Anesthesia is an artificially induced state of partial or total loss of sensation, occurring with or without loss of consciousness. The purpose of anesthesia is to produce muscle relaxation, block transmission of nerve impulses, suppress reflexes, and cause loss of consciousness. Spinal anesthesia is an example of a regional anesthetic. Regional anesthetics block the pain stimulus at it's origin, along afferent neurons, or along the spinal cord. Regional anesthesia produces a loss of painful sensation in only one region of the body and does not result in unconsciousness or significantly affect heart and lung function.
Spinal anesthesia is achieved by injecting certain local anesthetics into the subarachnoid space.
Autonomic nerve fibers are the first to be affected and the last to recover. Recovery is in reverse order. Within minutes after induction of spinal anesthesia, the client experiences a loss of sensation and paralysis of first the toes, then the feet and legs, and finally, the abdomen. Pain relief may last several hours after surgery without the need for additional pain medicine. Luckmann's core principles and practice of medical-surgical nursing.