Coagulation in pregnancy

Within-subject biological variation of activated partial thromboplastin time, prothrombin time, fibrinogen, factor VIII and von Willebrand factor in pregnant women

Background:

During pregnancy, interpretation of results from coagulation parameters can be difficult as the physiological changes that occur may affect the biochemical parameters. The aim of this study was to describe the normal course of five coagulation parameters in healthy pregnancies, and to estimate the within-subject biological variation (CVI).

Methods:

Blood samples were obtained every 4th week during pregnancy and three samples after delivery in 20 healthy women and every 4th week during a 40-week period in 19 healthy non-pregnant women. Activated partial thromboplastin time (APTT), prothrombin time (PT), PT International Normalized Ratio (INR), fibrinogen, factor VIII clot (FVIII:C) and von Willebrand factor antigen (vWF:Ag) were analyzed. The physiological changes during pregnancy were compensated by transformation into multiples of the median (MoM) and it is natural logarithm (lnMoM) in order to establish a kind of steady state, and CVIwas calculated from the standard deviation.

Results:

During pregnancy, APTT, PT and INR remained unchanged or decreased, depending upon the reagent used, while fibrinogen, FVIII:C and vWF:Ag increased gradually until delivery. The CVIin pregnancy were 2.2 and 3.0% for APTT, 2.3 and 2.6% for PT, 2.2 and 2.3% for INR, 7.2% for fibrinogen, 12.2% for FVIII:C and 11.3% for vWF:Ag, and corresponded with the CVIin non-pregnant women.

Conclusions:

Transformation of coagulation parameters in healthy pregnancies to MoM is a tool to establish a kind of steady state. Although there is a physiological change in these coagulation parameters during pregnancy, the CVIafter lnMoM transformation was comparable with the CVIof non-pregnant women.

Delivery-associated presence of supramolecular fibronectin-fibrin complexes in puerperal and cord plasma

Objective: The variable fibronectin (FN) molecular forms are known to be engaged in coagulation and fibrinolysis pathways as well as tissue remodeling and repair processes. Some of them seem to be indispensable molecules within intensive biological processes associated with delivery. The aim of the study was to evaluate the FN molecular status in maternal and cord plasma after vaginal birth and cesarean section (C-section). Materials and methods: The study included nonpregnant women's plasma samples (n = 31) and puerperal and cord plasma samples collected from 49 mothers who delivered healthy newborns at term by vaginal birth (n = 25) and C-section (n = 24). The maternal and cord plasma FN concentrations and presence and relative ratios of different FN-fibrin complexes were determined by ELISA and sodium dodecyl sulfate (SDS) -agarose immunoblotting, respectively. Results: FN concentration in puerperal plasma after vaginal birth (232.08 ± 71.8 mg/L) and C-section (228.17 ± 71.2 mg/L) was significantly higher than in the plasma of nonpregnant women (190.00 ± 48.75 mg/L). In contrast, FN concentration in cord plasma of the C-section group (101.95 ± 30.3 mg/L) was significantly lower than that of the vaginal birth group (121.80 ± 22.2 mg/L). Immunoblotting of puerperal and cord plasma distinguished the most abundant dimeric plasma FN form, the 220-280-kDa FN degradation products and 750-1900-kDa FN-fibrin complexes, which occurred more frequently and in higher amounts in puerperal and cord plasma groups than the nonpregnant women group, although independently of the mode of delivery. Conclusions: Occurrence and relative amount of delivery-associated FN-fibrin complexes in both puerperal and cord plasmas might be bound with the physiological adaptive mechanisms reducing the risk of hemorrhage and intensive remodeling and repair processes after delivery.

Increased circulating microparticles in women with preeclampsia

INTRODUCTION

Preeclampsia (PE) is associated with hypercoagulability, endothelial dysfunction and inflammation, which generate microparticles (MPs). Therefore, MPs may be important for PE.

