cardiac pacemakers Flashcards
what can a pacemaker do?
- initiate a P wave (atrial contraction)
- initiate a QRS (ventricular contraction)
- do both
pacemakers parts
- the generator:power source, usually made of lithium, lasts very long time
- the brain: electronic circuit, programming
- the lead: ran through subclavian
- the electrode: attaches to heart/inside heart
indications
slow rates: bradycardia (symptomatic), Types I-II 2 degree AVB, complete HB, bifasicular blocks(bundle branch blocks), A-fib with slow ventricular response
fast rates: tachycardia (PAT, A-flutter, A-fib)
types of pacing
- transcutaneous (endocardial), done from defibrillator
- epicardial (myocardial) (outside of heart)
- esophageal
- permanent vs. temporary
asynchronous
fixed rate pacing
-only used when first put in to make sure it works for pt
demand/inhibit
fires as needed
capture
causes atrial/ventricular contraction
-pacemaker captured cardiac muscle and made it jump
sense/sensitivity
ability of the pacer to see the electrical impulse of the heart
threshold
least amount of electrical energy to create capture
types of pacemakers
singe channel: only makes P waves OR QRS, external
dual channel: can do both, external
-manipulated by output: milliamps (mA)
sensitivty: millivolts (mV)
milliamps control
movement of electrons
millivolts
amount of energy sent down
failure to capture
not in contact with muscle
- scar tissue forms around it and the shock cant reach the heart muscle
- increase sensitivity
- increase in juice needed
nursing management
- failure to pace
- failure to sense/oversensing
- pacemaker mediated tachycardia
- PVCs
- diaphramatic/ muscle stimulation
patient teaching
- daily pulse check
- incision cleanliness
- avoid lifting, tugging, pulling
- no swimming
- microwaves
- avoid batteries/magnetic fields
- security devices will go off (airplane security)
- wear a “medi-alert” band
AICD (automatic intertnal cardiac defibrillators) indications
those at risk for “sudden cardiac death”
- documented recurrent VT
- structural heart disease
- CAD
- Poor LV function
- cardiomyopathy
AICD placement
endocardial: in abdomen, up to subclavein and into heart
epicardial: sewn mesh around heart
AICD uses 15 jewels because it is in direct contact with the heart
nursing managment
similar to cardiac pacemakers
*in emergency: turning on/off: use doughnut magnet
“on”:high pitched/ random beeps
“off”: constant R-wave tones
-biggest need to know for nurses in emergency: what is activation status? (is it on or off?)
VT:
if on: observe pt. may take a few minutes to kick on
if off or ineffective: follow emergency procedures
Patient teaching
- emotional support
- incisional care
- life-style changes
- driving restricted
- medical alert ID
- Id cards
