脓毒性休克早期液体复苏对血管外肺水的影响及相关因素研究

目的探讨脓毒性休克早期液体复苏对血管外肺水（EVLW）的影响及相关因素研究。方法选择20例脓毒性休克早期存在血容量不足即胸内血容量指数（ITBVI）〈750ml／m^2]的患者，给予血定安快速液体复苏至ITBVI〉850ml／m^2为复苏终点，采用单指示剂热稀释法测定的血管外肺水指数（EVLWI），根据入选时EVLWI监测值将患者分为EVLWI≤7ml／kg（n=8）及EVLWI〉7ml／kg（n=12）两组，监测液体复苏前（Tb）及复苏结束后即刻（T0）、1h（T1）、2h（T2）、4h（T4）血流动力学、EVLWI、氧合指数（PaO2／FiO2）等指标的变化。结果①两组患者在达到液体复苏终点后T0、T1、T2时ITBVI、全心舒张末期容积指数（GEDVI）、心排血指数（CI）、每搏指数（SI）、中心静脉压（CVP）均明显增高（P〈0.05或P〈0.01），但T4与Tb相比差异均无显著性（P均〉0．05）；两组同时间点ITBVI、GEDVI、CI、SI、CVP比较差异均无显著性（P均〉0．05）。②与Tb相比，两组在T0、T1、T2、T4时EVLWI、PaO2／FiO2均无明显改变（P均〉0．05），但EVLWI〉7ml／kg组在各相同时间点PaO2／FiO2均显著低于EVLWI≤7ml／kg组（P均〈0．05）；③在早期复苏过程中EVLWI与ITBVI、GEDVI、CI、SI、CVP均无明显相关性（P均〉0．05），与PaO2／FiO2具有负相关性（r=-0．765，P〈0．01），与肺毛细血管渗透性指数（PVPI）呈正相关（r=0．678，P〈0．01）；④20例患者中28d内死亡6例（占30％），死亡患者复苏前后EVLWI均显著高于存活患者（P均〈0．05），但复苏前后EVLWI变化值（△EVLWI）比较差异无显著性（P〉0．05）。结论脓毒性休克早期进行液体复苏可使ITBVI、GEDVI、CI、SI、CVP增加，但不影响EVLW及氧合。EVLWI的升高可能与PVPI增加有关，与PaO2／FiO2呈负相关，并与患者预后密切相关。

Effect of fluid resuscitation on extravascular lung water in early stage of septic shock

OBJECTIVE: To determine the effect of fluid resuscitation on extravascular lung water (EVLW) in early stage of septic shock. METHODS: Twenty septic shock patients with hypovolemia intrathoracic blood volume index (ITBVI)<750 ml/m(2)] were randomly divided into two groups: EVLW index (EVLWI)< or =7 ml/kg group (n=8) and EVLWI >7 ml/kg group (n=12) according to the EVLWI value determined on admission day. Fluid resuscitation was given at 250 ml in bolus every 15 minutes until the end point of ITBVI>850 ml/m(2) was reached. Repeated haemodynamic measurements were done at baseline (Tb), at the end point (T0) then at 1 hour (T1), 2 hours (T2) and 4 hours (T4) after the end point of resuscitation was reached. EVLWI, pulmonary vascular permeability index (PVPI), ITBVI, global end-diastolic volume index (GEDVI), cardiac index (CI), stroke index (SI), central venous pressure (CVP) and oxygenation index (PaO(2)/FiO(2)) were determined at each time point, and the outcomes of these patients after 28 days were recorded. RESULTS: (1)ITBVI, GEDVI, CI, SI, CVP were increased significantly at T0 and remained elevated at T1 and T2 in two groups (P<0.05 or P<0.01), but declined at T4 with no significant difference compared with those at Tb (all P>0.05). There were also no significant differences at the same period of time between the two groups (all P>0.05). (2)No changes in PaO(2)/FiO(2) and EVLWI were found over time in two groups compared with those at Tb (all P>0.05), but the PaO(2)/FiO(2) in EVLWI>7 ml/kg group were all lower than that of EVLWI< or =7 ml/kg group at any time point (all P<0.05). (3)EVLWI was not significantly correlated with ITBVI, GEDVI, CI, SI, CVP but negatively correlated with PaO2/FiO2 (r=-0.765, P<0.01), and positively correlated with PVPI (r=0.678, P<0.01). (4)Six patients died within 28 days. EVLWI of the dead patients were prominently higher at Tb and T4 than those of survived patients (both P<0.01), but the EVLWI gap (DeltaEVLWI) had no difference before and after resuscitation (P>0.05). CONCLUSION: Fluid resuscitation in early stage of septic shock can improve ITBVI, GEDVI, CI, SI, CVP, with neither increased EVLWI nor worsened oxygenation. EVLWI has significantly negative correlation with PaO(2)/FiO(2) but not with haemodynamics. The increase in PVPI is responsible for the elevation of EVLWI. The patient's outcome is significantly correlated with the value of EVLWI.