1. VTE Prophylaxis South Dakota Perinatal Association Conference
Annie Siewert, MD, MS, FACOG
South Dakota Perinatal Association Conference
9/21/2018

2. VTE and the Obstetrical Patient
Objectives
Describe Incidence of VTE in the United States
Discuss risk stratification and assessment of VTE in obstetrical patients. 
Discuss current recommendations for VTE prophylaxis in antepartum and postpartum patients.  
VTE and the Obstetrical Patient

3. Maternal Mortality is on the Rise
U.S Maternal Mortality Rate
1987: 7.2 deaths per 100,000 births
2011: 17.8 deaths per 100,000 births
One of only 8 countries to have an increase in maternal mortality
CDC: Pregnancy Mortality Surveillance System

4. VTE and Pregnancy: How big is this problem?

5. Causes of Maternal Mortality in the United States
CDC: Pregnancy Mortality Surveillance System

6. VTE and Pregnancy: Epidemiology
Pregnant women are 4-5X higher risk
/1000 pregnant women
1.1 deaths per 100,000 deliveries
WHO Systemic Review of maternal mortality reports VTE cause of 14.9% of deaths in developed countries
One of leading causes of maternal death in U.S
9% of all maternal deaths in the U.S.
ACOG Practice Bulletin #

7. VTE and Pregnancy: Epidemiology
Pregnancy-Associated VTE
75-80% are caused by DVT
20-25% are caused by Pulmonary Embolism
ACOG Practice Bulletin #

8. VTE and Pregnancy: Epidemiology
Risk of VTE increased 72% between
Increasing BMI
Increased c-section rates
AMA
Increased rate of medical co-morbidities
ACOG Practice Bulletin #

9. VTE: Prevention
Alliance for Innovation (AIM) on Maternal Health
National alliance to promote consistent and safe maternity care
Reduce maternal mortality by 1,000 and severe maternal morbidity by 100,000 instances over the course of four years, 2014 – 2018.
Funded through the federal Maternal and Child Health Bureau.

11. VTE and Pregnancy: Recognition

12. Symptoms of VTE in Pregnancy
Pregnancy causes the Perfect Storm for VTE
Hypercoagulable state
Venous Stasis
Decreased venous outflow
Compression of IVC and pelvic veins by uterus
Decreased mobility
ACOG Practice Bulletin

13. Symptoms of VTE in Pregnancy
Two most common symptoms
Pain
Swelling
Circumference difference of 2cm or more
Homan’s sign is poor diagnostic tool
Obstetrical population is unique
More likely in LLE
More likely proximal involving iliac and iliofemoral veins
UpToDate: Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis. RCOG. April 2015

14. Timing of VTE in Pregnancy
50% occur in during pregnancy
50% occur in postpartum period
UpToDate: Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis. RCOG. April 2015

15. Timing of VTE in Pregnancy
Antepartum: %
Equal distribution of VTE over each trimester
Postpartum: %
2-5X higher risk
Highest risk in the first 6 weeks postpartum
Highest overall risk in first week
TEG parameters abnormal at one week
Risk of VTE after C-section similar over weeks 1, 2, and 3
Normalizes 12-13W postpartum
UpToDate: Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis. RCOG. April 2015

16. VTE and Pregnancy: Where do we go from here?

17. Prevention of VTE
United Kingdom and the Royal Collage of Obstetricians and Gynaecologists (RCOG) has developed robust comprehensive strategy for VTE prevention in the obstetric population
Decreased death from VTE by almost half
: 1.94 per 100,000 deliveries
: 0.79 per 100,000 deliveries

18. Prevention of VTE Thromboprophylaxis is underutilized in the U.S
Typically SCDs
Ordered for only 25% of patients undergoing c-section
Estimated that 75% of woman receive no prophylaxis following C-section

19. VTE: Prevention
Lack of Use and Noncompliance with Mechanical Prophylaxis
Systemic review of >2500 patients
25% were noncompliant with mechanical prophylaxis
Observation study demonstrated noncompliance in 21% of patients after C-section
Endorse Survey
Evaluated prophylaxis rates in 17,084 major surgery patients
38% of patients at risk for VTE did not receive prophylaxis

20. Prevention VTE and Pregnancy
Nationwide movement for the prevention of VTE focusing on:
Establishing guidelines
Risk identification
National society recommendations
ACOG
ACCP
Maternal Safety Bundles
National Partnership for Maternal Safety
VTE and Pregnancy

22. VTE and Pregnancy: Prevention
“The single cause of death most amenable to reduction by systemic change in practice.” Clark, SL. Semin. Perinatol 2012; 36 (1):42-47

23. VTE and Pregnancy: Risk Assessment and Stratification

24. VTE and Pregnancy: Risk Factors
Postpartum
Cesarean Delivery
Medical Comorbidities
BMI>25
Preterm Delivery<36W
Obstetric Hemorrhage
Stillbirth
AMA>35yo
HTN
Smoking
Pre-eclampsia or Eclampsia
Postpartum Infection
Antepartum
Multiple gestation
Varicose Veins
Inflammatory Bowel Disease
UTI
Diabetes
Hospitalization>3 Days
BMI>30
AMA>35yo
UpToDate: Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis

25. VTE Risk Factors: What are the odds?
Previous VTE
Thrombophilia
APA Syndrome
SLE
Heart Disease
BMI>40
Cesarean Section
Elective Cesarean Section
Emergency Cesarean Section
Blood Transfusion
Postpartum Infection
IUGR
Antepartum Hemorrhage
Smoking>10 cigs/day
Multiple gestation
Age>35
CHTN
PreE
Odds Ratio
24.8
51.8
15.8
8.7
7.1
4.0**
3.7**
2.3
3.6
7.6**
4.1**
1.6
1.87
0.9
VTE Risk Factors: What are the odds?

