Early visual signs of ischemia are unreliable. Noninvasive measures such as Doppler flow, pulsatility, and capillary refill are imperfect predictors of outcome, while invasive tests (such as lactate) respond slowly and cannot be used for real-time management.

T-Stat® has been proven in multiple trials to be sensitive to ischemia, and is the first device allowed to be labeled "sensitive to ischemia". T-Stat® is correlated to measures of venous saturation (r²=0.94), the same value Intensivists already demand in their sickest patients. Why? Because venous saturation is well correlated with clinical outcome… yet until now, Svo2 could not be locally measured, and thus was not available for routine use.