血氨在急诊科脓毒症患者预后评估中的作用

目的:探究血氨在急诊科脓毒症患者预后评估中的应用，并与急诊脓毒症病死率评分（mortality in emergency department sepsis，MEDS)进行分析比较。方法:采用回顾性临床研究，纳入2017年6月至2018年5月期间于四川大学华西医院急诊科确诊的、符合2001年美国胸科医师协会／危重病医学会共识会议的诊断标准的脓毒症患者的临床资料，排除伴有其他影响血氨水平的疾病及失访的对象，并收集MEDS评分，电话随访统计患者的生存情况。采用独立样本 t检验比较两组间差异，应用受试者操作特性（ROC）曲线评估脓毒症病死率预测的准确性，使用logistic回归模型探讨血氨与MEDS评分联合应用的价值。 结果:最终纳入80例研究对象，按预后分为1周存活组（ n=52）、1周死亡组（ n=28）；4周存活组（ n=37）、4周死亡组（ n=43）；12周存活组（ n=33）、12周死亡组（ n=47）；1年存活组（ n=32）、1年死亡组（ n=48），组间研究对象的人口特征差异无统计学意义，所有死亡对象的血氨水平均比同期存活的患者更高（116.57±85.33）μmol/L vs （77.64±35.82）μmol/L，（108.53±73.00）μmol/L vs （71.19±32.53）μmol/L，（106.75±71.59）μmol/L vs （69.21±28.84）μmol/L，（105.77±71.14）μmol/L vs （69.50±29.25） μmol/L， P<0.05]；根据1周、4周、12周和1年后的死亡情况得出，血氨的ROC曲线下面积(AUC)分别0.668（95% CI:0.542~0.793, P=0.014）、0.706（95% CI: 0.593~0.819, P=0.002）、0.705（95% CI: 0.592~0.818, P=0.002）、0.697（95% CI:0.582~0.811, P=0.003）；与单独使用血氨、乳酸或MEDS评分相比，血氨与MEDS的联合使用会提高对脓毒症患者预后评估的准确性（ P<0.05）。 结论:血氨用于预测急诊科脓毒症患者的近期和1年预后都具有较高的价值，与MEDS评分的联合使用，可以进一步提高其预测价值。

The role of blood ammonia in the prognosis evaluation of septic patients in the emergency department

Objective:To investigate the role of blood ammonia in the evaluation of the prognosis of septic patients in the emergency department and to compare its value with mortality in emergency department sepsis (MEDS) score.Methods:A retrospective clinical study was conducted to septic patients who were diagnosed in the Emergency Department of West China Hospital of Sichuan University from June 2017 to May 2018, and met the diagnostic criteria established by the diagnostic criteria of the American College of Chest Physicians/Society of Critical Care Medicine in 2001. The subjects who had other diseases that affected blood ammonia level and were lost to follow-up were excluded. MEDS scores were collected, and the survival status of patients was followed up by telephone. The independent samples t test was used to compare the differences between the two groups, receiver operating characteristic (ROC) curve was used to assess the accuracy of the prediction of sepsis mortality, and the logistic regression model was used to explore the value of the combined use of blood ammonia and MEDS score.Results:Eighty subjects were finally included in the study and divided into the 1-week survival group ( n=52), 1-week death group ( n=28); 4-week survival group ( n=37), 4-week death group ( n=43); 12-week survival group ( n=33), 12-week death group ( n=47); 1-year survival group ( n=32), and 1-year death group ( n=48). There was no statistical difference in the demographic characteristics of subjects between the groups. The average blood ammonia level of all the subjects who died was higher than that of the patients who survived in the same period (116.57 ± 85.33) μmol/L vs (77.63 ± 35.82) μmol/L, (108.53 ± 73.00) μmol/L vs (71.19 ± 32.53) μmol/L, (106.74 ± 71.59) μmol/L vs (69.21 ± 28.84) μmol/L, (105.77 ± 71.14) μmol/L vs (69.50 ± 29.25) μmol/L, P<0.05]. Based on death after one week, four weeks, twelve weeks and one year, the area under ROC curve (AUC) of blood ammonia was 0.668 (95% CI: 0.542-0.793, P=0.014), 0.706 (95% CI: 0.593-0.819, P=0.002), 0.705 (95% CI: 0.592-0.818, P=0.002), and 0.697 (95% CI: 0.582-0.811, P=0.003), respectively. Compared with the use of blood ammonia, lactic acid or MEDS score alone, the combined use of blood ammonia and MEDS score increased the accuracy of prognosis evaluation in sepstic patients ( P<0.05). Conclusions:Blood ammonia has a high value in predicting the short-term and 1-year prognosis of septic patients in the emergency department. The combined use of blood ammonia and MEDS score can further improve its predictive value.