EKGs - counting whole vs half boxes


Hi all! This is my 3rd week on an orthopedic floor (did LPN to RN transition) and had a slight confusion when talking to a nurse manager. The floor just received tele and none of the floor nurses knew how to interpret EKGs and asked for my help. As an LPN and refresher in RN courses, I have always been taught to count the "half boxes," and to be as precise as possible. As I was showing the floor nurses, the nurse manager busted out of her office and immediately told everyone never to count half boxes, always round up. Even in orientation the ICU nurse taught half boxes...I just don't like "guesstimating" what my pts ekg measurements are. Even thought the answers are only slightly different, she seemed very offended to tell anyone to count half boxes...

any insight?


blondy2061h, MSN, RN

1 Article; 4,094 Posts

Specializes in Oncology. Has 15 years experience.

I'm not sure what you mean by half boxes, I guess. There's the big boxes that are 0.2 seconds, and the small boxes that are 0.04 seconds. I plot out what I'm measuring on scrap paper or with calibers and line it up with the boxes. I've never felt the need to go smaller than the 0.04 boxes. If you're being scientific about it, you can only measure as accurately as your tool allows you to. So yes, you should be using the nearest box.

Now I use the digital calibers on the cardiac monitor and it does the measuring from there.


5 Posts

Sorry, I should have specified! I am talking about the 0.04 boxes. I have always counted as precise as possible (0.02), and she told me to round up to 0.04 every time.