Risk scores, prevention, and treatment of maternal venous thromboembolism

Variation among venous thromboembolism risk assessment tools for postcesarean patients: a retrospective cohort study

Venous thromboembolism (VTE) risk in pregnant women is four to five-fold higher than in nonpregnant women, and the risk of VTE is an additional four-fold higher after Cesarean section compared to normal vaginal delivery. Recommendations regarding anticoagulant prophylaxis are inconsistent across international guidelines, and VTE remains one of the leading causes of maternal morbidity and mortality. This study aimed to compare the need for postcesarean anticoagulation for VTE prophylaxis based on three major guidelines and our own institutional protocol. It was a retrospective cohort study that reviewed the medical records of patients who underwent a cesarean section at a tertiary-level care hospital in the United Arab Emirates (UAE). The need for anticoagulation was assessed using clinical tools from the American College of Obstetricians and Gynecologists (ACOG), Royal College Obstetricians and Gynecologists (RCOG), American College of Chest Physicians (ACCP), and the study site hospital protocol. A total of 1134 postcesarean women, aged 18-55 years, were included in the study. Most patients (87%) were at moderate risk for VTE. According to the study site hospital tool, 90.7% qualified for anticoagulant prophylaxis, while the ACOG, RCOG, and ACCP tools indicated that 0.5, 90.9, and 36.7% qualified, respectively. Enoxaparin was the primary anticoagulant used in 95% of cases. Only one patient developed VTE during the follow-up period. Anticoagulation needs assessment tools vary extensively in their estimations, highlighting the need for a uniform tool across multiple societies to establish a consistent standard of care and guide the development of evidence-based, site-specific protocols.

Incidence of maternal venous thromboembolism in China: A systematic review and meta-analysis

BACKGROUND

Venous thromboembolism (VTE) is one of the primary causes of maternal death. Although many studies have reported maternal VTE, no study has estimated the incidence of it in China.

OBJECTIVES

The aim of this work was to estimate the incidence of maternal VTE in China and to compare the risk factors for it.

SEARCH STRATEGY

The authors searched eight platforms and databases including PubMed, Embase, and Cochrane Library from inception to April 2022, with the search terms "venous thromboembolism" AND "puerperium (pregnancy)" AND "incidence" AND "China."

SELECTION CRITERIA

Studies provide data to calculate the incidence of maternal VTE among Chinese patients.

DATA COLLECTION AND ANALYSIS

The authors made a standardized table to collect data and calculated the incidence and 95% confidence intervals (CIs), founding source of heterogeneity by subgroup analysis and meta-regression and judging publication bias by funnel plot and Egger test.

MAIN RESULTS

The included 53 papers with a total sample size of 3 813 871 patients had 2539 cases of VTE, and the incidence of maternal VTE in China was 0.13% (95% CI, 0.11-0.16; P < 0.001).

CONCLUSIONS

The trend in the incidence of maternal VTE in China is stable. Cesarean section and advanced age are associated with a higher incidence of VTE.

Patient-reported barriers and facilitators for intermittent pneumatic compression device use on the antepartum unit

OBJECTIVE

To examine patient barriers to intermittent pneumatic compression (IPC) device compliance during antepartum hospital admissions.

METHODS

This was a prospective survey study of a diverse group of pregnant patients who were admitted to the antepartum floor in a quaternary care hospital from June 2019 through March 2021. Patients receiving pharmacotherapy for venous thromboembolism prophylactic or therapeutic indications were excluded. The primary outcome was patient reported barriers to use of IPC during antepartum hospital admission. Responses were summarized using descriptive statistics.

RESULTS

A total of 40 patients were surveyed. All participants correctly identified the purpose of IPC. When asked regarding IPC importance, 7.5% reported not important, 40% reported somewhat important but not a priority, 5% important only on the first day they were given, and 47.5% reported important whenever the patient was in bed. The most bothersome characteristics of IPC use identified by the respondents on a Likert scale from 1 to 5 were sweating, made the legs too hot, restricted movement, and inconvenience and time spent putting on and taking off the IPC. Making the device wireless/cordless (77.5%), using a lighter weight or cooler material for the cuffs (55%), and better availability of nurses to assist with putting on, taking off, and troubleshooting the IPC (17.5%) were identified by patients as ways to increase compliance with IPC.

