Value of early lactate level in predicting progression of acute kidney injury in patients with extremely severe burns / 中华创伤杂志

ABSTRACT

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.