Vital signs
Vital signs reflect essential body functions, including your heartbeat, breathing rate, temperature, and blood pressure. Your health care provider may watch, measure, or monitor your vital signs to check your level of physical functioning.
Normal vital signs change with age, sex, weight, exercise capability, and overall health.
Normal vital sign ranges for the average healthy adult while resting are:
- Blood pressure: 90/60 mm Hg to 120/80 mm Hg
- Breathing: 12 to 18 breaths per minute
- Pulse: 60 to 100 beats per minute
- Temperature: 97.8°F to 99.1°F (36.5°C to 37.3°C); average 98.6°F (37°C)
To measure the pulse at the wrist, place the index and middle finger over the underside of the opposite wrist, below the base of the thumb. Press firmly with flat fingers until you feel the pulse in the radial artery.
To measure blood pressure, your doctor uses an instrument call a sphygmomanometer, which is more often referred to as a blood pressure cuff. The cuff is wrapped around your upper arm and inflated to stop the flow of blood in your artery. As the cuff is slowly deflated, your doctor uses a stethoscope to listen to the blood pumping through the artery. These pumping sounds register on a gauge attached to the cuff. The first pumping sound your doctor hears is recorded as the systolic pressure, and the last sound is the diastolic pressure.
Fever is an important part of the body's defense against infection. Most bacteria and viruses that cause infections in humans thrive best at 98.6 degrees F (37 degrees C). Raising the body temperature a few degrees can help the body fight the infection. In addition, a fever activates the body's immune system to make more white blood cells, antibodies, and other infection-fighting agents.
References
Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW. Vital signs and pain assessment. In: Ball JW, Dains JE, Flynn JA, Solomon BS, Stewart RW, eds. Seidel's Guide to Physical Examination. 9th ed. St Louis, MO: Elsevier; 2019:chap 6.
Simel DL. Approach to the patient: history and physical examination. In: Goldman L, Schafer AI, eds. Goldman-Cecil Medicine. 26th ed. Philadelphia, PA: Elsevier; 2020:chap 6.
Version Info
Last reviewed on: 1/16/2021
Reviewed by: Linda J. Vorvick, MD, Clinical Associate Professor, Department of Family Medicine, UW Medicine, School of Medicine, University of Washington, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.