CONCLUSIONS

This survey identified several modifiable barriers to the use of IPC on the antepartum floor.

Influences of Antithrombotic Elastic Socks Combined with Air Pressure in Reducing Lower Extremity Deep Venous Thrombosis for Patients Undergoing Cardiothoracic Surgery

This study was designed to investigate the application and therapeutic effect of antithrombotic elastic socks combined with air pressure in the prevention of lower extremity deep venous thrombosis in patients undergoing cardiothoracic surgery. Sixty patients in cardiothoracic surgery of our hospital from January 2019 to December 2020 were randomly divided into a study group and control group. The control group was treated with routine treatment intervention. Based on routine treatment intervention, the study group was treated with antithrombotic elastic socks combined with pneumatic treatment intervention. The activated partial thromboplastin time (APTT), thrombin time (TT), femoral venous blood flow velocity of both lower limbs, and the incidence of lower extremity deep venous thrombosis (LEDVT), postoperative lower extremity swelling, inflammatory factors, and satisfaction were measured. After intervention, APTT (31.74 ± 1.15 s) and TT (14.58 ± 0.24 s) in the study group were higher than those in the control group APTT (25.13 ± 1.14 s) and TT (12.14 ± 0.23 s) (P < 0.05). The left lower limb femoral vein blood flow velocity and the right lower limb femoral vein blood flow velocity in the study group were better than those in the control group (P < 0.05). The incidence of postoperative lower limb swelling and deep vein in the study group was lower than that in the control group (P < 0.05). Serum tumor necrosis factor alpha and interleukin-6 concentrations in the study group were lower than those in the control group (P < 0.05). The satisfaction rate of patients in the study group (93.33%) was significantly higher than that in the control group (70.00%) (P < 0.05). In conclusion, after cardiothoracic surgery, antithrombotic elastic socks combined with air pressure can significantly reduce the incidence of LEDVT by improving patients' coagulation function, reducing inflammatory reaction. It is worthy of popularization and application in relevant surgery.

Hospital Variation and Associated Organizational Factors of Pregnancy-Related Venous Thromboembolism in China

Objective

Identifying organizational factors affecting venous thromboembolism (VTE) incidence and variations between hospitals.

Methods

From a 2019 survey of VTE and live births in 113 hospitals, organizational factors: (hospital type, characteristics, live birth number), resource availability: (D-dimer, B-scan ultrasonography of lower extremity veins, computed tomographic pulmonary angiography [CTPA], and competency: [risk assessment, use of anticoagulants and patient education], data were collected and the associations, weighted by live birth number, analyzed.

Results

Of 113 hospitals in China, 770,828 live births and 526 cases of VTE (68.2 per 100,000 live births) were reported. Nine hospitals lacked B-scan ultrasonography of lower extremity veins and 22 lacked CTPA. Prevalence rates of VTE rates were higher in general hospitals (Odds ratio [OR] = 4.251, 95% CI: 3.373-5.357), hospitals with live births < 10,000 (OR = 1.650-2.193), and hospitals without B-scan ultrasonography (OR = 1.661, 95% CI: 1.096-2.518). Hospitals implementing patient education, had a lower risk of VTE (OR = 0.296-0.374), and VTE rate decreased with the annual increase in live births.

Conclusions

Improved hospital resource availability and competency, especially patient education, is vital for reducing VTE-related maternal mortality and morbidity risk.

Predictive value of D-dimer and analysis of risk factors in pregnant women with suspected pulmonary embolism after cesarean section

Background

Acute pulmonary embolism (PE) is one of the leading causes of maternal mortality, and cesarean section is an established independent risk factor for PE. The diagnostic utility of D-dimer for PE in non-pregnant women has been well-established, but its role in women with suspected PE after cesarean section is unclear. Furthermore, the optimal threshold level in this patient population is unknown. Traditional D-dimer levels have low diagnostic specificity, resulting in many pregnant women being exposed to potentially harmful radiation despite negative diagnostic imaging results. This research aimed to optimize the clinical threshold for D-dimer to improve specificity while ensuring high sensitivity and to identify risk factors for PE after cesarean section.

