Department of Emergency Medicine, Chonnam National University Hospital, Donggu, Gwangju, Republic of Korea.
Clin Toxicol (Phila). 2012 Nov;50(9):858-61. doi: 10.3109/15563650.2012.720987. Epub 2012 Sep 11.
Fenpyroximate is a potent inhibitor of the mitochondrial proton-translocating NADH-quinone oxidoreductase (complex I). Although it is widely used as an acaricide, data on the acute toxicity of fenpyroximate in humans are very limited.
A 44-year-old woman was brought to our hospital with a reduced level of consciousness, hypotension, and severe lactic acidosis after deliberate ingestion of 5% fenpyroximate solution. The acidosis progressively deteriorated despite maximal supportive treatment, and cardiac arrest refractory to standard cardiopulmonary resuscitation developed. The patient was successfully resuscitated with percutaneous cardiopulmonary support, therapeutic hypothermia, and intravenous acetylcysteine. Blood gases of simultaneously obtained arterial and central venous blood revealed decreased arteriovenous oxygen difference.
The present case, along with previous cases of fatal complex I inhibitor poisoning, indicates that impaired oxygen utilization at the tissue level is the major mechanism underlying the fatality of this condition. Percutaneous cardiopulmonary support may help restore vital organ perfusion by increasing oxygen delivery even in the presence of decreased oxygen consumption, thereby allowing additional time for recovery and drug metabolism. Therapeutic hypothermia also may be beneficial in treating severe complex I inhibitor poisoning, since hypothermia itself attenuates oxidative processes and decreases the metabolic rate.
苯氧威是一种强效的线粒体质子转移 NADH-醌氧化还原酶（复合物 I）抑制剂。尽管它被广泛用作杀螨剂，但关于苯氧威在人类中的急性毒性的数据非常有限。
一名 44 岁女性因故意摄入 5%苯氧威溶液后出现意识水平降低、低血压和严重乳酸性酸中毒而被送往我院。尽管进行了最大程度的支持治疗，但酸中毒仍逐渐恶化，并出现标准心肺复苏无效的心脏骤停。患者经皮心肺支持、治疗性低温和静脉内乙酰半胱氨酸成功复苏。同时获得的动脉和中心静脉血气显示动静脉氧差降低。
本病例以及之前的致死性复合物 I 抑制剂中毒病例表明，组织水平的氧利用受损是该疾病致死的主要机制。即使氧消耗减少，经皮心肺支持也可以通过增加氧输送来帮助恢复重要器官灌注，从而为恢复和药物代谢提供更多时间。治疗性低温对严重的复合物 I 抑制剂中毒也可能有益，因为低温本身可以减轻氧化过程并降低代谢率。
