Memorial Cardiac & Vascular Institute, Memorial Healthcare System, Hollywood, FL, US.
Lab Med. 2024 Jan 6;55(1):50-55. doi: 10.1093/labmed/lmad037.
The aim of this study was to assess the impact of hydroxocobalamin (OHCbl) infusion on arterial blood gas and oximetry values in patients with vasoplegic syndrome.
Blood samples collected from 95 patients receiving OHCbl infusion were assayed using the ABL90 FLEX Plus blood gas analyzer for the concentration of methemoglobin (MetHb), total hemoglobin (tHb), carboxyhemoglobin (COHb), arterial oxygen saturation (SaO2), arterial oxygen partial pressure (PaO2), and arterial carbon dioxide partial pressure (PaCO2). Interference of OHCbl on these variables was evaluated using the measured difference between the preinfusion and postinfusion samples.
Blood MetHb (%) measured after the infusion of OHCbl (5g) were significantly higher than the baseline levels, with a median of 4.8 (IQR, 3.0-6.5) versus 1.0 (IQR, 1.0-1.2) (P < .001). Blood COHb (%) increased from a median of 1.3 (IQR, 1.0-1.8) to 1.7 (IQR, 1.3-2.2) (P < .001) following the OHCbl infusion. No differences were seen in median levels of tHb, PaO2, PaCO2, and SaO2 between pre- and post-OHCbl treatment.
The presence of OHCbl in blood clearly interfered with the oximetry measurements of the hemoglobin component fractions by falsely increasing the levels of MetHb and COHb. Blood levels of MetHb and COHb cannot be reliably determined by the co-oximetry when OHCbl is known or suspected.
本研究旨在评估羟钴胺（OHCbl）输注对血管扩张性综合征患者动脉血气和血氧饱和度值的影响。
对 95 例接受 OHCbl 输注的患者的血液样本进行收集，使用 ABL90 FLEX Plus 血气分析仪检测血液中亚甲蓝（MetHb）、总血红蛋白（tHb）、碳氧血红蛋白（COHb）、动脉血氧饱和度（SaO2）、动脉血氧分压（PaO2）和动脉二氧化碳分压（PaCO2）的浓度。通过测量输注前后样本之间的差异来评估 OHCbl 对这些变量的干扰。
输注 OHCbl（5g）后测量的血液 MetHb（%）明显高于基线水平，中位数为 4.8（IQR，3.0-6.5）比 1.0（IQR，1.0-1.2）（P<0.001）。输注 OHCbl 后，血液 COHb（%）从中位数 1.3（IQR，1.0-1.8）增加至 1.7（IQR，1.3-2.2）（P<0.001）。OHCbl 治疗前后，tHb、PaO2、PaCO2 和 SaO2 的中位数水平无差异。
血液中存在 OHCbl 会明显干扰血红蛋白各组分的血氧饱和度测量，导致 MetHb 和 COHb 水平假性升高。当已知或怀疑存在 OHCbl 时，不能通过协同比色法可靠地确定 MetHb 和 COHb 的血液水平。
