A device used for the artificial ventilation of a person who is unable to breathe naturally. A ventilator is an electrical pump connected to an air supply that works like bellows. Air is directed through a tube passed down the windpipe to inflate the lungs. The air is then expelled by the natural elasticity of the lungs and ribcage. A valve on the ventilator prevents the expelled air from re-entering the lungs.
Machinery used to provide arti?cial ventilation. Also called a respirator or life-support machine, it is an electric pump linked to a supply of air which it pumps into the patient through an endotracheal tube passed through the nose or mouth into the trachea (see ENDOTRACHEAL INTUBATION). Sometimes the air is pumped straight into the trachea through an arti?cial hole called a TRACHEOSTOMY. During ventilation the patient’s blood gases are closely monitored and other bodily activities such as pulse and heart pressure are regularly measured. Some patients need to be kept on a ventilator for several days or even weeks if their medical condition is serious. (See also ARTIFICIAL VENTILATION OF THE LUNGS.)
n. 1. a device to ensure a supply of fresh air. 2. (respirator) equipment that is manually or mechanically operated to maintain a flow of air into and out of the lungs of a patient who is unable to breathe normally. Positive-pressure ventilators blow air into the patient’s lungs; air is released from the lungs when the pressure from the ventilator is relaxed (see BiPAP; Nippy; noninvasive ventilation). Negative-pressure ventilators are airtight containers in which the air pressure is decreased and increased mechanically. This draws air into and out of the patient’s lungs through the normal air passages. The original devices, known colloquially as iron lungs, had a seal around the neck and enclosed the whole body except the head. They have been replaced by cuirass ventilators, which work on a similar principle but enclose the chest only; there may be a role for these in adults and children with claustrophobia.
A life-threatening condition in which the amount of carbon dioxide in the blood rises, and the amount of oxygen falls, due to disruption of the normal exchange of gases between the air in the lungs and the blood. Ventilatory failure may be due to brain damage or to depression of the respiratory centres by excessive doses of drugs such as morphine. Treatment may involve artificial ventilation or, in some cases, the use of respiratory stimulant drugs. (See also respiratory failure.)... ventilatory failure
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