A randomized controlled trial of differing doses of postcesarean enoxaparin thromboprophylaxis in obese women

Peripartum interventions for people with class III obesity: a systematic review and meta-analysis

OBJECTIVE

This study aimed to identify evidence-based peripartum interventions for people with a body mass index ≥40 kg/m2.

DATA SOURCES

PubMed, MEDLINE, EMBASE, Cochrane, CINAHL, and ClinicalTrials.gov were searched from inception to 2022 without date, publication type, or language restrictions.

STUDY ELIGIBILITY CRITERIA

Cohort and randomized controlled trials that implemented an intervention and evaluated peripartum outcomes of people with a body mass index ≥40 kg/m2 were included. The primary outcome depended on the intervention but was commonly related to wound morbidity after cesarean delivery (ie, infection, separation, hematoma).

METHODS

Meta-analysis was completed for interventions with at least 2 studies. Pooled risk ratios with 95% confidence intervals and heterogeneity (I2 statistics) were reported.

RESULTS

Of 20,301 studies screened, 30 studies (17 cohort and 13 randomized controlled trials) encompassing 10 types of interventions were included. The interventions included delivery planning (induction of labor, planned cesarean delivery), antibiotics during labor induction or for surgical prophylaxis, 6 types of cesarean delivery techniques, and anticoagulation dosing after a cesarean delivery. Planned cesarean delivery compared with planned vaginal delivery did not improve outcomes according to 3 cohort studies. One cohort study compared 3 g with 2 g of cephazolin prophylaxis for cesarean delivery and found no differences in surgical site infections. According to 3 cohort studies and 2 randomized controlled trials, there was no improvement in outcomes with a non-low transverse skin incision. Ten studies (4 cohort and 6 randomized controlled trials) met the inclusion criteria for the meta-analysis. Two randomized controlled trials compared subcuticular closure with suture vs staples after cesarean delivery and found no differences in wound morbidity within 6 weeks of cesarean delivery (n=422; risk ratio, 1.09; 95% confidence interval, 0.75-1.59; I2=9%). Prophylactic negative-pressure wound therapy was compared with standard dressing in 4 cohort and 4 randomized controlled trials, which found no differences in wound morbidity (cohort n=2200; risk ratio, 1.19; 95% confidence interval, 0.88-1.63; I2=66.1%) or surgical site infections (randomized controlled trial n=1262; risk ratio, 0.90; 95% confidence interval, 0.63-1.29; I2=0).

CONCLUSION

Few studies address interventions in people with a body mass index ≥40 kg/m2, and most studies did not demonstrate a benefit. Either staples or suture are recommended for subcuticular closure, but available data do not support prophylactic negative-pressure wound therapy after cesarean delivery for people with a body mass index ≥40 kg/m2.

Comparison of postpartum anti-Xa levels following enoxaparin administration to prevent venous thromboembolism using 2 weight-based protocols: a randomized controlled trial

BACKGROUND

During the postpartum period, enoxaparin is given to high-risk women to prevent venous thromboembolism, a leading cause of maternal mortality. Enoxaparin activity is measured by peak plasma anti-Xa levels. The prophylactic range of anti-Xa is 0.2 to 0.6 IU/mL. Values above and below this range represent subprophylactic and supraprophylactic levels, respectively. Weight-based enoxaparin administration was superior to fixed-dose enoxaparin administration in achieving an anti-Xa prophylactic range. However, it is unknown which weight-based enoxaparin administration is superior (once daily weight categories vs 1 mg/kg body weight).

OBJECTIVE

This study aimed to compare the efficacy in reaching prophylactic anti-Xa levels and adverse effects profile of the 2 weight-based enoxaparin dosing protocols.

STUDY DESIGN

A randomized open-label controlled trial was conducted. Women after delivery, who were intended to receive enoxaparin, were randomized to receive either enoxaparin treatment according to 1 mg/kg (up to 100 mg) or weight categories (≤90 kg, 40 mg; 91-130 kg, 60 mg; 131-170 kg, 80 mg; >170 kg, 100 mg). Plasma anti-Xa levels were obtained 4 hours after the second enoxaparin administration (day 2 of enoxaparin treatment). If the woman was still hospitalized, anti-Xa levels were also obtained on day 4. The primary endpoint was the proportion of women with anti-Xa levels within the prophylactic range at day 2. In addition, data regarding anti-Xa levels in different weight groups and rates of venous thromboembolism and adverse effects were evaluated.

