Vital Signs: Heart Rate

The second vital sign to be discussed in this series is heart rate, sometimes referred to as pulse rate or just pulse. This variable gives a rough idea of a patient´s cardiac status. It is simply a measure of the number of heart beats per minute. The simplest way to measure heart rate is to palpate (feel) an individual´s pulse by placing a finger over an artery located close to the body surface, such as the radial artery in the wrist, and counting the number of pulsations felt over a minute´s time. Thus, the only instrumentation that is really needed to measure this vital sign is a finger and a clock. Heart rate and breathing rate are, therefore, the easiest of the four vital signs to measure, and these variables can be determined without any electronic instrumentation; yet, there are applications where having electronic methods to measure this vital sign can be very useful and can provide information that is not readily available from palpating and counting the pulse. This paper presents various electronic instruments to determine the heart rate.