Respiratory Therapy Terms and Definitions

A

AARC – the abbreviation for the American Association for Respiratory Care, which the primary nonprofit organization that supports respiratory therapists in the United States.

Accessory Muscles of Breathing – muscles of the neck, back, and abdomen that assist the diaphragm when a patient has an increased work of breathing.

Acid-Base Balance – the process by which the body maintains a proper equilibrium of acids and bases and refers to the degree of acidity and alkalinity.

Acute Exacerbation of COPD – a worsening state of COPD that usually indicates that the patient is in need of increased medication dosages or other forms of care.

Advanced Cardiac Life Support (ACLS) – an advanced form of emergency life support for the treatment of cardiac arrest, stroke, myocardial infarction, and other life-threatening cardiovascular emergencies.

Advanced Directive – a legal document that allows a patient to specify what medical care he or she does or does not want to receive if they were no longer able to make decisions on their own. It’s typically in the form of a living will or durable power of attorney.

Aerosol Medications – a medication that can be dispersed as solid or liquid particles in a gas which allows for inhalation into the airways of the respiratory tract.

Air Bronchograms – a pattern on a chest radiograph that shows air-filled bronchi surrounded by areas of consolidation.

Airway Clearance Therapy – a type of therapy that uses noninvasive techniques to help mobilize and remove secretions in order to improve gas exchange.

Airway Management – the process of maintaining ventilation in a patient by using an artificial airway. This ensures that gas exchange can occur by establishing a link between the patient and the ventilator.

Airway Obstruction – a complete or partial blockage of an airway that prevents or limits ventilation and air movement to and from the lungs.

Airway Pharmacology – a term that refers to the deliverance of aerosol medications to the respiratory tract of the lungs.

Airway Pressure Release Ventilation (APRV) – a mode of mechanical ventilation in which two levels of continuous positive airway pressure are applied with an intermittent release phase for spontaneous breaths. This mode is often recommended to improve oxygenation and treat refractory hypoxemia.

Airway Resistance – the measurement of impedance to the movement of air through the respiratory tract during inspiration and expiration.

Airway Suctioning – a method of using negative pressure to remove secretions from a patient’s airway through a collecting tube or catheter.

Albuterol – an inhaled beta-2-agonist bronchodilator that is administered to prevent and treat wheezing, chest tightness, and shortness of breath caused by pulmonary diseases such as asthma and chronic obstructive pulmonary disease (COPD).

Alveolar-Capillary Membrane – a layer of tissue that serves as a barrier through which gas exchange occurs between the alveoli and pulmonary capillaries.

Alveolar Ventilation – the ventilatory process that takes place in the alveoli of the lungs. This is where the body is able to take in oxygen and remove carbon dioxide.

Alveoli – tiny air sacs that are arranged in clusters within the lungs where the gas exchange of oxygen and carbon dioxide molecules takes place

Ambulation – the process of helping a patient gain the ability to walk without any type of assistance.

Anticholinergic Bronchodilators – a drug that acts on the parasympathetic nervous system by blocking the mechanism of action of the neurotransmitter acetylcholine (ACh) to promote relaxation of the smooth muscles in the airways of the lungs.

Antimicrobial Agents – a class of drugs that work to eliminate potentially harmful microorganisms and prevents them from growing or spreading in the lungs.

Apgar Score – a system that is used to quickly determine the status of the newborn’s overall condition. It should be obtained one minute and five minutes after birth to determine if treatment is needed for the infant.

Apnea – the absence of spontaneous breathing.

Apnea of Prematurity – a disorder that occurs in preterm infants which results in frequent periods of apnea. It is caused by a physiologically underdeveloped respiratory control center in the brain.

Apneustic Breathing – an abnormal breathing pattern that results from an injury to the upper pons in the brain that results in a prolonged inspiratory time followed by inadequate expiration.

Arterial Blood Gas (ABG) – a test that measures the blood levels of oxygen (PaO2), carbon dioxide (PaCO2), and acid-base balance (pH) in the body that is used to assess how well oxygen is being distributed and how well carbon dioxide is being removed.

Artificial Airway – a tube that is inserted into a patient’s trachea in order to maintain breathing and ventilation.

Assist/Control Mode (A/C) – a mode of mechanical ventilation in which a minimum number of preset mandatory breaths are delivered by the ventilator but the patient can also trigger assisted breaths. The patient makes an effort to breathe and the ventilator assists in delivering the breath.

Asthma – a chronic, obstructive, and inflammatory respiratory condition characterized by recurring episodes of dyspnea, wheezing, and chest tightness.

Atelectasis – a term that refers to a collapse in the alveoli of the lungs. It could be a total collapse of an entire lung or a partial collapse in one or more lobes.

Auscultation – a non-invasive procedure for listening to the internal sounds of the body using a stethoscope.

Automatic External Defibrillator (AED) – a portable electronic device that can be used outside of the hospital to detect cardiac arrhythmias and perform defibrillation in order to re-establish a normal heart rhythm.

Auto-PEEP – a complication of mechanical ventilation that occurs when positive pressure remains in the alveoli at the end-exhalation phase of the breathing cycle.

