Bacteremia
The presence of bacteria in the blood.

Bacteriuria
The presence of bacteria in the urine (100,000 or more organisms per ml).

Barotrauma
The injury inflicted on lung tissue with the use of high pressures during ventilation.   But see, Volutrauma.

Blood Pressure
The force blood exerts on the walls of the blood vessels.  Normal blood pressure is considered to be 120/80 and read in millimeters of mercury.  When the heart contracts, the top number (or systolic reading) is taken; when the heart relaxes, the bottom number (or diastolic reading) is read.  Lower readings than 120/80 are usually nothing to worry about, unless extremely low which would signal a significant threat to life.  If the blood vessels are narrowed, the heart has to work harder to pump the blood through.

Bronchi (pl.). {bronchus (sg.), bronchial (adj.)}
The two tubes into which the trachea divides at its lower end, branching into the lungs.

Bronchial tubes
Subdivisions of the bronchi after they enter the lungs.

Bronchiole {bronchiolar (adj.)}
One of the minute subdivisions of the bronchi which terminate in the alveoli or air sacs of the lungs.

Bronchiolitis {bronchiolitic (adj.)}
Inflammation of the bronchioles, capillary bronchitis.

Bronchiolitis Obliterans Organizing Pneumonia (BOOP)
A chronic scarring and obstruction process involving the lung's small airways. It may become so diffuse, the entire airway may become filled with fibrotic scar tissue. When the small airways are destroyed, the larger airways become dilated and chronically inflamed. It may occur after a bout of pneumonia or with lung transplantation.  For further discussion and information, see http://www.epler.com, which is perhaps the leading website on the Net concerning BOOP.

Bronchitis
Inflammation of the bronchi, may be primary or secondary (to some other precipitating cause(s), acute (short term) or chronic (long term).

Bronchoalveolar lavage (BAL)
Irrigation or washing out of the bronchi and alveoli, resulting in obtaining bronchalveolar lavage fluid (BALF) which assists in removing unwanted mediators, degradation byproducts, and perhaps defective surfactant and proteins substances from the surface and membrane linings (often before surfactant replacement), and the fluid obtained may be used in performing measurements to ascertain the levels of various mediators and substances as a diagnostic tool.

Bronchography {bronchographic (adj.)}
Preparation of an X–ray after introduction of radio–opaque substance into the bronchial tree.

Bronchopleural fistula (BPF)
Bronchopleural fistulas are large air leaks which develop secondary to collapsed lungs.

Bronchopulmonary
Pertaining to the bronchi and the lungs.

Bronchorrhea
An excessive discharge of mucous from the bronchial mucous membrane.

Bronchoscopy
An examination of the internal lining of the bronchi via a type of endoscope called a   bronchoscope, also used for removal of a foreign body and biopsy of tissue.

Bronchospirometer
An instrument for measuring the capacity of one lung.

Bronchotracheal
Pertaining to the bronchi and trachea.