Application of the RCOG Risk Assessment Model for Evaluating Postpartum Venous Thromboembolism in Chinese Women: A Case-Control Study

Is early bilateral compression ultrasonography and D-dimer monitoring appropriately for prophylaxis and diagnosis of deep venous thrombosis after cesarean section women: a single-center observation study of Chinese Han population

BACKGROUND

Venous thromboembolism (VTE) is most prevalent among parturients following a cesarean section (CS). The objective of this study was to assess the practical utility of bilateral compression ultrasonography (CUS) of the lower limbs, coupled with D-dimer monitoring, in the early diagnosis of VTE within the Han Chinese population.

METHODS

Our prospective observational study included 742 women who underwent CUS and D-dimer testing on the first day post-CS. Subsequently, telephone or outpatient follow-ups were conducted until 42 days postpartum. States of hypercoagulation and thrombosis, as indicated by CUS, were classified as CUS abnormal. A D-dimer level ≥ 3 mg/l was considered the D-dimer warning value. Early ambulation and mechanical prophylaxis were universally recommended for all parturients post-CS. A sequential diagnostic strategy, based on the 2015 RCOG VTE risk-assessment tool, was employed. Therapeutic doses of low-molecular-weight heparin (LMWH) were administered for the treatment of thromboembolic disease. Prophylactic doses of LMWH were given for VTE prophylaxis in parturients with hypercoagulative status accompanied by D-dimer levels ≥ 3 mg/l. All high-risk women (RCOG score ≥ 4 points) were additionally treated with preventive LMWH. Statistical analyses were conducted using the R statistical software, with a two-sided P value < 0.05 considered statistically significant.

RESULTS

Fifteen cases of VTE and 727 instances without VTE were observed. The overall VTE rate post-CS was 2.02% (15/742), with 66.7% (10/15) being asymptomatic. Eleven patients received a VTE diagnosis on the first postpartum day. Among the 41 parturients exhibiting hypercoagulation ultrasound findings and D-dimer levels ≥ 3 mg/l, despite receiving pharmacological VTE prophylaxis with LMWH, 4.88% (2/41) in the high-risk group were eventually diagnosed with VTE. A total of 30.86% (229/742) exhibited normal ultrasound findings and D-dimer levels < 3 mg/l on the first day post-CS, with no VTE occurrences in the postpartum follow-up. According to RCOG's recommendation, 78.03% (579/742) of cesarean delivery women should receive prophylactic anticoagulation, while only 20.62% (153/742) met our criterion for prophylactic anticoagulation.

CONCLUSION

The strategy of timely routine bilateral CUS and D-dimer monitoring is conducive to the early diagnosis and treatment of VTE, significantly reducing the use of LMWH in the Chinese Han population.

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.

Use of the RCOG risk assessment model and biomarkers to evaluate the risk of postpartum venous thromboembolism

BACKGROUND

Venous thromboembolism (VTE) is a leading cause of morbidity and mortality during pregnancy and the puerperium. The vast majority of VTE occurs after childbirth. China has not yet established standard risk assessment model for postpartum venous thromboembolism (VTE), the Royal College of Obstetricians and Gynecologists (RCOG) risk assessment model (RAM) is commonly used in clinic at present. Herein, we aimed to evaluate the validity of the RCOG RAM in the Chinese population and try to formulate a local risk assessment model by combining with other biomarkers for VTE prophylaxis.

METHODS

The retrospective study was conducted from January 2019 to December 2021at Shanghai First Maternity and Infant Hospital which has approximately 30,000 births annually, and the incidence of VTE, differences between RCOG-recommended risk factors, and other biological indicators from medical records were evaluated.

RESULTS

The study included VTE (n = 146) and non-VTE(n = 413) women who examined by imaging for suspicion of postpartum VTE. There was no statistical difference in the incidence rate of postpartum VTE between the low-score group (23.8%) and the high-score group (28%) after stratification by RCOG RAM. However, we found that cesarean section (in the low-score group), white blood cell (WBC) ≥ 8.64*10^9/L (in the high-score group), low-density lipoprotein(LDL) ≥ 2.70 mmol/L, and D-dimer ≥ 3.04 mg/L (in both groups) were highly associated with postpartum VTE. Subsequently, the validity of the RCOG RAM combined with biomarkers as a model for the risk assessment of VTE was estimated and the results showed that this model has good accuracy, sensitivity, and specificity.

CONCLUSIONS

Our study indicated that the RCOG RAM was not the best strategy for predicting postpartum VTE. Combined with some biomarkers (including the value of LDL and D-Dimer, and WBC count), the RCOG RAM is more efficient when identifying high-risk groups of postpartum VTE in the Chinese population.

TRIAL REGISTRATION

This purely observational study does not require registration based on ICMJE guidelines.

Development of a risk assessment scale for perinatal venous thromboembolism in Chinese women using a Delphi-AHP approach

Background

The treatment and prevention of perinatal venous thromboembolism (VTE) are challenging because of the potential for both fetal and maternal complications.

Methods

This study developed a rapid assessment scale for VTE and evaluate its validity based on Delphi-AHP (Analytic Hierarchy Process) method in China. The research was conducted by literature retrieval and two rounds of Delphi expert consultation. The item pools of the scale were developed and a questionnaire was designed according to literature retrieval published between 2010 and 2020. A survey was conducted among experts from 25 level A hospitals in China, and data of experts’ opinions were collected and analyzed by the Delphi method.

Results

A perinatal VTE risk assessment scale was formed, including 5 first-level items, 20 s-level items and 40 third-level items. The response rates in the two rounds of expert consultation were 97.4% and 98.0%, and the authoritative coefficients were 0.89 and 0.92. The coefficients of variation ranged from 0.04 to 0.28.

Conclusions

The scale is significantly valid and reliable with a high authority and coordination degree, and it can be used to assess the risk of perinatal VTE and initiate appropriate thrombophylactic interventions in China.