RESULTS

Of note, 60 and 64 women received enoxaparin according to 1 mg/kg and weight categories, respectively; moreover, 55 (92%) and 27 (42%) women reached the prophylactic range of anti-Xa at day 2, respectively (P<.0001). The mean anti-Xa levels on day 2 were 0.34±0.09 and 0.19±0.06 IU/mL, respectively (P<.0001). The anti-Xa levels were higher in the 1 mg/kg group than in the weight categories group in the subanalysis of different weight categories (51-70, 71-90, and 91-130 kg). There was no difference in anti-Xa levels on day 4 compared with day 2 in both cohorts (n=25). There was no case of supraprophylactic anti-Xa levels, venous thromboembolism events, or serious hemorrhage.

CONCLUSION

Postpartum enoxaparin administration at 1 mg/kg was superior to weight categories in reaching anti-Xa prophylactic levels without leading to serious adverse effects. Given the high efficacy and safety profile, enoxaparin at 1 mg/kg once daily should be considered the preferred protocol for postpartum venous thromboembolism prophylaxis.

Pregnancy in women with congenital heart disease: a focus on management and preventing the risk of complications

INTRODUCTION

Congenital heart disease (CHD) is the most common cardiac disorder in pregnancy in the western world (around 80%). Due to improvements in surgical interventions more women with CHD are surviving to adulthood and choosing to become pregnant.

AREAS COVERED

Preconception counseling, antenatal management of CHDs and strategies to prevent maternal and fetal complications.Preconception counseling should start early, before the transition to adult care and be offered to both men and women. It should include the choice of contraception, lifestyle modifications, pre-pregnancy optimization of cardiac state, the chance of the child inheriting a similar cardiac lesion, the risks to the mother, and long-term prognosis. Pregnancy induces marked physiological changes in the cardiovascular system that may precipitate cardiac complications. Risk stratification is based on the underlying cardiac disease and data from studies including CARPREG, ZAHARA, and ROPAC.

EXPERT OPINION

Women with left to right shunts, regurgitant lesions, and most corrected CHDs are at lower risk and can be managed in secondary care. Complex CHD, including systemic right ventricle need expert counseling in a tertiary center. Those with severe stenotic lesions, pulmonary artery hypertension, and Eisenmenger's syndrome should avoid pregnancy, be given effective contraception and managed in a tertiary center if pregnancy does happen.

Weight-Based Compared With Fixed-Dose Enoxaparin Prophylaxis After Cesarean Delivery: A Randomized Controlled Trial

OBJECTIVE

To evaluate fixed compared with weight-based enoxaparin dosing to achieve prophylactic anti-Xa levels after cesarean delivery.

METHODS

Individuals meeting institutional criteria for enoxaparin thromboprophylaxis after cesarean delivery were randomly allocated to fixed (40 mg daily for body mass index [BMI, calculated as weight in kilograms divided by height in meters squared] lower than 40; 40 mg every 12 hours for BMI 40 or higher) or weight-based (0.5 mg/kg every 12 hours) enoxaparin dosing. Enoxaparin was initiated during inpatient hospitalization and continued at discharge for 14 days. Those with contraindication to anticoagulation, plan for therapeutic anticoagulation, or known renal impairment were excluded. The trial was unmasked. The primary outcome was prophylactic (0.2-0.6 international units/mL) peak anti-Xa level 4-6 hours after at least the third enoxaparin dose (at steady state). Secondary outcomes included subprophylactic and supraprophylactic peaks, outpatient peak, and venous thromboembolism (VTE) and wound complications in the first 6 weeks postpartum. Sample size of 121 per group was planned. At interim analysis with 50% enrollment, the trial was stopped early for efficacy. Primary analyses followed intention-to-treat principle with worst-case imputation for missing outcomes. Secondary analyses were complete case.