B

Barrel Chest – a term used to describe a patient with an increased anterior-posterior diameter of the chest wall that is often seen in patients with emphysema.

Base Excess (BE) – a value obtained during an Arterial Blood Gas (ABG) analysis that refers to the difference between the normal and actual buffer base in a sample of blood.

Beta-2 Agonist – a type of medication that is administered for the treatment of acute bronchospasm and works by causing relaxation of smooth muscle tissue in the airways.

Bicarbonate (HCO3-) – a byproduct of the body’s metabolism that represents the total carbon dioxide content that is transported in the blood. Once it reaches the lungs, it can be exhaled as carbon dioxide.

Bilevel Positive Airway Pressure (BiPAP) – a form of noninvasive ventilation that distributes two levels of pressure in order to provide ventilatory support and help avoid invasive mechanical ventilation.

Biot Respirations – a breathing pattern characterized by deep breaths that alternate with irregular periods of apnea. It often results from damage to the medulla or pons in the brain.

Body Plethysmography – a pulmonary function test that measures the amount of air that is inhaled and the amount of air that remains in the lungs after exhalation.

Bourdon Gauge – a flow meter device that uses a fixed orifice and operates under variable pressures that can be adjusted with a pressure-reducing valve.

Bradycardia – an abnormally decreased heart rate of fewer than 60 beats per minute.

Bradypnea – an abnormal breathing pattern characterized by a respiratory rate that is less than 12 breaths per minute.

Breath Sounds – the sounds that come from the lungs during inhalation and exhalation that can be heard during auscultation. An abnormality in breath sounds is an indication of other health issues.

Breathing Pattern – the ventilatory pattern by a patient over a period of time that accounts for the respiratory rate and amount of air that is cycled.

Bronchiectasis – an obstructive condition that causes irreversible destruction of the bronchial walls of the airways of the lungs that results in an accumulation of copious amounts of bronchial secretions.

Bronchoalveolar Lavage (BAL) – a diagnostic technique that uses a bronchoscope and saline solution to collect specimens from the lower respiratory tract for testing.

Bronchoconstriction – an abnormal contraction of the smooth muscle tissue in the airways of the lungs that results in narrowing and difficulty breathing.

Bronchodilator – a type of medication that relaxes smooth muscle tissue in the airways of the lungs to relieve constriction, increase airflow, and make breathing easier

Bronchoprovocation Study – a test that uses methacholine, a cholinergic drug, to access airway hyperresponsiveness in order to diagnose a patient with asthma.

Bronchopulmonary Dysplasia (BPD) – a chronic respiratory disorder in premature and low birth weight infants characterized by a reduction in the overall surface area for gas exchange.

Bronchoscopy – an endoscopic procedure that involves passing a bronchoscope into the airways of the lungs for diagnostic and therapeutic purposes.

C

Capillaries – the smallest blood vessels in the body that form a connection between arterioles and venules, and allow the exchange of blood, nutrients, and waste.

Capnography – a process of measuring and monitoring the amount of carbon dioxide in exhaled air.

Carbon Monoxide Poisoning – the exposure and inhalation of excessive carbon dioxide gas which accumulates in the blood and can cause serious tissue damage.

Carboxyhemoglobin – a compound that refers to the chemical combination of hemoglobin and carbon monoxide.

Cardiac Output – a measurement of the volume of blood that is pumped by the heart per minute.

Cardiac Tamponade – a medical condition characterized by the accumulation of blood, fluid, or gas in the pericardial sac of the heart.

Cardiogenic Pulmonary Edema – a type of pulmonary edema that is caused by increased pressures in the heart and is associated with congestive heart failure.

Cardiopulmonary Rehabilitation – an organized program that is designed to improve the status of patients with conditions of the heart and lungs with a goal to improve their overall quality of life.

Cardiopulmonary Resuscitation (CPR) – an emergency medical procedure for life support that involves repeated chest compressions and artificial ventilation in an effort to restore spontaneous breathing and blood circulation in a patient who is in cardiac or respiratory arrest.

Cardioversion – a medical procedure that uses an electrical shock to restore an abnormal heart rhythm back to normal.

Carina – the bifurcation of the trachea that separates into the right and left mainstem bronchi.

Central Sleep Apnea – a disorder characterized by the absence of breathing while asleep that is caused by a medullary depression that inhibits an inspiratory effort.

Chest Physical Therapy (CPT) – a form of therapy that is designed to help clear secretions, improve ventilation, and strengthen the respiratory muscles of breathing.

Chest Radiograph – a radiographic imaging technique used for the assessment of the heart, lungs, and structures within the thoracic cavity.

Chest Trauma – any type of trauma or injury to the chest wall.

Cheyne-Stokes Respiration – an abnormal breathing pattern characterized by gradual periods of deep and shallow breaths with a period of apnea.

Chronic Bronchitis – a type of COPD that is characterized by increased mucus production in the trachea and bronchi that results in a productive cough that occurs for at least three months of the year for more than two consecutive years.

