Prevention and Treatment of Venous Thromboembolism in Pregnancy

Case-based discussion on the implications of exogenous estrogens in hemostasis and thrombosis: the obstetrician's view

This is the obstetrician's view on 3 different clinical scenarios involving bleeding and thrombotic disorders. In the first scenario, an 18 year old with a history of heavy menstrual bleeding since menarche presents with abdominal pain and ultrasound findings suggestive of a hemorrhagic ovarian cyst. The association with an underlying bleeding disorder is recognized. The goals of management, which are controlling hemorrhage and preserving fertility, are stated. Ovarian suppression, the most effective method to prevent recurrent hemorrhagic ovarian cysts, is outlined. Long-term management of heavy menstrual bleeding with hormonal contraception is described. In the second scenario, the same patient returns 5 years later for a preconception visit. The potential risks to an unborn baby with von Willebrand disease (VWD) are addressed. The natural rise in von Willebrand factor (VWF) during pregnancy is discussed, but the fact that women with VWD do not achieve the same VWF levels as women without VWD is emphasized and the implications are presented. In anticipation of pregnancy, the need for nonhormonal management of heavy menstrual bleeding and hemorrhagic ovarian cysts is mentioned. In the third and final scenario, the patient's cousin with factor V Leiden seeks consultation regarding the risks of thrombosis with in vitro fertilization. The steps of assisted reproductive technology are described. The strategies to prevent venous thromboembolism by preventing ovarian hyperstimulation and reducing the likelihood of multiple gestation are detailed.

Obstetric and neonatal outcomes in pregnant women treated with high-dose thromboprophylaxis: a retrospective, single-center study

INTRODUCTION

It is well established that women with very high risk of developing antenatal thrombosis benefit from high-dose thromboprophylaxis, however data on outcomes and the safety and efficacy of thromboprophylaxis are scarce. The aim of the study was to evaluate the safety and effectiveness of the Swedish guidelines for high-dose thromboprophylaxis and the obstetric outcomes in a single-center patient cohort.

PATIENTS AND METHODS

Forty-seven women treated at the Department of Obstetrics and Gynecology, Karolinska University Hospital, Solna, Sweden, between 2004 and 2017 were included in this retrospective study. Data on treatment, obstetric, and neonatal outcomes and medical history were collected. Data derived from the Swedish Medical Birth Registry on women giving birth in Stockholm County 2004-2016 were used as controls. The protocol of the study was approved by the Regional Ethics Committee in Stockholm, Sweden.

RESULTS

The initial thromboprophylaxis dose was 5000 IU dalteparin twice daily. No patient developed ablatio placentae or preeclampsia. One patient suffered antenatal muscle vein thrombosis. Six patients (12.7%) suffered postpartum hemorrhage (PPH); however only one patient had severe PPH. Forty-eight children were born. Three children (6%) were diagnosed with intrauterine growth retardation, five (10%) were born small for gestational age and seven (15%) were born premature, the majority of which (except for two premature) to women with thrombophilia.

DISCUSSION

High-dose thromboprophylaxis was effective and safe. The incidence of preeclampsia and ablatio was lower than in controls; however, neonatal outcomes were worse, especially among mothers with thrombophilia. Due to the diversity of the thrombophilic traits, no thrombophilia-specific conclusion could be drawn. Stricter adherence to the guidelines could further decrease the risk for bleeding, whereas more frequent antenatal controls could possible improve neonatal outcomes.

Quality Improvement Opportunities Identified Through Case Review of Pregnancy-Related Deaths From Venous Thromboembolism

OBJECTIVE

To analyze quality improvement opportunities (QIOs) identified through review of cases of maternal death from venous thromboembolism (VTE) by the California Pregnancy-Associated Mortality Review Committee.

DESIGN

Qualitative, descriptive design using thematic analysis.

SAMPLE

A total of 108 QIOs identified from 29 cases of pregnancy-related deaths from VTE in California from 2002 to 2007.

METHODS

We coded and thematically organized the 108 QIOs using three of the four domains commonly applied in quality improvement initiatives for maternal health care: Readiness, Recognition, and Response. Data did not include reporting issues, so the Reporting domain was excluded from the analysis.

RESULTS

Women's lack of awareness of the significance of severe VTE symptoms and the lack of a standardized approach to recognize and respond to VTE signs and symptoms were the most prevalent themes in the Readiness domain. Missing the signs and symptoms of VTE and the resultant missed or delayed diagnosis were predominant themes in the Recognition domain. For Response, issues related to lack of VTE prophylaxis were most frequently noted, along with other themes, including timing of treatment and appropriate follow-up after hospital discharge.

CONCLUSION

To decrease the occurrence of maternal death from VTE in the United States, consistent and thorough education regarding VTE signs and symptoms must be given to all women and their families during pregnancy and the postpartum period. Maternity care facilities and providers should implement preventive measures, including standardized use of VTE prophylaxis, improved methods to recognize the signs and symptoms of VTE, and improved follow-up after hospital discharge.