RESULTS

From June 2020 to November 2021, 74 individuals were randomized to weight-based enoxaparin and 72 to fixed-dose enoxaparin. Those who received weight-based dosing were more likely to achieve prophylactic anti-Xa levels than those who received fixed dosing in primary analysis (49/74 [66%] vs 32/72 [44%], relative risk [RR] 1.49, 95% CI 1.10-2.02) and secondary analysis (49/60 [82%] vs 32/57 [56%], RR 1.45, 95% CI 1.12-1.88). Subprophylactic levels occurred more frequently with fixed dosing; supraprophylactic levels did not differ significantly by dosing. At the outpatient postoperative visit, 52% of participants (15/29) with weight-based dosing compared with 15% (5/33) with fixed dosing achieved prophylactic peak anti-Xa level (RR 3.41, 95% CI 1.42-8.24). There were no VTEs in either group. Wound complications occurred in five individuals (7%) with weight-based enoxaparin dosing compared with one individual (1%) with fixed enoxaparin dosing (RR 4.86, 95% 0.58-40.63).

CONCLUSION

Weight-based dosing was more effective than fixed enoxaparin dosing in achieving prophylactic peak anti-Xa levels after cesarean delivery.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT04305756.

Venous thromboembolism during pregnancy and postpartum period

Venous thromboembolism (VTE) is one of the leading causes of maternal mortality. Rates of VTE during pregnancy and the postpartum period have not decreased over the past two decades and pregnancyassociated VTE continues to pose a significant health challenge. Pregnant and postpartum women are at a higher risk for VTE owing to many factors. There are hormonally mediated and pregnancy-specific alterations of coagulation that favor thrombosis, including increased production of clotting factors. There are physiologic and anatomic mechanisms that also contribute, including a decreased rate of venous blood flow from the lower extemities as pregnancy progresses. Cesarean delivery also introduces VTE risk. In addition, studies have demonstrated that pregnancy-associated complications such as pre-eclampsia or peri-partum infections are associated with increased VTE rates. In this review, we discuss the recent epidemiological studies, pathogenesis, risk factors and clinical presentation as well as therapeutic options for VTE during pregnancy and the postpartum period. We also provide proposed diagnostic algorithms for diagnosis and management of VTE during pregnancy and the postpartum period based on updated evidence. Finally, we highlight knowledge gaps to guide future research.

Prophylaxis and management of venous thromboembolism during pregnancy and postpartum period

Introduction. Venous thromboembolism (VTE) is one of the lead causes for maternal mortality and morbidity during pregnancy in the majority of developed countries. The incidence rate of VTE per pregnancy-year increases during pregnancy and postpartum period about by 4-fold and at least 14-fold, respectively.

Aim: to analyze and summarize current view on risk factors of thrombotic events during gestation and to discuss recent guidelines for the management of venous thromboembolic complications during pregnancy and postpartum, by taking into account a balance between risks and benefits of using anticoagulants.

Materials and Methods. The literature search covering the last 10 years was carried out in the electronic scientific databases RSCI, PubMed/MEDLINE, and Embase. While formulating a search strategy for evidence-based information, the PICO method (P = Patient; I = Intervention; C = Comparison; O = Outcome) and the key terms “venous thromboembolism” and “pregnancy” were used.

Results. Risk factors were found to include a personal history of VTE, verified inherited or acquired thrombophilia, a family history of VTE and general medical conditions, such as immobilization, overweight, varicose veins, some hematological diseases and autoimmune disorders. VTE is considered being potentially preventable upon prophylactic administration of anticoagulants, but no high confidence randomized clinical trials comparing diverse strategies of thromboprophylaxis in pregnant women have been proposed so far. Because heparins do not cross the placenta, weight-adjusted therapeutic-dose low molecular weight heparins (LMWH) represent the anticoagulant treatment of choice for VTE during pregnancy. Once- and twice-daily dosing regimens are acceptable. However, no evidence suggesting benefits for measurement of factor Xa activities and consecutive LMWH dose adjustments to improve clinical outcomes are available. In case of uncomplicated pregnancy-related VTE, no routine administration of vitamin K antagonists, direct thrombin or factor Xa inhibitors, fondaparinux, or danaparoid is recommended. Lactating women may switch from applying LMWH to warfarin. Anticoagulation therapy should be continued for 6 weeks postpartum with total duration lasting at least for 3 months.

Conclusion. VTE is a challenging task in pregnant women expecting to apply a multi-faceted approach for its efficient solution by taking into account updated recommendations and personalized patient-oriented features.

What Do We Know about Thromboprophylaxis and Its Monitoring in Critically Ill Patients?