26. VTE: Risk Stratification
Goal is to have an effective tool for risk assessment and use it for every patient
Recommendations from National Societies
ACOG
ACCP
RCOG

27. VTE Prevention: Cesarean Delivery
SCD’s preoperatively and postpartum
Pharmacologic prophylaxis based on risk factors
Opt out strategy
All patients undergoing C-section would receive pharmacologic prophylaxis unless there is a contraindication
New York Presbyterian Hospital

28. VTE: Risk Stratification
ACOG
Previously recommended pharmacologic prophylaxis for small group of women
Prior VTE
Thrombophilias
SCDs for all c-section patients
No further recommendations
ACOG Practice Bulletin #

29. “Current evidence is insufficient to recommend universal adoption of pharmacologic prophylaxis for VTE, and thromboprophylaxis should be individualized according to patient risk factors.”
“…Other candidates for anticoagulation during pregnancy include women with a history of thrombosis or those who are at significant risk of VTE during pregnancy or the postpartum period.”

30. Pregnancy

32. The California Maternal Quality Care Collaborative is a multi- stakeholder organization committed to ending preventable morbidity, mortality and racial disparities in California maternity care. CMQCC uses research, quality improvement toolkits, state- wide outreach collaboratives and its innovative Maternal Data Center to improve health outcomes for mothers and infants. 
 CMQCC was founded in 2006 at Stanford University School of Medicine together with the State of California in response to rising maternal mortality and morbidity rates. Since CMQCC’s inception, California has seen maternal mortality decline by 55 percent between 2006 to 2013, while the national maternal mortality rate continued to rise. 

38. VTE Risk Factors Major Risk Factors Odds Ratio Minor Risk Factors
Previous VTE
24.8
BMI>40* 4
Thrombophilia
51.8
Cesarean Section**
3.7
APA Syndrome
15.8
Elective Cesarean Section
2.3
SLE
8.7
Emergency Cesarean Section
3.6
Heart Disease
7.1
Blood Transfusion**
7.6**
Postpartum Infection**
4.1
IUGR
Antepartum hemorrhage
Smoking >10 cigs/day
Multiple Gestation
1.6
Age >35
CHTN
1.87
PreE
0.9
VTE Risk Factors

39. VTE and Pregnancy: Thromboprophylaxis Implementation

40. Avera Obstetric VTE Risk Assessment Tool
Major Risk Factors
Consider anticoagulation if 1 present
Previous VTE
Thrombophilia
Antithrombin Deficiency
Factor V Leiden
Prothrombin Gene Mutation
Anti-phosholipid Antibody Syndrome
Lupus
Heart Disease
Minor Risk Factors
Consider anticoagulation if 2 or more present
Cesarean section
BMI>40
Age >35
Hemorrhage (if stable hrs)
Postpartum Infection
Multiple gestation
Smoking
General anesthesia
IUGR
Preeclampsia
Chronic hypertension
Blood Transfusion (if stable hrs)

41. Prophylactic Anticoagulation Dosing Regimens Unfractionated heparin
Weight
Enoxaparin
<50kg
20mg Daily
50-90kg
40mg Daily
91-130kg
60mg Daily kg
80mg Daily
>170kg
0.6mg/kg/Day
Unfractionated heparin
Any weight
5000 units twice daily

42. Timing of Anticoagulation After Regional Anesthesia

43. Risk of Bleeding with Prophylactic Anticoagulation
Safety of prophylactic anticoagulation in patients undergoing c-section at Duke University
No differences in EBL at delivery
No change in postpartum hematocrit
No difference in blood product administration
Limmer et al. Thrombosis Research 132 (2013) e19-23

44. Contraindications to LMWH Administration
Hemophilia or other known bleeding disorder
Active or threatened antenatal bleeding (consider holding LMWH/UFH 12–24h after cessation of bleeding)
Thrombocytopenia (platelet count <75K)
Recent stroke (hemorrhagic/ischemic)
Severe renal disease (GFR < 30ml/min)
Severe liver disease (prolonged PT)
Uncontrolled hypertension (BP > 200mmHg systolic or >120mmHg diastolic)
Limmer et al. Thrombosis Research 132 (2013) e19-23

45. THANK YOU!!

46. References
Limmer et al. Postpartum wound and bleeding complications in Women who received peripartum anticoagulation. Thrombosis Research 132 (2013) e19-23
Bates SM., Greer IA., Middeldorp S., Veenstra DL., Prabulos AM., Vandvik PO. VTE, thrombophilia, antithrombotic therapy, and pregnancy: Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012; 141(Suppl): e691S–736S 
James AH , Jamison MG , Brancazio LR , Myers ER . Venous thromboembolism during pregnancy and the postpartum period: incidence, risk factors, and mortality. Am J Obstet Gynecol. 2006;194(5):
Jacobsen AF, Skjeldestad FE , Sandset PM . Ante- and post- natal risk factors of venous thrombosis: a hospital-based case-control study. J Thromb Haemost. 2008;6(6):
ACOG Practice Bulletin #196. Thromboembolism in Pregnancy. July 2018.
CDC: Pregnancy Mortality Surveillance System.
UpToDate: Deep vein thrombosis in pregnancy: Epidemiology, pathogenesis, and diagnosis. April 14, 2016.
Council on Patient Safety in Women’s Health Care. Safety Action Series: Maternal Venous Thromboembolism Prevention Patient Safety Bundle. December 2015
ACOG District II. Safe Motherhood Initiative: Maternal Safety Bundle for Venous Thromboembolism. November 2015
RCOG. Reducing the Risk of Venous Thromboembolism during Pregnancy and the Puerperium. Green-top Guideline No. 37a; April 2015