The loss or prevention of sensation, as caused by anesthesia (in the above sense), or by a lesion in the nervous system, or by another physical abnormality.
(American spelling, Canadian spelling) An artificial method of preventing sensation, used to eliminate pain without causing loss of vital functions, by the administration of one or more agents which block pain impulses before transmitted to the brain.
A substance administered to reduce the perception of pain or to induce numbness for surgery and may render the recipient unconscious.
Loss of consciousness due to the interruption of breathing and consequent anoxia.
Loss of consciousness due to the body's inability to deliver oxygen to its tissues, either by the breathing of air lacking oxygen or by the inability of the blood to carry oxygen.