Exam 1 Flashcards
Treatments for Vfib?
Defibrillation, implantible cardioverter defibrillator, precordial thump, anti arrhythmic drugs - amiodarone, lidocaine
Is Vfib a shockable rhythm?
Yes
Common causes for torsades de pointes
Hypomagnesia, hypokalemia, malnourished and chronic alcoholics, MI
torsades de pointes characteristics
Prolonged qt interval (prolonged vent repolarization). Looks like VT except QRS do “streamer” effect around baseline
Most general way of determining ventricular vs supraventrular arrhythmias?
Supra - narrow qrs
Vent - wide qrs
Difference between vt and Psvt?
•VT –No response to carotid massage –Cannon A waves may be present –Fusion beats may be seen •PSVT –May terminate with carotid massage –Cannon A waves are not seen –Fusion beats are not seen
Difference between PAC and PVC?
PVC has compensatory pause, PAC has a more normal-looking QRS
Characteristics of PVC?
- Wide and irregular QRS complex
- Retrograde or no P wave
- Presence of ‘compensatory pause’
Names of PVC/normal qrs ratios?
–1:1 = bigeminy –1:2 = trigeminy –1:3 = quadrageminy
What if PVCs have different shapes?
They are coming from different areas (irritable foci of the ventricles)
How are PVCs and Vtac related?
Vtac is 3+ PVCs in a row
VTac is how many BPM?
120-200
Treatment for PVC’s?
1mg/kg lidocaine
Treatment for VTac?
Defibrillation and ACLS
Main difference between hypertrophy and enlargement?
Enlargement - Refers to dilatation of a chamber
Hypertrophy - Refers to an increase in muscle mass
Enlargement and Hypertrophy changes
Increase in wave duration
Chamber takes longer to depolarize
Increase in wave amplitude
Chamber can generate more current at a time
Shift of electrical axis
Larger percentage of total electrical current can move through the expanded chamber
Which plane is the axis?
Frontal
Correspond each lead with AVF etc
AVF - 1, AVL - 2, AVR - 3
Match Leads 1-3, AVF etc with corresponding numerical values
1 = 0, 2 = 60, 3=120, AVF =90, AVL=-30, AVR=-150
Best leads to see atrial enlargement
2 and v1
Duration, length of normal P wave
< 4 blocks long, <2.5 blocks high
Hypertrophy generally refers to ______ and enlargement generally refers to ________
Hypertrophy of ventricles, enlargement of atria
Causes of arrhythmias?
- Hypoxia 2. Ischemia and irritability 3. sympathetic stimulation 4. Drugs 5. Electrolyte disturbances 6. Bradycardia 7. Stretch
What is the mnemonic for arrhythmias and what does it stand for?
HISDEBS, treatable factors leading to arrhythmias. Hypoxia, Ischemia/Irritability, Sympathetic Stimulation, Drugs, Electrolyte disturbance, Bradycardia, Stretch (enlargement/hypertrophy)
What is HR when R-R interval is a. 3 large squares b. 4 c. 5 d. 6
a. 100bpm b. 75 c. 60 d. 50
What are 4 basic questions to ask when assessing an EKG?
- Are normal P waves present?
- Are the QRS complexes narrow or wide?
- What is the relationship between the P waves and the QRS complexes?
- Is the rhythm regular or irregular?
Describe PSVT
Normal rhythm but rate is 150-250bpm. May have retrograde R wave in lead 2 or pseudo-R in V1. Usually not indication of underlying cardiac disease, may just be excitement, caffeine or alcohol.
Describe the carotid massage vagal response
Massage of carotid artery stimulates baroreceptors to send reflex response from brain along vagus nerve to the heart to decrease rate at which sinus node fires.
Carotid massage can break what arrhythmia?
PSVT
Describe how to do carotid massage
Pt lying flat w/ neck extended and head to left. Palpate RIGHT artery and apply pressure 10-15s (try left side if right fails).
