What is a normal blood pressure for an infant

Overview

In many respects, children aren’t “little adults.” This is true when it comes to vital signs. Vital signs, or vitals for short, are a measurement of:

• blood pressure
• heart rate (pulse)
• respiratory rate
• temperature

This important information can tell a medical provider a lot about a child’s overall health.

Normal values for vital signs exist for adults, but are often different for children, depending on their age. When you take your little one to the doctor’s office, you may notice that some vital signs are lower than an adult’s, while others are higher. Here’s what to expect when it comes to vital signs and your child.

Infants have a much higher heart and respiratory (breathing) rate than adults do. An infant’s muscles aren’t highly developed yet. This is true for the heart muscle and the muscles that assist breathing.

Think of the heart muscles like a rubber band. The further you stretch a rubber band, the harder and more forcefully it “snaps” back into place. If an infant’s heart cannot stretch very much due to immature muscle fibers, it has to pump at a faster rate to maintain blood flow through the body. As a result, an infant’s heart rate is often faster. It can also be irregular.

When an infant gets older, the heart muscle can stretch and contract more effectively. This means the heart doesn’t have to beat as fast to move blood through the body.

If an infant’s heart rate is lower than normal, it’s often cause for concern. Potential causes of slow heart rate, also known as bradycardia, in infants include:

• not enough oxygen
• low body temperature
• medication effects
• a congenital heart problem

While there can be variations, given a child’s overall condition, the average vital signs for an infant are:

• heart rate (newborn to 1 month): 85 to 190 when awake
• heart rate (1 month to 1 year): 90 to 180 when awake
• respiratory rate: 30 to 60 times per minute
• temperature: 98.6 degrees Fahrenheit

Forblood pressure:

• neonate (96 hours old to 1 month): 67 to 84 systolic blood pressure (top number) over 31 to 45 diastolic (bottom number)
• infant (1 to 12 months): 72 to 104 systolic over 37 to 56 diastolic

After a child turns 1, their vital signs progress more toward adult values. From age 1 to 2, they should be:

• heart rate: 98 to 140 beats per minute
• respiratory rate: 22 to 37 breaths per minute
• blood pressure: systolic 86 to 106, diastolic 42 to 63
• temperature: 98.6 degrees Fahrenheit

When a child is 3 to 5 years old, their average vital signs are:

• heart rate: 80 to 120 beats per minute
• respiratory rate: 20 to 28 breaths per minutes
• blood pressure: systolic 89 to 112, diastolic 46 to 72
• temperature: 98.6 degrees Fahrenheit

The average vital signs of a child who is 6 to 11 years old are:

• heart rate: 75 to 118 beats per minute
• respiratory rate: 18 to 25 breaths per minute
• blood pressure: systolic 97 to 120, diastolic 57 to 80
• temperature: 98.6 degrees Fahrenheit

Adolescent vital signs are essentially the same as those of an adult. By this time, heart and breathing muscles have developed to near-adult levels:

• heart rate: 60 to 100 beats per minute
• respiratory rate: 12 to 20 breaths per minutes
• blood pressure: systolic 110 to 131, diastolic 64 to 83
• temperature: 98.6 degrees Fahrenheit

Whether child or adult, the average body temperature is about 98.6 degrees Fahrenheit. However, a person’s temperature can go up and down throughout the day. Hormone swings, exercise, taking a bath, or being exposed to hot or cold weather can all affect a child’s temperature.

You can take your child’s temperature in a number of areas (provided they are still young enough to let you). Each area of the body can have different values for what constitutes a fever. According to Sutter Health/California Pacific Medical Center, the following values indicate fever in your child:

• axillary: greater than 99 degrees Fahrenheit (37.2 degrees Celsius)
• ear (tympanic): greater than 99.5 degrees Fahrenheit and 37.5 degrees Celsius if on oral mode (note that doctors don’t recommend taking an ear temperature on children younger than 6 months old)
• oral: greater than 99.5 degrees Fahrenheit (37.5 degrees Celsius)
• pacifier: greater than 99.5 degrees Fahrenheit (37.5 degrees Celsius)
• rectal: greater than 100.4 degrees Fahrenheit (38 degrees Celsius)

While having a fever is not a fun occurrence for your child, it has protective effects and can indicate that the body’s immune system is trying to fight off the infection. However, you should always call your child’s doctor if the child is younger than 3 months old and has a fever. For children older than 3 months, call your child’s pediatrician if they have a fever greater than 104 degrees Fahrenheit.

While adults commonly experience high blood pressures due to a buildup of cholesterol in their bodies (called atherosclerosis), children don’t have the same contributing factors. So when their blood pressure is either too high or too low, a doctor is often concerned.

Usually the younger a child is, the more concerned a doctor is by high or low blood pressure. Blood pressure can indicate a heart or lung defect in very young children. Examples of potential causes of high blood pressure in infants include:

• bronchopulmonary dysplasia
• coarctation of the aorta
• kidney abnormalities, such as renal artery stenosis
• Wilms tumor

When a child is school-aged, hypertension is most likely due to being overweight, according to KidsHealth.

Hypotension, or too-low blood pressure, is pressure that is 20 mmHg lower than a child’s average blood pressure. Common causes of hypotension include blood loss, sepsis (severe infection), or a severe allergic reaction. Children with these conditions usually appear quite sick. Blood pressure below the listed averages in an otherwise well-appearing child is often normal.

Remember that heart rate, respiratory rate, and blood pressure are all closely linked. The heart pumps blood throughout the body to ensure the blood can flow by the lungs to get oxygen and then take the oxygenated blood to the tissues. If a person doesn’t get enough oxygen, their heart rate and respiratory rate will speed up in an attempt to get more oxygen.

If you take your child’s vital signs and they deviate significantly from the norms, you may need to call your child’s doctor. Here’s what to check for:

• You can count a child’s respirations by putting your hand on your child’s chest and feeling how often the chest rises and falls.
• You can measure a child’s heart rate by feeling their brachial pulse, which is the pulse inside the crook or bend of the arm on your child’s “pinky finger” side of the arm.
• Blood pressure can be checked using an automatic blood pressure cuff or a manual cuff (known as a sphygmomanometer) and stethoscope. Note, however, that the size of the blood pressure cuff can affect the reading. An adult-sized cuff will often give an incorrect reading when used on a child.

Of course, you should get the above checked at your pediatrician’s office. If your child appears active and otherwise well, an abnormal vital sign is likely not a medical emergency, but warrants a phone call or office visit. If your child seems at all sick, be sure to get them emergency medical care right away.

If your child doesn’t appear ill but became agitated before or while you measured vital signs, you may wish to try to measure them again when they are less upset. This can usually yield more accurate results.

Remember that vital signs are an important part of the overall picture, but it’s important to consider your child’s behavior as well.

Ask yourself these questions:

Taking these factors into account can also let you know if your child’s vital signs are cause for concern.