Pancreatitis
Inflammation of the pancreas.

Partial Liquid Ventilation
Ventilation after filling the lungs with a liquid that has some unique properties; very low surface tension, similar to surfactant, a substance that is produced in the lungs and prevents the alveoli from collapsing and sticking together during exhalation.  It also has a high density, oxygen readily diffuses through it, and it may have some anti-inflammatory properties.  For more information, see the article on Partial Liquid Ventilation in the Learn About ARDS Section 1.

Peak inspiratory pressure (PIP)
The maximum pressure being used to inflate the neonate’s lungs during each mechanical breath.

Permissive hypercapnia
Method of ventilation where increased or elevated level of CO₂ in the blood is permitted to exist.

Plyethsmography or Body Box
A five foot box with clear doors that a person sits in to have his or her lung values measured. The person breathes through a mouthpiece and even the part of the lung that can't be exhaled can be calculated.

Pneumothorax
Leakage of air in the pleural cavity from the lungs.

Positive end expiratory pressure (PEEP)
The pressure that the ventilator maintains at the end of expiration to prevent atelectasis.

Post Traumatic Stress Disorder (PTSD)
Most often, PTSD occurs after a serious threat to one's life or the life of a loved one, or following a sudden and traumatic loss, such as of one's home. PTSD has been caused by such varied stressors as violent assault, rape, military combat, tornadoes, earthquakes, airplane crashes, torture, fires, kidnapping or severe car accidents. As some ARDS patients and their family members realize, it can also be caused by a sudden life-threatening illness.

Also, we now know that you don't have to be direct victim of one of these traumas to experience PTSD. Sometimes, family members or friends of victims are so traumatized by witnessing or learning about the stressful event happening to a loved one, that they develop the symptoms as well. 

Click here for more information about PSTD.

Pressure control
Mechanical ventilator control (several types of pressure controls exist) which regulates the pressure of the air used for inflating the lungs.

Pro
Prefix meaning in favor of, supporting (e.g. proinflammatory response means a body response favoring increased or exaggerated inflammatory response).

Prone
Face downwards.  Click here for a list of medical articles/ references on prone positioning.

Pulmonary Fibrosis – a process whereby the lung muscle becomes stiff due to scarring (development of fibrous structures), rather than problems with the airways.  You will not be able to expand your lung and the volume of air that you can hold will decrease.  Because scarring occurs, it acts as a barrier for the oxygen–carbon dioxide exchange.  It is known as a restrictive lung disease, rather than obstructive. There are several causes as well as unknown reasons for its development; generally referred collectively as Interstitial Pulmonary Fibrosis (IPF).  Many times the cause is unknown in which case it is called Idiopathic (from an unknown cause; idiopathic would not be used where the cause is known such as an underlying condition like ARDS) Pulmonary Fibrosis (also IPF), characterized by progressive shortness of breath, "crackles" in both lungs, and a chest x-ray that shows small linear opacities and "honeycombing" at the lung bases.  A biopsy usually shows UIP (usual interstitial pneumonia).  It could begin as a result of an industrial exposure, drugs used to fight cancer, after a bout of pneumonia or from allergic disorders.  See also Interstitial pneumonia(s).  For further information and discussion of IPF, see:

http://www.vh.org/Patients/IntMed/Pulmonary/InterstitiualLungDz/ILD1.html
(Virtual Hospital, Iowa Health Book, Interstitial Lung Diseases);

http://www.epler.com
(Dr. Gary Eppler’s website which covers a range of lung diseases including BOOP, insterstitial pulmonary fibrosis and interstitial pneumonias)

http://www.dailylung.com/Interstitial.html
DailyLung.com’s fact sheet on Interstitial (Idiopathic) Pulmonary Fibrosis)

Pulmonary Function Studies
A measurement of your ability to move air in and out of the lungs. They tell physicians if lung deficiencies exist, even at early stages, what type of defect is present and the degree of involvement. They are also used to follow the progression of the disease. People free of lung problems of the same age, sex and height went through the same testing, these results were averaged and considered "normal." The taller a person is, the more air each lung can hold and the older a person is, the more slack you get! The values that are reported are in percents and represent the percent of the normal that individual reached! Below eighty percent usually will raise the physician's eyebrows.

Pulmonary hypertension
Also called primary pulmonary hypertension, constriction of blood vessels in the lungs with consequent resistance to blood flow which increases pressure in the right ventricle and atrium of the heart.  Cause unknown.  Usually leads to death from congestive heart failure within 2 to 10 years after onset.

Pulmonary interstitial emphysema (PIE)
A form of emphysema caused by the build-up of air between the interstitial pulmonary tissues.

Pulse Oximeter
Is a device that uses a light to estimate the oxygen saturation of your arterial blood. A sensor that looks like a clothespin is put on the person's finger and a light passes through from one side to the other. The percentage of oxygen and the person's pulse rate are displayed. If the main concern of treatment is to monitor oxygen levels, the pulse oximeter gives a percentage that is not as reliable as one determined by arterial blood gas, but helpful in determining approximate values. The values are dependent on the person's blood flow, and other factors that may affect readings. It doesn't hurt a bit and does not incur the laboratory costs.

Pursed Lip Breathing
One of the most effective tools people with COPD have to use. When a person breathes in through his or her nose, it helps to distribute the air more evenly in the lungs. Instead of passively exhaling, purse the lips, as if ready to kiss, and slowly breathe out. Exhale twice as long as it took to take the breath in. This helps push the air out of the damaged alveoli in emphysema and around the secretions that fill the airway of chronic bronchitis. Inhale for 2 seconds; exhale for 4 seconds; inhale for 3 seconds, exhale for 6 seconds and so on. Remember this technique when becoming short of breath. Many people are afraid to become short of breath and do anything to avoid it (that is, they simply do nothing).   The person is in control if he or she knows pursed lip breathing. A person might go up a flight a stairs a little to fast or walk too quickly to catch a bus. Instead of gasping, breathing in through the nose quickly, pucker up and blow out, again and again until breathing slows down and control is regained. It truly does work! (It will help if to pucker up and blow out as the leg is lifted to climb stairs!)

Pyrexis
Fever, elevated body temperature above normal.

Pyrogen
A substance capable of producing a pyrexia (fever).