Heart rate (HR): measure of the frequency of cardiac cycles; expressed in beats per minute (BPM)
Determining Heart Rate
3-step approach:
- (1) Locate R wave that falls on or near thick line
- (2) Count # of thick lines until next R wave
- (3) Use “300-150-100-75-60-50” rule
Regular rhythms:
- If HR <100 BPM HR = (300) / (# large squares b/t cycles)
- If HR >100 BPM HR = (1500) / (# small square b/t cycles)
Irregular or bradycardic rhythms:
- HR = (# cycles over interval) x (# to get to 1 minute)
- Example:
- If 18 cycles occur over 6-second interval
- And, (6 seconds) x (10) = 60 seconds = 1 minute
- Then, HR = (22 cycles) x (18) = 108 BPM