Abstract: Objective To assess fluid responsiveness in mechanically ventilated patients with septic shock by central venous pressure(CVP)and global end diastolic volume index(GEDVI). Methods Fifty-five mechanically ventilated patients with septic shock underwent 55 liquid load tests(LLT),within 30 minutes,the subjects received an intravenous infusion of 6 ml/kg of 6%hydroxyethyl starch(200/0.5).The CVP was monitored through a catheter introduced via the right internal jugular vein and the subclavian vein.The cardiac index(CI)and GEDVI before and after fluid loading were monitored by pulse-induced contour cardiac output(PiCCO).Positive fluid responsiveness was defined as an increase in CI(△CI)by 15% or more.Hemodynamic changes before and after LLT were observed and the correlations between CVP,GEDVI and △CI were assessed.Results The change rate of CVP after volume treatment of responders was higher than that of non-responders,but there was no significant difference (P > 0.05 ).The change rate of GEDVI after volume treatment of responders was higher than that of non-responders,there was significant difference(P <0.01).CVP and GEDVI before the resuscitation showed increase after the resuscitation.There was no significant correlation between △CVP and △CI,while there was positive correlation between △GEDVI and △CI(r =0.816,P <0.01).Conclusion Compared with CVP,GEDVI can better reflect cardiac preload in septic shock patients,and predict fluid responsiveness.

Key words: shock, respiration, artificial, central venous pressure, cardiac output