Vital Signs - (Heart Rate, Blood Pressure, Respiratory Rate, Oxygen Saturation and Temperature)

Vital signs are a clinical snapshot of a patient’s status at a point in time. They create a picture of whether a patient is stable vs unstable. There are five vital signs which are heart rate, blood pressure, respiratory rate, oxygen saturation and temperature. You may also consider including pain/pain scale to this list as well.

Treat the patient, not the monitor

Your overall assessment should include your clinical gestalt of the patient (How they appear? Does their appearance correlate to their vitals?), plus the objective data you get from monitors and laboratory tests. The entirety of all of this information together is more helpful than interpreting the individual parts on their own.

Normal Vital Signs

Heart Rate (HR, Pulse)

Definition: The heart rate is the number of times your heart beats per minute. In a healthy individual you can take the pulse for 15 seconds and multiply the count by 4 or 30 seconds and multiply the count by 2. It is highly recommended that you record a heart rate for a full minute if an irregular heart rate is detected (atrial fibrillation, tachycardia, abnormal arrhythmia, etc). A normal heart rate is from 60-100 beats per minute. Pulse rates vary vastly from person to person and also varies based on underlying medical diseases or a particular diagnosis. When you are sleeping your heart rate is lower, but when you exercise your pulse increases due to increased oxygen demand placed on your body.

Location: Your pulse can be measured by pressing the first and second fingertips against certain points on the body. The most common locations to check for heart rate (pulse) are the radial artery, carotid artery, femoral artery, popliteal artery, temporal artery.

Abnormalities: An increased pulse can indicate infection, dehydration, stress, anxiety, a thyroid disorder, shock, anemia or certain heart conditions (atrial fibrillation, ventricular tachycardia, atrial flutter, substance abuse, caffeine, heart failure, etc). A decreased pulse can indicate bradycardia, coronary artery disease, endocarditis, heart attack, hypothyroidism, electrolyte imbalance, etc. Medications: Beta blockers and digoxin are examples of medications that can slow your pulse. Sympathomimetics (cocaine, amphetamines) and atropine are examples of medications that can speed up your pulse.

Blood Pressure (BP)

Definition: Blood pressure is a measure of the pressure of circulating blood against a blood vessel wall. The top number known as the systolic BP is the amount of pressure that your heart pumps through your arteries and entire body. The bottom number is known as the diastolic BP is the amount of pressure in the arteries and body when your heart is at rest. The normal BP reading is 120/80. Blood pressure is measured in mmHg.

Practice Case
Motor Vehicle Accident
A man arrives unconscious after an accident. His heart rate is 114 and blood pressure 76/44. You are concenred that he has a pelvic fracture. What parenteral fluids are indicated?
Answer Case

Location: Typically you use the blood pressure cuff on the patient’s upper arm. This then squeezes the brachial artery and cuts off the blood supply for just a few seconds when the cuff is inflated. Then when you slowly release the air from the cuff you listen for the blood rushing through the brachial artery when the blood supply returns. To put it simply the first sound that you hear when you release the air out of the BP cuff is the systolic (top) number. The last sound you hear is the diastolic (bottom) number.

Abnormalities: There are many different medical conditions that cause high and low blood pressure. High blood pressure (hypertension) can be caused from heart attacks, stroke, aneurysm, kidney disease, illegal drug use [cocaine, amphetamines], excess of salt in your diet, stress, diabetes, etc. Low blood pressure (hypotension) can be caused from shock, hemorrhage, dehydration, diarrhea, severe infection (sepsis), severe allergic reaction (anaphylaxis), and heart failure. Medications: Midodrine and norepinephrine, are examples of medications that raise blood pressure. Furosemide (diuretic), propranolol (beta blocker), and lisinopril (ACE inhibitor) lower blood pressure.

Practice Case
Chest Pain & Facial Droop
A man has sudden onset sharp chest pain, subsequently followed by a facial droop. What assessment can further determine the cause of these signs and symptoms?
Answer Case

Respiratory Rate (RR)

Definition: Respiratory rate is the number of breaths taken per minute. With each breath, gases are exchanged between the environment and the person’s body. Typically respiratory rate can be measured by counting the number of times the chest rises and falls. A normal respiratory rate is 10-20 breaths per minute. However, anyone breathing at 20 or above is tachypneic with signs of true respiratory distress (e.g., accessory muscle use, speaking in short sentences etc).