Large D-Dimer Fluctuation in Normal Pregnancy: A Longitudinal Cohort Study of 4,117 Samples from 714 Healthy Danish Women

Introduction. D-dimer levels increase throughout pregnancy, hampering the usefulness of the conventional threshold for dismissing thromboembolism. This study investigates the biological fluctuation of D-dimer in normal pregnancy. Methods. A total of 801 healthy women with expected normal pregnancies were recruited. D-dimer was repeatedly measured during pregnancy, at active labor, and on the first and second postpartum days. Percentiles for each gestational week were calculated. Each individual D-dimer was normalized by transformation into percentiles for the relevant gestational age or delivery group. The range in percentage points during the pregnancy and the delivery was calculated, and reference intervals were calculated for each pregnancy trimester, during vaginal delivery and scheduled and emergency cesarean section, and for the first and second day postpartum. Results. D-dimer increased during pregnancy; the maximal fluctuation was approximately 20 percentile points in approximately half of the women. In one out of ten women, the D-dimer values fluctuated by more than 50 percentile points. Conclusions. Due to the biological variation in D-dimer within each individual woman during normal pregnancy, repeated D-dimer measurements are of no clinical use in the evaluation of thromboembolic events during pregnancy.

Coagulation abnormalities of sickle cell disease: Relationship with clinical outcomes and the effect of disease modifying therapies

Sickle cell disease (SCD) is a hypercoagulable state. Patients exhibit increased platelet activation, high plasma levels of markers of thrombin generation, depletion of natural anticoagulant proteins, abnormal activation of the fibrinolytic system, and increased tissue factor expression, even in the non-crisis "steady state." Furthermore, SCD is characterized by an increased risk of thrombotic complications. The pathogenesis of coagulation activation in SCD appears to be multi-factorial, with contributions from ischemia-reperfusion injury and inflammation, hemolysis and nitric oxide deficiency, and increased sickle RBC phosphatidylserine expression. Recent studies in animal models suggest that activation of coagulation may contribute to the pathogenesis of SCD, but the data on the contribution of coagulation and platelet activation to SCD-related complications in humans are limited. Clinical trials of new generations of anticoagulants and antiplatelet agents, using a variety of clinical endpoints are warranted.

Sickle cell disease and venous thromboembolism in pregnancy and the puerperium

Recent data strongly suggest an increased risk of venous thromboembolism in subjects with sickle cell disease and to a lesser extent, sickle cell trait. However, most studies have been retrospective, case-control or cross-sectional based on data obtained from administrative databases. More data from adequately powered prospective studies that include matched controls are needed to definitely establish the link between venous thromboembolism during pregnancy and sickle hemoglobin disorders. Similarly, there remains a need for properly designed randomized control trials to establish the safety of various hormonal contraceptive methods in women with sickle cell disorders.

Venous thromboembolism in pregnant women with sickle cell disease: a retrospective database analysis

INTRODUCTION

The risk of venous thromboembolism (VTE) is higher during pregnancy, with an incidence between 0.05 and 0.2%, and among persons with sickle cell disease (SCD), yet the rates and risk factors, such as pneumonia, vasooclusive crisis (VOC), and acute chest syndrome (ACS), associated with pregnancy-related VTE are not firmly established in SCD.

METHODS

Inpatient hospital discharge data from 2007-2011 were obtained from the Pennsylvania Health Care Cost Containment Council to estimate the rate of VTE among African American delivery hospitalizations with SCD and to compare pregnancy complications and medical comorbidities among pregnant women with SCD.

RESULTS

Among 212 hospitalized deliveries in African-American women with SCD, 6 (2.8%, 95% CI 1.0%-5.9%) had VTE compared to 0.05 to 2.0% in the general population. Risk factors for VTE included pneumonia and diabetes mellitus. Overall, the prevalence of VTE, among hospitalized deliveries in SCD women with pneumonia, VOC, and/or ACS, 6.6%, was significantly greater than among those without these conditions, 2.2%, p<0.001.

CONCLUSION

Pregnancy-related VTE in women with SCD appears to be 1.5 to 5 times greater than pregnancy-related VTE in the general population. The higher prevalence of VTE among pregnant women with pneumonia, VOC, and/or ACS, and their potential clinical overlap, suggests that VTE may be missed in such women. We conclude that VTE in pregnant women with SCD may be more common than previously reported, and such women might be candidates for thromboprophylaxis.

Pharmacological anti-thrombotic prophylaxis after elective caesarean delivery in thrombophilia unscreened women: should maternal age have a role in decision making?

