Lungs

lung The respiratory organ of air-breathing vertebrates. A pair of lungs is situated in the thorax, within the ribcage. Each consists essentially of a thin moist membrane that is folded to increase its surface area. Exchange of oxygen and carbon dioxide takes place between blood capillaries on one side of the membrane and air on the other. The lung is supplied with air through a bronchus. The lungs are covered by a thin tissue layer called the pleura. The same kind of thin tissue lines the inside of the chest cavity -- also called pleura. A thin layer of fluid acts as a lubricant allowing the lungs to slip smoothly as they expand and contract with each breath.

Status asthmaticus

Acute severe asthma previous referred to as status asthmaticus is an acute exacerbation of asthma that does not respond to standard treatments of bronchodilators and steroids. Symptoms include chest tightness, rapidly progressive dyspnea (shortness of breath), dry cough, use of accessory muscles, labored breathing and extreme wheezing. It is a life-threatening episode of airway obstruction considered a medical emergency. Complications include cardiac and/or respiratory arrest. It is characterized histologically by smooth muscle hypertrophy and basement membrane thickening.