Vital signs
Encyclopedia
Vital signs are measures of various physiological statistics, often taken by health professionals, in order to assess the most basic body functions. Vital signs are an essential part of a case presentation
. The act of taking vital signs normally entails recording body temperature
, pulse
rate (or heart rate
), blood pressure
, and respiratory rate
, but may also include other measurements. Vital signs often vary by age.
The equipment needed is a thermometer
, a sphygmomanometer
, and a watch
.
Though a pulse can often be taken by hand, a stethoscope
may be required for a patient with a very weak pulse.
) as it affects the rate of chemical reactions.
Temperature can be recorded in order to establish a baseline for the individual's normal temperature for the site and measuring conditions. The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever
(temp > 38.5°C or sustained temp > 38°C), or elevated significantly above the individual's normal temperature. Other causes of elevated temperature include hyperthermia
.
Temperature depression (hypothermia
) also needs to be evaluated. It is also noteworthy to review the trend of the patient's temperature. A patient with a fever of 38°C does not necessarily indicate an ominous sign if his previous temperature has been higher. Body temperature is maintained through a balance of the heat produced by the body and the heat lost from the body.
pressure, which is the maximal contraction of the heart, and the lower diastolic or resting pressure. A normal blood pressure would be 120 being the systolic over 80, the diastolic. Usually the blood pressure is read from the left arm unless there is some damage to the arm. The difference between the systolic and diastolic pressure is called the pulse pressure
. The measurement of these pressures is now usually done with an aneroid
or electronic sphygmomanometer
. The classic measurement device is a mercury
sphygmomanometer, using a column of mercury measured off in millimeters. In the United States and UK, the common form is millimeters of mercury, whilst elsewhere SI
units of pressure are used. There is no natural 'normal' value for blood pressure, but rather a range of values that on increasing are associated with increased risks. The guideline acceptable reading also takes into account other co-factors for disease. Therefore, elevated blood pressure (hypertension
) is variously defined when the systolic number is persistently over 140–160 mmHg. Low blood pressure is hypotension
. Blood pressures are also taken at other portions of the extremities. These pressures is called segmental blood pressure
s and are used to evaluate blockage or arterial occlusion in a limb
(see Ankle brachial pressure index
).
at the wrist. Sometimes the pulse cannot be taken at the wrist and is taken at the elbow (brachial artery
), at the neck against the carotid artery
(carotid pulse), behind the knee (popliteal artery
), or in the foot dorsalis pedis
or posterior tibial arteries
. The pulse rate can also be measured by listening directly to the heartbeat
using a stethoscope
. The pulse varies with age. A newborn or infant
can have a heart rate of about 130-150 beats per minute. A toddler
's heart will beat about 100-120 times per minute, an older child's heartbeat
is around 90-110 beats per minute, adolescents around 80-100 beats per minute, and adults pulse rate is anywhere between 50 and 80 beats per minute.
Respiratory rate is clear indicator of acidotic states, as the main function of respiration is removal of CO2 leaving bicarbonate base in circulation.
, as perceived by the patient on a Pain scale
of 0–10. For example, the Veterans Administration
made this their policy in 1999. However, some doctors have noted that pain is actually a subjective symptom
, not an objective sign
, and therefore object to this classification.
Other sources include oxygen saturation
as their fifth sign.
Some sources consider pupil
size, equality, and reactivity to light to be a vital sign as well.
Many EMS agencies in the USA use Pulse Oximetry and Blood Glucose Level as vital signs in addition to pulse, respiratory rate, and blood pressure.
Case presentation
A case presentation is a formal communication between health care professionals regarding a patient's clinical information...
. The act of taking vital signs normally entails recording body temperature
Thermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different...
, pulse
Pulse
In medicine, one's pulse represents the tactile arterial palpation of the heartbeat by trained fingertips. The pulse may be palpated in any place that allows an artery to be compressed against a bone, such as at the neck , at the wrist , behind the knee , on the inside of the elbow , and near the...
rate (or heart rate
Heart rate
Heart rate is the number of heartbeats per unit of time, typically expressed as beats per minute . Heart rate can vary as the body's need to absorb oxygen and excrete carbon dioxide changes, such as during exercise or sleep....
), blood pressure
Blood pressure
Blood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
, and respiratory rate
Respiratory rate
Respiratory rate is also known by respiration rate, pulmonary ventilation rate, ventilation rate, or breathing frequency is the number of breaths taken within a set amount of time, typically 60 seconds....
, but may also include other measurements. Vital signs often vary by age.
