When measuring the height of peaks in an EKG, what does each large square represent?

In an EKG, each large square on the grid represents a measurement of 5mm x 5mm. This standard measurement is key for calculating the amplitude of different waveforms such as P waves, QRS complexes, and T waves. In terms of voltage, each large square corresponds to 0.5 mV; therefore, when counting the number of large squares that a peak reaches above the baseline, it provides a quick and effective way to quantify the height of that peak in millivolts.

This information is crucial for interpreting various heart conditions, as changes in the amplitude of these waves can indicate abnormalities in heart function. Understanding and using the standard measurement of large squares ensures accuracy when assessing EKG tracings and diagnosing possible cardiac issues.