METHODS

We established a verified MP measurement procedure to detect MPs in nonpregnant women (n = 25), healthy pregnant women (n = 29) and PE women (n = 73) and compared their MP levels.

RESULTS

Microparticles prepared from platelets (PMPs), endothelial cells (EMPs) and leucocytes (LMPs) were confirmed by transmission electron microscopy and were analysed by our established flow cytofluorimetric approach, which showed good specificity for determining the cell origin and level of MPs. The levels of total MPs (tMPs) and PMPs in the healthy pregnant group were significantly higher than those in the nonpregnant group (158.78 vs 93.00 and 45.04 vs 17.41, P = .004 and P = .007, respectively) but were not significantly different from those of the PE group. However, EMPs and LMPs were significantly higher in the PE group than in the healthy pregnant group (14.62 vs 11.48 and 8.94 vs 5.03, P = .015 and P < .001, respectively). Furthermore, the area under the receiver operating characteristic curves (AUC) for EMPs, LMPs and the combined sum of EMPs and LMPs were 0.661, 0.746 and 0.718, respectively (P < . 05); at their optimal cut-off values, the sensitivities were 50.68%, 87.67% and 46.58%, respectively, and the specificities were 80.77%, 58.33% and 95.65%, respectively.

CONCLUSION

Determining the MP level, especially that of EMPs and LMPs, by a specificity-verified method may reflect the endothelial dysfunction and inflammation involved in PE pathogenesis.

Risk of Epidural Hematoma after Neuraxial Techniques in Thrombocytopenic Parturients: A Report from the Multicenter Perioperative Outcomes Group

BACKGROUND

Thrombocytopenia has been considered a relative or even absolute contraindication to neuraxial techniques due to the risk of epidural hematoma. There is limited literature to estimate the risk of epidural hematoma in thrombocytopenic parturients. The authors reviewed a large perioperative database and performed a systematic review to further define the risk of epidural hematoma requiring surgical decompression in this population.

METHODS

The authors performed a retrospective cohort study using the Multicenter Perioperative Outcomes Group database to identify thrombocytopenic parturients who received a neuraxial technique and to estimate the risk of epidural hematoma. Patients were stratified by platelet count, and those requiring surgical decompression were identified. A systematic review was performed, and risk estimates were combined with those from the existing literature.

RESULTS

A total of 573 parturients with a platelet count less than 100,000 mm who received a neuraxial technique across 14 institutions were identified in the Multicenter Perioperative Outcomes Group database, and a total of 1,524 parturients were identified after combining the data from the systematic review. No cases of epidural hematoma requiring surgical decompression were observed. The upper bound of the 95% CI for the risk of epidural hematoma for a platelet count of 0 to 49,000 mm is 11%, for 50,000 to 69,000 mm is 3%, and for 70,000 to 100,000 mm is 0.2%.

CONCLUSIONS

The number of thrombocytopenic parturients in the literature who received neuraxial techniques without complication has been significantly increased. The risk of epidural hematoma associated with neuraxial techniques in parturients at a platelet count less than 70,000 mm remains poorly defined due to limited observations.

Hormonal regulation of NK cell cytotoxic activity

The effects of chorionic gonadotropin, estriol (E₃), leptin, ghrelin, and kisspeptin on the intracellular expression of perforin, granzyme A, and granzyme B was studied in separated NK cells. All studied hormones except E₃ are could modulate the expression of cytotoxic enzymes in NK cells by suppression of the expression of the most active proapoptotic agents, resulting in increased expression of granzyme A, which is typical of the decidual subpopulation of these lymphocytes.

