Are transient ischemic attack patients with fluctuations at highest risk for early stroke?
Patients with unstable transient ischemic attacks immediately after onset of clinical symptoms are at high risk for subsequent stroke - they may benefit from Stroke Unit management and potential early thrombolysis once they develop strokes.
First, the standard model of single-ventricle physiology can be reexpressed in a form allowing analysis by differential calculus, which allows broader conclusions to be drawn than does computer modeling alone. Second, the classic measure DO(2) fails to reflect the fact that proportional changes in saturation and flow are not clinically equivalent. Recognizing this asymmetry by using D(u)O(2) can give a target Qp:Qs balance that better represents clinical experience. Finally, to avoid an arbitrary choice of Sat(Thresh), systemic venous oxygen saturation (SsvO(2)) may be a useful parameter to maximize: this occurs at a Qp/Qs ratio of 1. Attempts to increase DO(2) by altering Qp/Qs away from this value will inevitably reduce SsvO(2) and therefore tissue oxygenation. Oxygen delivery is far from synonymous with tissue oxygen status.