abdomen the part of the body between the pelvis and the thorax.
abdominal splinting a rigid contraction of the muscles of the abdominal wall. It usually occurs as an unconscious reaction to abdominal pain. Abdominal splinting, in turn, may result in hypoventilation and respiratory complications.
acute compartment syndrome usually secondary to trauma; increasing pressure within a fascial compartment as a result of swelling or bleeding can result in nerve damage and necrosis of muscle tissue (avascular necrosis).
acute mountain sickness a syndrome associated with the relatively low concentrations of oxygen in the atmosphere at altitudes encountered during mountain climbing or travel in unpressurized aircraft.
acute stress disorder a condition that develops soon after an individual experiences or witnesses an event involving a threat of or an actual death, serious injury, or physical violation and responds to this event with strong feelings of fear, helplessness, or horror.
adventitious coming from an external source or occurring in an unusual place or manner. During auscultation of the chest or abdomen, adventitious sounds are those that are normally not heard.
agonal respirations a type of breathing that usually follows a pattern of gasping followed by apnea.
airway obstruction an abnormal condition of the respiratory system characterized by a mechanical impediment to the delivery or to the absorption of oxygen in the lungs.
airway patency the condition of an airway being open or unblocked.
alignment the association of long bone fracture fragments to one another; measured in degrees of angulation from the distal fragment in relation to the proximal fragment.
aneroid sphygmomanometer a device using air pressure to measure arterial blood pressure. Aneroid refers to the absence of liquid, in this case the absence of a mercury column in the pressure gauge.
aneurysm a localized weakening and swelling in the wall of a blood vessel. Can be caused by a number of factors, including hypertension, atherosclerosis, trauma, infection, or genetics.
angiogram an x-ray of blood vessels that can be seen because the patient receives an injection of dye to outline the vessels on the x-ray. A coronary angiogram can be used to identify the exact location and severity of coronary artery disease (CAD).
anterograde amnesia the inability to recall events of long ago with normal recall of recent events.
aortic dissection a progressive tear in the aorta. When the inner lining of the aorta tears, blood surges through the tear, creating a new false channel, separating (dissecting) the middle layer from the outer layer of the aorta.
aortic stenosis narrowing of the aortic valve and obstructing blood flow from the left ventricle into the aorta, resulting in decreased cardiac output.
apnea an absence of spontaneous respiration.