Primary four
There are four vital signs which are standard in most medical settings:- Body temperatureThermoregulationThermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different...
- PulsePulseIn medicine, one's pulse represents the tactile arterial palpation of the heartbeat by trained fingertips. The pulse may be palpated in any place that allows an artery to be compressed against a bone, such as at the neck , at the wrist , behind the knee , on the inside of the elbow , and near the...
rate (or heart rateHeart rateHeart rate is the number of heartbeats per unit of time, typically expressed as beats per minute . Heart rate can vary as the body's need to absorb oxygen and excrete carbon dioxide changes, such as during exercise or sleep....
) - Blood pressureBlood pressureBlood pressure is the pressure exerted by circulating blood upon the walls of blood vessels, and is one of the principal vital signs. When used without further specification, "blood pressure" usually refers to the arterial pressure of the systemic circulation. During each heartbeat, BP varies...
- Respiratory rateRespiratory rateRespiratory rate is also known by respiration rate, pulmonary ventilation rate, ventilation rate, or breathing frequency is the number of breaths taken within a set amount of time, typically 60 seconds....
The equipment needed is a thermometer
Thermometer
Developed during the 16th and 17th centuries, a thermometer is a device that measures temperature or temperature gradient using a variety of different principles. A thermometer has two important elements: the temperature sensor Developed during the 16th and 17th centuries, a thermometer (from the...
, a sphygmomanometer
Sphygmomanometer
A sphygmomanometer or blood pressure meter is a device used to measure blood pressure, comprising an inflatable cuff to restrict blood flow, and a mercury or mechanical manometer to measure the pressure. It is always used in conjunction with a means to determine at what pressure blood flow is just...
, and a watch
Watch
A watch is a small timepiece, typically worn either on the wrist or attached on a chain and carried in a pocket, with wristwatches being the most common type of watch used today. They evolved in the 17th century from spring powered clocks, which appeared in the 15th century. The first watches were...
.
Though a pulse can often be taken by hand, a stethoscope
Stethoscope
The stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal body. It is often used to listen to lung and heart sounds. It is also used to listen to intestines and blood flow in arteries and veins...
may be required for a patient with a very weak pulse.
Temperature
Temperature recording gives an indication of core body temperature which is normally tightly controlled (thermoregulationThermoregulation
Thermoregulation is the ability of an organism to keep its body temperature within certain boundaries, even when the surrounding temperature is very different...
) as it affects the rate of chemical reactions.
Temperature can be recorded in order to establish a baseline for the individual's normal temperature for the site and measuring conditions. The main reason for checking body temperature is to solicit any signs of systemic infection or inflammation in the presence of a fever
Fever
Fever is a common medical sign characterized by an elevation of temperature above the normal range of due to an increase in the body temperature regulatory set-point. This increase in set-point triggers increased muscle tone and shivering.As a person's temperature increases, there is, in...
(temp > 38.5°C or sustained temp > 38°C), or elevated significantly above the individual's normal temperature. Other causes of elevated temperature include hyperthermia
Hyperthermia
Hyperthermia is an elevated body temperature due to failed thermoregulation. Hyperthermia occurs when the body produces or absorbs more heat than it can dissipate...
.
Temperature depression (hypothermia
Hypothermia
Hypothermia is a condition in which core temperature drops below the required temperature for normal metabolism and body functions which is defined as . Body temperature is usually maintained near a constant level of through biologic homeostasis or thermoregulation...
) also needs to be evaluated. It is also noteworthy to review the trend of the patient's temperature. A patient with a fever of 38°C does not necessarily indicate an ominous sign if his previous temperature has been higher. Body temperature is maintained through a balance of the heat produced by the body and the heat lost from the body.
Blood pressure
The blood pressure is recorded as two readings; a high systolicSystole (medicine)
Systole is the contraction of the heart. Used alone, it usually means the contraction of the left ventricle.In all mammals, the heart has 4 chambers. The left and right ventricles pump together. The atria and ventricles pump in sequence...
pressure, which is the maximal contraction of the heart, and the lower diastolic or resting pressure. A normal blood pressure would be 120 being the systolic over 80, the diastolic. Usually the blood pressure is read from the left arm unless there is some damage to the arm. The difference between the systolic and diastolic pressure is called the pulse pressure
Pulse pressure
Pulse Pressure is most easily defined as being the amount of pressure required to create the feeling of a pulse. Measured in millimeters of mercury , the pressure difference between the systolic and diastolic pressures give you the amount of pressure change to create the pulse, which is the pulse...
