UNIT 2 Care of Patients with Dysrhythmias Flashcards
generate electrical impulse.
automaticity
respond to electrical impulse.
excitability
transmit electrical impulse
conductivity
shorten fiber length in response to electrical impulse
contractility
the pacemaker of the heart with an average rate of 60-100 bpm.
SA node
gatekeeper of the heart
av node
atrial depolarization
P Wave
ventricular depolarization
QRS complex
ventricular repolarization
T wave
how many seconds is a big block?
0.20 sec
how many seconds is in a small block?
0.04 sec
how many big blocks are in a 6 second interval ?
30 big blocks
what is the most reliable way to measure the HR?
apical pulse
the initial positive deflection
R wave
the negative deflection following the R wave
S wave
the first downward wave of the QRS complex. (often absent)
Q wave
- determine the heart rate
- determine the heart rhythm (regular or irregular)
- analyze the P waves
- measure the PR interval
- measure the QRS complex
- interpret the rhythm
rhythm analysis
______ rhythm impulse originated in the SA node
sinus
- Heart rate 60 to 100 bpm
- atrial and ventricular rhythm is regular
- P waves present with each QRS complex
- PR interval is 0.12 to 0.20 (3 - 5 small blocks)
- QRS is 0.04 to 0.10 (1 - 2.5 small blocks)
criteria of a normal sinus rhythm
_______ are caused by disturbances…
- electrical conductivity and mechanical response
- impulse formation
- impulse conduction
- combination of several factors
dysrhythmias (abnormal rhythms)
bpm greater than 100
tachycardic dysrhythmias
bpm less than 60
bradycardic dysrhythmias
- P wave present
- bpm greater than 100
- caused by fever, dehydration, stress and drugs
- symptoms (if any): decreases CO, consider workload on heart
- nursing intervention: oxygen, identify the cause*
sinus tachycardia
assess patients with dysrhythmias for decreased ___ ____ _________. you have to assess cap refill, pulse strength, skin, intake and output, change in mental status and BP.
cardiac output
- P wave present
- bpm less than 100
- excess vagal stimulation
- decreased speed of conduction
- may decreased BP ( esp in coronary arteries) decreased CO could also mean ischemia so give O2.
- assessment: signs of poor perfusion, and CO
- nursing interventions: identify possible cause, treat cause, apply O2, atropine 0.5 to 1 mg, and pacemaker
sinus bradycardia
how do you tell if atropine 0.5 to 1 mg is working to treat sinus bradycardia?
increased cardiac output
sympathetic _____ up HR and heart contractility
speeds up
parasympathetic _______ down HR and heart contractility.
slows down
- indistinguishable P wave
- recognized by the rate. above 140 bpm
- causes excessive stimulation from drugs, stress, dehydration, heart failure, thyroid disease, COPD.
- symptoms: usually occur dependent on rate but there are signs of poor perfusion, decreased cardiac output, and chest pain.
- treatment: oxygen administration and adenonsine
- adenonsine : must be on the monitor, given rapidly, physician must be present. Stops the heart for 10-30 seconds and then restarts at a more tolerable pace.
- educate patient on the procedure of giving adenonsine and then attempt to provide SUPPORT person. Educate in great detail. won’t lose consciousness, but the experience is terrifying for them.
supraventricular tachycardia or atrial tachycardia
- aging, obesity, COPD, and cardiovascular are the more prominent contributing factors to this.
- rapid atrial depolarization at a rate of 300 - 600 times per minute.
- rhythm is irregularly, regular. no pattern
- no distinguishable P wave
- symptoms Shob, flustering, light headed, fatigue**
- fibrillation means not contracting or quivering
- cardiac output can decrease by as much as 20 to 30%. the preload is decreased.
atrial fibrillation
- assess for signs of poor perfusion
- assess for anxiety
- assess for clot formation (right side lung, left side brain) and potential for heart failure
- 12 lead ECG
- prevent embolus formation
- plan for prevention of heart failure
nursing process in regards to atrial fibrillation
consistent atrial fibrillation is treated by controlling the heart rate with administration of _____-______ and ____ ______ ______
beta-blockers, and calcium channel blockers.
- anticoagulants only if medications are unable to get patient out of afib.
people with afib are nearly ___x more likely to suffer a stroke. Stroke is the most serious complication of afib. Afib related strokes are nearly twice as fatal and twice as disabling as non-afib related strokes
5x
____ _____ is a major problem for those with a ventricular rate of 150 bpm or greater.
heart failure
A result of increased irritability of ventricular cells. early ventricular complexes followed by a pause.
- there will be signs of poor perfusion
- look for factors that contribute to the development of PVC’s such as electrolytes, oxygenation, caffeine, and stress.
premature ventricular complexes
when cardiac dysrhythmias are present what are the two electrolytes that you should monitor and asess?
magnesium and potassium
- eliminate or treat the cause
- antidysrhythmias
- consider oxygen administration
treatment of PVC
ventricular tachycardia is _____
lethal
repetitive firing of an irritable ventricular ectopic focus, usually at a rate of 140 to 180 bpm. if present with no pulse must treat with defibrillation and CPR.
- caused by extreme electrolyte imbalances and myocardial infarction.
- assess ABC, LOC, alterations in O2 and CO/perfusion
ventricular tachycardia
ventricular tachycardia is _____ with:
- oxygen
- antidysrhythmics
- cardioversion of stable
- if unstable/no pulse treat as vfib
priority treatment depends on if it is readily available (defibrillation).
treated
a result of electrical chaos in the ventricles.
Ventricular fibrillation
- fatal in 3 to 5 minutes
how do you treat ventricular fibrillation ?
defibrillation and CPR