Cilia – microscopic hairlike structures that line the cells within the airways of the lungs that help mobilize mucus and secretions.

Committee on Accreditation for Respiratory Care (CoARC) – an accrediting committee that establishes education standards and oversees the approval of respiratory care programs.

Complete Blood Count – a group of medical laboratory tests for screening and diagnostic purposes that analyzes the counts of red blood cells, white blood cells, and platelets, as well as the concentration of hemoglobin and hematocrit.

Computed Tomography (CT) – a radiographic imaging technique that generates cross-sectional images of an organ or tissue structure.

Congenital Cardiac Defect – a condition of the heart that develops before an infant is born.

Congenital Diaphragmatic Hernia – a developmental birth defect characterized by a hole in the diaphragm of a fetus that results in severe respiratory distress.

Congestive Heart Failure (CHF) – a chronic condition that affects the ability of the heart to pump blood adequately and often results in pulmonary edema.

Contact Precautions – safety measures used to reduce the risk of transmitting infectious diseases and microorganisms that can be spread by direct or indirect contact.

Continuous Positive Airway Pressure (CPAP) – a mode of ventilatory support in which a continuous pressure that is above atmospheric pressure is maintained throughout the breathing cycle.

Control Mode Ventilation (CMV) – a mode of mechanical ventilation where the machine delivers a preset tidal volume at a set time-triggered frequency.

COPD – an abbreviation that stands for chronic obstructive pulmonary disease; it’s a chronic disease that causes progressive airway obstruction that results in breathing-related problems.

Cor Pulmonale – a condition that causes failure of the right ventricle and often results from pulmonary hypertension.

Coronary Artery Bypass Graft (CABG) – a surgical procedure that aims to improve blood flow to the heart and is often performed on patients with coronary artery disease.

Coronary Artery Disease – a disease that develops when there is narrowing or a blockage of the coronary arteries. It is usually caused by plaque build-up that results in decreased blood flow to the heart.

Crackles – also known as rales, are abnormal sounds that are heard as air moves through secretions in the small or middle airways of the lungs.

Cricothyrotomy – an emergency surgical procedure where an incision is made through the skin and cricothyroid membrane in order to access the trachea so that ventilation can occur.

Croup – a viral infection of the upper airway that results in subglottic swelling and an obstruction below the vocal cords.

CRT – the abbreviation that stands for certified respiratory therapist.

Cyanosis – an abnormal bluish discoloration of the skin that is an indication of hypoxemia or inadequate oxygenation.

Cystic Fibrosis – a genetic disease that is characterized by abnormally large amounts of thick secretions and pancreatic insufficiency that causes lung infections and difficulty breathing over time.

D

Dead Space – the volume of ventilated air that does not participate in gas exchange.

Dead Space/Tidal Volume Ratio (VD/VT) – a ratio that shows the percentage of each breath that does not participate in gas exchange.

Defibrillation – the act of delivering an electrical shock to the heart for the treatment of a life-threatening cardiac arrhythmia.

Diaphoresis – a medical term characterized by abnormal, excessive sweating.

Diaphragm – a muscle of respiration located below the lungs that continually contracts and assists with ventilation.

Diminished Breath Sounds – a type of lung sounds that are heard (or not heard) when there is decreased air movement in the lungs.

Diuretic Agents – a class of medication that stimulates urine production to promote the excretion of excess water and sodium in patients who are fluid overloaded.

DLCO Test – a pulmonary function test that is performed to assess the extent to which carbon monoxide can diffuse from air into the bloodstream.

Droplet Precautions – safety measures used to reduce the risk of transmitting infectious diseases and microorganisms that can be spread by droplet particles in the air after coughing, sneezing, or talking.

Drug Overdose – when a person takes too much of a medication that is more than the recommended medical dose. The medication could be prescription, over-the-counter, or illegal. It could be intentional or accidental.

Dyspnea – a term that refers to shortness of breath or difficulty breathing as perceived by the patient.

E

Elasticity – a characteristic of a tissue that allows it to return to its original shaped after being stretched.

Electrocardiogram (EKG) – a noninvasive diagnostic procedure that measures the electrical activity of the heart.

Emphysema – an obstructive disease that results in increased lung expansion due to air trapping.

Endotracheal Tube – an artificial airway that is inserted into the trachea as a means to establish a connection for mechanical ventilatory support.

Epiglottis – an acute upper airway infection that causes severe supraglottic swelling.

Erythrocyte – red blood cell.

Expiratory Reserve Volume (ERV) – the total amount of air that can be exhaled after a normal expiration.

Extracorporeal Membrane Oxygenation (ECMO) – a type of extracorporeal life support that involves pumping blood out of the body through a membrane for the gas exchange of oxygen and carbon dioxide.

Extubation – a procedure that involves the removal of an endotracheal tube from the trachea.

F

Fenestrated Tracheostomy Tube – a tracheostomy tube that has an opening above the cuff that allows airflow to pass through so that the patient is able to talk with the airway in place.

Fetal Lung Development – a process in newborns involving multiple developmental phases that lead to the formation of the lungs and alveoli so that gas exchange and breathing can occur.

