Care of The Cardiac Patient Flashcards
depolarizing=
contracting
repolarizing=
resting
pacemaker cells that helps the heart function on its own regardless of what the brain does
SA Node
when SA node fires then the HR is
60-100bpm
what node is next in line if the SA node stops working
AV node
when the AV node fires then the HR is
40-60 bpm
if something is wrong with the AV node what fires next
purkinje fibers
when the purkinje fibers fire then the HR is
20-40 bpm
what are the 2 parts of autonomic nervous system
sympathetic and parasympathetic
in sympathetic the heart is beating
fast
in parasympathetic the heart is beating
slow
which nerve responds in parasympathetic
vagus nerve located at the carotid (cranial nerve 10)
starling’s law of the heart
stroke volume is dependent on venous return
if venous return is _______ then stroke volume is _______ and cardiac output is ______
increased; increased; increased
what does the right coronary artery feed
the SA node, right atrium, AV node, and part of the posterior wall
if there is an inferior wall MI what could be blocked
right coronary artery
what does the left main coronary artery bifurcate into
left anterior descending branch and the left circumflex branch
if there is an occlusion at the top of the left main coronary artery what is it called
“widow maker”
what feeds the left atrium
left circumflex branch
what feeds the septum wall
left anterior descending branch
on an EKG how many “big squares” are 1 second
5
on an EKG how many seconds is 1 tiny square
0.04sec
what are the different hardwire monitoring of ECG/EKG
three lead system
five lead system
12 lead system
what are the different telemetry monitoring of ECG/EKG
three lead system
5 lead system
why should you change a 5 lead EKG daily AND date them
pt sweats and the gel is conductive gel, so when pt sweats it has salt in it so the EKG can be obscured
what is the placement for 5 lead EKG
RA (white) LA (black) MCL (Brown) RL (green) LL (red)
for a 5 lead (limb lead) what is lead one
RA (-) to LA (+)
for a 5 lead (limb lead) what is lead 2
RA (-) to LL (+)
for a 5 lead (limb lead) what is lead 3
LA (-) to LL (+)
*Legs are ALWAYS positive and V1 (MC) is always negative, so aVr, aVl, and aVf are all +
flat lines that tell us what is elevated and what is depressed
isoelectric lines
for it to be sinus rhythm what needs to be present
p wave needs to be upright and accompany QRS
P wave should be no longer than ____ boxes
3
PR interval should be no longer than ___ boxes
5
*if longer this should tell you there is a block
QRS interval should be _____ boxes because if wider there is a block
2.5
QT interval should be __-__ large boxes
1-2
atrial depolarization causes
P wave
what are the 2 phases of the P wave
completes right side them moves over to left atrium
ventricular depolarization causes
QRS wave
- initial Q can be present or absent
- a significant Q wave is when it is 1/3 the height of the R wave (major problem) myocardial damage
ventricular repolarization causes
T wave
- slower because we are heading into the resting phase
- ALWAYS an R wave before the T wave
sometimes you see this wave, sometimes you don’t. if you see them its usually associated with repolarization of purkinje fibers
U wave
- if you see it ask if they are diabetic, cardiac hx, taking digoxin, hypokalemic, hypothermic
- mostly seen in slower heart rates <65
what is important about the pause occurring at the AV node (PR segment)
allows time for blood to empty from the atrium into the ventricle
what is important about the ST segment
line is flat and after that it will show us if the T wave is inverted, depressed, or elevated
T wave inversion=
ischemia
ST depression=
injury
ST elevation=
infarction
ST segment below the isoelecto line
ST depression= injury
*if it looks like a label it is digitalis effect
give oxygen and ask about meds
ST segment above the isoelectro line
ST elevation= infarction
- tx is MONA
- even if pt states they are not having chest pain you still get 12 lead EKG and call physician
what is MONA
morphine, oxygen, nitroglycerine, aspirin,
then cardiac cath or surgery
what should you do if the T wave is inverted
indicates ischemia so give oxygen and let physician know
originates in the right or left VENTRICLE, does not follow normal conduction path, each ventricle fires separately, these are wide and bizarre shaped
premature ventricular contraction (PVC)
every other beat is a PVC=
bigeminy
*give oxygen
every third beat is a PVC=
trigeminy
a pair of PVC, one is up one is down
multifocal couplet
if pt is having multiple PVCs (>6/min) what should be given
lidocaine
what van V tach turn into
ventricular fibrillation
what is the purpose of a pacemaker
control heart rate when conduction is compromised
paces either the atria or ventricle
single chamber
paces both atrium and ventricle
dual chamber
what is the 3 letter system for pacemaker
first letter= chamber is being paces
second letter= chamber is being sensed
third letter= response to heartbeat
what is important to teach the pt who gets a pacemaker
do not raise affected extremity above shoulder, bend at the knee, or push up for 2 weeks (cause dislodged electrode)
what interval will be wide if pt has a pacemaker
QRS
pt has a pacemaker that shows a spike with no response is
failure to capture
pt has a pacemaker what fires after pt’s own beat is
failure to sense
failure to sense is the most ______ because if fires ______ the pt’s own ______ and if we have electrical impulse after pt own beat it might hit on the ___ wave and could cause an __ on __ phenomenon
concerning; after; beat; T; R on T
what is an indication that pacer wire is dislodged or perforated the myocardium
hiccupping, rhythmic chest wall or diaphragmatic twitching
*must notify physician and monitor pt
what are the 6 steps of rhythm strip analysis
- regularity of R wave
- calculate HR
- identify P wave (upright, present before QRS)
- measure PR interval
- measure QRS complex
- ST depression or elevation
- is there any other unusual occurrence
