Terms related to vital signs

Introduction to 4 main vital signs

The 4 main vital signs are essential measurements of the basic body functions and provide critical information about an individual’s health status.

These signs are usually measured in a medical context, often by healthcare professionals, and can give a quick, valuable snapshot of how well the body’s vital systems are functioning.

They serve as the first line of assessment in any medical examination, providing preliminary information that can guide further diagnostic procedures and treatment options.

The 4 main vital signs typically monitored are body temperature, heart rate (or pulse), breathing rate (or respiratory rate), and blood pressure.

Body temperature indicates the body’s overall thermal regulation, while the heart rate measures the number of times the heart beats per minute.

The breathing rate counts the number of breaths taken per minute and provides insight into respiratory health. Lastly, blood pressure signifies the force exerted by the blood against the walls of the arteries, which can indicate cardiovascular health or risk factors.

Regular monitoring and recording of these 4 main vital signs can detect early warning signs of medical issues or complications, allowing for timely intervention.

Furthermore, they provide a baseline for patient care, enabling healthcare providers to monitor a patient’s response to treatment over time and adjust care plans as needed.

Definition and explanation of terms related to vital signs

Before delving into the specifics of 4 main vital signs, it is important to understand the terminology associated with them. Body temperature, pulse, respiration, and blood pressure are the 4 main vital signs that are routinely measured.

These measurements provide valuable insights into the body’s functioning and serve as vital indicators of health or illness. Following are the key terms related to the vital signs directly or indirectly.

4 main vital signs


1. Febrile: Febrile refers to a state of having a fever, which is characterized by an elevated body temperature above the normal range.

2. Afebrile: It refers to the absence of fever. An afebrile patient does not have an elevated body temperature. This term is often used to describe individuals who do not exhibit any signs of fever during a medical examination or assessment

3. Hypothermia: Hypothermia refers to a condition where the body temperature drops below the normal range.

4. Pyrexia: Pyrexia is a general term that encompasses both febrile and hyperpyrexia, indicating an elevated body temperature regardless of the specific cause.

5. Hyperpyrexia: Hyperpyrexia is an extreme form of fever where the body temperature rises significantly above 40 degrees Celsius.

6. Antipyretic: An antipyretic is a medication or treatment that is used to reduce or alleviate fever. It works by lowering the body temperature and providing relief from symptoms associated with fever, such as discomfort and fatigue. Commonly used antipyretic medications include acetaminophen and ibuprofen.

7. Constant fever: It is a term used to describe a condition where a person has a consistently high body temperature over an extended period. Unlike intermittent or periodic fevers, which come and go, a constant fever persists without any significant fluctuations.

This can be an indication of an underlying medical condition that requires further investigation and treatment.

8. Intermittent fever: This refers to a type of fever that comes and goes at regular intervals. It is characterized by periods of elevated body temperature followed by periods of normal temperature.

Intermittent fever can be caused by various factors such as infections, inflammatory conditions, or certain medications.


9. Relapsing fever: This is a type of fever characterized by recurrent episodes of fever separated by periods of normal temperature. Unlike intermittent fever, which has regular intervals, relapsing fever episodes are often unpredictable and irregular.

Relapsing fever is commonly caused by bacterial infections, such as those transmitted by ticks or lice. It is important to promptly diagnose and treat relapsing fever to prevent complications and further spread of the infection.

10. Remittent fever: Remittent fever is a type of fever characterized by fluctuations in body temperature throughout the day, where the temperature does not return to normal during the day.

This can be seen in various infectious diseases and can indicate an ongoing inflammatory process in the body.

11. Diaphoresis: It refers to excessive sweating, often accompanied by a feeling of heat or warmth. It is the body’s natural response to regulate temperature and can occur as a result of physical exertion, stress, or certain medical conditions.

Diaphoresis can be a symptom of an underlying issue, such as an infection or hormonal imbalance, and should be evaluated by a healthcare professional if persistent or accompanied by other concerning symptoms.

12. Thermometer: A device that measures the body’s temperature and provides an accurate reading. There are different types of thermometers available, including oral, rectal, ear, and forehead thermometers.

Each type has its advantages and disadvantages, and the choice of thermometer depends on the age and condition of the patient.