Global hemostasis in healthy bitches during pregnancy and at different estrous cycle stages: Evaluation of routine hemostatic tests and thromboelastometry

This study assessed the global hemostasis (including prothrombin time [PT], activated partial thromboplastin time [aPTT], antithrombin activity [ATA], fibrinogen and d-Dimer concentrations, platelet count, plateletcrit and thromboelastometry) in healthy pregnant bitches, comparing the results with those of healthy bitches at different estrous cycle stages, and assessed whether hemostatic changes during pregnancy are associated with serum progesterone concentration or the presence of fetuses in utero. The results show that pregnant bitches have higher fibrinogen concentration, platelet count and platelatecrit, and that fibrin and global clot formations occur faster than in non-pregnant bitches at different estrous cycle stages. Additionally, clot strength was higher in pregnant bitches than in non-pregnant ones. There were no differences in PT, ATA, and D-dimer concentration between all study groups. The aPTT was significantly shorter in bitches at the fourth and last pregnancy weeks, compared to the anestrus group, and shorter in both the fourth and last pregnancy weeks groups, compared to diestrus group. These results all support a hypercoagulable state in healthy pregnant bitches, unassociated with progesterone concentration.

Identification and Management of Obstetric Hemorrhage

Obstetric hemorrhage remains the leading cause of maternal death and severe morbidity worldwide. Although uterine atony is the most common cause of peripartum bleeding, abnormal placentation, coagulation disorders, and genital tract trauma contribute to adverse maternal outcomes. Given the inability to reliably predict patients at high risk for obstetric hemorrhage, all parturients should be considered susceptible, and extreme vigilance must be exercised in the assessment of blood loss and hemodynamic stability during the peripartum period. Obstetric-specific hemorrhage protocols, facilitating the integration and timely escalation of pharmacologic, radiological, surgical, and transfusion interventions, are critical to the successful management of peripartum bleeding.

Associations between phenotypes of preeclampsia and thrombophilia

OBJECTIVES

Preeclampsia complicates 2-8% of all pregnancies. Studies on the association of preeclampsia with thrombophilia are conflicting. Clinical heterogeneity of the disease may be one of the explanations. The present study addresses the question whether different phenotypes of preeclampsia are associated with thrombophilia factors. Study design We planned a retrospective cohort study. From 1985 until 2010 women with preeclampsia were offered postpartum screening for the following thrombophilia factors: anti-phospholipid antibodies, APC-resistance, protein C deficiency and protein S deficiency, hyperhomocysteineamia, factor V Leiden and Prothrombin gene mutation. Hospital records were used to obtain information on phenotypes of the preeclampsia and placental histology.

RESULTS

We identified 844 women with singleton pregnancies who were screened for thrombophilia factors. HELLP complicated 49% of pregnancies; Fetal growth restriction complicated 61% of pregnancies. Early delivery (<34th week) occurred in 71% of pregnancies. Any thrombophilia factor was present in 29% of the women. Severe preeclampsia was associated with protein S deficiency (p=0.01). Fetal growth restriction was associated with anti-phospholipid antibodies (p<0.01). Early onset preeclampsia was associated with anti-phospholipid antibodies (p=0.01). Extensive placental infarction (>10%) was associated with anti-phospholipid antibodies (p<0.01). Low placental weight (<5th percentile) was associated with hyperhomocysteineamia (p=0.03). No other associations were observed.

CONCLUSIONS

Early onset preeclampsia, especially if complicated by fetal growth restriction, are associated with anti-phospholipid antibodies. Other phenotypes of preeclampsia, especially HELLP syndrome, were not associated with thrombophilia. We advise only to test for anti-phospholipid antibodies after early onset preeclampsia, especially if complicated by fetal growth restriction. We suggest enough evidence is presented to justify no further studies are needed.

