Fisher Julia, Graudins Andis
Department of Emergency Medicine, Monash Health, Victoria, Australia,
J Med Toxicol. 2015 Sep;11(3):359-63. doi: 10.1007/s13181-015-0469-9.
Theophylline overdose can result in significant cardiovascular and neurologic toxicity and is potentially fatal. Clearance of theophylline can be enhanced by the administration of multiple-dose activated charcoal (MDAC) and extracorporeal elimination techniques. We report a case of severe theophylline toxicity initially treated with MDAC and intermittent haemodialysis. Subsequent to this, sustained low-efficiency dialysis (SLED) was undertaken. This is a prolonged renal replacement therapy that uses blood and dialysate flow rates between those of intermittent haemodialysis and continuous renal replacement therapy.
A 61-year-old man presented following ingestion of 24 g of theophylline SR (300 mg/kg), 240 mg of diazepam and 2 g of gabapentin. He required intubation and developed a supraventricular tachycardia treated with esmolol, but suffered no seizures. Serum theophylline concentration peaked at 636 μmol/L (55-110) at 9.5 h post-ingestion. Intermittent haemodialysis was performed for 4 h and resulted in a theophylline extraction ratio of 0.57 with elimination half-life of 2.3 h. SLED was subsequently performed on two occasions for 7 h. Theophylline extraction ratio ranged from 0.46 (half-life 5.3 h during the first cycle) to 0.61 (half-life 10.6 h during the second cycle). After cessation of SLED, elimination half-life was 26 h. The patient made an uneventful recovery.
Intermittent haemodialysis is the current recommended extracorporeal technique for enhancing theophylline elimination in the absence of charcoal haemoperfusion. However, SLED produced similar apparent extraction ratios with longer associated elimination half-life for theophylline than for intermittent haemodialysis. SLED is undertaken by intensive care unit (ICU) staff and may be a useful extracorporeal elimination technique in cases where access to intermittent haemodialysis, requiring specialist dialysis nursing staff, is limited or may be delayed.
茶碱过量可导致严重的心血管和神经毒性，甚至可能致命。多剂量活性炭（MDAC）给药和体外清除技术可提高茶碱的清除率。我们报告一例严重茶碱中毒病例，最初采用MDAC和间歇性血液透析治疗。在此之后，进行了持续性低效透析（SLED）。这是一种延长的肾脏替代疗法，其血液和透析液流速介于间歇性血液透析和持续性肾脏替代疗法之间。
一名61岁男性在摄入24克缓释茶碱（300毫克/千克）、240毫克地西泮和2克加巴喷丁后就诊。他需要插管，并出现了用艾司洛尔治疗的室上性心动过速，但未发生癫痫发作。摄入后9.5小时血清茶碱浓度峰值达到636微摩尔/升（55 - 110）。进行了4小时的间歇性血液透析，茶碱清除率为0.57，消除半衰期为2.3小时。随后进行了两次SLED，每次7小时。茶碱清除率范围为0.46（第一个周期半衰期为5.3小时）至0.61（第二个周期半衰期为10.6小时）。停止SLED后，消除半衰期为26小时。患者顺利康复。
在没有血液灌流活性炭的情况下，间歇性血液透析是目前推荐的用于提高茶碱清除率的体外技术。然而，SLED产生的表观清除率与间歇性血液透析相似，但茶碱的相关消除半衰期比间歇性血液透析更长。SLED由重症监护病房（ICU）工作人员进行，在获取间歇性血液透析受限或可能延迟（间歇性血液透析需要专业透析护理人员）的情况下，可能是一种有用的体外清除技术。
