Abstract: Background　Acute carbon monoxide poisoning is a common toxicological event in daily life，or occupation related that can cause multisystem organ dysfunction，which has become a most common emergency encountered in hospital.Neutrophil-to-lymphocyte ratio （NLR） is an integration parameter generated under the state of inflammation and physiological stress.Procalcitonin （PCT） has become one of the indicators for disease evaluation and prognosis after infection.There are many studies on the relationships of NLR and PCT with sepsis，but no studies on the those of NLR and PCT with the prognosis of acute severe carbon monoxide poisoning （ASCOP） with hospital-acquired pneumonia （HAP）．Objective　To investigate the combined prognostic value of NLR and PCT in patients with ASCOP and HAP by evaluating the correlations of them with APACHEⅡ score in such patients.Methods　 Sixty-eight inpatients with ASCOP and HAP were recruited from Department of Emergency Medicine，Harrison International Peace Hospital Affiliated to Hebei Medical University from 2015 to 2017.Clinical data such as WBC，neutrophil count，lymphocyte count and PCT were collected，NLR was calculated，and APACHEⅡ score was derived based on the worst value of physiologic variables within 24 hours.All of them were given a 28-day follow-up，during which 45 survived （survival group） and 23 died （death group）．ROC analysis was performed to evaluate the prognostic values of NLR and PCT in ASCOP with HAP.Results　The survival group and death group showed no differences in sex ratio，and average age and WBC （P>0.05）．Compared with survival group，the values of average NLR，PCT and APACHEⅡ score in death group were all significantly increased （P<0.05）．The values of NLR and PCT were significantly correlated with APACHEⅡ score （rs=0.611，0.415，P<0.01）．The area under the ROC curve （AUC） of PCT for predicting prognosis was significantly greater than that of NLR {0.804 〔95%CI （0.645，0.930）〕 vs 0.776 〔95%CI （0.621，0.930）〕（Z=2.12，P<0.01）}.When the cut-off value of PCT was 0.155 μg/L，the sensitivity was 92.3%，and the specificity was 70.8%.When the cut-off value of NLR was 8.00，the sensitivity was 90.3%，and the specificity was 54.2%.Conclusion　Both NLR and PCT are significantly correlated with APACHEⅡ score.PCT can be a better indicator for evaluating the prognosis in ASCOP with HAP.

Key words: Carbon monoxide poisoning, Neutrolphil to lymphocyte ratio, Procalcitonin, Hospital acquired pneumonia, Prognosis

摘要： 背景　急性一氧化碳中毒（ACOP）是常见的生活中毒和职业中毒。目前，ACOP已成为急诊科最常见的一种急症，ACOP可导致全身多系统器官损害。中性粒细胞与淋巴细胞比值（NLR）是炎症及生理应激状态下产生的一个整合数据指标，降钙素原（PCT）已成为机体感染后病情评估及预后的指标之一。目前，已有不少关于NLR、PCT与脓毒症关系的研究，但尚未见关于NLR及PCT与重度急性一氧化碳中毒（ASCOP）合并医院获得性肺炎（HAP）关系的研究。目的　探讨ASCOP合并HAP患者NLR、PCT与急性生理学与慢性健康状况评分系统Ⅱ（APACHEⅡ）评分的相关性，比较NLR和PCT对ASCOP合并HAP患者预后的评估价值。方法　选取2015—2017年河北医科大学哈励逊国际和平医院急救医学部住院治疗的ASCOP合并HAP患者68例为研究对象，检测患者白细胞计数（WBC）、中性粒细胞计数、淋巴细胞计数，计算NLR，检测PCT，根据24 h内临床指标最差值计算APACHEⅡ。随访28 d观察病情变化及预后，根据预后情况分为存活组45例和死亡组23例。绘制受试者工作特征（ROC）曲线，评价NLR、PCT对ASCOP合并HAP患者预后的判断价值。结果　存活组与死亡组患者性别、年龄及WBC比较，差异均无统计学意义（P>0.05）；死亡组患者NLR、PCT、APACHEⅡ评分均高于存活组（P<0.05）。NLR、PCT与APACHEⅡ评分均呈正相关（rs=0.611，0.415，P<0.01）。PCT评价预后的ROC曲线下面积（AUC）〔0.804，95%CI（0.645，0.930）〕大于NLR评价预后的AUC〔0.776，95%CI（0.621，0.930）〕（Z=2.12，P<0.01）；当PCT截断值为0.155 μg/L时，灵敏度为92.3%，特异度为70.8%；当NLR截断值为8.00时，灵敏度为90.3%，特异度为54.2%。结论　NLR与PCT均与APACHEⅡ评分具有明显相关性，与NLR相比，PCT能更好地反映ASCOP合并HAP患者的预后情况。

关键词: 一氧化碳中毒, 中性粒细胞与淋巴细胞比值, 降钙素原, 医院获得性肺炎, 预后