Larson Kelly J, Wittwer Erica D, Nicholson Wayne T, Weingarten Toby N, Price Daniel L, Sprung Juraj
Department of Anesthesiology, Mayo Clinic, Rochester, MN.
Department of Otorhinolaryngology, Mayo Clinic, Rochester, MN.
J Clin Anesth. 2015 May;27(3):247-51. doi: 10.1016/j.jclinane.2014.11.002. Epub 2014 Dec 11.
Serotonin released in the nerve synapses is cleared through reuptake into presynaptic neurons and metabolism with monoamine oxidase (MAO). Therapy with selective serotonin reuptake inhibitors (SSRIs) or MAO inhibitors increases serotonin concentration in the synaptic cleft and may result in serotonin syndrome (SS). Our patient undergoing sentinel lymph node biopsy was on fluoxetine (SSRI) and intraoperatively developed SS after receiving fentanyl (200 μg) and methylene blue (MAO inhibitor), 7 mg subcutaneously into the scalp. Initial presentation was several episodes of generalized muscle activity, which was later diagnosed as lower extremity myoclonus consistent with SS. Upon awakening, the patient showed no evidence of encephalopathy, and the clonus was less intense. The patient was discharge home the next day. Our case suggests the possibility that even a small dose of methylene blue, when administered simultaneously with other serotoninergic medications, may be associated with serotonin toxicity.
神经突触中释放的血清素通过再摄取进入突触前神经元并与单胺氧化酶（MAO）代谢而被清除。使用选择性血清素再摄取抑制剂（SSRI）或MAO抑制剂进行治疗会增加突触间隙中的血清素浓度，并可能导致血清素综合征（SS）。我们这位接受前哨淋巴结活检的患者正在服用氟西汀（一种SSRI），术中在头皮皮下注射7毫克芬太尼（200微克）和亚甲蓝（一种MAO抑制剂）后发生了血清素综合征。最初的表现是几次全身性肌肉活动发作，后来被诊断为与血清素综合征相符的下肢肌阵挛。醒来时，患者没有脑病迹象，阵挛也不那么强烈。患者第二天出院回家。我们的病例表明，即使小剂量的亚甲蓝与其他血清素能药物同时使用，也可能与血清素毒性有关。
