强离子隙在急性呼吸衰竭中的应用研究

Evaluation of Strong Ion Gap in Patients with Acute Respiratory Failure

目的评估强离子隙(SIG)作为急性呼吸衰竭(ARF)患者死亡风险预测因子的临床价值。方法在测定血气、血p H值、电解质结果基础上,应用Stewart-Figge方法学的方程式计算SIG。结果 (1)ARF发生率最高的基础疾病是急性呼吸窘迫综合征(占26%)和心源性肺水肿(占26%)。(2)ARF组T1与对照组相比,除Na+和PO-4无差别外,其余各指标差异均有统计学意义(P<0.01);但恢复组T2与对照组相比,各指标差异均无统计学意义。(3)发生ARF的患者中,恢复组T1与死亡组T1检测各指标比较:两组间只有AG、SIG差异有统计学意义(P<0.01)。(4)AG和SIG相关ROC曲线参数比较:SIG曲线下面积更大达到0.904,诊断准确性高;以15.4mmol/L作为AG的cut-off值,以6.77mmol/L作为SIG的cut-off值,计算相关ROC曲线参数,SIG的敏感度、Youden指数、阴性预测值、阴性似然比等参数优于AG。结论 (1)在发生ARF之初,AG和SIG就可以较敏感地体现患者的复合酸碱紊乱状态,且AG和SIG有可能作为预测ARF患者死亡风险的预测因子,提示预后不良。(2)作为ARF患者死亡风险的预测因子,SIG优于AG。(3)当cut-off值设为6.77mmol/L时,SIG的检测结果低于cut-off值,SIG的阴性似然比为0,敏感度高达1.000,如果诊断结果为阴性,能立刻排除患者死亡风险。

Objective To evaluate the probability that strong ion gap was selected as predictive factor of mortality in patients with a -cute respiratory failure.Methods SIG was calculated with the Stewart -Figge model, after determination of blood gas ,blood pH,serum electrolytes.Results ①The incidence of acute respiratory distress syndrome and source pulmonary edema was 26% respectively in pa-tients with ARF.②There was a significant difference in the values of K ＋、Cl-、HCO3-、AG、pH、ALB、SIG、Cr,lactic acid,PaCO2 and PaO2 between group T 1 and control .However , there was no significant difference between recovery group T 2 and control .③There was a signifi-cant difference in the value of AG and SIG between the recovery group T 1 and death group T 1 from the patients with ARF .④SIG was a better predictor than AG by the evaluation of ROC curve .Conclusions AG and SIG can reflect the worse condition of acid -base disturb-ance in patients with ARF sensitively at the first beginning .Meanwhile , SIG may be served as a predictor for risk of mortality in patients with ARF better than AG .