现在的位置: 首页临床话题, 模拟诊室>正文
[NEJM读者来信]:摄入防冻液引起的高铁血红蛋白血症
2017年12月07日 临床话题, 模拟诊室 暂无评论

Methemoglobinemia Due to Antifreeze Ingestion

Andrew N. Farkas, Anthony Scoccimarro, Anthony F. Pizon

N Engl J Med 2017; 377: 1993-1994

To the Editor: Ingestion of antifreeze that contains ethylene glycol produces acidosis, nephropathy, coma, and cardiovascular collapse.1 Previously, minimal increases in methemoglobin levels (to as high as 6%; normal value, < 1.0% or < 1.5%, depending on the assay) after ingestion of antifreeze have been reported,2 with no known cause. We report a case of antifreeze ingestion that resulted in clinically significant methemoglobinemia caused by an identified agent.

致编辑:摄入含有乙二醇的防冻液可以导致酸中毒、肾病、昏迷和心血管功能衰竭。根据既往报道,摄入防冻液后高铁血红蛋白水平仅有轻度升高(不超过6%;根据化验方法不同,正常值< 1.0%或< 1.5%),且原因不明。在此,我们报告一例患者摄入防冻液后出现病因明确的明显高铁血红蛋白血症。

Our patient, a 62-year-old man with a history of depression, presented to an emergency department 5 hours after ingesting antifreeze (Fleet Charge SCA Precharged Coolant/Antifreeze [Peak]). The bottle was recovered by paramedics. He had an arterial pH of 7.14 (normal range, 7.35 to 7.45), a serum bicarbonate level of 11 mmol per liter (normal range, 22 to 28), an osmolar gap of 167 mOsm per kilogram (normal value, <10), an anion gap of 17 mmol per liter (normal range, 3 to 11), and obtundation requiring intubation and mechanical ventilation. He was initially treated with intravenous sodium bicarbonate and fomepizole. Despite receiving mechanical ventilation, the patient had persistent pulse oximetry readings of 88% with the ventilator set to a fraction of inspired oxygen of 100% and a positive end-expiratory pressure of 15 cm of water. When his venous blood appeared brown in color despite an arterial partial pressure of oxygen of 502 mm Hg, the patient’s methemoglobin level was tested and found to be 32.2%. The methemoglobinemia was successfully treated with methylene blue, and hemodialysis resolved the ethylene glycol poisoning with a favorable outcome.

患者为62岁男性,既往抑郁病史。患者因摄入防冻液后5小时到急诊就诊。医疗辅助人员找到了防冻液的瓶子。患者动脉pH 7.14(正常范围7.35-7.45),血清碳酸氢钠水平11 mmolL(正常值22-28),渗透压间隙167 mOsm/kg(正常值< 10),阴离子间隙17 mmol/L(正常范围3-11)。同时,患者意识模糊,需要气管插管及机械通气。初始治疗包括静脉输注碳酸氢钠和甲吡唑。尽管接受机械通气,患者的SpO2仍持续为88%(吸入氧浓度100%,PEEP 15 cmH2O)静脉血为褐色,此时动脉血氧分压502 mmHg,测定患者高铁血红蛋白水平升高达32.2%。使用亚甲蓝成功治疗高铁血红蛋白血症,同时采用血液透析治疗缓解了乙二醇中毒,患者预后良好。

On the basis of the patient’s history and the results of urine gas chromatography–mass spectroscopy testing, no substance known to cause methemoglobinemia was present. The safety data sheet for the product that the patient ingested indicated a mixture of ethylene glycol (90 to 97%), diethylene glycol, water, and denatonium benzoate. Because only substances that comprise more than 1% of a given product are required by the Occupational Safety and Health Administration Hazard Communication Standard to be reported on the safety data sheet, a manufacturer’s representative was contacted directly for further information. He disclosed the presence of nitrite (0.27%) and nitrate (0.08%) in the product. Nitrites and nitrates are used as anticorrosion agents in antifreeze3 but are not universally included in all formulations, which may explain why methemoglobinemia has not been consistently observed after antifreeze ingestion.

根据患者病史及尿气相色谱—质谱法检查结果,未发现任何能够引起高铁血红蛋白血症的物质。患者摄入的防冻液说明书表明,该防冻液为乙二醇(90-97%)、二甘醇、水和苯甲地钠铵的混合物。由于职业安全及健康管理风险交流标准委员会要求产品说明书中仅报告超过1%含量的物质,因此,我们直接联系了生产商的代表以了解进一步信息。他告诉我们产品还含有亚硝酸盐(0.27%)和硝酸盐(0.08%)。防冻液中加入亚硝酸盐和硝酸盐作为防腐剂,但并非所有防冻液配方中都含有这两种物质,这就解释了为何摄入防冻液后并非所有患者均出现高铁血红蛋白血症。

On the basis of the concentration of ethylene glycol reported to be in the product, the patient’s serum level of ethylene glycol at 5 hours after ingestion (835 mg per deciliter), and the patient’s body weight (64 kg), we estimate that the ingested volume of antifreeze potentially exceeded 400 ml. This would contain the equivalent of 1.8 g of sodium nitrite, a toxic dose given that only 300 mg of medicinal sodium nitrite induces methemoglobinemia in the treatment of cyanide poisoning.4

根据产品中乙二醇浓度,患者摄入防冻液后5小时的血清乙二醇浓度 (835 mg/dl),以及患者体重(64 kg),我们估计摄入量可能超过400 ml。这相当于1.8 g亚硝酸钠,而治疗氰化物中毒时,仅仅使用300 mg亚硝酸钠即可导致高铁血红蛋白血症。

In conclusion, methemoglobinemia should be considered after a massive ingestion of antifreeze. More importantly, clinicians should be aware of the fact that because of the reporting limits allowed by the law, clinically significant poisons may not be listed on safety data sheets.

因此,大量摄入防冻液后应考虑高铁血红蛋白血症的可能。更重要的是,临床医生应当了解到,由于法律许可报告的局限性,产品说明书中可能没有列举重要的毒物。

给我留言

您必须 [ 登录 ] 才能发表留言!

×
腾讯微博