Table 1.

The dynamic markers^a

Dynamic Marker	Definition
SPV	The difference between the maximum systolic pressure and minimal systolic pressure after a breath
ΔDown	The decrease in arterial pressure during expiration
PPV	The maximum minus the minimum of the pulse pressure divided by the average of the two over a mechanical breath
SVV	The percentage change between the maximum stroke volume and minimum stroke volume over a designated interval

^aPPV, pulse pressure variation.