The heart rate is one of your body's vital signs, indicating its level of functioning. A normal heart rate varies, depending on your age and circumstances. Newborn babies have faster heart rates than adults, and various factors, such as heart conditions, physical activity or physical fitness, can influence heart rate. A child who is 15 months old has a heart rate that is slower than a newborn baby but still faster than that of an adult.
A heart rate measures how many times the heart beats over the course of a minute. Each beat that occurs when checking a pulse represents the contraction of the heart muscle as it pushes blood into the circulatory system. According to the nursing continuing education website RNCeus.com, the normal range of heart rate for a child of 15 months is between 80 and 130 beats per minute.
An arrhythmia occurs -- just as the name implies -- when the heart does not beat in a normal or expected rhythm. One very common arrhythmia, known as "sinus arrhythmia" occurs in children and is completely normal and harmless. In sinus arrhythmia, the heart rate speeds up a bit when the child breathes in and slows down again when the child breathes out. Other arrhythmias indicate the need for further testing and possible treatment. A doctor can determine whether your child has a heart arrhythmia and will do additional tests if needed.
Tachycardia occurs when the heart beats faster than a normal rate. A child who is 15 months old and has a heart rate greater than 130 beats per minute can be considered to have tachycardia. This situation is typically temporary -- a child's heart rate can increase above normal due to situations such as stress, crying or high levels of activity. Following the episode, the heart rate should return to normal limits. Bradycardia occurs when the heart beats at a slower pace than normal, such as when a 15-month-old is sleeping and her heart rate drops below 80. Your doctor can tell you if your child's heart rate is too fast or too slow for her age and circumstances.
You can check the heart rate of your 15-month-old child by taking a pulse. Place two fingers in the inside of her upper arm, between the elbow and the shoulder. Once you feel a heartbeat with your fingers count for 60 seconds, and this is the child's heart rate. Avoid using your thumb to check for a heartbeat, as the thumb has a pulse of its own and this may give you an incorrect figure. Contact your doctor if your child's heart rate seems unusually fast, slow or irregular, or if she is having symptoms of weakness, shortness of breath or discoloration around the lips and nailbeds.