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Pulse pressure variation and stroke volume variation predict fluid responsiveness in mechanically ventilated patients
Xiaomei Liu1, Qiang Fu, Weidong Mi
1Department of Anesthesiology, General Hospital of People's Liberation Army, Beijing 100853, China.
Abstract:
The purpose of the present study was to evaluate whether pulse pressure variation (PPV) and stroke volume variation (SVV) can predict fluid responsiveness in patients with intra-abdominal hypertension (IAH) in either a supine or Trendelenburg position. Forty mechanically ventilated patients that exhibited IAH resulting from carbon dioxide insufflation (up to 12 mmHg) underwent fluid therapy in either a supine or Trendelenburg position. Hemodynamic measurements, including PPV and SVV, were obtained before and after fluid therapy. Prediction of fluid responsiveness (> 10% increase in stroke volume) was performed by linear regression analyses. Baseline PPV and SVV values correlated closely with changes in stroke volume induced by fluid therapy, and were significantly higher in patients that subsequently responded to fluid therapy. Fluid responsiveness in patients in a supine position was predicted by a PPV threshold of > 10.5% and an SVV threshold of > 10.5%. Fluid responsiveness in patients in a Trendelenburg position was predicted by a PPV threshold of > 7.5% and an SVV threshold of > 7.0%. PPV and SVV were demonstrated to be sensitive and specific predictors of fluid responsiveness in patients with IAH in both the supine and Trendelenburg positions.
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