Peri-operative hemodynamic therapy: only large clinical trials can resolve our uncertainty.

MacDonald, Neil; Pearse, Rupert M

In this issue of Critical Care, Cecconi and colleagues report the findings of a small trial of goal-directed hemodynamic therapy (GDT) in patients undergoing major orthopedic surgery under regional anesthesia. This is an interesting trial and the first of which we are aware to test the efficacy of GDT in this patient group. The findings suggest that this intervention is associated with improved adverse event rates after surgery. However, in this trial, as in all small trials of GDT, the potential for bias leaves some uncertainty regarding how widely the findings should be implemented. Such limitations may be impossible to completely eliminate from trials of complex interventions, but large multicenter trials may allow us to substantially decrease bias and improve the generalizability of the findings.