Physical Agents II Exam 1 Flashcards
1
Q
net gain of electrons =
A
negative charge
2
Q
net loss of electrons =
A
positive charge
3
Q
an anode is net
A
positive
4
Q
a cathode is net
A
negative
5
Q
an anode attracts
A
anions: negative charge
6
Q
a cathode attracts
A
cations: postive charge
7
Q
what is voltage?
A
potential difference in distribution of ions
8
Q
if there is increased voltage what happens to the ions
A
they are pushed faster
9
Q
what is current flow
A
the flow of charged particles (ions or electrons)
10
Q
current flow is measured as
A
the number of electrons or ions that pass a certain point in a specified period of time
11
Q
current flow is ______ to electron flow
A
opposite
12
Q
current flow moves from
A
anode to cathode
13
Q
electron flows from
A
cathode to anode
14
Q
Current (I)=
A
voltage/resistance
15
Q
what type of relationship exists between resistance and current
A
an inverse relationship, as resistance increases, current decreases
16
Q
a longer pathway = ______ resistance
A
increased
17
Q
direct current =
A
unidirectional current flow that lasts for at least 1 second
18
Q
in DC which electrode is good for scar tissue
A
cathode
19
Q
DC cathode
A
alkaline effect
attracts hydrogen
breaks collagen bonds by liquifying proteins
promotes fibroblast migration
depolarizes excitable cells
20
Q
DC anode
A
acid affect
attracts oxygen
hyperpolarizes excitable cells
kills bacteria- attracts neutrophils and macrophages
coagulates proteins
21
Q
DC anode
A
acid affect
attracts oxygen
hyperpolarizes excitable cells
kills bacteria- attracts neutrophils and macrophages
coagulates proteins
22
Q
which electrode in DC is good for infectious wounds
A
anode
23
Q
what is alternating current?
A
continuous current flow alternating direction (+/-) at least once per second
the number of electrons that pass in each direction is normally equal
24
Q
what is AC used for
A
stimulation of nervous and muscular tissue
in other countries used for denervated tissue
25
what is pulsed current?
unidirectional or bidirectional current flow with periodic interruptions
lasts for only ms or less
26
what is the most common form of therapeutic e-stim
pulsed current
27
what treatment wouldn't be appropriate to use pulsed current for?
iontophoresis
28
if you have an unbalanced asymmetrical current
you have more time in +/- than the other
29
constant current=
current stays fixed even if resistance or impedance changes: voltage varies
30
constant voltage=
voltage will remain constant and current will change in proportion to resistance or impedance changes
31
elapsed time from onset of stimulus to peak amplitude
rise time
32
elapsed time from peak amplitude to termination of stimulus
decay time
33
total current =
sum of peak amperage, pulse frequency and pulse duration
34
low frequency Hz
0-1000 Hz`
35
medium frequency Hz
1000-10000Hz
russian falls in this category
36
russian frequency =
2500-5000 Hz
37
the higher the frequency the more _____ in muscle is seen
fatigue
38
frequency and recruitment of Type I fibers
10-20 Hz
39
frequency and recruitment of Type II fibers
30-60 Hz
40
in a voluntary contraction which motor units are recruited first
the small, slow, and deep motor units
41
in electrical stimulation which motor units are recruited first
large and fast motor units
42
contraindications to ESTIM
severe cardiac conditions
demand type pacemaker
active osteomyelitis
active bleeding or risk of hemorrhage
carotid bodies/laryngeal/pharyngeal mm
phrenic nerve, eyes, gonads
when AROM is contraindicated
pregnancy (over lumbopelvic region, uterine area or if they have had multiple miscarriages
43
precautions to ESTIM
sensory loss
areas of scarring
thick adipose tissue
severe edema that is water based
over malignancy/neoplasm
open wounds
severe depression
mild disoriented patients
superficial metal
44
transdermal drug delivery using low voltage DC to move ions across a dermal barrier
Iontophoresis
45
how does iontophoresis work to drive ions through the skin
increases the permeability of the stratum corneum
46
how deep down iontophoresis penetrate
3-20 mm
47
what type of current is used for iontophoresis
Direct Current
48
increase in porosity of epidermis in response to E-stim=
electroporation
49
what happens to the skin porosity after E-stim application
temporary increase in porosity
50
what is electromigration and what is it based on
movement of ions through tissue
volume flow not just diffusion
51
human skin has a net ______ charge
negative
52
what is the driving force behind iontophroesis?
