VITAL SIGNS: What do the numbers mean?

Vital signs are measurements of body’s basic functions.

The four main vital signs routinely monitored by medical professionals and health care providers include the following: body temperature(BT or T), blood pressure(BP), pulse/heart rate(HR), and respiratory rate/breathing rate(RR). These measurements are taken to help asses the general physical health of a person, give clues to possible diseases, and show progress toward recovery.

Your primary health care provider may watch, measure, or monitor your vital signs to check your level of physical functioning.

Normal vital signs change with age, gender, weight, exercise capability, and overall health.

Body temperature

The normal body temperature of a person varies depending on gender, recent activity, food and fluid consumption, time of day, and, in women, the stage of the menstrual cycle. Normal body temperature can range from 36.5C to 37.2C for a healthy adult.

Body temperature can be taken:

Orally: using either the classic glass thermometer or digital thermometers

Rectally: temperatures taken rectally tend to be slightly higher than taken orally.

Axillary: temperatures can be taken under the arm using a glass or digital thermometer. Axillary reading tend to be slightly lower than those taken by mouth.

By ear: a special thermometer can quickly measure the temperature of the ear drum, which reflects the body’s core temperature

By skin: a special thermometer can quickly measure the temperature of the skin on the forehead.

A high body temperature is referred to as fever, whereas a low body temperature is called hypothermia.

The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever(temp>38.5C/101.3F or sustained temp>38C/100.4F), or elevated significantly above the individual’s normal temperature.

A fever may occur as a reaction to:

. An infection-most common cause of fever

. Medicines might include antibiotics, narcotics, antihistamines, and many others. This is called “drug fever”

. severe trauma or injury, this may include heat attack, stroke, heatstroke, or burns.

.Other medical conditions including arthritis, hyperthyroidism, and even some cancers, such as leukemia and lung cancer.

Hypothermia can be serious or even deadly. Low body temperature usually happens form being out in very cold weather. But it may also be caused by alcohol or drug use, going into shock, or certain disorders such as diabetes or low thyroid.

Low body temperature occurring with infection are mostly common in newborns, older adults, or people who are frail.

Respiration rate

The respiration rate is the number of breaths a person takes per minute. The rate is usually measured when a person is at rest and simply involves counting the number of breaths for one minute by counting how many times the chest rises. Respiration rates may increases with fever, illness, and with other medical conditions. When checking respiration, it is important to also note whether a person has any difficulty breathing.

Normal respiration rates for an adult person at rest range from 12 to 16 breaths per minute.

When we breathe more than the medical norm, we lose CO2 and reduce body oxygenation. Hence, an increase in respiratory rate leads to reduced cell oxygenation, while slower and easier breathing improves cell-oxygen content.

Evidence suggests that an adult with a respiratory rate of over 20 breaths/minute is probably unwell, and an adult with a respiratory rate of over 24 breaths/minute is likely to be critically ill.

Pulse or heart rate

The pulse is a measurement of the heart rate, or the number of times the heart beats per minute. As the heart pushes blood through the arteries expand and contract with the flow of the blood. Taking a pulse not only measures the heart rate, but also can indicate the following:

Heart rhythm and strength of the pulse.

The normal pulse for healthy adults ranges form 60-100 beats per minute. The pulse rate may fluctuate and increase with exercises, illness, injury, and emotions.

Many conditions can change your pulse rate. Your doctor will talk with you about any abnormal results that may be related to your symptoms and past health.

A fast heart rate may be caused by:

.Activity or exercise


.Some medicines, such as decongestants and those used in treating asthma


.Some types of heart disease

.An overactive thyroid gland(hyperthyroidism)

.Stimulants such as caffeine, amphetamines, diet pills, and cigarettes

.Drinking alcohol


A slow resting heart rate may be caused by:

.Some types of heart disease and medicine to treat heart disease

.High levels of fitness

.An under-active thyroid gland(hypothyroidism)

A weak pulse may be caused by:

.A blood clot in your am or leg

.Diseases of the blood vessels(peripheral arterial disease)

.Heart disease and heart failure

Blood pressure

Blood pressure is measured with a pressure cuff and stethoscope is the force of the blood pushing against the artery walls. Each time the heart beast, it pumps blood into the arteries, resulting in the highest blood pressure as the heart contracts.

One cannot take his or her own blood pressure unless an electronic unless an electronic blood pressure monitoring device is used.

Two numbers are recorded when measuring blood pressure. The higher number, or systolic pressure, refers to the pressure inside the artery when the heart contracts and pumps blood through the body.

The lower number, or diastolic pressure, refers to the pressure inside the artery when the heart is at rest and is filling with blood. Both the systolic and diastolic pressures are recorded as “mmHg”(millimeters of mercury).  

A normal blood pressure is defined with number less than 120mmHg systolic pressure and less than 90mmHg diastolic pressure.

A high blood pressure, also know as hypertension-140 mmHg or higher systolic pressure and 90 mmHg or higher diastolic pressure- increases the risk of coronary heart disease(heart attack) and stroke. With high blood pressure, the arteries may have an increased resistance against the flow of blood, causing the heart to pump harder to circulate the blood.

Prehypertension is indicated by numbers of 120mmHg-139mmHg systolic pressure and 80mm-89 mmHg and indicates a risk towards developing a hypertension.

These numbers should be used as a guide only. A single elevated blood pressure measurements is not necessarily an indication of a problem. A person who normally runs a lower than usual blood pressure may be considered as hypotensive.


The above article serves only as reference. Kindly refer to your primary care provider for complete consultation and treatment.

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