13. Thermoregulation: It is a continuous and constant process of regulation of normal body temperature.


1. Pulse: A wave that enters the arteries with each contraction of the left ventricle of the heart which can be felt or heard is called a pulse.

2. Peripheral pulse: It refers to the palpable pulsation felt in peripheral arteries, such as the radial artery in the wrist or the carotid artery in the neck. It is used as a diagnostic tool to assess the heart rate and rhythm.

The strength and regularity of peripheral pulses provide valuable information about cardiovascular function and circulation.

3. Cardiac output: It refers to the amount of blood pumped by the heart in one minute. Cardiac output is a crucial metric of cardiovascular function.

It is determined by multiplying the heart rate by the stroke volume, which is the amount of blood ejected with each heartbeat. This information is valuable because it helps assess the heart’s capacity to supply oxygen and nutrients to the body’s tissues.

4. Bradycardia: It refers to a slower-than-normal heart rate, typically below 60 beats per minute. It can be a normal response to certain conditions such as sleep or relaxation, but it can also indicate an underlying medical condition or medication side effect.

5. Tachycardia: An excessive heart rate of more than 100 beats per minute is called tachycardia.

6. Pulse rhythm: A pattern of the heartbeats and the interval between the heartbeats is known as pulse rhythm. It refers to the regularity or irregularity of the heartbeat.

A regular pulse rhythm indicates a consistent and evenly spaced heartbeat, while an irregular rhythm may indicate underlying cardiac issues.

7. Dysrhythmia: Also known as arrhythmia refers to abnormal electrical activity in the heart. It causes disruptions in the heart’s normal rhythm, leading to irregular heartbeats.

Dysrhythmias can range from mild to severe and can have various causes, including underlying heart conditions, electrolyte imbalances, or drug interactions. Common dysrhythmias include atrial fibrillation, ventricular tachycardia, and bradycardia.

8. Pulse deficit: It is the difference between the heart rate and the pulse rate. It occurs when not all of the heart’s contractions result in a palpable pulse.

9. Pulse Compliance: It refers to the ability of the arterial system to expand and contract in response to the pressure changes caused by the heartbeat. This can be measured by assessing the pulse pressure.


1. Respiration: Respiration is the act of inhalation (inspiration) of oxygen and exhalation (expiration) of carbon dioxide through the lungs. It is a vital function that ensures the delivery of oxygen to all cells in the body and the removal of waste products.

2. Internal Respiration: Internal respiration is a term used to describe the exchange of gases that occurs at the cellular level within the body. It involves the diffusion of oxygen from the bloodstream into the cells and the diffusion of carbon dioxide from the cells into the bloodstream.

Internal respiration takes place in tissues throughout the body and is vital for cellular metabolism and energy production. It should not be confused with external respiration, which refers to the exchange of gases that occurs between the lungs and the external environment during breathing.

3. External respiration: External respiration refers to the process of exchanging gases between the lungs and the bloodstream. During this process, oxygen from the inhaled air diffuses through the walls of the alveoli and enters the bloodstream, as part of metabolism, the body produces carbon dioxide which diffuses from the bloodstream into the alveoli and is then exhaled as a waste product.

4. Inspiration: An inhalation refers to the process of breathing in or taking air inside the lungs. During inspiration, the diaphragm and other respiratory muscles contract, causing the lungs to expand and create a negative pressure. This negative pressure allows air to enter the lungs and oxygen to be delivered to the body’s cells.

5. Expiration: The act of exhalation of carbon dioxide from the lungs is called expiration. During expiration, the diaphragm and intercostal muscles relax, causing a decrease in thoracic volume and an increase in intra-thoracic pressure, which forces air out of the lungs.

6. Ventilation: Ventilation is a term used to describe the process of moving air in and out of the lungs. It involves the exchange of oxygen and carbon dioxide and is essential for proper respiratory functions.

7. Hypoventilation: This refers to a decrease in the rate and depth of breathing. This can lead to a buildup of carbon dioxide in the bloodstream, causing various symptoms such as shortness of breath and confusion. Hypoventilation can occur due to conditions like respiratory depression, lung diseases, or certain medications.

