背景： 創傷性腦損傷（traumatic brain injury, TBI）病患於創傷後早期可能會出現癲癇，而使用抗癲癇藥物（antiepileptic drugs, AEDs）和進行藥物濃度監測，可以有效降低早期創傷後癲癇（post-traumatic seizure, PTS）之發生。本研究的目的是了解phenytoin藥物血清濃度與癲癇預防成效之相關性。
方法： 本研究回溯自2004年10月1日至2006年3月31日於本院住院期間，以TBI相關之ICD-9診斷碼收集病患，並且篩選出有使用phenytoin和進行phenytoin藥物血漿中濃度監測之案例，但是排除穿透性腦創傷、需長期使用抗癲癇藥物或有癲癇疾病病史之患者。收集的資料包括：病患基本資料，phenytoin之速效劑量、維持劑量、血漿中藥物濃度數據、是否有癲癇發作和使用phenytoin引起之藥物不良反應。
結果： Phenytoin血漿中濃度和發生癲癇與否無顯著相關性，但發生癲癇與否和phenytoin之血漿中濃度有顯著差異，當phenytoin血漿中濃度大於10μg/ml之病患其癲癇發生率較低，而且發生癲癇組其平均phenytoin之血漿中濃度明顯低於治療濃度。
結論： 這些TBI病患在早期階段，若發生癲癇者其平均phenytoin濃度偏低，故對於這些病患應積極調整phenytoin劑量，並且進行藥物濃度監測，使其維持在有效的治療濃度範圍內，這對於病患的病情控制，將有很大的助益。
Background: Traumatic brain injured patients to develop epilepsy in early post traumatic phase. Since antiepileptic drugs (AEDs) are effective in reducing the risk of early post-traumatic seizure (PTS) , early administration of AEDs and serum concentration monitoring are recommended. The aim of this study is to evaluate the correlation of the effectiveness of prophylactic phenytoin and its serum level.
Methods: We collected patients who were admitted between 1st October 2004 to 31th March 2006 and fitted following three criterion , 1. had been diagnosed as ICD-9 codes of traumatic brain injury, 2. had been received phenytoin for seizure prevention and 3. seurm phenytoin levels had been monitored, were included and the charts were reviewed. Patients with penetration of the skull or brain、chronic treatment for epilepsy and diagnosis of epilepsy were excluded. General demotagraphic data, serum albumin, the loading dose of phenytoin, usage of other AEDs and sedatives, phenytoin serum levels , phenytoin-related side effects and episode of seizure were recorded and analyzed.
Results: The incidence of seizure development during hospitalization was lower in patients whose phenytoin serum levels greater than 10μg/ml.The phenytoin serum levels in patients who didn’t had seizure attack were significant higher than patients who developed seizure.
Conclusion: Incidence of seizure development had lower serum phenytoin level in subtherapeutic range during early post-traumatic brain inury. Routine monitoring and adjust serum level may improve the efficiency of phnytoin utilization and patient safety.
