ESTIMATE FROM EKG TRACING
Count Complexes in a 6 second strip
Multiply complex count by 10
Interval between complexes
Count large boxes (0.2 seconds) between complexes
Divide 300 by box count: 300, 150, 100, 75, 60, 50
INTERVAL BETWEEN COMPLEXES
Count large boxes (0.2 seconds) between complexes
DIVIDE 300 BY BOX COUNT: 300, 150, 100, 75, 60, 50
1 large box (200 ms or 0.2 seconds): 300 bpm
2 large boxes (400 ms or 0.4 seconds): 150 bpm
3 large box (600 ms or 0.6 seconds): 100 bpm
4 large boxes (800 ms or 0.8 seconds): 75 bpm
5 large box (1000 ms or 1.0 seconds): 60 bpm
6 large boxes (1200 ms or 1.2 seconds): 50 bpm
7 large box (1400 ms or 1.4 seconds): 43 bpm
8 large boxes (1600 ms or 1.6 seconds): 37 bpm
WAYS TO DETERMINE RATE
1. By going by the big squares..memorise this sequence:300,150,100,75,50
2. Count the number of big squares between 2 consecutive R waves...then divide 300 by that number.
3. If the rhythm is irregular, get a 6 second strip (15 big squares=3 sec), count the number of P waves for atrial rate, or R waves for ventricular rate, multiply by 10.
4. One method is to divide 1500 by the number of small squares between two R waves.