Location: Inspect the chest for equal rise and fall on both sides. You can also place your hands on the patient’s chest and check for thoracic expansion. Then count the number of times the chest rises and falls in one minute. Then listen to the lungs for abnormal breath sounds.

Abnormalities: A patient can show signs of breathing too quickly (hyperventilation) or breathing too slowly (hypoventilation) depending on the underlying pathology.

Arterial Blood Gas (ABG)

  1. Respiratory Acidosis - reduced rate of respiration in the body resulting in increased amounts of CO2 in the body. Increases H+ ions reduces pH = more acidic. Can occur with conditions such as emphysema, asthma, and pneumonia.

  2. Respiratory Alkalosis - the rate of respiration increases. The carbon dioxide is exhaled quickly. Decrease in H+ ions increasing ph = more alkaline. Occurs in conditions such as physical trauma, anxiety related hyperventilation, low altitude increases respiration rate due to lower oxygen levels. High altitudes can also result in respiratory alkalosis due to decreased amount of circulating red blood cells in the body.

  3. Metabolic Acidosis - high amounts of H+ ions in the body increasing acidity (not due to respiratory conditions). Occurs in ketoacidosis, certain kidney diseases, diarrhea. Symptoms - headaches, palpitations, abdominal pain, muscle weakness, kussmaul’s breathing. Purpose to increase the amount of carbon dioxide exhaled.

  4. Metabolic Alkalosis - increased ph of the body fluids. Low H+ ions levels there for decreased acidity (not due to respiratory conditions). Can occur in vomiting, excess ingestion of alkaline medications. Symptoms - Abnormal sensations, tachycardia, tetany, abnormal heart rhythm.

Tip: Respiratory compensation - increased or decreased breathing rate to help balance pH levels.

Medications: Opioids or narcotic drug overdoses, sedatives, alcohol can slow your breathing to dangerously low levels and cause severe respiratory depression. Nebulizer treatments (ipratropium bromide) can assist a patient to breathe better if they are experiencing rapid breathing and shortness of breath secondary to airway obstruction/inflammation.

Oxygen Saturation (SpO2, O2 Sats)

Definition: The body needs oxygen to function properly. Without oxygen the body can shut down leading to multiple organ failure. The oxygen that is breathed in through your lungs is transported by hemoglobin in the bloodstream to your cells. Oxygen is used by your cells to create energy, known as adenosine-triphosphate (ATP). Within a single hemoglobin molecule there can be a max of 4 oxygen molecules to provide 100% SpO2. This value tells us how oxygenated a patient is based off of how much oxygen the hemoglobin molecules can carry within their body. A normal SpO2 is 95%-100%. Abnormal is less than 95% SpO2. However, in certain medical conditions such as COPD a person’s SpO2 can be within the range of 88%-92%. The most important thing to remember is to recognize the patient’s baseline oxygen level before you start increasing someone’s oxygen unnecessarily and over oxygenating a patient which can lead to oxygen toxicity or reflex hypoventilation.

Location: An oxygen sensor is placed on the patient’s finger, toe, or even earlobe. Keep in mind that if a patient’s fingers are cold, the patient’s fingers are moving, or nail pollish on the patient’s finger, the oxygen sensor won’t read correctly. Be mindful to pick a site that you can place the oxygen sensor on to get the most accurate result. Another way to measure oxygen saturation is with an invasive measure known as an arterial blood gas (ABG). This involves drawing blood from the radial artery and analyzing the laboratory results.

Abnormalities: Low SpO2 conditions are anemia, CHF, COPD, asthma, ARDS, and strong narcotic medications. High SpO2 is normal however, for a patient with COPD who has damaged alveoli giving too much oxygen can cause oxygen toxicity (headache, sleepiness, confusion). Giving too much oxygen to a COPD patient can cause hyperoxic hypercarbia leading to decreased respiratory drive, respiratory acidosis and death.

Medications: Oxygen is the main form of medication however, it can be administered in various ways depending on the patient’s condition. Oxygen is listed from the least aggressive to the most aggressive oxygen delivery systems:

  • Low-Flow Nasal Cannula (LFNC) 1-6L/min - used for mild hypoxia typically used on inpatient telemetry and medical units.

