Q: What is the formula for Lactic acid Clearance?

Answer: 

Lactic acid clearance = the initial lactate - subsequent lactate/initial lactate × 100

It is estimated that an 11% decrease in mortality for each 10% decrease in lactate clearance.

References:

1. Arnold RC, Shapiro NI, Jones AE, et al; Emergency Medicine Shock Research Network (EMShockNet) Investigators. Multicenter study of early lactate clearance as a determinant of survival in patients with presumed sepsis. Shock 2009;32(1):35–39

2. Nguyen HB, Rivers EP, Knoblich BP, et al. Early lactate clearance is associated with improved outcome in severe sepsis and septic shock. Crit Care Med 2004;32(8):1637–1642