EKG

Question 1

what is the difference between 3 lead, 5 lead, and 12 lead EKGs?

Answer 1

• 3 & 5 lead: continuous pictures of the heart
  
  • 5 lead: telemetry–>5 wires
  • 3 lead: bedside–>3 wires
• 12 lead: snapshot in time
  
  • 10 wires
  • not continuous

Question 2

what is the time interval from one dark line to another dark line on a strip?

what is the time interval for each individual box on a strip?

Answer 2

• 0.2 seconds
• 0.04 sec (so 5 of these little boxes for each large box from dark line to dark line)

Question 3

PR Interval

Answer 3

• beginning of P wave to beginning of QRS wave
  
  • should be <0.2 seconds
  • if longer than 0.2 seconds, this is first degree AV block

Question 4

ST segment

Answer 4

• from end of QRS complex to end of T wave
• if elevated: STEMI–>infarction
• if depressed: ischemia–>not getting the O2 you need

Question 5

what are the questions to ask when looking at a cardiac rhythm strip

Answer 5

• are there QRS’s?
• is there a “p” wave?
• is there a “p” wave for every QRS?
  
  • do the p’s walkout? are they regular?
  • do the QRS’s walkout? are they regular?
• what is the ventricular rate? (how many QRS’s times 10)
• measure PR interval. Is it normal? (less than 0.2 seconds)

Question 6

what is this rhythm?

Answer 6

• normal sinus rhythm
  
  • has P’s, QRS’s, and a P for every QRS
    
    • the P’s and the QRS’s walk out
    • rate is normal
• sinus node fires 60-100 bpm (or 50-90 bpm in some sources)
• follows normal conduction pattern

Question 7

what is this rhythm?

Answer 7

• sinus bradycardia:
  
  • has P’s, has QRS’s, has a P for every QRS
  • P’s and QRS’s walk out
  • rate is slow
• sinus node fires at a rate <60 bpm
• normal rhythm in aerobically trained athletes and during sleep
• only need to treat if symptomatic w/ weakness, syncope, low HR/BP
  
  • tx: atropine, pacemaker

Question 8

what is this rhythm?

Answer 8

• sinus tachycardia:
  
  • has P’s, has QRS’s, has a P for every QRS
  • P’s and QRS’s walk out
  • rate is fast
• discharge rate from sinus node is increased and is >100 bpm
• could be normal if currently active, in pain, has anxiety
  
  • tx: treat underlying problem, use vagal maneuvers
• if HR gets too high: can use adenosine, beta blockers, CCBs

Question 9

what is this rhythm?

Answer 9

• atrial fibrillation
  
  • has QRS’s, but has NO P WAVES!
  • QRS’s DO NOT walk out, they are irregular
  • ventricular rate can be WNL
    
    • but atrial rate can be as high as 350-400
• patho: total disorganization of atria b/c P wave is where electrical impulse starts (at SA node), so in this case, the atria are sending impulses at lots of irregular times
  
  • pt has no atrial kick, so b/c no oomph from atria to get ventricles contracting, the ejection fraction is low
• tx:
  
  • control HR w/ digoxin
  • warfarin to prevent DVT long term
  • amiodarone use to convert pt back to normal sinus

Question 10

what is this rhythm?

Answer 10

• atrial flutter:
  
  • has QRS’s
  • QRS’s walk out (but sometimes they don’t)
  • sawtooth pattern
• patho: atria are being more consistent, but ventricle not contracting for every atrial signal
  
  • usually caused by something else such as an MI, pneumonia, ascites
• tx is the same as a fib, but this is more episodic and you don’t usually live with this, b/c when fix underlying dz process, then flip back to sinus rhythm
  
  • tx:
    
    • digoxin: to slow HR
    • warfarin: DVT prophylaxis
    • amiodarone: to convert back to normal sinus

Question 11

what is this rhythm?

