Babacan Arzu
Department of Emergency Service, Ankara Dr Abdurrahman Yurtarslan Oncology Training and Research Hospital, University of Health Sciences, Yenimahalle, Ankara, Turkey.
Toxicol Res (Camb). 2023 Sep 29;12(5):964-969. doi: 10.1093/toxres/tfad090. eCollection 2023 Oct.
Carboxyhemoglobin saturation (SpCO)with pulse CO-oximetry is an alternative method in CO poisoning; however, the correlation of it with blood carboxyhemoglobin level (COHb) is still debated.The study aimed to evaluate the correlation between SpCO and venous COHb level and factors associated with the diagnostic accuracy of SpCO.
SpCO and venous COHb levels of patients with CO poisoning, according to a COHb level was 3%, were evaluated. The sensitivity, specificity, 95% CI (confidence interval), and the cut-off value of SpCO were calculated using ROC analysis at a 10% threshold for COHb. Agreement levels were calculated with Bland-Altman analysis. Risk factors affecting diagnostic accuracy were analyzed using logistic regression analysis.
If the 10% threshold of COHb was accepted as the diagnostic threshold for CO poisoning, the sensitivity and specificity of SpCO were 98.4% and 100% (95% CI: 0.996-1.000) at the 6.85 cut-off point of SpCO. The scatter plot of COHb and SpCO showed a strong positive relationship at values of presentation and discharge (r = .979, p<0.001; r = .969, p<0.001). With a bias of 3.1% for the mean difference between-COHb and SpCO, the limits of agreement from Bland- Altman analysis were -0.7 to 7.1. For the 10% threshold, age and male gender have significantly increased false negativity rates (B = .074, p = 0.010, and B = 0.252, p = 0.011, respectively).
SpCO is a reliable method with high sensitivity and specificity; therefore, a lower cut-off points of SpCO compared to COHb level may be accepted to diagnose and follow-up CO poisoning.
采用脉搏碳氧血红蛋白饱和度仪测定碳氧血红蛋白饱和度（SpCO）是诊断一氧化碳中毒的一种替代方法；然而，其与血液碳氧血红蛋白水平（COHb）之间的相关性仍存在争议。本研究旨在评估SpCO与静脉血COHb水平之间的相关性以及与SpCO诊断准确性相关的因素。
对一氧化碳中毒患者的SpCO和静脉血COHb水平进行评估，根据COHb水平分为3%的组。使用ROC分析在COHb阈值为10%时计算SpCO的敏感性、特异性、95%置信区间（CI）和截断值。采用Bland-Altman分析计算一致性水平。使用逻辑回归分析影响诊断准确性的危险因素。
如果将COHb的10%阈值作为一氧化碳中毒的诊断阈值，在SpCO截断点为6.85时，SpCO的敏感性和特异性分别为98.4%和100%（95%CI：0.996-1.000）。COHb与SpCO的散点图在就诊和出院时的值显示出强正相关（r = 0.979，p<0.001；r = 0.969，p<0.001）。COHb与SpCO平均差异的偏差为3.1%，Bland-Altman分析的一致性界限为-0.7至7.1。对于10%的阈值，年龄和男性性别显著增加假阴性率（B分别为0.074，p = 0.010和B = 0.252，p = 0.011）。
SpCO是一种具有高敏感性和特异性的可靠方法；因此，与COHb水平相比，较低的SpCO截断点可用于诊断和随访一氧化碳中毒。