FEV1 – a measurement of the maximum volume of air that a patient can exhale during the first second of a forced vital capacity maneuver.

FEV1/FVC Ratio – a ratio that reflects a percentage of the amount of forced expiratory volume that can be exhaled in the first second of a forced vital capacity maneuver.

Flail Chest – a traumatic injury where a portion of the rib cage is fractured and becomes detached from the chest wall.

Flexible Bronchoscopy – a procedure that involves the insertion of a flexible bronchoscope into the airways of the lungs for diagnostic and therapeutic purposes.

Flowmeter – a device that measures and controls the flow rate of a medical gas.

Flow Rate – a measurement of a patient’s maximum speed of inspiration or expiration.

Flutter valve – a small, handheld device that uses positive expiratory pressure and vibrations to help clear mucus from the lungs.

Forced Vital Capacity (FVC) – the total volume of air that can be rapidly and forcefully exhaled after a maximum inspiration.

Fraction of Inspired Oxygen (FiO2) – the concentration of oxygen that is being inhaled by a patient.

Functional Residual Capacity (FRC) – the volume of air exhaled after a normal tidal volume breath in addition to the volume remaining in the lungs after maximum expiration.

G

Gas Exchange – the physiological process of diffusion where oxygen moves from the lungs to the bloodstream during inhalation and carbon dioxide moves from the blood to the lungs for removal during exhalation.

Glasgow Coma Scale (GCS) – a scoring system used to classify a patient’s level of consciousness after a brain injury.

Grunting – a noisy, irregular breathing pattern in infants that serves as an indication of respiratory distress.

Guillain-Barré Syndrome – a rapid-onset disease characterized by ascending paralysis in which the patient’s autoimmune system attacks and causes inflammation and deterioration of the peripheral nervous system.

H

Head Trauma – a term to describe any injury or surgical procedure that occurs to the head, brain, or skull.

Heart Rate (HR) – a measurement of the number of heart beats per minute.

Heat and Moisture Exchanger (HME) – a device that provides humidification during mechanical ventilation by recirculating heat and moisture from a patient’s exhaled breath.

Heliox – a medical gas mixture of helium and oxygen that is used to treat patients with a severe airway obstruction.

Hemodynamic Monitoring – the assessment of several physiological parameters within the circulatory system that facilitates the measurement of the vascular pressures inside of the heart and blood vessels.

Hemoglobin – a protein in red blood cells that transports oxygen molecules from the lungs to body tissues.

Hemoptysis – the coughing up of blood from the respiratory tract.

Hemothorax – the accumulation of blood in the pleural cavity that occurs from a traumatic thoracic injury.

High-Flow Nasal Cannula (HFNC) – an oxygen delivery system that can supply heated and humidified oxygen with flows u to 60 L/min.

High-Frequency Chest Wall Compression (HFCW) – a type of airway clearance therapy commonly used in patients with Cystic Fibrosis that uses an inflatable vest to help mobilize secretions. It works by creating oscillations against the patient’s thorax and chest wall.

High-Frequency Oscillatory Ventilation (HFOV) – a type of mechanical ventilation that delivers very small tidal volumes at an extremely fast rate which minimizes the chances of a lung injury.

Hypercapnia – a condition characterized by elevated carbon dioxide levels in the blood.

Hyperpnea – an abnormal breathing pattern characterized by an increased respiratory rate, rhythm, and depth of breathing.

Hypertension – high blood pressure.

Hyperventilation – a respiratory pattern characterized by an increased rate or depth of breathing that results in a decreased PaCO2.

Hypotension – low blood pressure.

Hypoventilation – a respiratory pattern characterized by a decreased rate or depth of breathing that results in an increased PaCO2.

Hypoxemia – a term that refers to low levels of oxygen in arterial blood.

Hypoxia – a term that refers to low levels of oxygen in the tissues of the body.

I

Incentive Spirometry – a type of lung expansion therapy that encourages patients to take slow, deep breaths in order to help avoid atelectasis.

Inhaled Anti-Infective Agents – a class of medications that work to inhibit the spread of infections by eliminating potentially harmful organisms.

Inhaled Corticosteroids – a class of drugs that have anti-inflammatory effects on the airways and are effective for the maintenance of obstructive diseases such as asthma.

Inhaled Nitric Oxide (iNO) – a colorless, odorless gas that causes vascular smooth muscle relaxation which improves blood flow to ventilated alveoli.

Inspiratory Capacity (IC) – the volume of air that can be inhaled in addition to a normal tidal volume breath.

Inspiratory-to-Expiratory Ratio (I:E Ratio) – refers to the ratio of the inspiratory portion compared to the expiratory portion of the breathing cycle.

Inspiratory Reserve Volume (IRV) – the volume of air that can be inhaled after a tidal volume breath.

Intermittent Positive Pressure Breathing (IPPB) – a patient-triggered, pressure-cycled form of noninvasive positive pressure ventilation that can assist with lung expansion.

Interstitial Lung Disease (ILD) – a term that describes any respiratory disorder that causes scarring of the tissues within the lungs.

