Lithium-pilocarpine neurotoxicity: a potential model of status epilepticus

Convulsive status epilepticus (SE) is clinically defined as prolonged electrical and clinical seizure activity in which the patient does not regain consciousness to a normal alert state between repeated tonic-clonic attacks. The disorder is a neurological emergency associated with a mortality rate of 10-12% and an even greater morbidity. Seizures represent one of the most severe in vivo stimulatory stresses that the brain is exposed to and generalized status epilepticus represents a very severe form of seizures. The International Classification of Seizures has defined this condition as "a condition characterized by an epileptic seizure that is so frequent or so prolonged as to create a fixed and lasting condition". During SE, high-amplitude, high-frequency electrical activity lasting at least 5 min is seen in the EEG. Continuous seizure activity in itself will result in progressive brain injury. The longer the condition of SE, the more difficult it is to control and the more likely it is to result in permanent neuronal damage. Therefore, SE is an emergency situation requiring prompt medical attention if severe permanent brain damage or death is to be prevented. SE often occurs in individuals with a history of seizures, in whom there are neural substrates already predisposed towards supporting seizure activity.