An observational study on the effects of nadroparin-based and citrate-based continuous venovenous hemofiltration on calcium metabolism.

BACKGROUND

To study calcium homeostasis during citrate-based compared to nadroparin-based CVVH in critically-ill patients with acute renal failure.

METHODS

11 patients were observed during citrate anticoagulation, 9 with nadroparin and 10 controls. Citrate was chosen for patients with active or at risk for bleeding.

RESULTS

The controls had, at 24 h, a median serum iCa of 1.1 mmol/l, the citrate group 0.87 mmol/l and the nadroparin group 1.1 mmol/l (citrate vs. control p = 0.001, citrate vs. nadroparin p = 0.002). At 48 h, iCa was not significantly different anymore. Ca balance was negative for the citrate group in contrast to the nadroparin group (p = 0.012). Median serum PTH was higher (30.0 pmol/l vs. 6.5 pmol/l, p = 0.003) in the citrate group.

CONCLUSION

With a relative low target-serum-iCa (0.8-0.9 mmol/l) citrate CVVH-treated patients had a negative daily calcium balance and a temporarily lower iCa level resulting in an enhanced PTH response in comparison to nadroparin.