. The measurement of these pressures is now usually done with an aneroid
Aneroid
Aneroid may mean*The village of Aneroid, Saskatchewan*"without fluid", particularly in reference to barometers...
or electronic sphygmomanometer
Sphygmomanometer
A sphygmomanometer or blood pressure meter is a device used to measure blood pressure, comprising an inflatable cuff to restrict blood flow, and a mercury or mechanical manometer to measure the pressure. It is always used in conjunction with a means to determine at what pressure blood flow is just...
. The classic measurement device is a mercury
Mercury (element)
Mercury is a chemical element with the symbol Hg and atomic number 80. It is also known as quicksilver or hydrargyrum...
sphygmomanometer, using a column of mercury measured off in millimeters. In the United States and UK, the common form is millimeters of mercury, whilst elsewhere SI
Si
Si, si, or SI may refer to :- Measurement, mathematics and science :* International System of Units , the modern international standard version of the metric system...
units of pressure are used. There is no natural 'normal' value for blood pressure, but rather a range of values that on increasing are associated with increased risks. The guideline acceptable reading also takes into account other co-factors for disease. Therefore, elevated blood pressure (hypertension
Hypertension
Hypertension or high blood pressure is a cardiac chronic medical condition in which the systemic arterial blood pressure is elevated. What that means is that the heart is having to work harder than it should to pump the blood around the body. Blood pressure involves two measurements, systolic and...
) is variously defined when the systolic number is persistently over 140–160 mmHg. Low blood pressure is hypotension
Hypotension
In physiology and medicine, hypotension is abnormally low blood pressure, especially in the arteries of the systemic circulation. It is best understood as a physiologic state, rather than a disease. It is often associated with shock, though not necessarily indicative of it. Hypotension is the...
. Blood pressures are also taken at other portions of the extremities. These pressures is called segmental blood pressure
Segmental blood pressure
Segmental blood pressure is used to measure actual limb blood pressures. The purpose of these measurements is to look at arterial occlusion....
s and are used to evaluate blockage or arterial occlusion in a limb
Limb (anatomy)
A limb is a jointed, or prehensile , appendage of the human or other animal body....
(see Ankle brachial pressure index
Ankle brachial pressure index
The Ankle Brachial Pressure Index , known more commonly as an ABI, is the ratio of the blood pressure in the lower legs to the blood pressure in the arms. Compared to the arm, lower blood pressure in the leg is an indication of blocked arteries...
).
Pulse
The pulse is the physical expansion of the artery. Its rate is usually measured either at the wrist or the ankle and is recorded as beats per minute. The pulse commonly taken is from the radial arteryRadial artery
In human anatomy, the radial artery is the main blood vessel, with oxygenated blood, of the lateral aspect of the forearm.-Course:The radial artery arises from the bifurcation of the brachial artery in the cubital fossa. It runs distally on the anterior part of the forearm...
at the wrist. Sometimes the pulse cannot be taken at the wrist and is taken at the elbow (brachial artery
Brachial artery
The brachial artery is the major blood vessel of the arm.It is the continuation of the axillary artery beyond the lower margin of teres major muscle. It continues down the ventral surface of the arm until it reaches the cubital fossa at the elbow. It then divides into the radial and ulnar arteries...
), at the neck against the carotid artery
Carotid artery
Carotid artery can refer to:* Common carotid artery* External carotid artery* Internal carotid artery...
(carotid pulse), behind the knee (popliteal artery
Popliteal artery
In human anatomy, the popliteal artery is defined as the extension of the "superficial" femoral artery after passing through the adductor canal and adductor hiatus above the knee...
), or in the foot dorsalis pedis
Dorsalis pedis artery
In human anatomy, the dorsalis pedis artery , is a blood vessel of the lower limb that carries oxygenated blood from the dorsal surface of the foot. It arises at the anterior aspect of the ankle joint and is a continuation of the anterior tibial artery...
or posterior tibial arteries
Posterior tibial artery
The posterior tibial artery of the lower limb carries blood to the posterior compartment of the leg and plantar surface of the foot, from the popliteal artery...
. The pulse rate can also be measured by listening directly to the heartbeat
Cardiac cycle
The cardiac cycle is a term referring to all or any of the events related to the flow or blood pressure that occurs from the beginning of one heartbeat to the beginning of the next. The frequency of the cardiac cycle is described by the heart rate. Each beat of the heart involves five major stages...
using a stethoscope
Stethoscope
The stethoscope is an acoustic medical device for auscultation, or listening to the internal sounds of an animal body. It is often used to listen to lung and heart sounds. It is also used to listen to intestines and blood flow in arteries and veins...
