早期血乳酸水平预测特重度烧伤患者急性肾损伤加重的价值

Value of early lactate level in predicting progression of acute kidney injury in patients with extremely severe burns

目的探讨早期血乳酸浓度对特重度烧伤患者早期急性肾损伤(AKI)加重的预测价值。方法采用回顾性病例对照研究分析苏州市六所医院ICU收治的2014年8月2日江苏省昆山市铝粉尘爆炸事故中发生早期AKI的30例特重度烧伤患者[符合AKI分层诊断标准(RIFLE)并于伤后72 h内发生],其中男20例,女10例;年龄20~50岁[(37.1±7.4)岁]。烧伤面积为75%~100%总体表面积(TBSA)[(95.5±4.3)%TBSA]。急性生理与慢性健康评估Ⅱ(APACHEⅡ)评分7~20分[(13.0±2.7)分]。根据患者伤后1周内肾损伤进展情况,将其分为加重组(15例)和未加重组(15例)。比较两组患者入ICU时血白细胞、血小板和血浆白蛋白浓度等一般实验室指标。比较两组患者伤后1周内的治疗干预及30 d病死率情况。对两组患者伤后首次及伤后24,48,72 h的血乳酸、血尿素氮、血肌酐和血肌酸激酶浓度等肾功能相关指标进行比较。绘制早期AKI患者伤后首次血乳酸、血尿素氮、血肌酐和血肌酸激酶浓度的受试者工作特征(ROC)曲线,评估其对特重度烧伤患者早期AKI加重的预测效果。结果加重组患者入ICU时的血浆白蛋白浓度显著高于未加重组(P<0.05)。两组患者在入ICU时的白细胞、血小板浓度和伤后1周内应用肾毒性抗生素等方面差异无统计学意义(P>0.05)。加重组烧伤发生24,48 h后血乳酸浓度与伤后首次相比差异无统计学意义(P>0.05),烧伤发生72 h后血乳酸浓度显著低于伤后首次血乳酸浓度(P<0.05)。未加重组烧伤发生24,48,72 h后的血乳酸浓度与伤后首次相比差异无统计学意义(P>0.05)。加重组伤后首次血乳酸浓度显著高于未加重组(P<0.05)。烧伤24,48,72 h后,加重组血乳酸浓度与未加重组患者相比差异无统计学意义(P>0.05)。加重组患者伤后首次血尿素氮浓度显著高于未加重组(P<0.05),其伤后首次血肌酐和血肌酸激酶浓度间差异无统计学意义(P>0.05)。烧伤发生24,48,72 h后,加重组患者的血肌酐和血尿素氮浓度均显著高于未加重组(P<0.05),两组患者血肌酸激酶浓度间差异无统计学意义(P>0.05)。早期AKI患者伤后首次血乳酸、血尿素氮、血肌酐和血肌酸激酶值的ROC曲线下总面积分别为0.872(95%CI 0.703~1.000,P<0.05)、0.722(95%CI 0.477~0.967,P>0.05)、0.411(95%CI 0.143~0.679,P>0.05)和0.656(95%CI 0.400~0.911,P>0.05)。伤后首次血乳酸浓度的最佳阈值为3.5 mmol/L,其对早期AKI加重预测的敏感度为100%,特异度为72.7%。加重组30 d病死率显著高于未加重组(P<0.05)。结论特重度烧伤患者伤后首次血乳酸浓度升高是AKI加重的早期预测指标,其早期预测价值优于血肌酐、血尿素氮和血肌酸激酶等常规指标。

Objective To investigate the value of early lactate levels in predicting the progressionof acute kidney injury (AKI) in patients with extremely severe burns.Methods A retrospective casecontrol study was conducted to analyze 30 severe burn patients with early AKI who met the AKIhierarchical diagnostic criteria JP3 (RIFLE) and occurred within 72 hours after injury in the aluminiumdust explosion accident in Kunshan City,Jiangsu Province on August 2,2014.There were 20 males and10 females,aged 20-50 years [(37.1 ± 7.4) years].The total area of burn was 75%-100% of total bodysurface area (TBSA) [(95.5 ± 4.3) % TBSA].Acute Physiological and Chronic Health Evaluation Ⅱ(APACHE Ⅱ) score ranged from 7 to 20 points [(13.0 ± 2.7)points].According to the progression ofrenal injury within one week after injury,the patients were divided into aggravation group and non-aggravation group,with 15 patients in each group.Laboratory examinations upon admission such as whiteblood cell (WBC),platelet,and plasma albumin,medical treatments during the first week after burninjury and 30-day mortality were compared between the two groups.The blood lactic acid,urea nitrogen,creatinine concentration and crinetime kinase in 72 hours after injury were compared between the twogroups.The receiver operative characteristic (ROC) curve of early blood lactic acid,blood urea nitrogen,creatinine concentration and crinetime kinase in patients with early AKI after injury was drawn to evaluateits predictive effect on early AKI aggravation in patients with severe burn.Results The plasma albuminconcentration of patients in the aggravation group was higher than that in the non-aggravation group onadmission to ICU (P < 0.05).There were no significant differences in concentrations of WBC andplatelet upon admission and application of nephrotoxic antibiotics during the first week after burn injurybetween the two groups (P > 0.05).In the aggravation group,the blood lactate concentration at 24 and48 hours after injury did not change significantly compared with the first detection after injury (P >0.05),but the concentration at 72 hours after injury was significantly lower than the first detection (P <0.05).In the non-aggravation group,the blood lactate concentrations at 24 hours,48 hours,72 hoursafter injury were not significantly different compared with the first detection (P > 0.05).The first bloodlactate concentration in the aggravation group was significantly higher than that in the non-aggravationgroup (P < 0.05),but there were no significant differences in the concentrations between the early AKIaggravation group and the non-aggravation group at 24 hours,48 hours and 72 hours after injury (P >0.05).The blood urea nitrogen concentration of patients in the early AKI aggravation group was higherthan that in non-aggravation group on admission (P < 0.05),and no differences were observed in serumncreatine and creatine kinase concentrations between these two groups (P > 0.05).The serumn creatineand creatine kinase concentrations of patients in the aggravation group were higher than those in non-aggravation group 24,48,and 72 hours after burn injury (P <0.05),and no difference was observed increatine kinase concentration between these two groups (P > 0.05).The total area under ROC curve offirst blood lactic acid,blood urea nitrogen,creatinine and crinetine kinase in early AKI patients were0.872 (95%CI0.703-1.000,P<0.05),0.722 (95%CI0.477-0.967,P>0.05),0.411 (95%CI0.143-0.679,P>0.05) and 0.656 (95%CI0.400-0.911,P>0.05).The optimum threshold for thefirst blood lactate concentration after injury was 3.5 mmol/L.The sensitivity and specificity for predictingearly AKI exacerbation were 100% and 72.7%,respectively.The 30-day mortality rate in the aggravationgroup was significantly higher than that in the non-aggravation group (P < 0.05).Conclusion The firstblood lactate concentration in patients with severe burn is an early predictor of AKI aggravation,and itsearly predictive value is better than that of routine indicators such as serum creatinine blood urea nitrogenand crinetine kinase.