Intrapulmonary Percussive Ventilation (IPV) – a type of airway clearance therapy that uses a pneumatic machine to deliver small pressurized breaths at a fast rate to help mobilize secretions.

Intubation – the process of inserting a tube into the trachea in order to establish an airway and facilitate breathing support via mechanical ventilation.

Inverse Ratio Ventilation – a mode of mechanical ventilation that uses an inverse I:E ratio to improve oxygenation and gas exchange.

Iron Lung – a negative pressure ventilator that was invented in the 1920s that was primarily used to treat patients with polio.

J

Joint Commission – a nonprofit organization that is responsible for the accreditation and certification of hospitals and healthcare organizations in the United States.

Jugular Venous Distention – the abnormal bulging of the jugular veins in a patient’s neck that is often a sign of heart failure.

K

Kerley B Lines – the thin lines that can be seen on a chest x-ray near the pleural edge of the lungs that are caused by increased pulmonary capillary pressures.

Kussmaul Respiration – an abnormal breathing pattern characterized by an increased respiratory rate and depth of breathing with an irregular rhythm.

Kyphoscoliosis – a condition characterized by an abnormal curvature of the sagittal and coronal planes of the spine.

L

Larynx – an organ in the anterior neck that helps produce sound and protects the vocal cords and trachea.

Leukocyte – white blood cell.

Lung Cancer – a type of cancer that forms in the tissues of the lungs that most often occurs in those who smoke tobacco-related products.

Lung Compliance – a measurement of the lung’s ability to expand.

Lung Consolidation – a term that refers to an area of the lungs that is filled with liquid instead of air.

M

Magnetic Resonance Imaging (MRI) – an imaging technique that uses magnetic fields and radio waves to generate detailed images of organs and body tissues.

Mallampati Score – a test that is used to inspect the upper airway in order to predict the ease of endotracheal intubation.

Mandatory Breath – a breath in mechanical ventilation that is initiated and controlled by the machine.

Mandatory Minute Ventilation (MMV) – a feature of some ventilators that causes an increase in the mandatory breaths that are delivered when the patient’s spontaneous breathing level becomes inadequate.

Mean Airway Pressure – the average pressure applied to the airway over time during mechanical ventilation.

Mechanical Insufflation-Exsufflation – a type of airway clearance therapy that uses a device to provide alternating positive and negative pressure to give an artificial cough in order to help mobilize and remove secretions.

Mechanical Ventilation – a therapeutic method that uses a machine to provide positive pressure to the lungs of patients who are unable to breathe on their own.

Mechanical Ventilator – a device used to provide positive pressure ventilation in order to facilitate breathing.

Meconium Aspiration Syndrome – a condition in newborns that causes respiratory distress when meconium is aspirated into the lungs.

Metabolic Acidosis – an acidotic condition caused by non-respiratory processes that results in abnormally low bicarbonate levels.

Metabolic Alkalosis – an alkalotic condition caused by non-respiratory processes that results in abnormally high bicarbonate levels.

Methacholine Challenge Test – a test that uses methacholine, a cholinergic drug, to access airway hyperresponsiveness in order to diagnose a patient with asthma.

Methylxanthine – a class of bronchoactive agents used for the long-term control of asthma symptoms.

Minute Ventilation – a measurement of the volume of air that enters or leaves the lungs per minute.

Modified Allen Test – a test that evaluates the adequacy of blood circulation in the radial and ulnar arteries prior to performing an arterial blood gas stick.

Modified Borg Dyspnea Scale (MBS) – a numerical scale from 0 to 10 that is used to measure the severity of dyspnea as perceived by the patient.

Mucolytic Agents – a class of drugs that are administered to help control copious amounts of thick secretions that are common in respiratory diseases such as cystic fibrosis and bronchiectasis.

Mucus Plug – a collection of mucus that results in an occlusion of the airway.

Muscular Dystrophy – a group of genetic diseases that results in progressive muscle weakness and leads to difficulty breathing and the inability to walk.

Myasthenia Gravis – a chronic neuromuscular disease that leads to descending paralysis and muscular weakness in the face, throat, and respiratory system.

Myocardial Infarction – the medical name for a heart attack, which is a life-threatening condition that occurs when blood flow to the heart stops or decreases, causing damage to cardiac tissue.

N

Nasal Flaring – a clinical sign characterized by the widening of nostrils while breathing that is often a sign of respiratory distress.

Nasopharynx – the upper portion of the pharynx behind the nasal cavity that allows breathing through the nose.

National Board for Respiratory Care (NBRC) – a nonprofit organization in the United States that provides and maintains credentials for Respiratory Therapists upon earning a passing score on the certification board examinations.

Nebulizer – an aerosol delivery device that creates particles out of a liquid medication to facilitate absorption in the airways of the lungs.

Neonatal Respiratory Distress Syndrome (NRDS) – a disease common in premature infants with underdeveloped lungs that is associated with decreased surfactant production and severe hypoxemia.

Neuromuscular Blocking Agents – a class of drugs that cause respiratory muscle paralysis by altering the action of postsynaptic acetylcholine receptors.

