F2 and acute kidney injury: This finding is similar to that in patients with liver failure and AKI who received CVVHD, in which serum lactate levels greater than or equal to 3.4 mmol/L and prothrombin time activity less than or equal to 26% predict an increase in citrate accumulation with high sensitivity (86% for both lactate and prothrombin time activity) and specificity (86% for lactate; 92% for prothrombin time) [9].