The phases of status epilepticus and management with anticonvulsant drugs are reviewed from the Institute of Neurology, National Hospital, Queen Square, London. In phase I, seizure activity greatly increases cerebral metabolism, but physiological mechanisms, including increased cerebral blood flow and maintenance of glucose supply to the brain, are compensatory. In phase 2, the compensatory mechanisms begin to fail. Cerebral blood flow becomes dependent on systemic blood pressure which falls due to autonomic and cardiorespiratory changes and drug treatment. The high metabolic demands of the epileptic cerebral tissue cannot be met and ischemic or metabolic damage ensues. Drug treatment, administered parenterally, is also divided into stages: 1) and 2) premonitory and early status; diazepam or other lipid-soluble, rapidly-acting, but short-duration anticonvulsant; 3) established status; phenytoin is a drug of first choice, highly effective, and long acting, often administered with diazepam. Phenobarbitone is also a drug of choice, but should not be used in a solution containing other drugs, as precipitation may occur. Numerous second-line treatment options are discussed; 4) refractory status; thiopentone is traditional in Europe; propofol, a non-barbiturate, is widely used but its safety in children has not been established. Reasons for drug treatment failure include inadequate initial dosage and maintenance, undiscovered cause or complication, and misdiagnosis. 
COMMENT. The annual incidence of new cases of tonic clonic status in the USA is estimated at 45,000 -70,000. It occurs in 10 - 25% of children with epilepsy. Mortality is 5 - 10%, and morbidity increases with the duration of the status episode. Successful treatment of this medical emergency depends on the balance of a rapid control of seizures and the avoidance of complications of therapy. (Shorvon SD. Status epilepticus: its clinical features and treatment in children and adults. Cambridge, Cambridge University Press, 1993).
Phenytoin monitoring in status epilepticus in infants and children is reported from the Service de Neuropediatrie, Hopital Saint-Vincent de Paul, Paris, and Hopital du Bocage, Dijon, France . A loading dose of 15 mg/kg was followed by three injections in the first 24 hours. Monitoring with nine plasma samples during the first day allowed for dosage adjustment with increased efficacy and reduced toxicity. Older children responded better than younger children who had lower plasma levels.