Serum D-lactate levels as a predictor of intestinal ischemia-reperfusion injury

Currently, no serum marker has proved helpful in diagnosing intestinal ischemia and reperfusion (I/R) injury. An experimental study was conducted to determine the value of serum D-lactate in detecting intestinal I/R injury. Thirty New Zealand White rabbits were divided into three groups of 10 animals each: sham-operation controls (S); I/R; and I/R plus mannitol treatment (M). Serum samples were obtained before operation (T-0), at the end of the ischemic period (T-1), after the first 30 min of reperfusion (T-2), and at the end of the reperfusion period (T-3) In Group S, mean D-lactate levels for T-0, T-1, and T-2 were 0 mu g/dl, while T-3 was 5.8 +/- 4.7 mu g/dl. Before the operation (T-0), Serum mean D-lactate levels were 0 mu g/dl in all groups (S, I/R, M). Levels increased after 1 h of ischemia (T-1) in groups I/R (83.5 +/- 25.6 mu g/dl) and M (89.8 +/- 19.9 mu g/dl), but not in group S (0 mu g/dl). The mean T-2 level in group I/R (231.6 +/- 78.6 mu g/dl) was statistically higher than in group M (140.1 +/- 53.5 mu g/dl) (P = 0.007). At the end of the reperfusion period, the mean T-3 level in group I/R (698.4 +/- 360.4 mu g/dl) was significantly higher than in group M (158.7 +/- 61.4 mu g/dl)(P = 0.000). In group I/R, mean D-lactate levels changed significantly at each time point (T-1 vs T-2, P = 0.001; T-2 VS T-3, P = 0.004). However, in group M the increase from T-1 to T-2 was significant (P = 0.012), but that from T-2 to T-3 was not (P = 0.293). As a result, the mean T-3 level was significantly higher than the T-2 level in group I/R (P = 0.004), but not in group M. This study confirmed a significance rise in D-lactate levels in animals with I/R injury compared to sham-operated and I/R injury plus M treatment. We suggest that serum D-lactate levels could be a useful marker of intestinal I/R injury before laparatomy.