Newborn Grunting – a clinical sign in infants characterized by expiratory sounds while breathing that is often a sign of respiratory distress.

Noninvasive Positive Pressure Ventilation (NPPV) – a therapeutic method of providing positive pressure to a patient’s lungs without the insertion of an endotracheal tube.

Noninvasive Ventilation – a type of mechanical ventilation performed without the insertion of an endotracheal tube.

Nonsteroidal Anti-Asthma Agents – a type of medication used for the prophylactic management of mild persistent asthma.

Nosocomial Pneumonia – a type of pneumonia that is acquired inside of the hospital more than 48 hours after being admitted.

O

Obstructive Sleep Apnea (OSA) – a disorder characterized by the absence of breathing while asleep that is caused by a blockage of the upper airway.

Oropharynx – the portion of the pharynx behind the oral cavity that allows air, liquid, and food to pass through.

Orthopnea – difficulty breathing while lying down.

Oxygenation – a term that refers to the molecular absorbance of oxygen.

Oxygen Therapy – any type of therapy in which oxygen is delivered to a patient for the treatment of hypoxemia.

P

Paradoxical Breathing – an abnormal respiratory pattern characterized by an inward movement of the chest wall during inhalation followed by an outward movement during exhalation.

Parietal Pleura – the membrane that covers the entire surface of the diaphragm and thoracic cavity.

Patient-Ventilator Asynchrony – the inappropriate timing of delivered breaths between a patient and the mechanical ventilator.

Pediatric Advanced Life Support (PALS) – an advanced form of emergency life support for the treatment of cardiovascular emergencies in pediatric patients.

Penetrating Chest Trauma – a type of chest trauma where there is a singular puncture of the thoracic cavity that most often results from a knife or gunshot wound.

Peripheral Cyanosis – an abnormal bluish discoloration of the skin caused by inadequate oxygenation that can be seen on the patient’s extremities.

Persistent Pulmonary Hypertension of the Newborn (PPHN) – a condition in newborn infants that is characterized by abnormally increased pulmonary hypertension caused by failed circulatory adaptation at birth.

P/F Ratio (PaO2/FiO2) – a value that is used to assess a patient’s oxygenation status and level of hypoxemia that can be calculated by dividing the PaO2 by the FiO2.

Phlegm – a type of mucus that comes from the respiratory tract.

Pin-indexed Safety System (PISS) – a yoke-type connection system for small high-pressure gas cylinders and their attachments that reduces the risk of administering the wrong gas to the wrong patient.

Plateau Pressure – a pressure measurement during mechanical ventilation that is taken during an inspiratory pause at peak inspiration.

Pleural Effusion – a respiratory condition characterized by an abnormal accumulation of fluid in the pleural space.

Pleural Friction Rub – a loud grating lung sound that is heard when inflamed pleura rub together that is caused by decreased fluid in the pleural space.

Pleurisy – a respiratory condition characterized by pain and inflammation in the pleura that usually results from a viral infection.

Pneumonia – an infection that causes inflammation in the lungs and results in fluid build-up, fever, cough, and difficulty breathing.

Pneumothorax – a condition that occurs when air leaks into the pleural space of the thorax that results in a collapsed lung.

Positive End Expiratory Pressure (PEEP) – the positive pressure above atmospheric pressure that remains in the lungs at the end of expiration.

Positive Expiratory Pressure (PEP) – an airway clearance technique where the patient exhales against back-pressure which helps mobilize secretions into the larger airways so that they can be removed via coughing or suctioning.

Positron Emission Tomography (PET) – a test that uses radioactive substances to examine the metabolic activity of various parts of the body.

Postural Drainage – an airway clearance technique that involves positioning the patient in a way that allows gravity and mechanical energy to drain secretions into the central airways to help with removal by coughing or suctioning.

Pressure Controlled Ventilation – a mode of mechanical ventilation in which a specific inspiratory pressure can be set and delivered.

Pressure Support Ventilation (PSV) – a mode of mechanical ventilation in which the patient’s spontaneous breaths are supported by the ventilator during the inspiratory phase of breathing.

Prone Positioning – a body position where the patient lies face down with their back up.

Proportional Assist Ventilation (PAV) – a mode of mechanical ventilation where the machine uses variable pressure to provide pressure support for a patient’s spontaneous breaths.

Pulmonary Edema – a condition in which excessive amounts of fluid collects in the alveoli of the lungs that results in dyspnea and impaired gas exchange.

Pulmonary Embolism (PE) – a condition in which there is a blood clot or blockage in the lungs that can be life-threatening.

Pulmonary Function Testing (PFT) – a set of noninvasive tests used to examine a patient’s respiratory system and identify the severity of pulmonary impairment.

Pulmonary Rehabilitation – a multidisciplinary program for patients with chronic lung diseases that includes breathing techniques, exercise training, and health education.

Pulse Oximetry – a noninvasive technique for monitoring a patient’s oxygen saturation.

Pulsus Paradoxus – an abnormal decrease in blood pressure with each inspiratory effort.