8. Hyperventilation: Hyperventilation is a term used to describe a rapid and deep breathing pattern that leads to an excessive elimination of carbon dioxide from the body. This can occur due to various reasons such as anxiety, panic attacks, or certain medical conditions. Hyperventilation can result in symptoms like lightheadedness, dizziness, and tingling sensations.

9. Respiratory rhythm: Regularity between inspiration and expiration of breaths is called the respiratory rhythm. The respiratory rhythm refers to the pattern of breathing, which is regulated by the brainstem. This rhythm is controlled by various factors, including the levels of carbon dioxide and oxygen in the blood.

10. Tidal volume: Tidal volume refers to the amount of air that is inhaled or exhaled during a normal breath. It is a crucial measurement for assessing lung function and is often used in respiratory therapy to evaluate the efficiency of ventilation. Tidal volume, measured in milliliters (mL), can vary depending on factors such as age, gender, and physical activity levels.

11. Costal breathing: Costal breathing is also known as thoracic breathing. The use of accessory muscles and internal-external costal muscles during respiration is called costal breathing.

Costal breathing can be seen by the movement of the chest, it describes how the ribs and intercostal muscles are used during breathing. Costal breathing involves the expansion and contraction of the ribcage to facilitate air movement in and out of the lungs.

This type of breathing is commonly observed in individuals with respiratory conditions or during strenuous physical activity.

12. Diaphragmatic breathing: Also known as deep breathing or abdominal breathing is a technique that involves the contraction and relaxation of the diaphragm muscle to promote proper oxygen intake and relaxation.

It is characterized by the expansion of the abdomen during inhalation and the contraction of the abdomen during exhalation. Diaphragmatic breathing is commonly used in various practices such as yoga, meditation, and singing to enhance relaxation, reduce stress, and improve overall well-being.

13. Bronchial sound: A loud and high-pitched sound can be heard longer on expiration and shorter on inspiration. It refers to the sound produced by air moving through the larger airways of the lungs. This sound can be heard with a stethoscope during a physical examination.

14. Vesicular sound: A soft and low-pitched sound, resembling a gentle rustling or whispering noise, can be heard longer on inspiration and shorter on expiration is known as vesicular sound.

Vesicular sound refers to the normal breath sounds heard on auscultation of the lungs. Vesicular sounds are produced by the movement of air through the small airways and alveoli in the lungs.

Any deviation from the normal vesicular sound can indicate an underlying respiratory condition or abnormality.

15. Broncho-vesicular sound: A medium-pitched sound that can be heard equally on inspiration and expiration is known as broncho-vesicular sound. This refers to a specific type of sound heard during auscultation of the lungs. It is characterized by a combination of both bronchial and vesicular sounds.

lung sounds

16. Auscultation: It is the process of listening to internal body sounds using a stethoscope. This technique is commonly used to assess the heart, lungs, and other organs.

17. Eupnea: Eupnea is derived from the Greek word “eu” meaning good, and “pnoia” meaning breath, refers to normal breathing. It is the natural, rhythmic pattern of breathing that occurs when an individual is at rest or engaged in light physical activity.

Eupnea is characterized by a regular rate, depth, and pattern of breathing with no signs of difficulty or discomfort. It is an essential physiological process that ensures the proper exchange of oxygen and carbon dioxide in the body.

18. Apnea: It is the temporary cessation of breathing. This can be caused by various factors such as obstructive sleep apnea or respiratory obstruction

19. Dyspnea: It is a term that is used to describe difficulty or discomfort in breathing. It can be a symptom of various underlying conditions, such as asthma, chronic obstructive pulmonary disease (COPD), or heart failure. Dyspnea can range from mild to severe and can significantly impact a patient’s quality of life.

20. Bradypnea: Abnormally slow breathing is called bradypnea. This can be caused by various factors, such as certain medications or medical conditions.

21. Tachypnea: It refers to an abnormally rapid breathing rate. This can be caused by a variety of factors, including infection, anxiety, or metabolic disorders. It’s also called ploypnea.

22. Adventitious breath sounds: Abnormal sounds heard during lung auscultation may indicate underlying respiratory conditions such as asthma or pneumonia. These sounds include wheezing, crackles, or rhonchi. There are three types of normal breath sounds: vesicular, bronchial, and broncho-vesicular.

23. Crackles (Rales): A fine, short, interrupted, and high-pitched crackling sound can be heard on both inspiration and expiration is called crackles. it cannot be cleared by coughing.

