Antithrombin III activity in Chinese women with preeclampsia

Physiological changes of pregnancy and the Swansea criteria in diagnosing acute fatty liver of pregnancy

The Swansea criteria are used to assess the likelihood of acute fatty liver of pregnancy. There are significant physiological changes in normal pregnancy in several of the pathology parameters used in the Swansea criteria. This may impact the sensitivity and specificity of the Swansea criteria. Five of the 11 case series reporting laboratory values in acute fatty liver of pregnancy used values divergent from the Swansea criteria. When using the Swansea criteria for diagnosis of acute fatty liver of pregnancy, using pregnancy-specific and/or laboratory-specific reference intervals is recommended. Simpler diagnostic criteria using parameters of hepatocellular damage and hepatic synthetic dysfunction may be an alternative to the Swansea criteria, and further studies investigating the sensitivity and specificity of these parameters would be useful.

Review article: Investigations and the pregnant woman in the emergency department - part 1: Laboratory investigations

Accurate assessment of the pregnant patient in the ED depends on knowledge of physiological changes in pregnancy, and how these changes may impact on pathology tests, appearance on point-of-care ultrasound and electrocardiography. In addition the emergency physician needs to be cognisant of disorders that are unique to or more common in pregnancy. Part 1 of this review addresses potential deviations in laboratory investigation reference intervals resulting from physiological alterations in pregnancy, and the important causes of abnormal laboratory results in pregnancy. Part 2 will address the role of point-of-care ultrasound in pregnancy, physiological changes that may affect interpretation of point-of-care ultrasound, physiological changes in electrocardiography, and the safety of radiological procedures in the pregnant patient.

Elimination of antithrombin III concentrate in healthy pregnant and preeclamptic women with an acquired antithrombin III deficiency

The activity elimination half-life of heat-treated antithrombin III (AT III) concentrate was studied in 5 healthy pregnant and 5 preeclamptic women with a documented AT III deficiency. Healthy pregnant women received 1500 units over 20 minutes. Serial blood specimens were obtained over the next 12 hours. The mean (+/- SEM) activity elimination half-life of AT III was 29.4h +/- 3.4h. Preeclamptic subjects had a mean baseline AT III activity of 70.5 +/- 2% (range 61 to 75%). Their activity eliminator half-life after 3000 units of AT III concentrate was 8.5 +/- 1.2h. There was a direct relationship between the pre-concentrate AT III activity level and the AT III activity elimination half-life (r = 0.79, p = 0.01) for all subjects. Based upon parameters calculated from the first infusion, the AT III activity of preeclamptic subjects was maintained by a constant infusion at approximately 100% for 96h. At the conclusion of the infusion, the activity elimination half-life was again measured. A dramatic increase in the activity elimination half-life was demonstrated (433.6h). We conclude that the activity elimination half-life of AT III concentrate is increased during normal pregnancy and further increased in preeclamptic women with an acquired deficiency.