Venous thromboembolism (VTE), including deep vein thrombosis and pulmonary embolism, is an important complication in patients hospitalized in intensive care units (ICU). Thromboprophylaxis is mainly performed with Low Molecular Weight Heparin (LMWH) and, in some specific patients, with Unfractionated Heparin (UFH). These intensive units are an environment where individual patient variability is extreme and where traditional antithrombotic protocols are frequently ineffective. This was known for a long time, but the hospitalization of many patients with COVID-19 inflammatory storms suddenly highlighted this knowledge. It is therefore reasonable to propose variable antithrombotic prevention protocols based initially on a series of individual criteria (weight, BMI, and thrombotic risks). Secondly, they should be adjusted by the monitoring of anticoagulant activity, preferably by measuring the anti-Xa activity. However, we still face unresolved questions, such as once- or twice-daily LMWH injections, monitoring at the peak and/or trough, and poorly defined therapeutic targets. Equally surprisingly, we observed a lack of standardization of the anti-Xa activity kits.

Venous thromboembolism prophylaxis for women at risk during pregnancy and the early postnatal period

BACKGROUND

Venous thromboembolism (VTE), although rare, is a major cause of maternal mortality and morbidity. Some women are at increased risk of VTE during pregnancy and the early postnatal period (e.g. caesarean section, family history of VTE, or thrombophilia), and so prophylaxis may be considered. As some methods of prophylaxis carry risks of adverse effects, and risk of VTE is often low, benefits of thromboprophylaxis may be outweighed by harms.

OBJECTIVES

To assess the effects of thromboprophylaxis during pregnancy and the early postnatal period on the risk of venous thromboembolic disease and adverse effects in women at increased risk of VTE.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (18 October 2019). In addition, we searched ClinicalTrials.gov and the WHO International Clinical Trials Registry Platform (ICTRP) for unpublished, planned and ongoing trial reports (18 October 2019).

SELECTION CRITERIA

Randomised trials comparing one method of thromboprophylaxis with placebo or no treatment, or two (or more) methods of thromboprophylaxis.

DATA COLLECTION AND ANALYSIS

At least two review authors assessed trial eligibility, extracted data, assessed risk of bias, and judged certainty of evidence for selected critical outcomes (using GRADE). We conducted fixed-effect meta-analysis and reported data (all dichotomous) as summary risk ratios (RRs) with 95% confidence intervals (CIs).

MAIN RESULTS

Twenty-nine trials (involving 3839 women), overall at moderate to high risk of bias were included. Trials were conducted across the antenatal, peripartum and postnatal periods, with most in high-income countries. Interventions included types and regimens of heparin (low molecular weight heparin (LMWH) and unfractionated heparin (UFH)), hydroxyethyl starch (HES), and compression stockings or devices. Data were limited due to a small number of trials in comparisons and/or few or no events reported. All critical outcomes (assessed for comparisons of heparin versus no treatment/placebo, and LMWH versus UFH) were considered to have very low-certainty evidence, downgraded mainly for study limitations and imprecise effect estimates.  Maternal death was not reported in most studies. Antenatal (± postnatal) prophylaxis For the primary outcomes symptomatic thromboembolic events pulmonary embolism (PE) and/or deep vein thrombosis (DVT), and the critical outcome of adverse effects sufficient to stop treatment, the evidence was very uncertain.  Symptomatic thromboembolic events: - heparin versus no treatment/placebo (RR 0.39; 95% CI 0.08 to 1.98; 4 trials, 476 women; very low-certainty evidence); - LMWH versus UFH (RR 0.47; 95% CI 0.09 to 2.49; 4 trials, 404 women; very low-certainty evidence); Symptomatic PE: - heparin versus no treatment/placebo (RR 0.33; 95% CI 0.02 to 7.14; 3 trials, 187 women; very low-certainty evidence); - LMWH versus UFH (no events; 3 trials, 287 women); Symptomatic DVT: - heparin versus no treatment/placebo (RR 0.33; 95% CI 0.04 to 3.10; 4 trials, 227 women; very low-certainty evidence); - LMWH versus UFH (no events; 3 trials, 287 women); Adverse effects sufficient to stop treatment: - heparin versus no treatment/placebo (RR 0.49; 95% CI 0.05 to 5.31; 1 trial, 139 women; very low-certainty evidence); - LMWH versus UFH (RR 0.07; 95% CI 0.01 to 0.54; 2 trials, 226 women; very low-certainty evidence). Peripartum/postnatal prophylaxis Vaginal or caesarean birth When UFH and no treatment were compared, the effects on symptomatic thromboembolic events (RR 0.16; 95% CI 0.02 to 1.36; 1 trial, 210 women; very low-certainty evidence), symptomatic PE (RR 0.16; 95% CI 0.01 to 3.34; 1 trial, 210 women; very low-certainty evidence), and symptomatic DVT  (RR 0.27; 95% CI 0.03 to 2.55; 1 trial, 210 women; very low-certainty evidence) were very uncertain.  Maternal death and adverse effects sufficient to stop treatment were not reported. Caesarean birth Symptomatic thromboembolic events: - heparin versus no treatment/placebo (RR 1.30; 95% CI 0.39 to 4.27; 4 trials, 840 women; very low-certainty evidence); - LMWH versus UFH (RR 0.33; 95% CI 0.01 to 7.99; 3 trials, 217 women; very low-certainty evidence); Symptomatic PE: - heparin versus no treatment/placebo (RR 1.10; 95% CI 0.25 to 4.87; 4 trials, 840 women; very low-certainty evidence); - LMWH versus UFH (no events; 3 trials, 217 women);  Symptomatic DVT: - heparin versus no treatment/placebo (RR 1.30; 95% CI 0.24 to 6.94; 5 trials, 1140 women; very low-certainty evidence); LMWH versus UFH (RR 0.33; 95% CI 0.01 to 7.99; 3 trials, 217 women; very low-certainty evidence); Maternal death: - heparin versus placebo (no events, 1 trial, 300 women); Adverse effects sufficient to stop treatment: - heparin versus placebo (no events;  1 trial, 140 women). Postnatal prophylaxis No events were reported for LMWH versus no treatment/placebo for: symptomatic thromboembolic events, symptomatic PE and symptomatic DVT (all 2 trials, 58 women), or maternal death (1 trial, 24 women). Adverse effects sufficient to stop treatment were not reported. We were unable to conduct subgroup analyses due to lack of data. Sensitivity analysis including the nine studies at low risk of bias did not impact overall findings.

