[Clinical and experimental contribution concerning the pathogenesis of acute life-threatening complications during...

Apart from the usual hazards of local anesthesia (toxic reaction due to overdose or intravasal administration, allergic reaction, reaction to the vasoconstrictor), a further risk which should be borne in mind in local anesthesia of the neck region is inadvertent epidural or intrathecal administration of the local anesthetic agent. Depression of respiration or total respiratory failure may occur due to blockade of the superficially located medullary chemoreceptors in the form of a high or total spinal block. The pathogenesis of these incidents is investigated. Respiratory failure is usually reversible and requires immediate and effective therapy (artificial respiration, oxygen administration). The indications for neck anesthesia and their relativity within the entire therapeutic program should be given careful consideration. If (radicular) pain occurs during the injection, or if cerebrospinal fluid is aspirated, the procedure should be interrupted immediately and some time allowed to elapse. In fatal cases the injection channel must be dissected layer-wise in local anemia down to the dural sac. The possible pathway of toxic administration (epidural, subdural, intravasal) must be demonstrated chemically.