Glossary of non-invasive ventilation terms

Aerosolization is the process or act of converting some physical substance into the form of particles small and light enough to be carried on the air i.e. into an aerosol. Aerosolization refers to a process of converting and suspending particles or a composition in a moving stream of air. 


Acute respiratory distress syndrome (ARDS) occurs when fluid builds up in the tiny, elastic air sacs (alveoli) in your lungs. The fluid keeps your lungs from filling with enough air, which means less oxygen reaches your bloodstream. This deprives your organs of the oxygen they need to function.


Aspiration or pulmonary aspiration is the entry of material such as pharyngeal secretions, food or drink, or stomach contents from the oropharynx or gastrointestinal tract, into the larynx (voice box) and lower respiratory tract, the portions of the respiratory system from the trachea (windpipe) to the lungs. A person may inhale the material, or it may be delivered into the tracheobronchial tree during positive pressure ventilation. When pulmonary aspiration occurs during eating and drinking, the aspirated material is often colloquially referred to as "going down the wrong pipe.


Asthma is a disease of the airways that results in attacks of breathlessness, as well as coughing and wheezing.


BiPAP (also referred to as BPap) stands for Bilevel Positive Airway Pressure is a type of ventilator—a device that helps with breathing. If you have trouble breathing, a BiPAP machine can help push air into your lungs. You wear a mask or nasal plugs that are connected to the ventilator. The machine supplies pressurized air into your airways. It is called “positive pressure ventilation” because the device helps open your lungs with this air pressure.

Bronchoscopy is when the airways are inspected and sampled using a thin, flexible telescope.

Chronic obstructive pulmonary disease (COPD) is a disease of the lungs where the lungs become inflated, often as a result of tobacco smoke.


Heart failure (HF), also known as congestive heart failure (CHF), (congestive) cardiac failure (CCF), and decompensatio cordis, is when the  heart is unable to pump sufficiently to maintain blood flow to meet the body tissues' needs for metabolism. Signs and symptoms of heart failure commonly include shortness of breath, excessive tiredness, and leg swelling.The shortness of breath is usually worse with exercise or while lying down, and may wake the person at night. A limited ability to exercise is also a common feature. Chest pain, including angina, does not typically occur due to heart failure.

Continuous positive airway pressure (CPAP) is a treatment method for patients who have sleep apnea. CPAP machines use mild air pressure to keep the airways open, and are typically used by patients who have breathing problems during sleep. CPAP therapy helps make sure that your airway doesn't collapse when you breathe while asleep.

Non-invasive ventilation (NIV) is the use of breathing support administered through a face mask, nasal mask, or a helmet. Air, usually with added oxygen, is given through the mask under positive pressure; generally the amount of pressure is alternated depending on whether someone is breathing in or out. It is termed "non-invasive" because it is delivered with a mask that is tightly fitted to the face or around the head, but without a need for tracheal intubation (a tube through the mouth into the windpipe). While there are similarities with regards to the interface, NIV is not the same as continuous positive airway pressure (CPAP), which applies a single level of positive airway pressure throughout the whole respiratory cycle; CPAP does not deliver ventilation but is occasionally used in conditions also treated with NIV.

Non-invasive positive pressure (NIPPV) allows the delivery of positive-pressure ventilation without the use of an endotracheal tube. In place of the tube is a tight-fitting nasal or facial mask that is attached to a continuous positive airway pressure (CPAP) or a bilevel positive airway pressure (BiPAP) machine (as seen below). The positive pressure is beneficial in hypercapnic respiratory failure by decreasing the work of breathing, allowing a larger tidal volume for a given respiratory effort, and hence improving alveolar ventilation.

Non-invasive ventilation negative-pressure ventilation (NPV) lowers the pressure surrounding the thorax, creating subatmospheric pressure which passively expands the chest wall to inflate the lungs. Exhalation occurs with passive recoil of the chest wall. The use of NPV is still indicated in chronic respiratory failure.

Pneumonia is an infection that inflames your lungs' air sacs (alveoli). The air sacs may fill up with fluid or pus, causing symptoms such as a cough, fever, chills and trouble breathing

Respiratory insufficiency or respiratory failure refers to conditions that reduce your body's ability to perform gas exchange, including: Chronic Obstructive Pulmonary Disease (COPD): a progressive lung disease that includes emphysema and chronic bronchitis. Asthma and rare genetic conditions, such as cystic fibrosis, can also lead to COPD.

Sleep apnoea is a  condition in which the muscles at the back of the throat relax when asleep and briefly cause the airway to narrow or block. It often causes snoring, but also may result in daytime tiredness.

Ventilator-associated pneumonia (VAP) is a type of lung infection that occurs in people who are on mechanical ventilation breathing machines in hospitals. As such, VAP typically affects critically ill persons that are in an intensive care unit (ICU) and have been on a mechanical ventilator for at least 48 hours. VAP is a major source of increased illness and death. Persons with VAP have increased lengths of ICU hospitalization and have up to a 20–30% death rate. The diagnosis of VAP varies among hospitals and providers but usually requires a new infiltrate on chest x-ray plus two or more other factors. These factors include temperatures of >38 °C or <36 °C, a white blood cell count of >12 × 10/ml, purulent secretions from the airways in the lung, and/or reduction in gas exchange.