Calculating Heart Rate || Triplicate Method in EMS
Fall is upon us! 🍁 For most this just means cooler weather and pumpkin spice drinks ☕️, but for first semester medic students this could mean intro to EKGs 🫀…..and possibly the end of their social life for awhile! 😆 All jokes…..kind of. 😏
Expanding cardiology knowledge and skills is one of the most intimidating, but rewarding parts of paramedic school. You’re bound to have that epiphany moment where you start to realize what the squiggly lines (or lack there of) actually mean!
As you are being introduced to EKGs, you will be taught multiple methods of how to calculate a heart rate on a strip. Let’s talk about what the strip/EKG actually consists of.
Ever noticed that a strip is made up of multiple little boxes▪️?Each of those boxes represent time. The smallest boxes represents 0.04 seconds and 25 of those small boxes make up a “Big Box.” When we are looking at a 6 second strip, there should be a total of 30 big boxes.
Today I’m going to review only one of the methods of calculating the heart rate. Whether we refer to it as the big box method or the triplicate method, it is only to be used for regular rhythms above 50 bpm. The R to R interval has to march out equally. Now how do we do this? Please refer to the photo as a visual representation of the following explanation.
- Take your EKG (make sure the rhythm is regular and over 50 bpm)
- Find a QRS complex that lands on one of the dark lines at the beginning or end of a big box.
- Starting with that line we will go to the next dark line and that will be 300, repeat this and next will be 150, etc.
- The sequence will go 300, 150, 100, 75, 60, 50
This method is a life saver in a pinch! I will be introducing some of the other methods soon.
🚨 Disclaimer: This is not meant to be used as or in the place of professional medical advice. Remember to abide by your local protocol & stay within your scope of practice. 🚨
Expanding cardiology knowledge and skills is one of the most intimidating, but rewarding parts of paramedic school. You’re bound to have that epiphany moment where you start to realize what the squiggly lines (or lack there of) actually mean!
As you are being introduced to EKGs, you will be taught multiple methods of how to calculate a heart rate on a strip. Let’s talk about what the strip/EKG actually consists of.
Ever noticed that a strip is made up of multiple little boxes▪️?Each of those boxes represent time. The smallest boxes represents 0.04 seconds and 25 of those small boxes make up a “Big Box.” When we are looking at a 6 second strip, there should be a total of 30 big boxes.
Today I’m going to review only one of the methods of calculating the heart rate. Whether we refer to it as the big box method or the triplicate method, it is only to be used for regular rhythms above 50 bpm. The R to R interval has to march out equally. Now how do we do this? Please refer to the photo as a visual representation of the following explanation.
- Take your EKG (make sure the rhythm is regular and over 50 bpm)
- Find a QRS complex that lands on one of the dark lines at the beginning or end of a big box.
- Starting with that line we will go to the next dark line and that will be 300, repeat this and next will be 150, etc.
- The sequence will go 300, 150, 100, 75, 60, 50
This method is a life saver in a pinch! I will be introducing some of the other methods soon.
🚨 Disclaimer: This is not meant to be used as or in the place of professional medical advice. Remember to abide by your local protocol & stay within your scope of practice. 🚨