EXIT N493 - Quiz 3 Study Guide.

 Cardiac monitor = 1 angle of the heart
 ECG = views all angles of the heart
 1 Small Box = 0.04 sec
 1 Big Box = 0.20 sec
 5 Small Boxes = 1 Big Box
 Repolarization = Resting
 Depolarization = Contracting
 Intrinsic rates of the conductive system:
o SA Node working = 60 – 100 times/min
o AV Node working = 40 – 60 times/min
o Purkinje Fibers working = 20 – 40 times/min



NORMAL SINUS RHYTHIM
 Calculating HR: 60 – 100
o Count # of R’s
o Multiply by 10
 If AV node stops working HR: 40 – 60
 ST segment always has to be at the isoelectric line, any changes indicates damage to heart
o Up : Acute damage (MI)
o Down : Old damage (ischemia)
 Always need to have:
o 1 P wave
o 1 QRS interval
o 1 ST segment
o R-to-R equal

Description Duration
P wave Atriums Depolarization 0.6 – 0.12
PR interval Electricity from SA to AV node 0.12 – 0.20
QRS complex Ventricle Depolarization < 0.12 secs
T wave Ventricle Repolarization 0.16

, SINUS BRADYCARDIA
Notes:
 Rate < 60
 Regular rhythm
 Need to have
o 1 P wave
o 1 QRS interval
o 1 T wave

Causes:
 Sleeping
 Carotid sinus massage
 Valsalva maneuver
 Hypothermia
 Vagal stimulation
 Healthy individual (Marathon runner)
 Taking certain medication (Beta-Blockers, Calcium Channel Blocker)
 Certain diseases:
o MI
o  ICP (intracranial pressure)
o Hypothyroidism

Signs/Symptoms: Patient can be asymptomatic or symptomatic
 Fatigue Interventions/Treatment:
 Weakness  If Symptomatic & STABLE (vitals abnormal):
 Syncope o Cardiac monitor
 Dizziness o Determine underlying cause
 Pale o Medications: if CANNOT determine underlying
 Cool skin cause
 Lethargy
 Atropine 0.5 mg IV push
 SOB
 If Symptomatic & UNSTABLE (vitals abnormal):
 Confusion
 Hypotension o PACER (for slow HR with pulse)
 Chest pain (due to  tissue perfusion)

, SINUS TACHYCARDIA
Notes:
 Rate > 100
 Regular rhythm
 Need to have:
o 1 P wave
o 1 QRS interval
o 1 T wave

Causes:
 Fever
 Exercise
 Pain or fear
 Anemia
 Hypoxia
 Dehydration or Fluid volume deficit
 Anxiety
 Caffeine Interventions/Treatment:
 Elicit drugs  If Symptomatic:
 Hypoxia o Cardiac monitor
 Electrolyte imbalances o Determine underlying cause only, no electricity
 Taking certain medication (Albuterol, Atropine, Epi, Norepi) o Medications:
 Certain diseases:  Beta-Blockers (slows HR only)
o Heart failure  Be careful with asthma patients
o Pulmonary embolism o Asthma patients need to take selective B-Blockers
o Hyperthyroidism
Beta-Blockers
Signs/Symptoms: Non-Selective: 1st generation Selective: 2nd generation
 Anxiety  Block both beta 1 (β1) &  Block only beta 1 (β1)
 Palpitations beta 2 (β2) receptors receptors
 SOB/dyspnea o Affect lungs & o Affect only the
 Chest pain (due to  tissue perfusion) heart heart &  CO
 Propranolol  Metoprolol
 Nadolol  Acebutolol
 Timolol  Bisoprolol fumarate
 Penbutolol  Esmolol
 Sotalol Hydrochloride  Betaxolol
 Pindolol  Acebutolol