Venous thromboembolism in pregnancy: 21-year trends

Axillary vein thrombosis 30 h after caesarean section: a case report and literature review

BACKGROUND

Axillary vein thrombosis is a very rare disorder. However, a case of axillary vein thrombosis shortly after caesarean section has not been reported previously. We report a case of axillary vein thrombosis 30 h after caesarean section due to an unidentified aetiology.

CASE

A 37-year-old multiparous woman developed swelling and pain of the forearm and hand 30 h after undergoing a caesarean section. Doppler ultrasonography revealed a 14.9 mm × 5.3 mm thrombosis in the left axillary vein although a prophylaxis of anticoagulation was administrated. After an adjusted-dose of low-molecular-weight heparin (LMWH) was administered, the patient recovered and was discharged.

CONCLUSION

Obstetricians should be fully aware of the possibility of upper extremity deep vein thrombosis (DVT) despite its rarity, especially after the surgery. Lying in the lateral decubitus position for long periods postoperatively should be avoided as much as possible.

Venous thromboembolism as a cause of severe maternal morbidity and mortality in the United States

In the U.S., deaths due to pulmonary embolism (PE) account for 9.2% of all pregnancy-related deaths or approximately 1.5 deaths per 100,000 live births. Maternal deaths and maternal morbidity due to PE are more common among women who deliver by cesarean section. In the past decade, the clinical community has increasingly adopted venous thromboembolism (VTE) guidelines and thromboprophylaxis recommendations for pregnant women. Although deep vein thrombosis rates have decreased during this time-period, PE rates have remained relatively unchanged in pregnancy hospitalizations and as a cause of maternal mortality. Changes in the health profile of women who become pregnant, particularly due to maternal age and co-morbidities, needs more attention to better understand the impact of VTE risk during pregnancy and the postpartum period.

Trends in venous thromboembolism among pregnancy-related hospitalizations, United States, 1994-2009

OBJECTIVE

The purpose of this study was to evaluate national trends in the rate of pregnancy-related hospitalizations for venous thromboembolism (VTE) from 1994-2009 and to estimate the prevalence of comorbid conditions among these hospitalizations.

STUDY DESIGN

An estimated 64,413,973 pregnancy-related hospitalizations among women 15-44 years old were identified in the 1994-2009 Nationwide Inpatient Sample. Trends in VTE-associated pregnancy hospitalizations were evaluated with the use of variance-weighted least squares regression. Chi-square tests were used to assess changes in prevalence of demographics and comorbid conditions, and multivariable logistic regression was used to evaluate the likelihood of VTE during the study period after adjustment for comorbid conditions. Antepartum, delivery, and postpartum hospitalizations were evaluated separately and reported in 4-year increments.

RESULTS

From 1994-2009, there was a 14% increase in the rate of overall VTE-associated pregnancy hospitalizations; antepartum and postpartum hospitalizations with VTE increased by 17% and 47%, respectively. Between 1994-1997 and 2006-2009, the prevalence of hypertension and obesity doubled among all VTE-associated pregnancy hospitalizations; significant increases in diabetes mellitus and heart disease were also noted. A temporal increase in the likelihood of a VTE diagnosis in pregnancy was observed for antepartum hospitalizations from 2006-2009 when compared with 1994-1997 (adjusted odds ratio, 1.62; 95% confidence interval, 1.48-1.78).

CONCLUSION

There has been an upward trend in VTE-associated pregnancy hospitalizations from 1994-2009 with concomitant increases in comorbid conditions. Clinicians should have a heightened awareness of the risk of VTE among pregnant women, particularly among those with comorbid conditions, and should have a low threshold for evaluation in women with symptoms or signs of VTE.

Sickle cell trait: is there an increased VTE risk in pregnancy and the postpartum?

