Traditionally, fluid responsiveness has been assessed by graded volume loading, but this may easily lead to fluid overload. Whether to provide a fluid bolus is a critical decision of the utmost importance in the emergency and ICU setting. Cardiac filling pressures are poor predictors of preload, and neither central venous pressure nor pulmonary artery occlusion pressure can be used to predict fluid responsiveness in patients who breathe spontaneously or in patients on positive pressure ventilation. The echocardiographic appearance of a full-blown picture of hypovolemia is consistent with a small hyperkinetic fast-beating heart. Passive leg raising has been proposed as a preload-modifying maneuver without any potentially harmful fluid infusion. This maneuver is the only reliable, easy way to predict fluid responsiveness for the patient who breathes spontaneously. The only way to avoid useless or even harmful fluid load is simply to challenge the Frank–Starling relationship. The echocardiographic methods used to predict fluid responsiveness in mechanically ventilated patients are described. Aortic flow changes during stable mechanical ventilation are the most used parameter to assess fluid responsiveness. Echocardiography, with all the vital information on cardiovascular functional anatomy it provides, has become the best tool to assess volume status, predict fluid responsiveness, and guide fluid therapy in the emergency and ICU setting.
Hypovolemia Heart–lung interaction in mechanical ventilation Fluid responsiveness Passive leg raising Echocardiographic criteria of fluid responsiveness
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Carsetti A, Cecconi M, Rhodes A. Fluid bolus therapy: monitoring and predicting fluid responsiveness. Curr Opin Crit Care. 2015;21:388–94.CrossRefGoogle Scholar
Cecconi M, De Backer D, Antonelli M, et al. Consensus on circulatory shock and hemodynamic monitoring. Task Force of the European Society of Intensive Care Medicine. Intensive Care Med. 2014;40:1795–815.CrossRefGoogle Scholar
Charron C, Caille V, Jardin F, et al. Echocardiographic measurement of fluid responsiveness. Curr Opin Crit Care. 2006;12:249–54.CrossRefGoogle Scholar
De Backer D, Taccone FS, Holsten R, et al. Influence of respiratory rate on stroke volume variation in mechanically ventilated patients. Anesthesiology. 2009;110:1092–7.CrossRefGoogle Scholar
Fehil F, Broccard AF. Interactions between respiration and systemic hemodynamics. Part I: basic concepts. Intensive Care Med. 2009;35:45–54.CrossRefGoogle Scholar
Feihl F, Broccard AF. Interactions between respiration and systemic hemodynamics. Part II: practical implications in critical care. Intensive Care Med. 2009;35:198–205.CrossRefGoogle Scholar
Gerstle J, Shahul S, Mahmood F. Echocardiographically derived parameters of fluid responsiveness. Int Anesthesiol Clin. 2010;48(1):37–44.CrossRefGoogle Scholar