ITBI和GEDI评估心源性肺水肿患者心脏前负荷变化的局限性

Limitations of intrathoracic blood volume index and global end-diastolic volume index for assessment of preload changes in patients with cardiogenic pulmonary edema

目的研究胸腔内血容积指数(ITBI)和全心舒张末容积指数(GEDI)能否充分评估心源性肺水肿患者心脏前负荷状态。方法对8例心源性肺水肿患者,应用肺动脉导管(SWAN-GANZ)和脉搏指示连续心输出量(PiCCO)监测血流动力学,持续肾脏替代治疗(CRRT)减轻心脏前负荷,分别监测CRRT开始时、8h、16h和24h的中心静脉压(CVP)、肺动脉楔压(PAWP)、ITBI、GEDI等血流动力学指标,分析随着前负荷的减少,这些指标的变化。结果在超滤8h后CVP和PAWP下降即出现显著变化(17.3±2.5vs.16.1±2.2和39.6±4.2vs.36.0±4.2,P<0.01),并随着超滤时间延长,下降更明显,而ITBI和GEDI到超滤24h才出现显著下降(971±133vs.898±51和779±103vs.719±40,P<0.05);CVP、PAWP、ITBI和GEDI随着前负荷减少的变异度分别为(16.29±10.37)%、(19.35±9.86)%、(2.95±6.02)%和(3.25±6.03)%。结论 IBTI和GEDI在评估心源性肺水肿患者的前负荷状态时敏感性低于CVP和PAWP。

Objective To evaluate the limitation of intrathoracic blood volume index （ITBI） and global end-diastolic volume index （GEDI） for assessment of preload changes in critically ill patients with cardiogenic pulmonary edema. Methods Eight patients with cardiogenie pulmonary edema were enrolled. Central venous pressure （CVP）, pulmonary capillary wedge pressure（PAWP） and cardiac output index（CI） were obtained from a pulmonary artery catheter, and ITBI, GEDI, extravascular lung water index （ELWI） were recorded from a PiCCO plus monitor. Preload was reduced by continuous renal replacement therapy（CRRT）. The whole set of hemodynamic measurements was performed when CRRT began （ TO ）, 8 hours （ T1 ）, 16 hours （ T2 ） and 24 hours（T3） later. Results CVP and PAWP reduced significantly at T8 comparing with TO （16.1±2.2vs. 17.3 ±2.5and36.0±4.2 vs. 39.6±4.2, P〈0.01） and changed more with CRRT progressing, while ITBI and GEDI reduced significantly only when 24 hours later. The variability of CVP, PAWP, ITBI and GEDI was （16.29 ±10.37）%, （19.35 ±9.86） %, （2.95± 6.02 ） % and （ 3.25 ±6.03 ） %, respectively. Conclusion ITBI and GEDI are less sensitive than CVP and PAWP in assessment of preload changes in patients with eardiogenic puhnonary edema.