Finding and Understanding a Normal Pulse Rate

Many factors help practitioners choose where to feel for the pulse and determine a patient's pulse rate. These include age, body type, and the clinical situation. For example, doctors will assess the pulse in one location during CPR and another during a routine medical exam. In some cases, comparing bilateral pulses — those in the upper and lower extremities — is also helpful.

There are two peripheral pulses in the upper extremities. The radial pulse is located in the wrist, at the base of the thumb. It is commonly assessed during routine exams of adults because it is easy to access. The brachial pulse runs along the inner elbow and is the location of choice when assessing the heart rate during infant CPR.

The pulses used to assess abnormal or normal pulse rate in the lower extremities are the femoral pulse at the upper inside part of the leg, the popliteal pulse behind the knee, and the pedal pulse on the top of the foot. The femoral pulse is the most sensitive to changes in septic shock and is commonly assessed during resuscitation.

Normal pulse rate is also assessed at the carotid pulse, found on either side of the neck. The carotid arteries carry oxygenated blood from the heart to the brain; they are palpated on either side of the front of the neck, just under the jawline. This is the primary location for assessing the pulse when performing CPR on an adult.

The apical pulse lies on the left side of the chest, between the fifth and sixth rib. This is where the apex of the heart sits and the point of maximal impulse. Listening to the apical pulse with a stethoscope is an effective way to assess the heart, but examining the peripheral pulses is very useful, too. Listening to the carotid or femoral pulse can reveal partial obstruction of the nearby vessels.

What is considered a "normal" pulse rate greatly depends on age. For adults at rest, a heart rate between 60 and 100 is normal. Infant and child rates vary drastically by age. Infants typically have a pulse between 100 and 170 when awake. For toddlers, 80 to 150 is normal; preschoolers, 70 to 130; school-aged children, 65 to 120; and teenagers, 55 to 90.

Multiple factors affect a person's normal pulse rate. The heart pumps more blood when the temperature and humidity are high, increasing heart rate by five to 10 beats per minute. Stress and anxiety raise the normal pulse rate as well, and it rises a bit when going from lying or sitting to standing but quickly returns to baseline. Certain heart medications also lower the pulse.

Bradycardia is an abnormal heart rate that is slower than the normal pulse rate, typically less than 60 beats per minute. Someone experiencing bradycardia may feel weak or dizzy. A lot of things can cause this event. Some are serious, like heart conditions and drug reactions. On the other hand, people who exercise regularly may have a normal pulse rate of less than 60.

Tachycardia is a higher-than-normal pulse rate. Serious arrhythmias, like ventricular fibrillation, are life-threatening and can require a shock from a defibrillator or a pacemaker to maintain a regular rhythm. Some causes of tachycardia are less serious but still require attention, including dehydration, fever, stress, fear, exercise, overactive thyroid, and anemia.

One of the most important times to pay attention to pulse is during exercise. The body gets the most benefits from exercise when the pulse is in the "target heart rate zone", which is 60 to 80 percent of the individual's maximum heart rate. When the heart rate gets too high during exercise, the risk of injury increases. The best way to find out a target heart rate is to ask your doctor. When exercising, stop periodically to check a 10-second pulse. If it's too low, increase the intensity of the exercise. If it's too high, decrease the intensity of activity to bring it down into the target zone.