Answer 11

• sinus tachycardia with premature atrial contractions (PACs)
  
  • PAC: just a beat
  • QRS’s and P’s are present
    
    • P wave for every QRS
    • P’s and QRS’s DO NOT walk out
    • rate can be WNL
• atria contracts prematurely, so shows as a P wave, then ventricles contract and QRS happens, then returns to normal rhythm
• caused by caffeine, alcohol, tobacco, fatigue, stress, electrolyte imbalances
• tx: tx underlying cause (ie remove caffeine)

Question 12

what is this rhythm?

Answer 12

sinus bradycardia w/ multifocal PVCs

Question 13

what is this rhythm?

Answer 13

normal sinus rhythm with unifocal PVCs

Question 14

what is this rhythm?

Answer 14

• normal sinus rhythm with bigeminal PVCs
  
  • bigeminal means every other beat is a PVC

Question 15

what is this rhythm?

Answer 15

• normal sinus rhythm with triplet PVCs
  
  • triplet: 3 PVCs in a row
    
    • look like v tach b/c not getting the cardiac output
  • couplet: another variation which means 2 PVCs in a row

Question 16

premature ventricular contractions (PVCs)

Answer 16

• contraction originating in ectopic focus of the ventricles
• premature occurrence of a wide and distorted QRS complex
  
  • no P wave before a large, wacky QRS
• cardiac output is decreased from what is should be b/c don’t leave time for ventricles to fill
  
  • especially if couplet/triplet
• the more diseased the heart is, the greater likelihood of PVCs
• tx: tx the cause
  
  • amiodarone
  • lidocaine

Question 17

pacemaker

Answer 17

• used to pace heart when the normal conduction pathway is damaged or diseased
• mostly used when pt has severe, symptomatic bradycardia
• if pt has a pacemaker ventricular wire: pacer spike before QRS
• if pt has a pacemaker atrial wire: pacer spike before P wave

Question 18

implantable cardioverter defibrillator (ICD)

Answer 18

• this is a pacemaker that is also able to shock the patient if they go into v tach or v fib
  
  • all ICDs have pacemakers, but not all pacemakers have ICDs
  • will not shock pt in asystole
• via subclavian vein to endocardium

Question 19

what is this rhythm?

Answer 19

• first degree AV block
  
  • P’s and QRS’s present
    
    • P for every QRS
    • P and QRS walk out
    • PR is prolonged more than 0.2 seconds or 5 little blocks
• cause: check medications b/c medications like beta blockers can cause this by prolonging the PR interval and slowing the HR
• tx: continue to monitor if asymptomatic

Question 20

ventricular tachycardia

Answer 20

• run of 3-4 PVCs, no p waves
• can be stable or unstable, sustained or unsustained
  
  • sustained: stay in v tach
  • unsustained: go in and out of v tach
• considered life threatening: b/c of decreased cardiac output and the possibility of deterioration into v fib
• if pt has a pulse, tx like tachycardia, but quickly b/c pt can go into v tach w/o a pulse or v fib
  
  • so give adenosine or IVP beta blocker
• if pt is w/o a pulse, start CPR and call a code

Question 21

what is this rhythm?

Answer 21

ventricular tachycardia

Question 22

what is this rhythm?

Answer 22

• ventricular fibrillation
  
  • no pulse, no cardiac output
• tx: CPR with defibrillation

Question 23

what is this rhythm?

Answer 23

• asystole
  
  • represents total absence of ventricular electrical activity
  • no ventricular contraction, so no cardiac output, occurring b/c depolarization does not occur
• tx: check pt, and if no response from pt, start CPR
  
  • should not shock this rhythm until some type of electrical activity

Question 24

pulseless electrical activity (PEA)

Answer 24

• looks like normal sinus rhythm
  
  • QRS and P are present
  • everything walks out
  • there is a P for every QRS
    
    • pt does not have a pulse, but the only way to tell is through assessment!
• electrical system is working, but the heart is not contracting, so there is no pulse and no cardiac output!
  
  • occurs most often in a very diseased heart
• most common thing that triggers PEA is a change in rate (like 80 to 40)
• will eventually become asystole, so immediately call code and start CPR

Question 25

what to do if you see STEMI on a 12 lead EKG?

Answer 25

* immediately put O2 on patient and draw troponins and CK-MB