Methods

This retrospective study of 289 women who underwent diagnostic imaging (ventilation/perfusion [V/Q] or computed tomographic pulmonary angiography [CTPA]) for suspected acute PE after cesarean delivery from 2010 to 2021 was conducted. Clinical data and laboratory indicators within 24 h postpartum including D-dimer levels were collected for analyses.

Results

The final analysis included 125 patients, among whom 33 were diagnosed with acute PE (incidence of 11.42%, 95% confidence interval 7.7–15.1). The receiver operating characteristic curve analysis suggested that a D-dimer cut-off value of 800 ng/mL had specificity of 25.26% and sensitivity of 100% for detecting PE. The cut-off value was adjusted to 1000 ng/mL with a specificity of 34.74% and a sensitivity of 96.67%. Using a D-dimer cut-off value of 800 ng/mL (instead of the conventional value of 500 ng/mL) increased the number of patients excluded from suspected PE from 9.6 to 18.4% without additional false-negative results. Of note, a history of known thrombophilia was significantly more common in patients with PE than in those without (P < 0.05). No other independent risk factors were noted in our study.

Conclusions

The D-dimer cut-off value of 800 ng/mL ensures high sensitivity and increases specificity compared to the conventional threshold of 500 ng/mL. Utilizing this higher threshold can reduce the number of unnecessary CT and subsequently unnecessary radiation exposure, in women after cesarean delivery. Prospective studies should also be conducted to verify these results.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12890-021-01757-3.

Imaging modalities for confirming pulmonary embolism during pregnancy: results from a multicenter international study

OBJECTIVES

We explored the variations in use of imaging modalities for confirming pulmonary embolism (PE) according to the trimester of pregnancy.

METHODS

We included all pregnant patients with confirmed acute PE from RIETE, a prospective registry of patients with PE (03/2001-02/2020). Imaging modalities included computed tomography pulmonary angiography (CTPA), ventilation-perfusion (V/Q) scan, or presence of signs of acute PE along with imaging-confirmed proximal deep vein thrombosis (pDVT) without pulmonary vascular imaging. We compared the imaging modalities to postpartum patients with PE, and other non-pregnant women with PE.

RESULTS

There were 157 pregnant patients (age: 32.7 ± 0.5), 228 postpartum patients (age: 33.9 ± 0.5), and 23,937 non-pregnant non-postpartum women (age: 69.5 ± 0.1). CTPA was the most common modality for confirming PE, from 55.7% in first trimester to 58.3% in second trimester, and 70.0% in third trimester. From first trimester to third trimester, V/Q scanning was used in 21.3%, 16.7%, and 18.3% of cases, respectively. Confirmed pDVT along with the presence of signs/symptoms of PE was the confirmatory modality for PE in 21.3% of patients in first trimester, 19.4% in second trimester, and 6.7% in third trimester. The proportion of postpartum patients confirmed with CTPA (85.5%) was comparable to that of non-pregnant non-postpartum women (83.2%). From the first trimester of pregnancy to postpartum period, there was a linear increase in the proportion of patients with PE diagnosed with CTPA (p = 0.039).

CONCLUSION

CTPA was the primary modality for confirming PE in all trimesters of pregnancy, although its proportional use was higher in later stages of pregnancy.

KEY POINTS

• Computed tomography pulmonary angiography (CTPA) was the primary modality of diagnosis in all trimesters of pregnancy among patients with confirmed pulmonary embolism, even in the first trimester. • From the first trimester of pregnancy to postpartum period, there was a linear increase in the proportion of patients with pulmonary embolism who were diagnosed based on CTPA. • In the postpartum period, use of CTPA as the modality to confirm pulmonary embolism was comparable to non-pregnant patients.