  • Simple face mask 5-10L/min aka Hudson mask - not commonly used anymore, used for mild hypoxia on inpatient medical and telemetry units. Venturi Mask 2L-15L/min - used for moderate hypoxia. Typically an accurate way of giving oxygen especially to COPD patients. Used for mild-moderate hypoxia typically used on inpatient telemetry and medical units.

  • OxyMask 2L-15L/min - used for mild hypoxia typically used on inpatient telemetry and medical units.

  • Non-rebreather mask 15L/min - used for acutely unwell patients (for short term only) typically in the emergency room setting, tele/medical units, ambulance.

  • Bag-valve mask (aka ambu-bag) 15L/min - this is used when a patient is typically unconscious or is struggling to breathe on their own with less than 8 breaths per minute. Typically seen in emergency rooms, ambulances, lifeflight helicopters, hospital crash carts, ICU settings, inpatient medical and telemetry units.

  • Endotracheal tube - Used in a patient who is not adequately ventilating or oxygenating. This is an emergency intervention that is done to protect and establish airway patency, prevent aspirations into the lungs and secure the airway to allow mechanical or bvm ventilation. Typically performed in the ambulance, lifeflight helicopters, emergency rooms, and intensive care units.

  • Invasive Ventilation - when a patient can’t breathe on their own and needs assistance in breathing to control rate, volume and percentage of oxygen delivery typically used in the intensive care unit and operating room in conjunction with an endotracheal tube.

Oxygen delivery devices based on specific medical conditions:

  • High-Flow Nasal Cannula (HFNC) - Oxygen capable of delivering up to 100% humidified and heated oxygen at a flow rate of up to 60 liters per minute instead of the LFNC at 6 liters per minute. The high flow rate delivers volumes of air over what a patient ventilates physiologically, which increases ventilation and allows for displacement of excess CO2 with excess O2. Used in patients with Acute Hypoxemic Respiratory Failure, Acute Heart Failure /Pulmonary edema, Hypercapnic Respiratory Failure, COPD, Pre & Post extubation Oxygenation, Obstructive Sleep Apnea and Do Not Intubate the patient.

  • CPAP (positive pressure to the lungs at all times) - treats O2 by keeping the airways open for patients with sleep apnea or CHF.

  • BIPAP (high positive pressure on inspiration and lower positive pressure on expiration) - treats CO2 by keeping the airways open in patients with COPD. Tracheostomy tube - Known as a ‘trach’, this oxygen device is typically used in patients who need an alternative airway either temporary or permanent through the person’s neck. This is used for patients who have heavy facial trauma (GSW to the face), obstructed upper airway, anaphylaxis, chronic smoker, laryngeal cancer.


Definition: Normal body temperature ranges from 97.8 degrees fahrenheit to 100.4 degrees fahrenheit. Body temperature varies based on age, menstrual cycle, food consumption, gender, etc.

Location: Temperature can be taken with a thermometer by mouth (orally), rectally (most accurate for core body temperature), under the armpit (axillary), on the side of the upper forehead (temporally), and in the ear drum (tympanic).

Abnormalities: High body temperature (febrile temperature) is when your body temperature is above 100.4F (38C) due to fever or infection. Low body temperature is when your body drops below 95 degrees fahrenheit. Please keep in mind there are subcategories for low body temperature. If this is not treated the brain and body cannot function properly and the patient can go into cardiac arrest.

Medications: Medications that lower body temperature are known as antipyretics (ibuprofen, acetaminophen, naproxen) that help reduce fever symptoms but they do not treat the illness or underlying cause of the fever.

Remember to treat the patient, not the monitor

Vital signs provide the clinician with an overall snapshot of a patient’s well being and can help determine treatment and management plans for patients when taken into consideration with other data points and the entire patient as a whole. When vital signs are abnormal, first check to see how the patient is doing. If they appear well and but the vital sign suggests otherwise, remember to treat the patient as a whole and not just individual numbers.

Alexander Tataryn
Alexander Tataryn

As a Medical-Surgical/Telemetry Nurse, Alex enjoys every single moment of what he does - whether it's as simple as putting a warm blanket on a patient to lifesaving procedures like CPR, he takes pride in all of it. Based in Portland, Oregon, he enjoys hiking, weightlifting and video games.

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