Table 1.

Measures of fluid responsiveness. IVC, inferior vena cava; LVOT, left-ventricular outflow tract; SVC, superior vena cava; VTI, velocity-time interval. *The SVC can be difficult to visualise with transthoracic echocardiography but can be seen on transoesophageal echocardiography

	Clinical assessment	Echocardiography assessment
Static pressure and volume measures	Blood pressure Heart rate Urine output Lactate Mean arterial pressure Central venous pressure Mixed venous oxygen saturation Pulmonary capillary wedge pressure/pulmonary artery occlusion pressure Flow time corrected	End-diastolic ventricular volumes, area and diameters Size of the IVC Left ventricular end-diastolic pressure
Dynamic measures based on heart–lung interactions	Passive leg raise Pulse pressure variation End-expiratory occlusion Pleth variability index Rapid fluid challenge Mini fluid challenge	LVOT maximum velocity LVOT VTI Stroke volume variation Distensibility index of IVC Collapsibility index of SVC*