[An evaluation of stroke volume variation as a predictor of fluid responsiveness in mechanically ventilated elderly patients with severe sepsis].

OBJECTIVE: To evaluate stroke volume variation (SVV) as a predictor of fluid responsiveness in mechanically ventilated (MV) elderly patients with severe sepsis. METHODS: A prospective observation of 31 fluid challenges during fluid resuscitation for treatment of hemodynamic instability in 17 elderly MV patients with severe sepsis was conducted. SVV was measured by pulse indicator continuous cardiac output (PiCCO) system. Fluid responsiveness was defined as the changes in cardiac index (CI) increase after fluid loading (DeltaCI) > or =10%. The changes in hemodynamic parameters and lung water index were observed at the onset of and after fluid therapy. The correlation between DeltaCI and SVV or central venous pressure (CVP) were analyzed. RESULTS: SVV was decreased significantly after fluid loading [(6.6+/-2.1)% vs.(12.1+/-3.7)%, P<0.01], whereas CVP increased significantly [(12.5+/-3.6) mm Hg vs. (8.9+/-4.1) mm Hg, 1 mm Hg=0.133 kPa, P<0.01]. DeltaCI in response to fluid loading were positively correlated to initial values of SVV (r=0.447, P=0.012), but there was no relationship between CVP and DeltaCI (r=-0.082, P=0.674). The areas under the receiver operating characteristic curve (ROC curve) for SVV was 0.672 [95% confidence interval (95%CI) 0.463-0.885] and CVP was 0.336 (95%CI 0.133-0.539), respectively. A SVV value of 11.5% had the sensitivity of 71% and specificity of 67% for prediction of fluid responsiveness. CONCLUSION: Functional hemodynamic parameter SVV can predict fluid responsiveness in elderly MV patients with severe sepsis during fluid resuscitation, it may serve as a useful index for guiding fluid therapy in elderly patients with severe sepsis.