repulsion of like charges
53
most common mA minutes for iontophoresis
40mA minutes - 80 mA minutes
54
most units in iontophoresis don't exceed ____ mA for intensity
4 mA
55
the more mA the patient can tolerate the ______ the treatment will be
shorter
56
skin reaction with cathode in iontophoresis
alkaline reaction from sodium hydroxide under the cathode
caustic
57
skin reaction with anode in iontophoresis
acidic reaction from hydrochloric acid under the anode
more comfortable than cathode reaction
58
current density shouldn't exceed ___ for the cathode (-)
0.5mA/cm2
59
current density shouldn't exceed ___ for the anode (+)
1.0mA/cm2
60
how are the electrodes set up for iontophoresis
in a monopolar set up
61
the active electrode is ____
smaller
62
the dispersive electrode is of ______ charge and _____
opposite charge and it is larger than the active electrode
63
which medication is used for inflammation iontophoresis
dexamethasone
negative polarity
64
which medication is used for calcium deposits iontophoresis
acetic acid (acetate)
negative polarity
65
which medication is used for anesthetic iontophoresis
lidocaine
+ polarity
66
which medication is used for scars and iontophoresis
iodine
negative polarity
67
when in the treatment session is iontophoresis typically done
at the end of the session
68
what reaction from iontophoresis should be examined by a physician
a blister
69
when strengthening during E-Stim the MVIC has to be ≥
60%
70
frequency when strengthening
35+ pps
71
phase duration for strengthening
200-300 ms
72
cycle time for strengthening
1:5 ratio of on:off
73
treatment time/dosage for strengthening in E-stim
want 10-20 strong contractions
74
frequency for Russian strengthening
2500 Hz with 50 bps
75
phase duration for Russian strengthening
20O us (determined by bps)
76
cycle time for Russian strengthening
1:5 ratio
77
treatment time for Russian strengthening
want 10-20 good contractions
78
what is a typical progression for E-stim and strengthening/russian strengthening
increasing the amplitude
79
frequency for endurance
<50 pps, we don't want them to fatigue so we want a submax tetanic contraction
80
endurance cycle time should be closer to
1:1
don't need rest time
81
what cycle time should you use if the patient is pretty strong already and you're working on endurance
a 1:3
82
progression for endurance E-stim
cycle time less and less, increase the # of contractions in a time frame, increase sessions/day
83
what don't you need when the purpose for E-Stim is motor control cutaneous
a muscle contraction
84
phase duration for motor control (cutaneous)
< 200 microseconds
85
amplitude for motor control (cutaneous)
sub-motor
86
what muscles should be stimulated for a shoulder subluxation
anterior deltoid and supraspinatus
some say to do posterior delt and supraspinatus
87
what nerve is targeted with E-stim and orthotics (AFOs)
the fibular n
88
how do we reduce spasm with E-stim
reciprocal inhibition through fatigue
do not use motor point if cutaneous usage
89
cycle time to reduce edema:
1:1, activate the muscle pump
90
what are we preventing when using E-stim to stimulate denervated muscle
keep out fatty infiltrates and atrophy
91
which current type is commonly used for denervated muscle
DC
sometimes AC with a long enough phase duration
92
symmetrical biphasic is good for what:
strengthening, endurance and motor control
93
symmetrical biphasic is not acceptable for ______
wound healing
94
frequency for muscle spasm
50+
95
frequency of 50 should be used when the goal is:
strengthening or edema
96
amplitude should provide tetanic contraction: submaximal when the goal is
endurance, edema and muscle spasm
97
cycle time ratio for edema control and muscle spasm
1:3 to 1:1
98
Russian stimulation is best for ____ and can be good for _______
strengthening, endurance
99
Russian should not be used for
muscle spasm or wound healing
100
amplitude with motor control should always be
activity dependent: enough to cause a contraction after all voluntary movement has occurred
101
High-Volt E-stim is great for
wound healing and muscle spasms, good for edema
102
what is lower when you use High-Volt E-stim
the phase duration
100-200
103
polarity for High-Volt E-stim when used for wound healing
will be wound dependent
104
Electrode Configuration for High-Volt E-stim for wound healing
monopolar
105
Electrode Configuration for High-Volt E-stim for muscle spasm
bipolar
106
Electrode Configuration for High-Volt E-stim for edema when using sub-motor versus a tetanic
monopolar for submotor and bipolar for tetanic contraction
107
DC electrode configuration for wound healing
monopolar
