The elusive relationship between cardiac filling and fluid responsiveness

Additionally, FR was measured pragmatically based on either pulse pressure variation, stroke volume variation, passive leg raising, or end expiratory occlusion test (considering the presence of arrhythmias, spontaneous ventilation, and the availability of monitoring devices). In a pilot study using simultaneous common carotid artery and internal jugular Doppler ultrasonography in emergency department (ED) patients deemed to require intravenous fluid expansion we, like Munoz and colleagues, observed a high proportion (i.e., 67%) of FUR assessments with jugular venous Doppler morphologies consistent with low preload (i.e., normal venous measures) [4]. Within the Doppler Starling curve framework, this constellation is seen in Q2 and Q4 with the proportion determined by the severity of cardiac dysfunction in the population studied (see Fig. 1).