Q

Quality Assurance – a program with policies and standards designed to achieve desirable clinical outcomes and patient satisfaction levels.

Quality Control – a method in healthcare that uses a systematic approach to provide quality care and achieve desirable clinical outcomes.

R

Radiograph – an x-ray image.

Radiolucent – a term that describes objects of an x-ray that appear black because they do not block the passage of radiation.

Radiopaque – a term that describes objects of an x-ray that appear white because they do not allow the passage of radiation.

Rales – also known as crackles, are abnormal sounds heard as air moves through secretions in the small or middle airways of the lungs.

Refractory Hypoxemia – a severe type of hypoxemia where an adequate PaO2 cannot be maintained with an FiO2 greater than 50%.

Residual Volume (RV) – the volume of air remaining in the lungs after a complete exhalation.

Respiratory Acidosis – an acidotic condition caused by hypoventilation.

Respiratory Alkalosis ­– an alkalotic condition caused by hyperventilation.

Respiratory Care Plan – a written description that guides the type and amount of care that a patient will receive.

Respiratory Care Practitioner – a licensed and certified medical professional who provided treatment from patients with cardiopulmonary disorders.

Respiratory Failure – a term characterized by the inability of normal oxygenation or removal of carbon dioxide.

Respiratory Rate – the number of breaths that are taken per minute.

Rhonchi – an abnormal breath sound that can be heard when air moves through the large airways when there is excess mucus or secretions.

Rhonchal Fremitus – coarse vibrations that can be felt by palpitating the chest wall during normal breathing.

Rigid Bronchoscopy – a procedure that involves the insertion of a rigid bronchoscope into the airways of the lungs for therapeutic purposes.

S

Sensitivity –  a ventilator setting that determines how much effort (negative pressure) the patient must generate in order to trigger on a breath from the machine.

Shock – a condition where there is insufficient blood flow to the tissues and vital organs of the body.

Sickle Cell Anemia – a blood condition that causes erythrocytes to break down and lose their shape and oxygen-carrying capacity.

Silverman Score – a test that is used to determine an infant’s level of respiratory distress by assessing their chest movement, intercostal retractions, xiphoid retractions, nasal flaring, and expiratory grunting.

Sinusitis – a condition characterized by inflammation of the mucus membranes that line the paranasal sinuses which results in nasal congestion and facial pain or pressure.

Sleep Apnea – a disorder characterized by repeated episodes without breathing while asleep that last for at least 10 seconds or longer.

Sphygmomanometer – a device that is used to measure the blood pressure of an artery. It uses a cuff that wraps around the arm and a bulb to pump air into the cuff in order to constrict blood flow. As the air is released, the pressure reading is displayed on a manometer and can be heard using a stethoscope.

Spirometer – a diagnostic device that is used in pulmonary function testing to measure the volume and speed of airflow during a breathing cycle.

Spontaneous Breathing Trial (SBT) – a technique used on patients who are receiving mechanical ventilatory support in order to test their readiness for weaning.

Sputum – a type of mucus that has been coughed up from the respiratory tract.

Status Asthmaticus – a severe asthma attack that does not respond to bronchodilator therapy that lasts for more than 24 hours.

Stethoscope – a medical device for that is used during auscultation in order to listen to the sounds of the body.

Stridor – a high-pitched adventitious lung sound that is heard when an upper airway obstruction is present.

Stroke – a condition that occurs when there is a lack of blood supply to the brain.

Stroke Volume – the volume of blood that is pumped out of the left ventricle during each cardiac contraction.

Subcutaneous Emphysema – a condition characterized by the accumulation of air in the subcutaneous layer of the skin that has leaked from the lungs.

Supplemental Oxygen – oxygen delivered for therapeutic purposes that exceeds a concentration of 21%.

Surfactant – a substance that forms a layer over the surface of alveoli in the lungs to reduce surface tension and prevent alveolar collapse.

Surfactant Replacement Therapy – a treatment modality that is often used in preterm infants with surfactant deficiency that involves the deliverance of exogenous surfactant in order to improve alveolar expansion.

Swan-Ganz Catheter – a thin tube that is inserted and positioned in the pulmonary artery to monitor and measure the blood pressure of cardiac and pulmonary circulation.

Synchronous Intermittent Mandatory Ventilation (SIMV) – a mode of ventilatory support in which the ventilator delivers a preset number of mandatory breaths but allows the patient to initiate spontaneous breaths in between the mandatory breaths.

T

Tachycardia – an abnormally increased heart rate of greater than 100 beats per minute.

Tachypnea – an abnormal breathing pattern characterized by a respiratory rate that is greater than 20 breaths per minute.

Tension Pneumothorax – a severe condition that occurs when air leaks into the pleural space and results in a collapsed lung.

Tetanus – a neuromuscular disorder that stems from a bacterial infection that affects the nerves, causes muscle spasms, and can be life-threatening.

Theophylline – a methylxanthine medication that serves as a bronchodilator in patients with asthma and COPD.

Thoracentesis – a procedure that involves the insertion of a large needle into the pleural space to remove fluid or air for therapeutic or diagnostic purposes.

