Passive leg elevation and head-down tilt: effects and duration of changes

On the one hand, the autonomic [2] and haemodynamic effects [3–5] of postural manipulation have been shown to be both minimal and short lived. I surmise that the adverse effects observed may have been self-correcting during the course of PLE, rather than only after resumption of the supine position (i.e. before time point 4). This perhaps thereby minimises the clinical importance of these effects. On the other hand, the patterns of changes seen with HDT are very similar to those induced by PLE [2,3].