vesicles form as very small blister like appearance that resorb with time
buffered delivery of ionto
competing ions are eliminated by buffer allowing optimal delivery of medication with derceased skin irritation and competition
side effects of glucocorticoids like dexamethasone
contribute to tissue breaksown of muscle, tendon, bone, collagen
reduce body’s production of these hormones with continued use
leave one recovery day between uses
effects should be seen in 3-4 treatments
salicylate
anti inflamatory
inhibits biosynth of prostaglandins
indicated for bursitis, tendonitis
positive ions used in ionto
lidocaine
lidocaine
positive ion
blocks transmission of impulses of peripheral nerves for anesthetic effect to tissue
loss of sensation increasing risk of burn, used low current
use to decrease pain for interventions
opioids and ionto
experimental
not administered over site, instead as slow continuous stream in blood for post op pain
work w Dr
works on peripheral opioid receptors
treat soft tissue mineralization
acetic acide from cathode
use for myositis ossificans over 3 weeks
lithium in ionto
delivered from anode
demineralizing urate deposits occurring with gout
wounds and ionto
ionto can help with infection or facilitate healing with zinc oxide at positive pole
accelerate tissue growth
edema and ionto
use hyaluronidase enzyme to increase permeability of connective tissue
draw out excess fluid which is dispersed into vascular and lymphatic systems
scar tissue adhesions and ionto
iodine for antimicrobial effects
sclerolytic effects
delivered at negative pole over scar tissue contraindicated due to decreased sensation
ionto for hyperhidrosis
apply cathode over affected areas followed by anode with tap water
causes keratin plugs in sweat glands
use 8-20 days as needed and must be repeated
