Yeh J S, Dhir J S, Green A L, Bodiwala D, Brydon H L
Department of Neurosurgery, University Hospital of North Staffordshire, Stoke-on-Trent, UK.
Br J Neurosurg. 2006 Dec;20(6):403-6. doi: 10.1080/02688690601101440.
Phenytoin is often used to prevent postcraniotomy seizures, but is not always effective. We investigate changes in plasma phenytoin level ([phenytoin]) following craniotomy. The [phenytoin] in 28 patients who were receiving phenytoin (oral/ intravenous) and undergoing a craniotomy were prospectively measured 24 h preoperatively, immediately pre- and postcraniotomy, 24 and 48 h postoperatively. Factors examined included patients' age, sex, pathology, preoperative [phenytoin], operative duration and blood loss. Fifteen patients had [phenytoin] concentrations outside the therapeutic range. Twenty-five patients experienced a decrease in [phenytoin] immediately postcraniotomy: pre-, post- and 24 h postcraniotomy mean [phenytoin] were 13.4, 10.0 and 12.9 mg/l, respectively. Preoperative [phenytoin], operative duration and blood loss had significant correlation with the decrease in [phenytoin] (p < 0.05). In conclusion, < 50% of the patients had therapeutic preoperative [phenytoin]. In most patients, [phenytoin] decreases by 26% after craniotomy and returns to preoperative level within 24 h. These may contribute to early postoperative seizure development.
苯妥英钠常用于预防开颅术后癫痫发作，但并非总是有效。我们研究了开颅术后血浆苯妥英钠水平（[苯妥英]）的变化。对28例正在接受苯妥英钠（口服/静脉注射）且行开颅手术的患者，在术前24小时、开颅手术即刻前后以及术后24小时和48小时前瞻性地测量其[苯妥英]。所检查的因素包括患者的年龄、性别、病理、术前[苯妥英]、手术持续时间和失血量。15例患者的[苯妥英]浓度超出治疗范围。25例患者在开颅术后即刻[苯妥英]下降：开颅术前、术后及术后24小时的平均[苯妥英]分别为13.4、10.0和12.9mg/L。术前[苯妥英]、手术持续时间和失血量与[苯妥英]的下降有显著相关性（p<0.05）。总之，<50%的患者术前[苯妥英]处于治疗水平。在大多数患者中，开颅术后[苯妥英]下降26%，并在24小时内恢复到术前水平。这些可能导致术后早期癫痫发作。
