Pentobarbital and EEG Burst Suppression in Treatment of Status Epilepticus Refractory to Benzodiazepines and Phenytoin

Abstract

Seven patients with complex partial or secondarily generalized tonic-clonic status epilepticus (SE) refractory to benzodiazepines (BZDs) and phenytoin (PHT) were treated with pentobarbital (PTB) coma with an EEG burst suppression (BSP) pattern. PTB administered by continuous intravenous (i.v.) infusion pump at a loading dose of 6-8 mg/kg in 40-60 min was usually sufficient to produce BSP activity and seizure control. PTB was continued 0-24 h at 1-4 mg/kg/h, adjusted to maintain blood pressure (BP) and BSP. Infusion rate was decreased if systolic BP (SBP) was less than 90 mm Hg. Normal saline fluid challenge was occasionally used to elevate BP, but in no case was it necessary to discontinue PTB infusion or use pressors. Other antiepileptic drugs (AEDs) were maintained at therapeutic levels for chronic seizure protection. Seizures were stopped in all cases. Four patients attained premorbid neurologic status, two patients briefly survived in vegetative states with recurring seizures after PTB withdrawal, and one patient died of asystole after receiving PTB for 7 h. Patients who had poor outcomes had prolonged seizures (16 h to 3 weeks) before institution of PTB anesthesia, and all had significant underlying central nervous system (CNS) pathology. PTB-induced BSP appears to be safe and effective for refractory SE if it is started soon after failure of a BZD and PHT. Ultimate prognosis depends on SE etiology.