Ruptured intracranial aneurysm during pregnancy with false-negative computed tomography angiography findings: a case report

A 34-year-old female was admitted at 34 weeks of gestation with sudden onset of a severe headache accompanied by vomiting. Neurological examination revealed neck rigidity, and computed tomography (CT) of the brain revealed a subarachnoid hemorrhage (SAH). Although the hemorrhage was located primarily in the left Sylvian fissure, computed tomography angiography (CTA) performed immediately after CT did not reveal any obvious vascular abnormalities such as an intracranial aneurysm. An emergency cesarean section was performed, and a healthy infant was delivered. Cerebral digital subtraction angiography (DSA) was performed the day following surgery, which revealed a saccular aneurysm measuring 4.3 mm × 2.4 mm in the left middle cerebral artery. Left craniotomy and clipping of the aneurysm were performed. The clot around the aneurysm was relatively solid. This case report is of significance given that initial CTA was negative for SAH during pregnancy, suggesting the requirement for immediate DSA or another CTA in such cases. There are many previous reports on false-negative CTA findings or disappearance and reappearance of aneurysms in SAH patients, and various biophysical and dynamic parameters are suggested to cause such phenomena. However, there are no reports on similar occurrences during pregnancy. Although the precise cause remains unclear, multiple factors associated with homeostasis during pregnancy were possibly associated with the transient disappearance in this patient.

Pregnancy and vascular liver disease

Vascular disorders of the liver frequently affect women of childbearing age. Pregnancy and the postpartum are prothrombotic states. Pregnancy seems to be a trigger for Budd-Chiari syndrome in patients with an underlying prothrombotic disorder. Whether pregnancy is a risk factor for other vascular liver disorders is unknown. In women with a known vascular liver disorder and a desire for pregnancy, stabilisation of the liver disease, including the use of a portal decompressive procedure when indicated, should be reached prior to conception. The presence of esophageal varices should be screened and adequate prophylaxis of bleeding applied in a manner similar to what is recommended for patients with cirrhosis. Most women likely benefit from anticoagulation during pregnancy and the postpartum. Labor and delivery are best managed by a multidisciplinary team with experience in this situation. Assisted vaginal delivery is the preferred mode of delivery. Although the risk of miscarriage and premature birth is heightened, current management of these diseases makes it very likely to see the birth of a live baby when pregnancy reaches 20 weeks of gestation.

The hypercoagulable states in anaesthesia and critical care

Hypercoagulable disorders are now diagnosed more frequently than before. These patients are, usually, managed with multiple anticoagulant and antiplatelet medications. Left unmonitored and unevaluated, there can be disastrous haemorrhagic or thrombotic complications. Appropriate perioperative and anaesthetic management of these patients will invite an aetiological diagnosis, severity analysis and the on-going treatment review. Different assays, thromboelastography and molecular cytogenetics have helped to diagnose these conditions precisely and thus guide the long-term management. Besides this, there are varieties of clinical conditions that will predispose to the hypercoagulability. These need to be defined and classified in order to offer a suitable therapeutic option. Pregnancy is one such important condition and can have more than one responsible factor favouring hypercoagulability. With such diverse kinds of disorders, it would be essential to note the anaesthetic implications, to avoid adverse perioperative outcomes. Available evidence based guidelines will help to make the therapeutic approach more precise. Selection of the appropriate technique of anaesthesia, offering the appropriate anticoagulation bridging as necessary and defining an appropriate interval and time for the intervention will help to minimise the complications.

Overview of the coagulation system

Coagulation is a dynamic process and the understanding of the blood coagulation system has evolved over the recent years in anaesthetic practice. Although the traditional classification of the coagulation system into extrinsic and intrinsic pathway is still valid, the newer insights into coagulation provide more authentic description of the same. Normal coagulation pathway represents a balance between the pro coagulant pathway that is responsible for clot formation and the mechanisms that inhibit the same beyond the injury site. Imbalance of the coagulation system may occur in the perioperative period or during critical illness, which may be secondary to numerous factors leading to a tendency of either thrombosis or bleeding. A systematic search of literature on PubMed with MeSH terms ‘coagulation system, haemostasis and anaesthesia revealed twenty eight related clinical trials and review articles in last 10 years. Since the balance of the coagulation system may tilt towards bleeding and thrombosis in many situations, it is mandatory for the clinicians to understand physiologic basis of haemostasis in order to diagnose and manage the abnormalities of the coagulation process and to interpret the diagnostic tests done for the same.

