Practice of Pentobarbital Therapy in Convulsive Status Epilepticus in Children with Epilepsy
Authors: Sugai Kenji , Sasaki Masayuki , Hanaoka Shigeru , Iwata Hideki , Ogawa Tatsuya , Komaki Hirofumi , Saito Yoshiaki , Takahashi Kazutoshi , Hashimoto Toshiaki 
Published: August 2009

Purpose: We studied the detailed practical procedures and management of the complications of pentobarbital (PTB) therapy for convulsive status epilepticus (C‐SE) in children with epilepsy.

Methods: Eighty‐six episodes of C‐SE in 24 children with epilepsy that could not be abolished by intravenous administration (i.v.) of diazepam (DZP) and phenytoin (PHT) were given i.v. PTB. If C‐SE continued, lidocaine was given i.v. followed by drip infusion (d.i.v.). When C‐SE still continued, d.i.v. PTB was started under continuous EEG monitoring, and the dosages were increased until a burst suppression pattern (BSP) on the EEG, consisting of one burst per 10 s of suppression, or complete EEG suppression (CS) was obtained. The subjects included diagnoses of frontal lobe epilepsy (15 cases). other localization‐related epilepsies (two cases), Lennox‐Gastaut syndrome (four cases), and other symptomatic generalized epilepsies (three cases).

Results: Seventy‐one episodes were terminated with i.v. PTB alone. C‐SE was completely abolished by one or more doses of PTB. 2.5–12.0 (mean, 4.6) mg/kg. during 61 episodes, and incompletely terminated by one or more doses of PTB, 1.5–10.0 (4.5) mg/kg, during 10 episodes. Mild respiratory depression developed during one episode with i.v. PTB, 5.4 mg/kg; however, this seemed to he caused by the previous administration of high doses of DZP, PHT, and phenobarbital (PB). Fifteen episodes required div. PTB. C‐SE was completely abolished by one d.i.v. course in 10 episodes and by two d.i.v. courses in two episodes; however, three episodes in three patients could not be stopped by two to four d.i.v. courses. The initial and maximal d.i.v. dosages were 0.5–2.0 (1.1) mg/kg/h and 0.5–4.0 (2.4) mg/kg/h in the successful cases, and 1.0–3.0 (1.8) mg/kg/h and 2.0–5.0 (3.4) mg/kg/h in the unsuccessful cases. Among 14 trials of d.i.v in 12 successful episodes, attempt of PTB discontinuation started based on BSP for 13–45 (30) h in nine trials, CS for 3348 (40) h in two trials, cessation of C‐SE for 9–17 (13) h in two trials, and hypotension in one trial. Among nine trials of PTB in three unsuccessful episodes, PTB could not be discontinued despite BSP for 17–82 (39) h in four trials and CS for 37–81 (56) h in three trials, and PTB was discontinued owing to poor general condition, administration of prednisolone, and surgical intervention. During PTB discontinuation, 10 of 15 episodes needed supportive therapy including i.v. PHT, DZP, or PTB, intramuscular PB. or rectal DZP or PB. Complications with d.i.v. PTB included respiratory depression requiring mechanical ventilation in 13 of 15 episodes, hypotension treated with vasopressors in 11 of 15, PTB precipitation and occlusion of the d.i.v. line in 10 of 15, markedly increased the C‐reactive protein (CRP) value in 13 of 15, decreased bowel movement or ileus in six of 15, and vasculitis in five of 15. Mechanical ventilation and vasopressors were not required until >1.5 mg/kg/h and >2.0 mg/ kg/h of PTB. PTB precipitation could be prevented by undiluted PTB or >10 times diluted PTB. Central venous line placement or highly diluted PTB solution could prevent vasculitis.

Conclusions: PTB was effective and safe even by i.v., and d.i.v. was not mandatory in the treatment of C‐SE. Tapering of PTB in d.i.v. could be started after 30–40 h of BSP or CS. Mechanical ventilation and vasopressors were not needed until >1.5 mg/kg/h and >2.0 mg/kg/h of PTB. PTB precipitation could be prevented by using >I0 times diluted PTB or undiluted PTB. Caution must be paid to increased CRP, vasculitis, and ileus.