Card Set Information
normal PR interval:
0.12-0.20 seconds = 3 - 5 small boxes = less than 1 big box
normal QRS interval
less than 0.12 seconds = less than 3 small boxes
What basic cardiac conduction dysfunction can cause a prolonged PR interval?
e.g. AV block
What basic cardiac conduction dysfunction can cause a shortened PR interval?
: bypass AV node with aberrant pathway between atria and ventricles
What is the basic cardiac conduction dysfunction that causes a prolonged QRS?
ventricular rhythm = rhythm originates in ventricles and not AV/His/Purkinje system
e.g. His-Purkinje block
e.g. aberrant pathway
What are the "shockable" and "non-shockable" ACLS cardiac arrest rhythms?
: VF and pulseless VT
: asystole and PEA
What are the cardiac arrest rhythms?
PULSELESS rhythms: VF, pulseless VT, PEA, asystole
What is the 1st ACLS IV/IO drug for cardiac arrest rhythms?
: 1mg epinephrine
: 0.01mg/kg epinephrine
What are the antiarrhythmic drugs for VFib?
Amiodarone 300mg (kid = 5mg/kg)
What antiarrhythmic drug do you use for VT?
: Amiodarone 300mg (kid = 5mg/kg)
polymorphic VT (Torsades de Pointes) = Magnesium 2mg
Do you "shock" all people with VT?
No: must be ARREST rhythm with PULSELESS VT
What cardiac rhythms make up PEA?
any cardiac rhythm except VFib, VT, and asystole
= any rhythm that does not cause perfusion/pulse
What are the most common causes of PEA?
5 H's and 5 T's:
Hydrogen ions (acidosis)
What are Supraventricular Tachycardias?
= tachycardia with narrow QRS = originates in atrial nodes
re-entry SVT (AV re-entry tachycardia)
multifocal atrial tachycardia
What is the max conductance of the AV node?
What are common AV node blocking agents? What are they used for?
= beta blockers, CCB, digoxin (adenosine, vagal manuevers)
used for rate control with AFib
DO NOT USE with WPW/accessory pathway arrhythmias
What are the vagal maneuvers and what are they used for?
used to treat SVT; increases AV node blockage
= carotid sinus massage (10-15s)
= valsalva maneuver (10s)
= icepack to face (20-30s)
What population do you want to avoid using adenosine? Why?
adenosine can cause bronchoconstriction
How do you use adenosine?
used for transient AV node blockage
used to try to terminate re-entry circuit
short half life (5-10s)
must use rapidly with bolus through large bore IV and immediately flushed with 20-30mL NS
What are typical features of re-entry SVT in kids compared to sinus tachycardia?
faster rate (>220 in infants; >180 in kids)
does not vary with level of activity
has no P-waves
has no prodrome of illness