Crackles are also called rales. It is an abnormal lung sound that can be heard on auscultation. These sounds are caused by the presence of fluid or mucus in the small airways of the lungs. Crackles can be a sign of various respiratory conditions, such as pneumonia or pulmonary edema.

24. Rhonchi: A continuous, low-pitched, coarse, gurgling, harsh, louder sound with a moaning or snoring quality that can be heard on both inspiration and expiration is called Rhonchi. It can be altered by coughing. This abnormal sound heard during auscultation of the lungs indicates the presence of mucus or fluid in the airways.

25. Stridor: A harsh and noisy, high-pitched sound that can be heard during inspiration is called stridor. It is caused by to narrowing of the airway. Stridor can be a sign of airway obstruction and requires immediate medical attention.

26. Wheezing: Continuous, high-pitched, squeaky musical sounds, that can be heard on expiration is called wheezing. It cannot be altered by coughing. It is commonly associated with conditions such as asthma or bronchitis.

27. Friction rub: A friction rub is a distinctive sound heard during auscultation (listening with a stethoscope) of the chest. It is caused by the rubbing together of inflamed or roughened pleural surfaces due to conditions such as pneumonia, pleurisy, or lung cancer.

The friction rub is often described as a grating or scratching sound that occurs during both inspiration and expiration. It can be heard best when the patient takes deep breaths.

Blood Pressure

1. Blood pressure: it is the force exerted by circulating blood against the walls of blood vessels. It is an important indicator of cardiovascular health and is influenced by factors such as heart rate, cardiac output, and blood volume.

2. Systolic blood pressure: Force exerted by the blood on blood vessels as a result of contraction of ventricles is called systolic blood pressure.

3. Diastolic blood pressure: The lower pressure present at all times in blood vessels when the ventricles are relaxed is called diastolic blood pressure.

4. Mean Arterial Pressure (MAP): Mean arterial pressure (MAP) is a medical term used to describe the average pressure in a person’s arteries during one cardiac cycle. It is calculated by adding two-thirds of the diastolic blood pressure to one-third of the systolic blood pressure. MAP is an important measure as it reflects the perfusion pressure that drives blood flow to vital organs.

5. Hypotension: It refers to abnormally low blood pressure. It is often defined as a systolic blood pressure below 90 mmHg or a diastolic blood pressure below 60 mmHg.

Hypotension can occur due to various factors, such as dehydration, medication side effects, heart problems, or endocrine disorders. Symptoms of hypotension may include dizziness, fainting, fatigue, and confusion.

Treatment for hypotension depends on the underlying cause but often involves lifestyle changes, medication adjustments, or intravenous fluids to increase blood volume.

6. Hypertension: Blood pressure exceeding the normal range is known as hypertension or high blood pressure, which greatly increases the risk of various cardiovascular diseases such as heart attack and stroke.

Hypertension can be classified into two categories: primary hypertension, which has no identifiable cause, and secondary hypertension, which is caused by an underlying medical condition such as kidney disease or hormonal disorders.

7. Orthostatic hypotension: Orthostatic hypotension is a medical condition characterized by a sudden drop in blood pressure when a person stands up from a sitting or lying position. It is also known as postural hypotension.

The term “orthostatic” refers to the change in body position, while “hypotension” refers to low blood pressure. This condition occurs due to an inadequate response from the autonomic nervous system to maintain blood pressure and blood flow to the brain. Symptoms of orthostatic hypotension may include dizziness, lightheadedness, fainting, blurred vision, and even falls.


  • Berman, A., Snyder, S., & Frandsen, G. (2016). Kozier & Erb’s Fundamentals of Nursing: Concepts, Practice, and Process (10th ed.). Pearson.
  • Delaune, S. C., & Ladner, P. K. (2002). Fundamentals of nursing : standards & practice. Delmar Thomson Learning.
  • Patricia Ann Potter, Anne Griffin Perry, Stockert, P. A., & Hall, A. (2018). Essentials for nursing practice. Elsevier
  • Vital Signs Examination Glossary of Terms. (n.d.). Healthcaresciencesocw.wayne.edu. https://healthcaresciencesocw.wayne.edu/vs/glossary.htm
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