血乳酸和乳酸清除率评估脓毒性休克患儿预后的临床分析

目的 评价血乳酸及乳酸清除率与脓毒性休克患儿预后的关系.方法 2009年10月至2011年6月我院PICU收治的脓毒性休克患儿42例,所有患儿均按照脓毒性休克诊疗方案进行早期目标指导治疗,测定每例患儿复苏前及复苏后1h、2h、6h血乳酸值,计算复苏后1h、2h、6h的乳酸清除率.按照预后将患儿分为存活组(n=20)和死亡组(n=22),评价早期乳酸值和乳酸清除率与预后的关系.结果 (1)存活组复苏前及复苏后1h、2h、6h的乳酸值明显低于死亡组[(3.92±2.58) mmol/Lvs (6.91 ±4.16) mmol/L,(2.79±1.89) mmol/L vs (7.93±4.39) mmol/L,(2.20±1.83) mmol/L vs(9.20±4.97) mmol/L,(1.32±0.51) mmol/L vs (9.94±5.02) mmol/L],差异具有统计学意义(P＜0.05).(2)存活组复苏后1h、2h、6h的乳酸清除率明显高于死亡组[(26.31 ±20.82)％ vs(-24.28±53.39)％,(43.46±17.85)％ vs(-34.31±58.98)％,(61.04±16.71)％ vs(-45.33±83.51)％],差异具有统计学意义(P＜0.05).(3)通过受试者工作特征曲线分析,复苏后6h血乳酸值和乳酸清除率的曲线下面积分别为99.4％、96.7％;复苏后6h血乳酸＞2.20 mmol/L及复苏后6h乳酸清除率＜18.65％,患儿病死率高.结论 脓毒性休克患儿动态监测血乳酸具有重要意义,复苏后6h的血乳酸值及乳酸清除率可作为预后判断的指标.     

婴儿复杂先天性心脏病术后乳酸及乳酸清除率的监测

目的探讨动态血乳酸水平、乳酸清除率在婴儿复杂先天性心脏病心内直视手术后疗效及预后评估中的意义。方法将118例婴儿复杂先天性心脏病患儿分为生存组和死亡组,测定两组体外循环心内直视手术后即刻、术后12 h、24 h、36 h、48 h血乳酸水平及乳酸清除率的动态变化,评估其与预后的关系。结果体外循环心内直视手术后12 h两组血乳酸水平均较术后即刻略有上升(3.54±1.62 mmol/L vs 4.33±0.71 mmol/L,P>0.05),随后生存组血乳酸水平逐步下降(P<0.05),而死亡组血乳酸水平呈持续升高趋势(P<0.05)。生存组血乳酸水平较死亡组明显下降(1.57±0.54 mmol/L vs 7.56±1.72 mmol/L,P<0.05)。生存组乳酸清除率明显高于死亡组(5.85%±29.75%vs -32.33%±25.04%,P<0.001)。结论婴儿复杂先天性心脏病术后血乳酸水平和乳酸清除率的动态变化与预后有密切关系,术后血乳酸水平持续增高,乳酸清除率低,提示预后差。     

Agreement between capillary and arterial lactate in the newborn

Arterial blood lactate is a reliable indicator of tissue oxygen debt and is of value in expressing the degree and prognosis of circulatory failure as a result of various diseases. Therefore, the practical issue of whether capillary lactate measurements might be of equal value was investigated in newborns. In total, 193 simultaneous measurements of capillary and arterial blood lactate concentrations were performed in 25 newborn babies with an indwelling umbilical arterial catheter. A strong linear correlation was found between capillary and arterial lactate concentration (Lcap = 1.02 Lart + 0.04; r = 0.98; p < 0.001). The mean difference was -0.08 mmol/l and the limits of agreement (+/- 2 SD) were +/- 0.69 mmol/l (-0.77 to 0.61 mmol/l). Conclusion: Our data show that capillary blood lactate measurements in newborn babies yield lactate concentrations equivalent to arterial measurements over a large concentration range.     

The significance of elevated CSF lactate

The final diagnosis of 158 patients who had a cerebrospinal fluid (CSF) lactate concentration greater than 2 mmol/l was ascertained. The conditions included seizures, inflammatory changes, and proven metabolic disorders. For the diagnosis of congenital lactic acidoses, CSF lactate should ideally be measured in a seizure free patient after any acute illness.     

Brain lactate in preterm and growth–retarded neonates

Glucose is the predominant cerebral energy source under physiological conditions, although other substrates may support cerebral metabolism. The present study was undertaken to determine if lactate is present in the immature human brain, and if so, whether or not concentrations of lactate differ between small–for–gestational–age and appropriate–for–gestational–age infants. Thirty stable, healthy infants with normal brains were investigated. As the only nutrient, all received milk enterally prior to the investigation, which was carried out without sedation. Mean gestational age was 35 completed weeks (range 28–41 weeks) and mean birth weight was 2170g (range 855–4100 g). Proton nuclear magnetic resonance spectra from the striatal region were obtained while the infants were sleeping quietly. Lactate was present in all 10 preterm small–for–gestational–age and 10 of 13 preterm appropriate–for–gestational–age infants, and the concentration was inversely related to postmenstrual age ( p < 0.002). In addition, lactate increased with the degree of growth retardation ( p < 0.01). At present the significance of lactate is unclear. Lactate may be produced locally or in peripheral tissues, and may support brain metabolism.     

The significance of elevated CSF lactate.

The final diagnosis of 158 patients who had a cerebrospinal fluid (CSF) lactate concentration greater than 2 mmol/l was ascertained. The conditions included seizures, inflammatory changes, and proven metabolic disorders. For the diagnosis of congenital lactic acidoses, CSF lactate should ideally be measured in a seizure free patient after any acute illness.     

Serum lactate dehydrogenase isoenzyme pattern in neuroblastoma

Total serum LDH activity and isoenzyme distribution were studied in children with neuroblastoma at the time of hospital admission. The total LDH was determined in 26 cases, and 20 (77%) of them showed elevation of its activity. On the other hand, in 9 of these 26 cases, the isoenzyme distribution was determined along with the total LDH. All 9 cases, 4 of them with normal total LDH activity, showed an abnormal isoenzyme pattern with a percentage increase in the intermediate fractions (malignant pattern). The results suggest the usefulness of the determination of serum LDH isoenzymes as a screening procedure in children with malignant tumors including neuroblastoma.