Presentation of laboratory and sonoclot variables using principal component analysis: identification of hypo- and...

The HELLP (Hemolysis, Elevated Liver enzyme, and Low Platelet) syndrome requires close monitoring of rapid changes in hemostasis. A bedside viscoelastic test--Sonoclot--was used together with coagulation, liver and hemolysis laboratory analyses in three parturients with the HELLP syndrome up to 10 days postpartum. Principal component analysis (PCA) was used to reduce the dimensionality of this multivariate problem and to visualize this process in a two-dimensional plot. It was possible to follow changes in these variables over time and to show how they changed in relation to 10 typical healthy parturients with normal laboratory and Sonoclot values as well as 20 simulated patients with hypo- or hypercoagubility. The effects of emergency delivery, correction of low plasma-antithrombin with plasma and antithrombin factor concentrate, plasma exchange and individualized dosages of low molecular weight heparin to counteract postpartum Sonoclot detected hypercoagulation were evaluated. The efficiency of each treatment strategy was visualized in the PCA plot by movement towards an area with normocoagulation. In conclusion, PCA of viscoelastic and laboratory coagulation analysis data facilitated the detection of both hypo- and hypercoagulative events and represents an alternative way to evaluate treatment strategies in patients with complex coagulative disorders, like the HELLP syndrome.