Wallace W
Alaska Med. 1998 Apr-Jun;40(2):33-5.
Carbon monoxide (CO) poisoning is difficult to confirm in small rural hospitals that lack easy access to a cooximeter. A small hand held device can be used to assess exhaled CO (ECO) in parts per million. This device is often used in smoking cessation clinics to confirm that a person has abstained from smoking.
A 47-year-old white male became dizzy and had a near syncopal episode while working on his boat in the local marina. He was brought to the ER and was found to have an exhaled CO level of 180 ppm. The presence carboxyhemoglobin (HbCO) was confirmed later by an independent reference laboratory and the result was 26% HbCO.
The patient's exhaled CO level dropped slower than expected while breathing oxygen delivered by a non-rebreather mask. This could be due to inadequate compliance to oxygen therapy and a fiO2 somewhat less than 1.0. Another limitation of the technique is the calibration gas (50-ppm CO). This concentration may be too low to assess ER patients. Therefore a confirmatory ABG with cooximetry should be obtained if available. Clinicians are cautioned that there is no safe level of HbCO (6). There is a simple formula to convert ECO to HbCO. The use of exhaled CO monitoring may be a promising alternative that is relatively less expensive than cooximetry in the ER setting, but more research is clearly indicated.
在难以获取一氧化碳血氧计的小型乡村医院中，一氧化碳（CO）中毒很难确诊。一种小型手持设备可用于以百万分率评估呼出一氧化碳（ECO）。该设备常用于戒烟诊所，以确认某人已戒烟。
一名47岁白人男性在当地码头修理船只时感到头晕并出现接近晕厥的情况。他被送往急诊室，呼出一氧化碳水平为180 ppm。后来由独立参考实验室确认存在碳氧血红蛋白（HbCO），结果为26% HbCO。
患者通过非重复呼吸面罩吸氧时，呼出一氧化碳水平下降速度比预期慢。这可能是由于对氧疗依从性不足以及吸氧浓度略低于1.0。该技术的另一个局限性是校准气体（50 ppm CO）。此浓度可能过低，无法评估急诊患者。因此，如果可行，应进行带有一氧化碳血氧测定法的确认性动脉血气分析。临床医生需注意，碳氧血红蛋白不存在安全水平（6）。有一个将呼出一氧化碳转换为碳氧血红蛋白的简单公式。在急诊环境中，使用呼出一氧化碳监测可能是一种有前景的替代方法，相对比一氧化碳血氧测定法便宜，但显然需要更多研究。
