0.12-0.2
PR interval
How many small boxes is the PR interval?
3-5
depolarization of the atria
PR interval
0.04-0.12
QRS interval
How many small boxes is the QRS?
1-3
ventricular depolarization
QRS
Time it takes for de and repolarization of ventricles to occur
QT interval
HR 150-220
regular or irregular
Paroxysmal Supraventricular Tachycardia
-Comes from above the bifurcation of the bundle of His
paroxysmal supraventricular tachycardia
What are the s/s and tx of paroxysmal supraventricular tachycardia?
- hypotension, duspnea, angina
- vagal stimulation, valsalva, cough, IV adenosine
- early occurence of the QRS complex
- wide distorted shape
- contraction of the ventricles outside the normal pattern
PVC
What is the cause of a PVC?
-stress, stimulants, MI, HF, cardiomyopathy, hypokalemia
- no P wave
- QRS is wide and distorted
ventricular tachycardia
What is the cause of ventricular tachycardia?
MI, CAD, electrolyte imbalance, MVP, drug toxicity
- extremely irregular
- absent P wave
- HR: 300-600
V-fib
- the heart is quivering and not beating
- can cause sudden cardiac arrest
V-fib
What is the treatment for v-fib?
defib
CPR
determine cause
begin ACLS
- irregular with a narrow QRS
- P wave is fine to coarse
A-fib
- PR interval >.20
- QRS >.12
-first degree AV block
-PR interval gets progressively longer until it completely blocks a QRS complex
2nd degree AV block type 1
- PR intervals are constant
- more P waves than QRS complexes
- P waves are regular
2nd degree AV block type 2
- no communication between atria and ventricles
- atria are firing irregularly and communication to ventricles is blocked
- P wave is normal but not related to QRS
- no relationship between P and RS
3rd degree block