QCM-D providing new horizon in the domain of sensitivity range and information for haemostasis of human plasma

Monitoring of the haemostasis status is significant for proper therapeutic directions and decisions in surgery and innate coagulation disorders. In this regard, to gain a general overview of the plasmatic coagulation, prothrombin time (PT) tests are frequently combined with tests for activated partial thromboplastin time (aPTT). For aPTT we report for the first time that a QCM-D (Quartz Crystal Microbalances with Dissipation) based technique offers a better alternative to the standard coagulometer method in the perspective of range and information. We used heparin as anticoagulant to generate different coagulation times for human plasma. QCM-D astonishingly proved to be more sensitive and reliable than the standard coagulometer for aPTT range of upper limits of coagulation times. The established platform can monitor the fibrinogen concentration ranging from 1-6g/L (yielding R(2)=0.98 in calibration curves) along with aPTT from frequency and dissipation shifts together in a single set of measurements. Additionally the sensor layers have been tested for reusability, demonstrating no loss in sensor characteristics up to ten times measurements.

Exploring ethical conflicts in emergency trauma research: the COMBAT (Control of Major Bleeding after Trauma) study experience

BACKGROUND

Up to 25% of severely injured patients develop trauma-induced coagulopathy. To study interventions for this vulnerable population for whom consent cannot be obtained easily, the Food and Drug Administration issued regulations for emergency research with an exception from informed consent (ER-EIC). We describe the community consultation and public disclosure (CC/PD) process in preparation for an ER-EIC study, namely the Control Of Major Bleeding After Trauma (COMBAT) study.

METHODS

The CC/PD was guided by the four bioethical principles. We used a multimedia approach, including one-way communications (newspaper ads, brochures, television, radio, and web) and two-way communications (interactive in-person presentations at community meetings, printed and online feedback forms) to reach the trials catchment area (Denver County's population: 643,000 and the Denver larger metro area where commuters reside: 2.9 million). Particular attention was given to special-interests groups (eg, Jehovah Witnesses, homeless) and to Spanish-speaking communities (brochures and presentations in Spanish). Opt-out materials were available during on-site presentations or via the COMBAT study website.

RESULTS

A total of 227 community organizations were contacted. Brochures were distributed to 11 medical clinics and 3 homeless shelters. The multimedia campaign had the potential to reach an estimated audience of 1.5 million individuals in large metro Denver area, the majority via one-way communication and 1900 in two-way communications. This resource intensive process cost more than $84,000.

CONCLUSION

The CC/PD process is resource-intensive, costly, and complex. Although the multimedia CC/PD reached a large audience, the effectiveness of this process remains elusive. The templates can be helpful to similar ER-EIC studies.

Anaesthesia for Caesarean Section of Pregnant Women with Idiopathic Thrombocytopenic Purpura

Women with idiopathic thrombocytopenic purpura (ITP) may become pregnant, or the disease may occur for the first time during pregnancy. Thrombocytopenia is usually noticed in the first months of pregnancy and the platelet count is often quite low. In this case report, we described the anaesthetic method for caesarean section in a pregnant woman at 38 weeks of gestation with refractory ITP.

The use of thrombolytic therapy in pregnancy

The relative hypercoagulable state of pregnancy leads to an increased risk of thrombotic complications, of which some may be life-threatening or medically devastating. In the non-pregnant patient, the current guidelines suggest thrombolysis as the primary treatment in acute ischemic stroke, myocardial infarction when percutaneous intervention is unavailable, certain cases of mechanical valve thrombosis, and pulmonary embolism with hemodynamic compromise or shock. Given that clinical trial data regarding thrombolytic use in pregnant women are absent due to exclusion, the goal of this review is to summarize the available published data regarding the use of thrombolytic agents and subsequent outcomes and complications in pregnant women. Overall, the use of thrombolytic agents in pregnancy is associated with a relatively low reported complication rate, especially given the severe medical conditions for which they are indicated. The data would suggest that thrombolysis should be considered for appropriate indications similar to that of non-pregnant patients. However, caution should be exercised when drawing conclusions regarding maternal and fetal safety, given the lack of controlled clinical trials including pregnant women and the nature of the weak evidence level of the cumulative data presented in this review.

