The Nurse Needs to Quickly Estimate the Heart Rate for a Patient

The nurse needs to quickly estimate the heart rate for a patient with a regular heart rhythm.Which method will be best to use?

A) Count the number of large squares in the R-R interval and divide by 300.
B) Print a 1-minute electrocardiogram (ECG) strip and count the number of QRS complexes.
C) Calculate the number of small squares between one QRS complex and the next and divide into 1500.
D) Use the 3-second markers to count the number of QRS complexes in 6 seconds and multiply by 10.