In obstetrical practice, the best prevention strategy for pregnant women aged >35 years without known thrombosis risk factors who underwent elective caesarean delivery (CD) is controversial. We performed an observational-longitudinal cohort study on pregnant women aged >35 years who delivered at term by elective caesarean section after a physiological single pregnancy to evaluate the role of maternal age in the decision-making process of whether or not to perform low-molecular-weight heparin (LMWH) prophylaxis during the post-partum period after elective CD in healthy women with unknown inherited thrombophilia status. During the 6 post-partum weeks, we followed two groups: GROUP-A (349 women treated for 7 days with low-molecular-weight heparin) and GROUP-B (180 women not treated with LMWH treatment). The outcomes were as follows: onset of thromboembolic events during the post-partum period; non-obstetrical-linked maternal haemorrhage; blood transfusion; re-laparotomy; detection of a surgical site haematoma; length of hospitalisation; and treatment suspension because of decreased platelet count. Except for the parity number, the two groups were homogeneous with regard to general features. In both the groups, we reported no cases of thromboembolic events during the follow-up period. Maternal haemorrhage requiring transfusion occurred in 16 women in GROUP-A and none in GROUP-B. Among the GROUP-A women, 11 demonstrated a surgical site haematoma and 4 required re-laparotomy. No cases of treatment suspension were reported. Pneumatic compression stockings represent a better, low cost and safe way to prevent post-partum venous thromboembolic episodes after elective caesarean section in an unscreened population. Pharmacological prophylaxis after elective caesarean section should be performed only in case of clear and known adjunctive risk factors, independent of maternal age.

Postpartum wound and bleeding complications in women who received peripartum anticoagulation

INTRODUCTION

The objective of this study was to compare wound and bleeding complications between women who received anticoagulation after cesarean delivery due to history of prior venous thromboembolic disease, arterial disease, or being a thrombophilia carrier with adverse pregnancy outcome, to women not receiving anticoagulation.

METHODS

Women in the Duke Thrombosis Center Registry who underwent cesarean delivery during 2003-2011 and received postpartum anticoagulation (anticoagulation group, n=77), were compared with a subset of women who delivered during the same time period, but did not receive anticoagulation (no anticoagulation group, n=77). The no anticoagulation group comprised women who were matched to the anticoagulation group by age, body mass index, type of cesarean (no labor vs. labor), and date of delivery. Bleeding and wound complications were compared between the two groups. A multivariable logistic regression model was constructed to determine if anticoagulation was an independent predictor of wound complication.

RESULTS

Women who received anticoagulation during pregnancy had a greater incidence of wound complications compared to those who did not (30% vs. 8%, p<0.001). Using multivariable logistic regression, while controlling for race, diabetes, chorioamnionitis, and aspirin use, anticoagulation predicted the development of any wound complication (OR 5.8, 95% CI 2.2, 17.6), but there were no differences in the mean estimated blood loss at delivery (782 vs. 778 ml, p=0.91), change in postpartum hematocrit (5.4 vs. 5.2%, p=0.772), or percent of women receiving blood products (6.5 vs. 1.3%, p=0.209) between the two groups.

CONCLUSIONS

Anticoagulation following cesarean delivery is associated with an increased risk of post-cesarean wound complications, but not other postpartum bleeding complications.

[Peripartum cardiomyopathy: interdisciplinary challenge]

Peripartum cardiomyopathy (PPCM) is a rare type of heart failure which presents towards the end of pregnancy or in the first 5 months after delivery. Depending on the geographical location the incidence is reported in the literature as 1:300 up to 1:15,000. There are a number of known risk factors, such as multiparity and age of the mother over 30 years. The symptoms of PPCM correspond to those of idiopathic cardiomyopathy. The diagnosis is mainly carried out using echocardiography which shows a clear reduction of systolic left ventricular function. The therapeutic approach is the same as for idiopathic cardiomyopathy and in this context it is absolutely necessary to show caution concerning the state of pregnancy and the resulting contraindications for therapeutic drugs. The prognosis is dependent on recovery from the heart failure during the first 6 months postpartum. The lethality of the disease is high and is given in the literature as up to 28 %. Because of its complexity PPCM is an interdisciplinary challenge. In the peripartum phase a close cooperation between the disciplines of cardiology, cardiac surgery, neonatology, obstetrics and anesthesiology is indispensable. For anesthesiology the most important aspects are the mostly advanced unstable hemodynamic condition of the mother and the planning and implementation of the perioperative management. This article presents the case of a patient in advanced pregnancy with signs of acute severe heart failure and a suspected diagnosis of PPCM. The patient presented as an emergency case and delivery of the child was carried out using peridural anesthesia with a stand-by life support machine.

APPENDICITIS IN PREGNANCY

Acute appendicitis is the most common non-obstetric indication for surgical intervention in pregnancy, complicating 1/500 to 1/2000 deliveries. Due to the anatomical and physiological changes associated with pregnancy, appendicitis may present a diagnostic dilemma, leading to management delays and thus increasing the risk of appendiceal perforation. Many of the common presenting symptoms of appendicitis are common features of normal pregnancy including lower abdominal pain, nausea, vomiting and leukocytosis. Furthermore, the enlarging gravid uterus may displace the appendix to varying degrees thus altering the classic symptom pattern of appendicitis. The often nonspecific presentation in pregnancy may necessitate the utilization of diagnostic imaging to aid in accurate diagnosis. However, the perforated appendix is the most common surgical cause of fetal loss and the time required for any diagnostic aid must be weighed against the increasing risk of perforation caused by delay in surgical intervention.