Protein Z, an anticoagulant protein with expanding role in reproductive biology

Protein Z (PZ) is a vitamin K-dependent factor characterized by its homology to other vitamin K-dependent factors (factors VII, IX, and X, protein C and protein S), but lacks any enzymatic activity. Instead, PZ acts as a cofactor for the inhibition of factor Xa through the serpin PZ-dependent protease inhibitor (ZPI). PZ deficiency is associated with a procoagulant state, highlighted by excessive FXa secretion and thrombin production, and is linked with several thrombotic disorders, including arterial vascular and venous thromboembolic diseases. A role for the PZ-ZPI complex in the regulation of physiological pregnancy has been demonstrated, highlighted by the progressive elevation in PZ levels in the first trimester of gestation, which then steadily decline toward delivery. An association between altered plasma PZ concentrations and adverse pregnancy outcomes (recurrent miscarriage, stillbirth, preeclampsia, intrauterine growth restriction, and placental abruption) has been reported. The mechanism by which PZ deficiency leads to adverse pregnancy outcomes is not clear, but it is multifactorial. It may be attributed to the anti-PZ IgG and IgM autoantibodies, which apparently act independently of classical antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, and anti-β2-glycoprotein I antibodies). PZ deficiency has also been reported to be constitutional, and a number of variants in the PROZ (PZ) gene and SERPINA10 (ZPI) gene are linked with specific adverse pregnancy complications. This review summarizes the relationship between adverse pregnancy outcomes and acquired and constitutional PZ-ZPI deficiency, in order to understand whether or not PZ deficiency could be considered as a risk factor for poor pregnancy outcomes.

Hemostatic disorders in women

The past few decades have seen major advances in multidisciplinary obstetric care and management of gynecological conditions in women with bleeding disorders. Awareness of the impact of bleeding disorders has improved among the obstetric and gynecological community. Undiagnosed bleeding disorders can be the underlying cause for a significant proportion of women with heavy menstrual bleeding. They may also be the cause or a contributory factor for other gynecological problems, such as dysmenorrhea, intermenstrual bleeding, and endometriosis. Hemostatic assessment should be considered in women referred for menstrual abnormalities if they have a positive bleeding history as quantified by bleeding assessment tools. The reproductive choices and options for prenatal diagnosis are also expanding for families with hemophilia with a drive toward achieving a non-invasive approach. Current non-invasive prenatal diagnostic techniques are limited to identification of fetal gender. Research is ongoing to overcome the specific diagnostic challenges of identifying hemophilia mutations, utilizing free fetal DNA circulating in maternal plasma. The management of obstetric hemorrhage has recently evolved to include a greater focus on the identification of and early treatment for coagulation disorders. Deficiencies in certain hemostatic variables are associated with progression to more severe bleeding; therefore, specific interventions have been proposed to target this. Evidence is still lacking to support such strategy, and future research is required to assess the efficacy and the safety of these hemostatic interventions in women with persistent PPH.

Fertility and pregnancy in women affected by glycogen storage disease type I, results of a multicenter Italian study

BACKGROUND

Life expectancy of patients with glycogen storage disease (GSD) type I has improved considerably, opening new problems correlated with adult age. In females polycystic ovaries (PCOs) has been described as frequently associated with the disease, however successful pregnancies have been reported. Whether or not GSD I is associated with impaired reproductive function is still unclear.

PATIENTS AND METHODS

Data about female patients with GSD Ia and Ib, who were 16 years or older, were obtained from clinical records and interviews.

