入院3小时内血乳酸值对中重型创伤性脑损伤患儿死亡的预测价值

The predictive value of lactate level on the mortality in children with moderate to severe traumatic brain injury within 3 hours after admission

目的 探讨入院3 h内血乳酸值对中重型创伤性脑损伤（TBI）患儿死亡的预测价值。方法 回顾性纳入2011年5月至2014年5月在重庆医科大学附属儿童医院重症医学科治疗的中重型TBI[入院Glasgow昏迷评分（GCS）≤13分]患儿,根据预后分为死亡组和存活组,截取年龄、性别、体重和入院3 h内实验室指标（血乳酸、血钾、血钠、PLT计数、D-二聚体）和血压等指标,行两组间的单因素和多因素分析;对入院3 h内血乳酸水平行受试者特征曲线（ROC）分析,考察血乳酸预测死亡的最佳界值及其敏感度和特异度。结果 109例患儿纳入分析,存活组92例,死亡组17例。死亡组入院3 h内中位血乳酸值（4.9 vs 0.8 mmol·L^-1）、合并其他脏器损伤率（76.5%vs 42.4%）、入院时GCS评分≤8（94.1%vs45.7%）和低血压（76.5%vs 7.6%）发生率显著高于存活组,死亡组血钾水平低于存活组[（3.4±0.5）vs（3.7±0.6）mmol·L^-1,P=0.047）]。ROC曲线分析显示,曲线下面积为0.949（95%CI：0.889~0.982,P〈0.001）,血乳酸界值为2.5mmol·L^-1预测死亡的敏感度为88.2%,特异度为90.2%。多因素Logistic回归分析发现入院3 h内血乳酸（OR=1.579,95%CI：1.129~2.209,P=0.008）、入院时低血压（OR=21.658,95%CI：2.673~175.480,P=0.004）是中重型TBI患儿死亡的独立危险因素;入院时GCS≤8分,合并其他脏器损伤和血钾水平与死亡关联无统计学意义。结论 入院3 h内血乳酸水平可以预测中重型TBI患儿预后,且是其死亡的独立危险因素。

Objective To explore the predictive value of lactate level on the mortality in children with moderate to severe traumatic brain injury（ TBI）within 3 hours after admission. Methods The retrospective study was conducted in Critical Care Medicine,Children′s Hospital of Chongqing Medical University from May 2011 to May 2014 including patients with moderate to severe TBI[ admission Glasgow Coma Scale（ GCS ）≤13 ]. The included patients were divided into death group and survival group. The clinical data regarding age,gender,body weight and laboratory index within 3 h after admission（ serum lactic acid, potassium,sodium,PLT count,D-Dimer）were collected to perform univariate and multivariate analysis between death and survival groups. The receiver operating characteristic curve of serum lactic acid was used to dertermine the optimal cut-off value,and the corresponding sensitivity and specificity were calculated. Results A total of 109 patients were enrolled,including 92 survivals and 17 deaths. The median lactate level,combined other organ injury ratio,the incidence of admission GCS≤8 and hypotension on admission of death group were higher than those of the survival group（4. 9 vs 0. 8 mmol·L^-1,76. 5% vs 42. 4%,94. 1% vs 45. 7%,76. 5% vs 7. 6%;all P≤0. 01 ）. The plasma potassium level of death group was lower than that of survival group [（3. 4 ± 0. 5）vs（3. 7 ± 0. 6）mmol·L^-1 ,P=0. 047）]. The ROC curve showed that lactate level could predict the mortality of pediatric patients with moderate to severe TBI（ AUC =0. 949,95%CI：0. 889 to 0. 982,P 〈 0. 001 ）. The corresponding sensitivity and specificity of lactic acid cut-off value of 2. 5 mmol·L^-1 were 88. 2% and 90. 2%,respectively. Multivariate logistic regression analysis showed that lactic acid level（OR = 1. 579,95%CI：1. 129 to 2. 209）and hypotension within 3 hours after admission（OR=21. 658;95%CI：2. 673 to 175. 480）were the independent risk factors of death in moderate to severe TBI. However,GCS≤8 on admission,other organ injury and plasma potassium level on admission were not the independent risk factors for death in this study. Conclusion The level of admission lactate can predict the death of children with moderate to severe TBI. The elevated admission lactate is also an independent risk factor for the mortality of children with moderate to severe TBI.