Exam 1: dysrhythmias, SC injuries, pacemakers, chest tubes Flashcards
normal sinus rhythm
indicates that the electrical impulse sent from the SA node is being adequately transmitted following the normal conduction pathway
criteria for NSR (rate, rhythm, p wave, PR interval, QRS complex)
- rate 60-100
- rhythm: regular
- p wave: one consistently shaped p wave before QRS
- pr interval: 0.12-0.2 seconds
- QRS complex: <0.12 seconds
causes of sinus arrhythmia
respiratory patterns, digitalis, morphine
s/s of sinus arrhythmia
HR increases during inspiration and decreases during exhalation
cardiac output formula
heart rate x stroke volume
sinus dysrhythmia
originates in the SA node + conducted through normal pathway
bradycardia strip presentation
- rate: <60
- rhythm: regular
- p wave: normal
- pr interval: 0.12-0.2 seconds
- QRS: <0.12 (wdl)
causes of bradycardia (NOT MEDS)
- MI
- vagal stimulation (suctioning, Valsalva maneuvers)
- neuro disorders
- hypothyroidism
- prolonged hypoxia
meds that cause bradycardia
- acetylcholine
- amiodarone
- beta blockers
- calcium channel blockers
- digitalis
- lithium
bradycardia: impact on client
- assess CO
- symptomatic: unable to complete ADLs w/o fatigue or SOBm may have syncopal episodes
interventions for bradycardia
- implement fall risk
- d/c meds causing bradycardia
- administer atropine
- apply O2
- temporary pacing
tachycardia strip presentation
- rate: >100
- rhythm: regular
- p wave: normal
- pr interval: 0.12-0.2 seconds
- QRS: <0.12 (wdl)
causes of tachycardia
- physical activity
- anxiety
- fever
- pain
- stress
- anemia
- hypoxemia
- hyperthyroidism
- compensatory response to decreased cardiac output/BP (shock)
- dehydration
- infection
- heart failure
- illicit drugs
- caffeine
- nicotine
atrial dysrhythmias
abnormal electrical activity that results in stimulation outside the SA node
premature atrial contractions (PACs)
benign cardiac rhythm occurrence that causes the heart’s electrical conduction system to activate an early heartbeat/impulse from one of the two atrial chambers
causes of PACs
- stress
- cardiac irritability
- anxiety
- fatigue
- inflammation
- infection
- alcohol
- tobacco
- caffeine
s/s of PACs
- usually asymptomatic
- sometimes palpitations
supraventricular tachycardia (SVT)
impulses originating from above the AV node that cause excessive excitability of the atrial tissue
SVT appearance phrase
if you can’t tell if it’s a p or a t, you have to call it an SVT
paroxysmal supraventricular tachycardia (PSVT)
tachycardia of sudden onset and termination
causes of PSVT
- stress
- smoking
- alcohol
- caffeine
- HF/heart disease
- HTN
- DM
- renal disease
- pregnancy
- chronic lung disease
- Wolff-Parkinson-White Syndrome
s/s of PSVT
- rapid ventricular response
- chest pain
- palpitations
- weakness
- fatigue
- SOB
- anxiety
- hypotension
- syncope
1st degree block
- conduction between atrium and ventricles is slower
- pr interval: <0.20
-no threat, no symptoms, no treatment
2nd degree block type 1
- more Ps than QRS
- PR interval gets longer and longer, drops QRS, then restarts
- irregular rhythm
- caused by MI, drugs
2nd degree block type 2
- more Ps than QRS, AV node refuses to allow impulses through
- PR intervals are equal
- rhythm is regular or irregular
- caused by severe MI, CAD, drug toxicity
- treat with pacemaker
3rd degree block
- more Ps than QRS with a pattern
- PR intervals have no pattern to them
- rhythm is regular (usually brady)
- narrow to wide QRS complex
- complete heart block at the AV node, so ventricles take over
- treatment is immediate pacemaker
- caused by MIs, drug levels, electrolyte imbalances
how long should a pr interval, qrs, and qt interval be?
PR: 0.12-0.20 (3-5 squares)
QRS: 0.08-0.12 (2-3 squares)
QT interval: equal to or less than 1/2 the R-R interval
5 steps to interpreting an ECG strip
- determine heart rate
- determine rhythm
- analyze p waves (present, equal, regular, one for each QRS?)
- measure PR interval
- measure QRS duration
indications for ICDs
- pts who have survived ventricular fibrillation (sudden cardiac death)
- pts who have recurrent v-tach
- pts who have risk factors for SCD (big hearts, low EF, cardiomyopathy, long QT intervals)
complicatios for ICDs
- infection during implantation
- delivery of inappropriate shocks
pacemaker education
- assess pulse everyday and keep log
- report s/s of decreased CO
- keep sling on and limit arm/shoulder activity after procedure 1-2 weeks
- keep appt with HCP
- keep incision dry for several days after implantation
- avoid close proximity to high output electric generators
- no MRIs
- avoid standing near anti-theft devices in store doorways, no wand over pacemaker at airport
- carry pacemaker information/medic alert ID at all times
- keep cellphone 6/ away
- do not manipulate generator
