乳酸浓度联合乳酸清除率对新生儿脓毒性休克预后的预测价值

Predictive value of lactate concentration combined with lactate clearance rate in the prognosis of neonatal septic shock

目的探讨入院1 h内乳酸浓度联合液体复苏后6 h乳酸清除率(LC)对新生儿脓毒性休克患儿预后的预测价值。方法回顾性研究。选取2016年6月至2020年3月西安交通大学附属儿童医院新生儿重症医学科收治的新生儿脓毒性休克患儿58例为研究对象;以入院60 d内病死为终点事件,根据预后将入组患儿分成死亡组及存活组,统计两组人口学基线资料及血常规、前降钙素原、C反应蛋白、D二聚体、血清肌酐、入院1 h内乳酸浓度(Lac1)及液体复苏后6 h乳酸浓度(Lac2)等临床检验指标。组间比较采用t检验或秩和检验,对影响预后的危险因素进行二元Logistic回归分析;并通过受试者工作特征曲线(ROC)对危险因素的预测性进行检验。各危险因素根据截断值进行分层,通过Kaplan-Meier曲线比较各组预后差异。结果58例患儿中存活组24例、死亡组34例。围生期分析显示,死亡组患儿胎膜早破比率高于存活组[41%(14/34)比13%(3/24),P=0.021];两组患儿在感染部位、病原学特征、液体复苏总量、血管活性药物指数、机械通气、并发症方面差异均有统计学意义(均P<0.05);死亡组患儿Lac1、Lac2、前降钙素原、D二聚体、血清肌酐高于存活组[(12±6)比(7±4)mmol/L,(14±6)比(4±2)mmol/L,(59±23)比(24±14)ng/L,(24±11)比(11±6)mg/L,(167±31)比(92±23)μmol/L,t=3.549、3.112、3.859、4.499、3.288;均P<0.05],死亡组血压、液体复苏后6 h LC低于存活组[(41±12)比(52±5)mmHg(1 mmHg=0.133 kPa),t=4.230;-16(-40,20)%比40(18,70)%,Z=3.558;均P<0.05]。二元Logistic回归分析显示LC与新生儿脓毒性休克死亡风险呈负相关(OR=0.679,95%CI 0.662~0.999,P<0.05);Lac1与新生儿脓毒性休克死亡风险呈正相关(OR=1.203,95%CI 0.965~1.500,P<0.05)。ROC曲线分析LC、Lac1及两者联合均对患儿预后具有预测价值,ROC曲线下面积(AUC)分别为0.699、0.875、0.965,灵敏度分别为83.32%、89.65%、94.31%;特异度分别为72.52%、77.18%、88.76%。危险因素根据截断值分层,Kaplan-Meier分析显示Lac1>4 mmol/L组累积生存率低于Lac1≤4 mmol/L[21%(8/38)比80%(16/20)],差异有统计学意义(χ^(2)=54.520,P<0.05);LC≤10%组累积生存率低于LC>10%组[19%(6/32)比69%(18/26)],差异有统计学意义(χ^(2)=14.140,P<0.05)。结论乳酸浓度联合LC对新生儿脓毒性休克患儿的预后具有良好的预测价值。

Objective To investigate the predictive value of lactate concentration within 1 h after admission combined with lactate clearance rate(LC)at 6 h after fluid resuscitation in prognosis of neonatal septic shock.Methods In this retrospective study,58 newborns with septic shock admitted to the Neonatal Intensive Care Unit of Xi′an Children′s Hospital,Xi′an Jiao Tong University from June 2016 to March 2020 were enrolled.According to the mortality within 60 days after admission,which was also set as the end point,the patients were divided into death group and survival group.The general demographic data and clinical variables including blood cell counts,procalcitonin,C-reactive protein,D-dimer,serum creatinine,and lactate concentration within 1 h after admission(Lac1)and at 6 h after fluid resuscitation(Lac2)were collected.The differences in the clinical variables between the survival and death group were compared by independent sample t test or Rank-Sum test,and the risk factors of poor prognosis were analyzed by binary Logistic regression.The predictive values of these risk factors were tested by receiver operating characteristic(ROC)curve.Furthermore,the cut-off of the risk factors were used to analyze the accumulative survival rate by Kaplan-Meier curve.Results A total of 58 neonates were enrolled,among whom 24 survived and 34 died within 60 days after admission.The rate of premature rupture of membranes in the death group was higher than that in the survival group(41%(14/34)vs.13%(3/24),P=0.021).There were also significant differences in infection site,pathogenic characteristics,total fluid volume of resuscitation,vasoactive drug index,rate and complications of mechanical ventilation between the two groups(all P<0.05).The levels of Lac1,Lac2,procalcitonin,D-dimer and serum creatinine in the death group were higher than those in the survival group((12±6)vs.(7±4)mmol/L,(14±6)vs.(4±2)mmol/L,(59±23)vs.(24±14)ng/L,(24±11)vs.(11±6)mg/L,(167±31)vs.(92±23)μmol/L,t=3.549,3.112,3.859,4.499,3.288,all P<0.05).While the blood pressure and LC at 6 h after fluid resuscitation were lower than those in the survival group((41±12)vs.(52±5)mmHg(1 mmHg=0.133 kPa),t=4.230;-16(-40,20)%vs.40(18,70)%,Z=3.558,all P<0.05).Binary Logistic regression analysis showed that LC was negatively associated with the risk of death in neonates with septic shock(odds ratio(OR)and 95%confidence interval(CI):0.679(0.662-0.999),P<0.05),while Lac1 was the risk factor and positively associated with the risk of death(OR and 95%CI:1.203(0.965-1.500),P<0.05).Furthermore,the predictive values of LC,Lac1 and the combination of these two variables in the prognosis of neonatal septic shock were analyzed by ROC curve analysis,and the area under the curve(AUC)were 0.699,0.875,0.965,respectively,with the sensitivity of 83.32%,89.65%and 94.31%,and the specificity of 72.52%,77.18%and 88.76%,respectively.According to the cut-off value of Lac1,the newborns with Lac1>4 mmol/L had significantly lower accumulative survival rate than those with Lac1≤4 mmol/L by Kaplan-Meier analysis(21%(8/38)vs.80%(16/20),χ^(2)=54.520,P<0.05).According to the cut-off value of LC,the newborns with LC≤10%had significantly lower accumulative survival rate than those with LC>10%by Kaplan-Meier analysis(19%(6/32)vs.69%(18/26),χ^(2)=14.140,P<0.05).Conclusion The combination of lactate concentration and lactate clearance rate have an optimal predictive value in the prognosis of neonatal septic shock.