11/16/2024 10:16 AM
NURS 2245: Exam 2 Exam Study Guide.
Dysrhythmias originating in the atria - answer✔premature atrial contractions
paroxysmal supra ventricular tachycardia
atrial flutter
atrial fibrillation
premature atrial contractions - answer✔rate: depends upon underlying rhythm
rhythm: usually regular except for PAC
pacemaker site: ectopic sites in atria
P waves: occurs earlier than expected
PRI: varies dependent on foci of impulse
QRS: usually normal
paroxysmal supra ventricular tachycardia - answer✔rate: 150-250 bpm
rhythm: regular
pacemaker site: atria (outside SA node)
P waves: often buried in preceding T wave
PRI: usually normal
QRS: usually normal
adenosine (adenocard): action - answer✔slows conduction through AV node
interrupts re-entry
will not convert a flutter or a-fib
**given rapidly: IVP, followed with saline flush
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adenosine: S/E - answer✔brief period asystole
flushing
HA
lightheadedness
dizziness
nausea
SOB
rarely: chest pain
atrial flutter - answer✔rate: atrial, 250-350 bpm
ventricular rate: varies
rhythm: usually regular
pacemaker site: atrial (outside SA node)
P waves: F waves are present
PRI: usually normal
QRS: usually normal
Atrial Fibrillation (A-Fib) - answer✔rate: atrial rate: 350-750 bpm
ventricular: varies
rhythm: irregularly irregular
pacemaker site: atrial (outside of SA node)
P waves: none discernible; f waves present
PRI: none
QRS: normal
mechanism of A-fib - answer✔structural &/or electrophysiologic abnormalities alter atrial tissue
promoting abnormal impulse formation
caused by diverse mechanisms
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mechanisms: not completely understood
AF is the common rhythm seen - the end result so to speak
Atrial Fibrillation (A-Fib) extra cardiac factors - answer✔HTN
obesity
sleep apnea
hyperthyroidism
alcohol
drugs
atrial structure abnormalities - answer✔fibrosis
dilation
ischemia
hypertrophy
atrial electrical abnormalities - answer✔increase:
heterogeneity
automaticity
decrease:
conduction
action potential duration
abnormal: Ca ++ handling
Treatment of A-fib and a-flutter - answer✔rate control
prevent thromboembolism
rhythm control by:
chemical
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direct current cardioversion
catheter ablation
rate control - answer✔beta blockers: LOL
calcium channel blockers: verapamil, diltiazem
digoxin
amiodarone
Diltiazem (Cardizem): action - answer✔inhibits movement of Ca across cardiac and arterial
muscle
slows cardiac conduction
decreases contractility
dilates coronary arteries
Diltiazem (Cardizem): uses - answer✔control rapid ventricular response, Afl, Afib, SVT
administration of Diltiazem - answer✔IV infusion then oral
Interventions for Diltiazem - answer✔monitor VS
cardiac monitor
stop if:
medications: prevent thromboembolism - answer✔vitamin K agonist: warfarin (Coumadin)
heparin or enoxaparin (Lovenox)
Direct thrombin inhibitor: Dabigatran (Pradaxa), rivaroxaban (Xarelto), apixaban (Eliquis)
Vitamin K agonist: Warfarin (Coumadin) - answer✔target INR: 2.0 to 3.0
unless age > 75: 1.6-2.5
antidote:
heparin or enoxaparin (Lovenox) - answer✔until therapeutic warfarin OR when surgical
procedures
Target PTT:
Antidote:
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