Payne S, MacKinnon K, Keeney M, Morrow B, Kovacs M J
Unversity of Western Ontario, Ontario, Canada.
Clin Lab Haematol. 2003 Oct;25(5):317-9. doi: 10.1046/j.1365-2257.2003.00542.x.
In this study, we compared the effect of sodium citrate, a sample collection variable, on the anti-Xa levels of patients (n = 28) on dalteparin, a low molecular weight heparin. The median anti-Xa level for 3.2% sodium citrate was 0.235 U/ml while the median level for 3.8% sodium citrate was 0.230 U/ml. We conclude that different sodium citrate concentrations give statistically equivalent anti-Xa levels for the same samples. This conclusion is in contrast to the findings of the effect of sodium citrate concentration on International Normalized Ratio (INR) and activated partial-thromboplastin time (aPTT). In accordance with previous recommendations, we advocate the exclusive use of 3.2% sodium citrate in an effort to standardize coagulation testing.