RESULTS

A total of 32 women with GSD I (25 GSD Ia, 7 GSD Ib), median age 26 years (range 16-55), were included. 9/32 patients had delayed menarche, 17/32 had irregular cycles, 8/22 had documented polycystic ovaries. Five successful spontaneous pregnancies in four patients with GSD Ia and two in a woman with GSD Ib were reported. The latter had development and enlargement of hepatic adenomas during pregnancies.

CONCLUSION

Despite the high prevalence of irregular menstruation cycles and polycystic ovaries, fertility seems not to be impaired in women with GSD I. During pregnancy monitoring for adenoma development is mandatory.

Endogenous oestradiol as a positive correlate of plasma fibrinogen among older postmenopausal women: a population-based study (the Three-City cohort study)

BACKGROUND

Plasma fibrinogen is a strong predictor of ischaemic arterial disease in women. Sex steroid hormones including hormone therapy may play an important role in the development of cardiovascular disease. However, whether endogenous sex steroid hormones influence the plasma fibrinogen concentrations among postmenopausal women remains unclear.

OBJECTIVES

To investigate the association of plasma fibrinogen levels with endogenous sex steroid hormones and sex hormone binding globulin (SHBG) among postmenopausal women.

METHODS

We used data from the French prospective Three-City cohort study that included 9294 noninstitutionalized men and women over 65 years of age. Total 17β-oestradiol (E2, pg/ml), total testosterone (T, ng/ml), SHBG (nm) and fibrinogen (g/l) were measured in stored plasmas in a subcohort of 602 randomly selected postmenopausal women who used neither hormone medication nor anticoagulation therapy. Multivariate linear regression models were used to estimate the regression coefficients assessed in fibrinogen unit by 1 SD increase in log-distribution of sex steroid hormones and SHBG.

RESULTS

E2 but neither T nor SHBG was positively associated with plasma fibrinogen levels (β = 0·148, P < 0·001). Adjustment for cardiovascular risk factors including diabetes made no substantial change to the results (β = 0·145, P < 0·001). The association of fibrinogen with E2 was stronger among women with body mass index over 25 kg/m(2) compared with those with normal weight (β = 0·156, P < 0·001 and β = 0·092, P = 0·02, respectively, P for interaction = 0·04).

CONCLUSION

E2 emerges as a positive and independent correlate of plasma fibrinogen among postmenopausal women, especially in subjects who are overweight. These findings suggest a deleterious effect of endogenous oestrogens on cardiovascular risk profile among postmenopausal women.

Evaluation of coagulation abnormalities among women with vaginal bleeding in the first trimester of pregnancy

OBJECTIVE

To compare blood coagulation parameters between pregnant women with vaginal bleeding in the first trimester of pregnancy and pregnant women with normal pregnancy in the first trimester.

METHODS

A prospective controlled study of 98 women in the first trimester of vital pregnancy was conducted at the University Medical Centre Maribor, Slovenia. The study group comprised women with vaginal bleeding (n=50) while the control group women with normal pregnancy, admitted for artificial abortion (n=48). Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration, number of platelets, hemogram, coagulation factor VIII (FVIII) and von Willebrand factor (VWF) activity were compared between the 2 groups.

RESULTS

No significant between-group differences were detected in mean PT, fibrinogen concentration, FVIII, and VWF activity. Mean aPTT was significantly higher in the control group than the study group (32.47 versus 30.46 seconds; P<0.05). The mean number of platelets was significantly lower in the study group than the control group (181.69 versus 203.52×10(9)/L; P<0.05). All measured coagulation parameters, except VWF activity, were within normal ranges.

CONCLUSION

Coagulation abnormalities are rarely the cause of vaginal bleeding in the first trimester of pregnancy among women with no previous symptoms of bleeding disorders.

