These measurements are taken to help assess the general physical health of a person, give clues to possible diseases, and show progress toward recovery.

[1][2] The normal ranges for a person's vital signs vary with age, weight, sex, and overall health.

This was done in recognition that deteriorating vital signs often precede cardiac arrest and/or admission to the intensive care unit.

Used appropriately, a rapid response team can assess and treat a deteriorating patient and prevent adverse outcomes.

[4][5][6] There are four primary vital signs which are standard in most medical settings:[7] The equipment needed is a thermometer, a sphygmomanometer, and a watch.

[13] The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever.

A fever of 38 °C does not necessarily indicate an ominous sign if the patient's previous temperature has been higher.

In addition to providing the heart rate, the pulse should also be evaluated for strength and obvious rhythm abnormalities.

The pulse may vary due to exercise, fitness level, disease, emotions, and medications.

Respiratory rate is a clear indicator of acidotic states, as the main function of respiration is removal of CO2 leaving bicarbonate base in circulation.

Therefore, elevated blood pressure (hypertension) is variously defined when the systolic number is persistently over 140–160 mmHg.

In the U.S., in addition to the above four, many providers are required or encouraged by government technology-in-medicine laws to record the patient's height, weight, and body mass index.

While monitoring has traditionally been done by nurses and doctors, a number of companies are developing devices that can be used by consumers themselves.