Thorax – the structure that encloses the thoracic cavity, which consists of the ribs, sternum, and vertebral column.

Thorpe Tube – a flow meter device that is attached to a 50-psig gas source that facilitates accurate flow adjustments calibrated in liters per minute.

Tidal Volume – the volume of air that is inhaled and exhaled from during normal breathing.

Total Lung Capacity (TLC) – the volume of air that is inhaled and exhaled in addition to the volume remaining in the lungs after maximum expiration.

Trachea – the cartilaginous tube that connects the larynx to the airways of the lungs so that breathing can occur.

Tracheostomy – a surgical opening in the neck and trachea that provides access for the insertion of an artificial airway.

Tracheostomy Tube – an artificial airway that is surgically placed directly into the trachea through an opening in the throat as a means to establish a connection for breathing or mechanical ventilatory support.

Trigger – a term that refers to how much effort (negative pressure) a patient must generate in order to initiate a breath during mechanical ventilation.

Tuberculosis – a bacterial infection that affects the lungs and is transmitted by the inhalation of infected droplets in the air.

U

Ultrasonic Nebulizer – a type of nebulizer that uses an electrical signal and high-frequency vibrations to break a drug solution into aerosol particles for inhalation.

Ultrasound – an imaging test that uses high-frequency sound waves to create a visual of the organs and structures of the body for assessment.

Upper Airway Stimulation – a technique for treating obstructive sleep apnea that involves the implantation of a device that can monitor breathing patterns and provide stimulation to maintain an open airway.

V

Vagus Nerve – a cranial nerve in the brain that is part of the autonomic nervous system which controls involuntary bodily functions.

Vallecula – an anatomic depression behind the base of the tongue that serves as an important landmark during intubation.

Ventilation – a term that refers to the molecular exchange of oxygen and carbon dioxide in the body. Carbon dioxide is transported through veins to the lungs where it can be exhaled.

Ventilation/Perfusion (V/Q) Ratio – a ratio that refers to the amount of air that reaches the alveoli per minute compared to the amount of blood that reaches the alveoli per minute.

Ventilator Alarms – a safety mechanism on a mechanical ventilator that uses set parameters to provide alerts whenever there is a potential problem related to the patient-ventilator interaction.

Ventilator-Associated Pneumonia (VAP) – a lung infection that develops 48 hours or more after a patient has been intubated and placed on the ventilator.

Ventilator-Induced Lung Injury (VILI) – an acute lung injury that occurs while a patient is receiving mechanical ventilatory support.

Ventilator Mode – a way of describing how a mechanical ventilator assists a patient with inspiration. The characteristics of a particular mode essentially control how the ventilator functions.

Ventilator Settings – the controls on a mechanical ventilator that can be set or adjusted in order to determine the amount of support that is delivered to the patient.

Ventricular Fibrillation – a life-threatening cardiac arrhythmia that results in a rapid heart rate due to erratic quivering of the muscles of the ventricles.

Ventricular Tachycardia – a cardiac arrhythmia that results in an abnormally fast heart rate due to improper electrical activity in the ventricles.

Vesicular Breath Sounds – a term that refers to the normal breath sounds that you would expect to hear as air flows through an open airway.

Vital Capacity (VC) – the volume of air that can be exhaled after a maximum inhalation.

Volume-Controlled Ventilation – a mode of mechanical ventilation in which a specific tidal volume can be set and delivered.

Volume Support – a mode of mechanical ventilation in which the ventilator delivers a supported breath to help the patient reach a set tidal volume. This mode is commonly used to wean patients from anesthesia.

V/Q Scan – an imaging test that uses a radiographic substance to assess the ventilation and perfusion of the lungs. It’s typically indicated to check for a pulmonary embolism.

W

Water Vapor Pressure – the pressure at which water is in equilibrium with its gaseous state.

Wet Drowning – a type of drowning that occurs due to the inhalation of a large amount of water into the lungs.

Wheezes – high-pitched abnormal breath sounds that are heard as air flows through a narrowed airway.

Winters’ Formula – an equation used to calculate a patient’s expected PaCO2 and evaluate respiratory compensation in response to metabolic acidosis.

Work Of Breathing (WOB) – the energy and force that is required in order to inhale a volume of gas into the lungs.

X

Xiphoid Process – the section of the lower end of the sternum that sits just above the diaphragm.

Xopenex – an inhaled short-acting Beta-2 agonist bronchodilator that is administered to provide relief for acute reversible airflow obstructions as seen in patients with asthma or COPD.

Y

Yankauer – an oral catheter made of hard plastic with an angled head that is designed for suctioning the mouth and throat.

Y-connector – an adapter in the circuit of a mechanical ventilator that connects the inspiratory and expiratory limbs together

Z

Zafirlukast – an orally administered antileukotriene agent that is used for the treatment of chronic asthma and is effective in inhibiting episodes that are caused by certain triggers.

Zone Valve – a valve that controls the medical gas distribution of the central piping system to a specific zone of the hospital that typically contains an on/off switch for oxygen, air, and vacuum.