1. Below the Knee DVT and Pregnancy Related Thrombosis Robert Lampman, MD Morning Report July 2009

2. “…a randomized trial in which no long- term anticoagulant treatment was administered to patients with symptomatic calf-vein thrombosis, which documented a 20% rate of symptomatic extension and/or recurrence of thrombosis within 3 months” CHEST June 2008

3. Provoked and Unprovoked DVTs –Distal DVT 2% risk recurrence with treatment –Proximal DVT / PE 6% risk recurrence Treatment 4-6wks Provoked DVTs –Short duration therapy (4-6wks) give OR 2.9 risk of recurrence compared to 3-6mos. CHEST June 2008

4. “For patients with a first isolated distal DVT that is unprovoked, we suggest that 3 months of anticoagulant therapy is sufficient rather than indefinite therapy (Grade 2B). CHEST June 2008

5. “Isolated calf vein DVT is treated with anticoagulation if it is symptomatic. If not treated with anticoagulation, patients with calf vein DVTs should undergo serial compression ultrasonagraphy to assess for proximal extension.” Washington Manual 31 st Edition. “Thrombotic Disorders”

6. “If anticoagulation is not administered (eg, isolated asymptomatic distal venous thrombosis), serial noninvasive studies of the lower extremity should be performed over the next 10 to 14 days to assess for proximal extension of the thrombus.” UpToDate “Treatment of deep vein thrombosis” Jan 2009

7. Wells Criteria 1.Clinical Signs and Symptoms of DVT? ……………………….Yes +3 2.PE Is #1 Diagnosis, or Equally Likely? ……………………….Yes +3 3.Heart Rate > 100?………………………………………………Yes +1.5 4.Immobilization at least 3 days, or Surgery in the Previous 4 weeks? …………………Yes +1.5 5.Previous, objectively diagnosed PE or DVT? ……………….Yes +1.5 6.Hemoptysis? …………………………………………………….Yes +1 7.Malignancy w/ Treatment within 6 mo, or palliative?………..Yes +1

8. Wells Criteria ScoreTraditional clinical probability assessment High>6.0 Moderate2.0 to 6.0 Low<2.0 Simplified clinical probability assessment PE likely>4.0 PE unlikely <4.0 UpToDate referencing” van Belle, et al. JAMA 2006; 295:172.

9. The ICU Book 3 rd Edition © 2007

10. D-dimer Conditions that can elevate plasma D-dimer levels –Sepsis –Malignancy –Pregnancy –heart failure –renal failure –advanced age “As a result, a majority (up to 80%) of ICU patients have elevated plasma D-dimer levels in the absence of venous thromboembolism”

11. The ICU Book 3 rd Edition © 2007

12. Pregnancy and Thrombosis 18 per 100,000 women during pregnancy 1900 per 100,000 women post-partum Rate 1.72 per 1000 deliveries PEs are most common cause of pregnancy related maternal death in developed countries. Vasc Med. 2008 Aug;13(3):255-66.

13. Pregnancy and Thrombosis Risk higher w/ age >35, multiparous women, pre-existing heart disease, pre- eclampsia, and other thrombophilias. Antiphospholipid antibodies –Lupus Anticoagulant > Anticardiolipin Abs Vasc Med. 2008 Aug;13(3):255-66.

14. Pregnancy and Thrombosis Causes of increased thrombophilia: –Increased fibrinogen –Alterations clotting factor concentrations –Acquired activated protein C resistance Vasc Med. 2008 Aug;13(3):255-66.

15. OCP and Thrombosis Secondary to Elevated Estrogens –Prothrombotic: Elevated levels of prothrombin; Factors VII, VIII, IX, X, and XI; and fibrinogen with decreased levels of protein S and antithrombin. –Antithrombotic proteins are also altered, including elevated levels of protein C, alpha-antitrypsin, and plasminogen with reduced levels of plasminogen activating inhibitor-1. Resistance to activated protein C seems to underlie the major effect of OCPs’ thrombogenic potential. Vasc Med. 2008 Aug;13(3):255-66.