. The pulse varies with age. A newborn or infant
Infant
A newborn or baby is the very young offspring of a human or other mammal. A newborn is an infant who is within hours, days, or up to a few weeks from birth. In medical contexts, newborn or neonate refers to an infant in the first 28 days after birth...
can have a heart rate of about 130-150 beats per minute. A toddler
Toddler
A toddler is a young child, usually defined as being between the ages of one and three. Registered nurse, midwife and author, Robin Barker, states 'Any time from eight months onwards your baby will begin to realise he is a separate person from you...
's heart will beat about 100-120 times per minute, an older child's heartbeat
Cardiac cycle
The cardiac cycle is a term referring to all or any of the events related to the flow or blood pressure that occurs from the beginning of one heartbeat to the beginning of the next. The frequency of the cardiac cycle is described by the heart rate. Each beat of the heart involves five major stages...
is around 90-110 beats per minute, adolescents around 80-100 beats per minute, and adults pulse rate is anywhere between 50 and 80 beats per minute.
Respiratory rate
Varies with age, but the normal reference range for an adult is 10–20 breaths/minute. The value of respiratory rate as an indicator of potential respiratory dysfunction has been investigated but findings suggest it is of limited value.Respiratory rate is clear indicator of acidotic states, as the main function of respiration is removal of CO2 leaving bicarbonate base in circulation.
Additional signs
While various additional signs have been proposed, none have been officially universally adopted due to the expense in obtaining equipment required to diagnose and the difficulty in training entry-level professionals.Fifth sign
The phrase "fifth vital sign" usually refers to painPain
Pain is an unpleasant sensation often caused by intense or damaging stimuli such as stubbing a toe, burning a finger, putting iodine on a cut, and bumping the "funny bone."...
, as perceived by the patient on a Pain scale
Pain scale
A pain scale measures a patient's pain intensity or other features. Pain scales are based on self-report, observational , or physiological data. Self-report is considered primary and should be obtained if possible. Pain scales are available for neonates, infants, children, adolescents, adults,...
of 0–10. For example, the Veterans Administration
United States Department of Veterans Affairs
The United States Department of Veterans Affairs is a government-run military veteran benefit system with Cabinet-level status. It is the United States government’s second largest department, after the United States Department of Defense...
made this their policy in 1999. However, some doctors have noted that pain is actually a subjective symptom
Symptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...
, not an objective sign
Medical sign
A medical sign is an objective indication of some medical fact or characteristic that may be detected by a physician during a physical examination of a patient....
, and therefore object to this classification.
Other sources include oxygen saturation
Oxygen saturation
Oxygen saturation or dissolved oxygen is a relative measure of the amount of oxygen that is dissolved or carried in a given medium. It can be measured with a dissolved oxygen probe such as an oxygen sensor or an optode in liquid media, usually water.It has particular significance in medicine and...
as their fifth sign.
Some sources consider pupil
Pupil
The pupil is a hole located in the center of the iris of the eye that allows light to enter the retina. It appears black because most of the light entering the pupil is absorbed by the tissues inside the eye. In humans the pupil is round, but other species, such as some cats, have slit pupils. In...
size, equality, and reactivity to light to be a vital sign as well.
Many EMS agencies in the USA use Pulse Oximetry and Blood Glucose Level as vital signs in addition to pulse, respiratory rate, and blood pressure.
Sixth sign
There is no standard "sixth vital sign", and the use is much more informal and discipline-dependent than with the above, but some proposals (excluding the fifth sign candidates above) include:- Shortness of breath
- Molecular GeneticsMolecular geneticsMolecular genetics is the field of biology and genetics that studies the structure and function of genes at a molecular level. The field studies how the genes are transferred from generation to generation. Molecular genetics employs the methods of genetics and molecular biology...
, in OncologyOncologyOncology is a branch of medicine that deals with cancer... - Gait Speed
- Body Mass IndexBody mass indexThe body mass index , or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing...
Variations by age
Children and infants have respiratory and heart rates that are faster than those of adults as shown in the following table:| Age | Normal heart rate (beats per minute) |
Normal respiratory rate (breaths per minute) |
|---|---|---|
| Newborn | 100-160 | 30-50 |
| 0–5 months | 90-150 | 25-40 |
| 6–12 months | 80-140 | 20-30 |
| 1–3 years | 80-130 | 20-30 |
| 3–5 years | 80-120 | 20-30 |
| 6–10 years | 70-110 | 15-30 |
| 11–14 years | 60-105 | 12-20 |
| 14+ years | 60-100 | 12-20 |