Takayasus's arteritis in pregnancy. Case report and literature review

BACKGROUND AND OBJECTIVES

Takayasus's Arteritis (TA) is a chronic, inflammatory, progressive, idiopathic disease that causes narrowing, occlusion, and aneurysms of systemic and pulmonary arteries affecting especially the aorta and its branches. During pregnancy, one should pay special attention to these patients. The objective of this report was to present the peripartum anesthetic care of a patient with TA and a review of the literature.

CASE REPORT

This is a 31-year old gravida who underwent exchange of the aortic arch and placement of a metallic aortic valve for TA four years ago. She had no complications during pregnancy, and she was admitted at 34 weeks of pregnancy for anticoagulation management. Elective cesarean section was performed at 39 weeks with continuous epidural anesthesia. Fractionated doses of local anesthetic were administered to guarantee slow installation of the blockade. The patient remained hemodynamically stable and was transferred to the ICU in the postoperative period.

CONCLUSIONS

Several complications can affect gravidas with TA. Careful patient evaluation, treatment of TA complications, and anestheticsurgical planning are fundamental. Maintenance of perfusion is the main concern in these patients, and neuraxial blocks may be used without harming the mother and fetus. In patients with compensated TA complications, monitoring does not differ from that routinely used in cesarean sections. Continuous epidural anesthesia with slow installation maintains hemodynamic stability and allows monitoring cerebral perfusion through the level of consciousness. To avoid postoperative hypoperfusion or hypertensive complications patients should be monitored in an intensive or semi-intensive care unit for 24 hours.

Association of the R67X and W303X non-sense polymorphisms in the protein Z-dependent protease inhibitor gene with idiopathic recurrent miscarriage

Protein Z-dependent protease inhibitor (ZPI) is a 72 kDa single-chain serpin which inhibits the activated coagulation factors X and XI. Two non-sense polymorphisms of ZPI, R67X and W303X, were recently identified, and were linked with a prothrombotic state. Here, we investigated the association of the R67X (728C>T) and W303X (1438G>A) variants in the ZPI gene with recurrent spontaneous miscarriage (RSM). This was a case-control study involving a total of 288 women with a history of two consecutive or ≥3 non-consecutive pregnancy losses between 8 and 12th week of gestation, along with 304 age-matched and ethnically matched multiparous control women, with no personal or family history of pregnancy complications. The minor allele frequency of R67X (P = 0.003) and W303X (P = 0.014) were higher in RSM cases than in control women. Both single-nucleotide polymorphisms were significantly associated with RSM under the dominant genetic association model, and were in moderate linkage disequilibrium (D' = 0.412; P < 0.001). Taking the common (728)C/(1438)G haplotype as reference, multivariate analysis confirmed the positive association of (728)T/(1438)G [P = 0.043; odds ratio (OR) = 2.25; 95% confidence interval (CI) = 1.03-4.90], and (728)T/(1438)A (P = 0.022; OR = 3.93; 95% CI = 1.23-12.59) haplotypes with increased RSM risk. These differences remained significant after controlling for some covariates. These results demonstrate that both ZPI R67X and W303X non-sense variants and specific ZPI haplotypes are significantly associated with RSM.

Is heparin a placental anticoagulant in high-risk pregnancies?

Randomized control trials show beneficial effects of heparin in high-risk pregnancies to prevent preeclampsia and intrauterine growth restriction. However, the lack of placental pathology data in these trials challenges the assumption that heparin is a placental anticoagulant. Recent data show that placental infarction is probably associated with abnormalities in development of the placenta, characterized by poor maternal perfusion and an abnormal villous trophoblast compartment in contact with maternal blood, than with maternal thrombophilia. At-risk pregnancies may therefore be predicted by noninvasive prenatal testing of placental function in mid-pregnancy. Heparin has diverse cellular functions that include direct actions on the trophoblast. Dissecting the non-anticoagulant actions of heparin may indicate novel and safer therapeutic targets to prevent the major placental complications of pregnancy.