Blacks are purported to have a higher venous thromboembolism (VTE) risk than whites. We hypothesized that this might be due, in part, to the greater presence of sickle cell trait (SCT) among blacks. We investigated whether the presence of SCT resulted in a higher VTE incidence in a population predisposed to VTE, the pregnant/postpartum women. Methods: Using a mirrored clinical database that prospectively gathered in- and out-patient information for the years 1998–2008, we collected demographic data, including hemoglobin electrophoreses, on all pregnant/postpartum non-Hispanic women who delivered at a large, diverse, urban hospital. We identified those women who developed VTE either while pregnant or postpartum during those 11 years. Charts initially identified as potential VTE cases were subjected to review to ensure accuracy of VTE coding. Results: Of 12,429 women, 679 non-Hispanic SCT black women, 5,465 non-Hispanic Hemoglobin AA (women with HbA as the only hemoglobin present on electrophoresis, with normal amounts of the minor hemoglobins) black women and 1,162 non-Hispanic HbAA white women were included in the analysis. SCT prevalence was high (11.1%) within this black population as compared to 8.3% in the general non-white population. Proportions with VTE were similar for black SCT and black HbAA groups: 0.44% for the SCT group, 0.49% for non-Hispanic black HbAA women. Black HbAA women had a non-significantly higher proportion of VTE than white HbAA women 0.49% vs 0.26% (RR 1.9, 95%CI:0.6,6.3, p = 0.28). Women with VTE were older than those without VTE (32.2 vs. 27.6 years, p = 0.0002) and the majority of VTE occurred postpartum in all groups, and significantly in the HbAA groups. There was no increase in the incidence of pulmonary emboli in the SCT group. Conclusion: In the largest analysis to date, we could not detect a meaningful difference in peripartum VTE incidence between women with and without sickle cell trait.

Epidemiology of pregnancy-associated venous thromboembolism: a population-based study in Canada

OBJECTIVE

To estimate the frequency of, and to identify risk factors for, pregnancy-associated venous thromboembolism (VTE), including deep vein thrombosis (DVT) and pulmonary embolism (PE) requiring hospitalization.

METHODS

We conducted a population-based cohort study (N = 3 852 569) using the Discharge Abstract Database of the Canadian Institute for Health Information (CIHI), for the fiscal years 1991-1992 to 2005-2006. All women with pregnancy-related hospitalizations in Canada (excluding Quebec and Manitoba) were identified. DVT and PE rates were calculated using the number of hospital deliveries (i.e., cohort of women at risk) as the denominator for the antepartum and peripartum (labour and delivery) hospitalizations and for postpartum readmissions. Risk factors for DVT/PE were identified using logistic regression.

RESULTS

During the antepartum, peripartum, and postpartum periods, 5.4, 7.2, and 4.3 VTE cases per 10,000 pregnancies, respectively were observed. The total incidence of DVT was 12.1 per 10,000 pregnancies (0.26 deaths per 100,000), and the rate for PE was 5.4 per 10,000 (0.96 deaths per 100,000). The strongest risk factors for DVT occurrence during the peripartum period were thrombophilia (adjusted odds ratio [aOR] 15.4; 95% CI 10.8-22.0), a past history of circulatory disease, and major puerperal infection, whereas those for PE were previous DVT (aOR 56.9; 95% CI 40.9-79.1), heart disease (aOR 43.4, 95% CI 35.0-53.9), antiphospholipid syndrome, past history of circulatory disease, transfusion, and major puerperal infection.

CONCLUSION

Cases of VTE and associated deaths occur most frequently during the peripartum period. Although mortality from pregnancy-associated VTE is low, maternal characteristics and other factors can be used to identify women at risk for VTE.

Trauma in pregnancy

Although serious trauma during pregnancy is uncommon, it remains a major cause of maternal and fetal death and presents a variety of patient care challenges. The anatomic and physiologic changes of pregnancy can affect both the nature of an injury and the body's response to it. Here, the author describes the mechanisms of traumatic injury during pregnancy, discusses the normal changes of pregnancy and their implications in the care of pregnant trauma patients, and offers strategies for assessment and treatment.

Venous thromboembolism in African-Americans: a literature-based commentary

Among the cardiovascular diseases and after ischemic heart disease and stroke, venous thromboembolism (VTE) is the third leading cause of death in the U.S. (3). Although VTE is seen across most ethnic groups in the U.S. as well as throughout the world, the rate varies. In the U.S., American Indians/Alaskan Natives as well as Asians have been reported to have a significantly lower rate of deep vein thrombosis (DVT) and pulmonary embolism (PE) as compared to blacks and whites. In sharp conrast blacks appear to have much higher rates than whites. Although these rate differences are thought in part by some to be attributable to disparities in diagnosis and care as well as genetics, it nevertheless is important to define as well as to understand the true incidence and impact so that both public health and clinical resources can be maximally utilized. The purpose of this commentary is to review the VTE burden in the U.S. with respect to ethnicity in terms of clinical demographics and genetics with particular emphasis on blacks.

