Rate & Rhythm
What is the normal heart rate for normal sinus rhythm.
60-100 bpm
What part of the ECG represents atrial depolarization?
P Wave
How many seconds is a small box on ECG paper?
0.04 seconds
Regular, narrow QRS, sawtooth P waves
Atrial flutter
A patient suddenly becomes unresponsive, and you see VFib on the monitor. What's the priority?
Start CPR and defibrillate immediately
This rhythm has a regular rate, upright P waves before every QRS, and normal intervals.
Normal Sinus Rhythm
What is the normal duration of the QRS complex?
<0.12 seconds
How many large boxes equal one second?
5 large boxes
Irregular rhythm, no P waves, chaotic baseline
Atrial Fibrillation
Peaked T waves may indicate?
Hyperkalemia
This rhythm has a rate <60 bpm but otherwise normal characteristics.
Sinus Bradycardia
Which part of the ECG represents ventricular depolarization?
QRS Complex
What is the normal PR interval range?
0.12–0.20 seconds
No electrical activity
Asystole
Can you shock asystole?
No
The PR interval is consistently prolonged >0.20 sec but every P wave is followed by a QRS.
1st Degree AV Block
What is the significance of ST elevation?
It may indicate myocardial injury or infarction
What part of the ECG do you use to calculate heart rate quickly?
The R-R interval
Regular rhythm, PR interval progressively lengthens until a beat is dropped
2nd Degree AV Block, Mobitz I (Wenckebach)
You patient is in SVT - what medication do you give?
Adenosine
No relationship between P waves and QRS complexes.
3rd Degree AV Block
What does the R-R interval help determine?
Heart rate and rhythm regularity
What is the normal QRS duration?
Up to 0.12
Chaotic, irregular waveform, no identifiable QRS or P waves, no pulse
Ventricular Fibrillation
How do you treat Torsades de Pointes?
Magnesium