AUTHORS' CONCLUSIONS

The evidence is very uncertain about benefits and harms of VTE thromboprophylaxis in women during pregnancy and the early postnatal period at increased risk of VTE. Further high-quality very large-scale randomised trials are needed to determine effects of currently used treatments in women with different VTE risk factors. As sufficiently large definitive trials are unlikely to be funded, secondary data analyses based on high-quality registry data are important.

Medications for Pregnant Women With Obesity: Special Considerations

Pregnant women with obesity are at increased risk of a multitude of complications of pregnancy and adverse perinatal outcomes. The risk of some of these complications, such as neural tube defects or preeclampsia, may be mitigated by some medications. Other complications, such as diabetes, venous thromboembolism, and infections, require treatment with medications. Given the changes in pharmacokinetics and pharmacodynamics during pregnancy, which is further enhanced by obesity, the optimal medication and its dose is often researched. This chapter further explores the different complications and common medications that women with obesity are likely to require.

Prevention of Postpartum Venous Thromboembolism

Importance

Postpartum venous thromboembolism (VTE) results in significant morbidity and mortality. The practicing obstetrician-gynecologist should have a plan for management and prevention.

Objective

The objective of this review is to familiarize obstetric providers with available evidence regarding postpartum VTE prevention and suggest a clinical practice guideline.

Evidence Acquisition

Published literature was retrieved through a search of PubMed and relevant review articles, original research articles, systematic reviews, and practice guidelines.

Results

Thromboembolic disease is one of the leading causes of maternal death in developed nations. Current evidence does not support universal postpartum VTE prophylaxis. Risk factor stratification is suggested to identify patients at high risk of VTE. Recent guidelines have recommended complex algorithms that are difficult to put into practice and have not been validated in the postpartum state. The American College of Obstetricians and Gynecologists has recommended that each institution develop a protocol to identify and treat women at high risk of postpartum VTE.

Conclusions and Relevance

Obstetric providers should be familiar with available evidence and best practice regarding postpartum VTE prevention. A suggested clinical practice guideline for the prevention of postpartum VTE is provided.