Thrombophilia risk factors are associated with intrauterine foetal death and pregnancy-related venous thromboembolism

Pregnancy in healthy women is accompanied by hypercoagulable changes that may interact with thrombophilia risk factors and threaten pregnancy. However, the literature on this issue is conflicting. In investigating the relationship between pregnancy-associated complications and the presence of thrombophilia risk factors, we studied the records of 414 women who had been examined for inherited and acquired thrombophilia in the period 1996 to 2006 because of pregnancy-associated complications. Of a total of 885 pregnancies among the women, 397 were recorded as foetal loss/intrauterine foetal death during the first (62 %), second (25 %) or third trimester (13 %). One-hundred-and-two (25 %) women had had a thromboembolic event during one of their pregnancies, and 98 (24 %) had had pre-eclampsia on at least one occasion. Intrauterine growth restriction was found in 105 (25 %) of the women, and 29 (7 %) suffered placental abruption. We found that 120 (29 %) women had at least one thrombophilia risk factor. Factor V Leiden heterozygosity was the most common thrombophilia factor (n = 52), mostly linked with the risk of venous thromboembolism during pregnancy or postpartum and to foetal death during the second or third trimester. Fifty-three (13 %) women had antiphospholipid antibodies (lupus anticoagulant and/or anti-beta2-glycoprotein 1 antibodies) mainly associated with the risk of spontaneous abortion during the first trimester. In conclusion, thrombophilia was found to be considerably more common in women with pregnancy-associated complications in comparison with the general population, and most frequently in conjunction with venous thromboembolism during pregnancy and the postpartum period.

Venous thromboembolism in women

Abstract

The risk of venous thromboembolism (VTE) varies throughout a woman’s life and is associated primarily with underlying hormonal exposure. Alteration in hemostatic mechanisms, including resistance to activated protein C, may explain this altered risk. Initially, development of VTE with the use of contraception in young adulthood may reveal inherited thrombophilia. Pregnancy, and particularly the post-partum period, likely confer the greatest risk of VTE, but the absolute risk is small. Guidelines for prevention of VTE during pregnancy are based on personal or family history of VTE, and known inherited thrombophilia. Use of hormone replacement therapy later in life is associated with increased risk of VTE, and may be safest if given as an estrogen-only preparation to young postmenopausal women for less than 5 years. Universal screening for thrombophilia prior to pregnancy or initiating hormonal therapy is not recommended; however, selected testing in high-risk groups may be warranted. The lack of firm recommendations for the prevention of VTE in women highlights the need for future investigation aimed at identifying high-risk groups and evaluating the efficacy of prophylactic measures.

Critical care of the obstetric patient

The obstetric patient poses exceptional challenges in the intensive care unit. Knowledge of the physiologic changes of pregnancy and specific pregnancy-related disorders is necessary for optimal management. Intensive care unit diagnoses may include preeclampsia, including the HELLP syndrome, pulmonary embolic disease, amniotic fluid embolism, status asthmaticus, respiratory infection, the acute respiratory distress syndrome, and sepsis. The management of mechanical ventilation is based on principles of avoiding lung injury, and hypercapnia may be tolerated even during the pregnancy. When the clinician is faced with the extraordinary instance of cardiopulmonary arrest, perimortem cesarean delivery must be considered to improve the potential for maternal and fetal survival.

Association between adverse pregnancy outcomes and maternal factor V G1691A (Leiden) and prothrombin G20210A genotypes in women with a history of recurrent idiopathic miscarriages

Thrombophilia was implicated in the development of pregnancy complications, including recurrent idiopathic pregnancy loss, and is aggravated in women who are carriers of factor V G1691A (FV Leiden) and prothrombin (PRT) G20210A single-nucleotide polymorphisms (SNPs). Previous studies examined the role of FV-Leiden and PRT G20210A in recurrent pregnancy loss with conflicting results. Here we examined the prevalence of FV Leiden and PRT G20210A SNPs, in 200 women with 3 or more consecutive early (n = 87), late (n = 41), or early-late (n = 72) recurrent pregnancy losses, and 200 age-matched fertile parous control women. APC resistance (APCR) was detected functionally (measuring the activated clotting time triggered by activated factor X in presence of a fixed amount of purified APC), and FV-Leiden and PRT G20210A genotypes were assessed by PCR. The frequency of the mutant FV (0.1400 vs. 0.0276; P < 0.001) but not PRT 20210 (0.0100 vs. 0.0225; P = 0.159) allele was higher in patients than controls, respectively. APC resistance with factor V Leiden was seen in 27% of patients compared to 11.5% of controls, while APC resistance without factor V Leiden was seen in 12.5% of patients compared to 9.5% of controls. Regression analysis demonstrated that the significant predictors for early abortion was FV Leiden; those for late abortion were oral contraceptive, APCR, and FV Leiden; and predictors for early-late abortions were oral contraceptives, obesity, FV Leiden, and smoking. APC resistance and FV Leiden, as well as combination of both, are common thrombotic defects seen in women with idiopathic recurrent pregnancy loss, thus testing for these is recommended in women who have experienced recurrent miscarriages.