Vital signs

One way to keep tabs on your family's health is to understand what vital signs mean. So how do you know what's normal? The information here can help because it provides normal and, in certain instances, optimal parameters for blood pressure, pulse rate, temperature and respiration at different ages. Keep in mind these are guidelines. What may be average vital signs for you aren't necessarily average for your best friend. If you have any concerns about specific vital signs, contact your health care provider.


Blood pressure norms
Blood pressure is a measurement of the amount of force that blood exerts on the arteries (blood vessels that carry blood from the heart to the rest of the body) as it's pumped from the heart through the circulatory system. When you have your blood pressure taken, there are two different measurements: systolic and diastolic. Systolic (the top number in a blood pressure reading) measures the highest pressure within your arteries when the heart squeezes or pumps. Diastolic (the bottom number in a blood pressure reading) indicates the pressure in your arteries when the heart is at rest.
Blood pressure norms in children vary with gender, age and height. Rather than an absolute numeric cutoff, high blood pressure in children is defined as average systolic and diastolic blood pressure greater than or equal to the 95th percentile for age and sex. High-normal blood pressure is blood pressure greater than or equal to the 90th percentile, but less than the 95th percentile. The following numbers will give you an idea of what the National Institutes of Health (NIH) considers the upper limit of normal blood pressure for a child with average height (50th percentile) as determined by growth curves:


Age Systolic Diastolic
1 year 98 (boy)
100 (girl) 53 (boy)
54 (girl)
5 years 108 (boy)
106 (girl) 67 (boy)
67 (girl)
10 years 115 (boy)
115 (girl) 75 (boy)
74 (girl)
15 years 127 (boy)
124 (girl) 79 (boy)
79 (girl)

For adults, the following blood pressure numbers are listed as cutoffs for normal, prehypertension and hypertension:


Category Systolic Diastolic
Normal Less than 120 Less than 80
Prehypertension 120 to 139 80 to 89
Hypertension Greater than or equal to 140 Greater than or equal to 90

Note: Normal refers to the best blood pressure to reduce the risk of heart attack, stroke and other major complications related to blood pressure. Also, unusually low blood pressure readings warrant evaluation by a doctor to determine the clinical significance, if any, especially if low blood pressure situations are associated with symptoms.


Temperature
Body temperature normally varies according to time of day and place of measurement. In fact, it can vary as much as .9°F (.5°C) during the day in a healthy person. A normal oral temperature (a temperature taken by mouth) is 98.6°F (37°C). A normal rectal temperature is 99.5°F, and a normal armpit temperature is 98.1°F. A fever is defined as an oral temperature over 99.5°F (37.5°C), a rectal temperature over 100.4°F (38.0°C), or an armpit temperature over 99.0°F (37.2°C).
To convert a temperature from Fahrenheit to Celsius, subtract 32 from the Fahrenheit reading and multiply by 5/9. Or, subtract 32 from the Fahrenheit reading and divide by 1.8.

To convert a temperature from Celsius to Fahrenheit, multiply the Celsius reading by 9/5 and add 32. Or, multiply the Celsius reading by 1.8 and add 32.


Pulse rate
Pulse rate is a measurement of the number of times your heart beats in one minute. To count your pulse, place two fingers lightly underneath your jaw line on the side of your neck and count the number of beats you feel in one minute. While you're exercising, it may be more accurate to count the number of beats you feel in 10 seconds and multiply by six. It's important to remember that pulse rate varies according to your activity level and a variety of other factors. For example, exercise, fever and stress elevate your pulse rate in response to your body's increased need for oxygen and nutrients.
Average pulse rates for children vary by age, but remain higher until ages 6 to 8.

Age Beats per minute
birth to 11 months Average rates vary by age in weeks to age in months.
11 months to 2 years 80 to 160
2 to 4 years 80 to 130
4 to 6 years 80 to 120
6 to 8 years 75 to 115
8 years to adolescence 70 to 110
adolescence to adulthood (13 to 18 years) 60 to 110


The normal adult pulse range is 60 to 80 beats per minute, though up to 100 beats per minute is still within the average range. Well-conditioned athletes have a slower pulse range, often 40 to 60 beats per minute.


Respiration
Respiration is the process of inhaling and exhaling air. It's counted by the number of breaths in one minute. Like pulse rates, respiration rates can increase from factors such as exercise, stress and fever.
Average respiration rates for children vary by age.


Age Breaths per minute
birth to 1 year 30 to 39
1 to 2 years 26 to 31
2 to 6 years 21 to 29
6 to 9 years 20 to 24
9 to 13 years 19 to 22
13 to 15 years 18 to 21
15 to 18 years 16 to 21

The normal adult respiration rate is 12 to 20 breaths per minute.