通过脉搏血氧仪检测严重高铁血红蛋白血症

一位老年手术患者，在准备清醒气管内插管而进行口咽部苯佐卡因喷雾局部麻醉时，出现了致命的高铁血红蛋白血症。一种新的多波长脉搏血氧仪（Masimo Rad-57）检测到高铁血红蛋白血症，比通过实验室碳氧血氧仪确诊早1小时。Rad-57在诊断以及使用亚甲蓝治疗时监测患者的高铁血红蛋白水平，它提供的数值（高达33％）与实验室碳氧血氧仪测得值十分接近。这种新的脉搏血氧仪可以在床边给出连续的高铁血红蛋白血症水平读数，而实验室数值则推迟长达1小时。该病例证明了这种多波长脉搏血氧仪在致命的血红蛋白障碍血症（高铁血红蛋白血症及碳氧血红蛋白血症）诊断和治疗中的临床应用。

An elderly surgical patient acquired a life-threatening methemoglobinemia as a result of topical benzocaine spray to the oropharynx in preparation for awake endotracheal intubation. A new multiwavelength pulse oximeter, the Masimo Rad-57, detected this methemoglobinemia an hour before it was confirmed by laboratory CO-oximetry. The Rad-57 monitored the patient＇s methemoglobin levels during diagnosis and treatment with methylene blue, and the values it provided （as high as 33%） were very dose to those of the laboratory CO-oximeter. The new pulse oximeter gave continuous readings of methemoglobin level at the bedside, whereas the laboratory values were delayed by up to an hour. This case demonstrates the clinical application of a multiwavelength pulse oximeter in the diagnosis and treatment of a life-threatening dyshemoglobinemia.