血乳酸水平及清除率和升高时间与重症监护病房危重患者预后的关系

目的 探讨乳酸动态监测指标与重症监护病房(ICU)危重患者预后的相关关系,并对这种关系进行量化评价.方法 收集101例乳酸升高的危重患者,分为死亡组(50例)和存活组(51例),比较两组的乳酸监测指标(乳酸水平、乳酸升高时间、乳酸清除率)、急性生理学与慢性健康状况评分系统Ⅰ(APACHE Ⅰ)评分及其他反映器官功能的指标,使用logistic回归分析找出与预后显著相关的指标.以相应的乳酸指标进行量化分组,分别比较各组休克和多器官功能障碍综合征(MODS)发生率、APACHE Ⅰ评分和病死率.结果 死亡组入ICU乳酸值、乳酸峰值、APACHE Ⅰ评分高于存活组,12 h和24 h乳酸清除率、pH值低于存活组(P<0.05或P<0.01).乳酸峰值、12 h乳酸清除率、APACHE Ⅰ评分和pH值与患者的预后明显相关,相对比值比(OR)分别为1.466、0.922、1.208、0.032.乳酸峰值≥10 mmol/L、12 h乳酸清除率≤10%的患者病死率明显升高,分别为77.8%和70.6%(P<0.05和P<0.01),乳酸升高时间>24 h时病死率虽升高,但无统计学意义.结论 乳酸峰值、12 h乳酸清除率、APACHE Ⅰ评分和pH值是评价患者预后的良好指标.乳酸峰值≥10 mmol/L、12 h乳酸清除率≤10%时应警惕患者较差的预后,而乳酸升高时间评价预后的价值有限.

Relationship between blood lactic level, lactic clearance, duration of lacticemia and prognosis of critically ill patients in intensive care unit

Objective To study and quantify the relationship between dynamic lactic acid monitoring indexes and prognosis of critically ill patients in intensive care unit (ICU). Methods One hundred and one critically ill patients with elavated blood lactic acid level were included in this study and divided into death group (n= 50) and survival group (n = 51). Differences in their lactic acid indexes (including: lactic acid level, duration of lacticemia, lactic clearance), acute physiology and chronic health evaluation Ⅰ (APACHE Ⅰ ) score, and other clinical indicators which reflected organ/system status were compared, and prognostic significant lacticemia indexes were formulated by multi-variable logistic analysis. Subsequently, patients were grouped by significant lactic indexes separately and compared with incidence of shock/multiple organ dysfunction syndrome (MODS), APACHE Ⅰ score and mortality. Results Differences in lactic acid level, peak lactic acid level, 12-hour and 24-hour lactic acid clearance between death group and survival group showed statistically significant difference (P<0. 05 or P<0. 01). Peak lactic acid level, 12-hour lactic clearance, APACHE Ⅰ score and blood pH had significant correlation with prognosis, odds ratios (OR) were 1. 466, 0. 922, 1. 208, 0. 032, respectively. Patients with peak lactic acid value≥10 mmol/L or 12-hour lactic clearance≤10% had significantly higher mortality: 77. 8% and 70. 6%, respectively (P<0. 05 and P< 0.01). Although patients with lacticemia > 24 hours had higher mortality, there was no statistically significant difference. Conclusion Peak lactic acid level, 12-hour lactic clearance, APACHE Ⅰ score and blood pH are good indicators to evaluate patients' prognosis. Peak lactic acid value≥10 mmol/L or 12-hour lactic clearance≤10% is an alert of extremely bad prognosis. Prognosis value of duration of lacticemia is limited.