ACOG Practice Bulletin No. 212: Pregnancy and Heart Disease

Maternal heart disease has emerged as a major threat to safe motherhood and women's long-term cardiovascular health. In the United States, disease and dysfunction of the heart and vascular system as "cardiovascular disease" is now the leading cause of death in pregnant women and women in the postpartum period () accounting for 4.23 deaths per 100,000 live births, a rate almost twice that of the United Kingdom (). The most recent data indicate that cardiovascular diseases constitute 26.5% of U.S. pregnancy-related deaths (). Of further concern are the disparities in cardiovascular disease outcomes, with higher rates of morbidity and mortality among nonwhite and lower-income women. Contributing factors include barriers to prepregnancy cardiovascular disease assessment, missed opportunities to identify cardiovascular disease risk factors during prenatal care, gaps in high-risk intrapartum care, and delays in recognition of cardiovascular disease symptoms during the puerperium. The purpose of this document is to 1) describe the prevalence and effect of heart disease among pregnant and postpartum women; 2) provide guidance for early antepartum and postpartum risk factor identification and modification; 3) outline common cardiovascular disorders that cause morbidity and mortality during pregnancy and the puerperium; 4) describe recommendations for care for pregnant and postpartum women with preexisting or new-onset acquired heart disease; and 5) present a comprehensive interpregnancy care plan for women with heart disease.

Evaluation of unmet clinical needs in prophylaxis and treatment of venous thromboembolism in at-risk patient groups: pregnancy, elderly and obese patients

BACKGROUND

Venous thromboembolism (VTE) accounts for an estimated 900,000 cases per year in the US alone and constitutes a considerable burden on healthcare systems across the globe.

OBJECTIVE

To understand why the burden is so high, qualitative and quantitative research was carried out to gain insights from experts, guidelines and published studies on the unmet clinical needs and therapeutic strategies in VTE prevention and treatment in three populations identified as being at increased risk of VTE and in whom VTE prevention and treatment were regarded as suboptimal: pregnant women, the elderly and obese patients.

METHODOLOGY

A gap analysis methodology was created to highlight unmet needs in VTE management and to discover the patient populations considered most at risk. A questionnaire was devised to guide qualitative interviews with 44 thrombosis and haemostasis experts, and a review of the literature on VTE in the specific patient groups from 2015 to 2017 was completed. This was followed by a Think Tank meeting where the results from the research were discussed.

RESULTS

This review highlights the insights gained and examines in detail the unmet needs with regard to VTE risk-assessment tools, biomarkers, patient stratification methods, and anticoagulant and dosing regimens in pregnant women, the elderly and obese patients.

CONCLUSIONS

Specifically, in pregnant women at high risk of VTE, low-molecular-weight heparin (LMWH) is the therapy of choice, but it remains unclear how to use anticoagulants when VTE risk is intermediate. In elderly patients, evaluation of the benefit of VTE prophylaxis against the bleeding risk is particularly important, and a head-to-head comparison of efficacy and safety of LMWH versus direct oral anticoagulants is needed. Finally, in obese patients, lack of guidance on anticoagulant dose adjustment to body weight has emerged as a major obstacle in effective prophylaxis and treatment of VTE.

American Society of Hematology 2018 guidelines for management of venous thromboembolism: venous thromboembolism in the context of pregnancy

BACKGROUND

Venous thromboembolism (VTE) complicates ∼1.2 of every 1000 deliveries. Despite these low absolute risks, pregnancy-associated VTE is a leading cause of maternal morbidity and mortality.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians and others in decisions about the prevention and management of pregnancy-associated VTE.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The McMaster University GRADE Centre supported the guideline development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used to assess evidence and make recommendations.

RESULTS

The panel agreed on 31 recommendations related to the treatment of VTE and superficial vein thrombosis, diagnosis of VTE, and thrombosis prophylaxis.

CONCLUSIONS

There was a strong recommendation for low-molecular-weight heparin (LWMH) over unfractionated heparin for acute VTE. Most recommendations were conditional, including those for either twice-per-day or once-per-day LMWH dosing for the treatment of acute VTE and initial outpatient therapy over hospital admission with low-risk acute VTE, as well as against routine anti-factor Xa (FXa) monitoring to guide dosing with LMWH for VTE treatment. There was a strong recommendation (low certainty in evidence) for antepartum anticoagulant prophylaxis with a history of unprovoked or hormonally associated VTE and a conditional recommendation against antepartum anticoagulant prophylaxis with prior VTE associated with a resolved nonhormonal provoking risk factor.

Venous thromboembolism prophylaxis of the obese postpartum patient: A cross-sectional study

BACKGROUND

Obesity increases risk of venous thromboembolism (VTE) in obstetric patients regardless of delivery mode and for up to six weeks postpartum.

AIM

This study aimed to examine postpartum pharmacological VTE prophylaxis practices for obese women at an Australian tertiary referral hospital.

MATERIALS AND METHODS

Medical records were retrieved for obese obstetric patients who delivered during May 2016-May 2017. Records were examined for demographic data, VTE risk factors, and LMWH (low-molecular-weight heparin) use. Due to lack of specific Australian or local guidelines, practice was evaluated using recommendations from the Royal College of Obstetricians and Gynaecologists (RCOG-UK). Patients with BMI (body mass index) <30, incomplete/unavailable medical records, and those discharged from other health services were excluded.

RESULTS

One hundred and eight postpartum patients (70 caesareans, 38 vaginal deliveries) with a BMI ≥ 30 kg/m² were reviewed. Of these patients, 53 (49.1%) had a BMI ≥ 40 kg/m² . Ninety-eight of 108 (90.7%) patients had ≥2 VTE risk factors including a BMI ≥ 30 kg/m² . One hundred and three of 108 (95.4%) patients were indicated for postpartum VTE prophylaxis with LMWH, and 77 of 103 (74.8%) patients received it. Three of five patients meeting criteria for ≥6 weeks of LMWH thromboprophylaxis had it prescribed. Of the 72 patients whose weight exceeded 90 kg and who also received LMWH, 32 (44.4%) were prescribed a weight-adjusted dose.

CONCLUSION

VTE prophylaxis practices using LMWH in obese postpartum patients, including weight-adjusting doses and extended-course prescribing, appear variable. Limited literature, recommendation discrepancies, and varied awareness of recommendations may be contributing factors. Further education and research regarding this high-risk cohort are warranted.

Pearls in clinical obstetrics: challenges in anticoagulation in pregnancy

Women are at increased risk for venous thromboembolism (VTE) during both pregnancy and in the post-partum period. We have conducted a comprehensive literature review of the use of anticoagulation in pregnancy for pregnant women at increased risk for VTE. Multiple factors, including physiologic and pharmacokinetic changes make the treatment and prevention of VTE complicated in pregnancy. Adequate treatment and prevention of VTE in pregnancy is critically important, yet good quality medical studies continue to be lacking. There is a growing amount of data for the use of low molecular weight heparin (LMWH) in pregnant women and this remains the treatment of choice in most indications. For both prophylactic and therapeutic treatments, when LMWHs are chosen, monitoring of antifactor Xa level, although controversial, is advised. Women with prosthetic valve who become pregnant face challenges in regard of type of anticoagulation, dosing and monitoring during pregnancy. Delivery options and peripartum care should be defined with a multidisciplinary approach and taking patient's preference and autonomy in consideration. More high-quality research on this topic is needed to guide the clinical care of this unique population.

Anti-factor Xa levels in obese patients receiving enoxaparin for treatment and prophylaxis indications

OBJECTIVES

To evaluate the degree of anticoagulation achieved with different enoxaparin dosing regimens used in obese and morbidly obese patients in a hospital setting in Jordan.

METHODS

All obese adult patients who were prescribed enoxaparin for various indications were invited to participate in the study. The anti-factor Xa (anti-Xa) level was checked once after 4-6 hours of the third or fourth dose of enoxaparin (at steady state). Patients were followed daily to evaluate drug efficacy and safety through their hospital course.

RESULTS

Enoxaparin daily dose used for prophylaxis indications ranged from 0.3 to 0.85 mg/kg and from 0.31 to 2.25 mg/kg in case of certain treatment indications. Most participants who received enoxaparin for treatment indications (76.9%) were on capping dosing regimens, which was <1 mg/kg twice daily. On the other hand, most patients (88.5%) who received enoxaparin for prophylaxis indications were on a fixed 40 mg/d dose. Among the 52 patients who completed the study, 19 patients (36.5%) had therapeutic anti-Xa levels. The results showed no statistically significant associations between regimens that were used and achieving therapeutic anti-Xa level (p>0.05). No bleeding events or thrombocytopenia were noticed, and there was one case of recurrent thrombosis.

CONCLUSION

Enoxaparin dosing regimens that were used for obese patients varied based on prescribing physicians. Regardless of the regimen used, the majority of participants had nontherapeutic anti-Xa. Individualized dosing regimens based on anti-Xa levels are warranted for obese patients on enoxaparin.