1. Venous Thromboembolism Prophylaxis for Medical Inpatients
Dennis Whang
4/2/12
DSR2 Mini Lecture

2. Objectives
Recognize the morbidity and mortality with venous thromboembolism of inpatients
Determine the risk of VTE for each nonsurgical inpatient admitted
Decide the VTE prophylaxis for each nonsurgical inpatient admitted

3. Background
Most medical inpatients are at risk for venous thromboembolism (VTE):
Deep venous thrombosis (DVT)
Pulmonary embolus (PE)
25% of all VTE cases occur during hospitalization
50-75% of VTE cases occur on medical service
5-10% of inpatient deaths are due to PE
Heparin prophylaxis has NOT shown to decrease risk for inpatient mortality
However it has shown to decrease the incidence of PE
VTE prevention is vital for every inpatient admitted using efficacious and safe modalities
Metaanalysis of 10 trials evaluated medical patients wthout stroke
Heparin prophy with reduced risk of mortality RR 0.94 [0.84,1.04]
Decreased risk for PE with heparin RR 0.69 [0.52,0.90]

4. Deciding VTE Prophylaxis
Must weigh TWO factors before deciding ppx
VTE Risk
Bleeding risk

5. VTE Prophylaxis Guideline
Patient admitted
Determine risk of VTE
Low
Early ambulation
Or High
Moderate
Determine bleeding risk
Anticoagulant prophylaxis
High
Intermittent pneumatic compression
No formal prospective-validated model to determine risk for VTE for hospitalized medical patients
ICU patients are automatically considered high risk for VTE
Risk of VTE
Low risk if all 3:
Younger than 40
Mobile
No thrombotic risk factors
Moderate risk: All other patients
High risk: ICU patients
High Bleeding Risk
Active gastroduodenal bleed
Bleeding within 3 months prior to admission
Platelet count of < 50

6. Thrombotic Risk Factors for VTE
Obesity: BMI > 30
Smoking
Immobility
Malignancy
Previous VTE
Placement of central venous catheter
Inherited or acquired hypercoagulable states
Oral contraceptives/Hormone replacement therapy/tamoxifen
Admission diagnosis of:
Congestive heart failure (NYHA III/VI)
Acute COPD exacerbation
Acute infectious disease or sepsis
Acute myocardial infarction
Stroke with lower limb paralysis
Inflammatory bowel disease
VTE risk is 130 times higher in hospitalized patients than community residents, according to study of patients from 1980 to Elderly hospitalized patients had the highest risk.
ICU patients are at the HIGHEST risk for VTE
Pregnancy, highest incidence in post-partum period, especially after c-sections.
Inherited/Acquired hypercoagulable states include:
Factor V Leiden mutation
Prothrombin gene mutation
Protein S deficiency
Protein C deficiency
Antithrombin (AT) deficiency
Antiphospholipid antibody syndrome
Polycythemia vera
Essential thrombocythemia
Paroxysmal nocturnal hemoglobinuria
Nephrotic syndrome

7. Mechanical VTE Prophylaxis
Intermittent pneumatic compression
Contraindicated in leg ischemia from peripheral vascular disease
Ineffective in prevention of VTE
Graduated compression stockings
Venous foot pumps
Compression prevents venous thrombosis by enhancing blood flow in deep veins of legs to prevent venous stasis. Free of side effects. Should start as soon as patient is admitted, with FEW interruptions.
Stockings and foot pumps found no benefit with VTE prophylaxis in one randomized trial, and caused a 4 fold increase of skin ulcers and necrosis. (CLOTS trial, Lancet. 2009;373(9679):1958). Few data supporting venous foot pumps.

8. Pharmacological VTE Prophylaxis
Low dose unfractionated heparin (UFH)
5,000 units SQ TID
Low molecular weight heparin (LMWH)
Enoxaparin (Lovenox) 40 mg SQ daily
Do NOT use if CrCl < 30 ml/min
No statistical difference between UFH and LMWH for VTE prevention in 9 trials
LMWH are primary cleared by kidneys

9. What VTE prophylaxis would you use?
A 62 yo F is admitted for community acquired pneumonia. No prior history of VTE, bleeding, hepatic, or renal failure. Her platelet count is 200.
Moderate risk of VTE
Low risk of bleeding
VTE ppx: unfractionated heparin or enoxaparin
Moderate risk:
Not young
Thrombotic risk factor: admitted for acute illness of respiratory infection

10. What VTE prophylaxis would you use?
A 35 yo M is admitted for acute gout. He is ambulatory. He has no prior VTE, GI bleed, thrombophilia, or malignancy. BMI 23. His platelet count is 240.
Low risk of VTE
Low risk of bleeding
VTE ppx: early ambulation

11. What VTE prophylaxis would you use?
21 yo F admitted to ICU for DKA from poor insulin compliance. She is ambulatory. She has no prior VTE, GI bleed, thrombophilia, or malignancy. Platelet count is 300.
High risk of VTE
Low bleeding risk
VTE ppx: unfractionated heparin or enoxaparin
ICU admission meets criteria of high risk of VTE

12. What VTE prophylaxis would you use?
A 65 yo F is admitted for treatment of an active malignancy. CrCl is 20 ml/min. She has a history of prior VTE but no history of bleeding, hepatic failure. Her platelet count is 250.
Moderate risk for VTE
Low bleeding risk
VTE ppx: unfractionated heparin
Moderate risk due to active malignancy and prior VTE
Cannot use lovenox due to renal impairment CrCl < 30 ml/min

13. VTE Prophylaxis Guideline
Patient admitted
Determine risk of VTE
Low
Early ambulation
Or High
Moderate
Determine bleeding risk
Anticoagulant prophylaxis
High
Intermittent pneumatic compression
No formal prospective-validated model to determine risk for VTE for hospitalized medical patients
ICU patients are automatically considered high risk for VTE
Risk of VTE
Low risk if all 3:
Younger than 40
Mobile
No thrombotic risk factors
Moderate risk: All other patients
High risk: ICU patients
High Bleeding Risk
Active gastroduodenal bleed
Bleeding within 3 months prior to admission
Platelet count of < 50

14. Summary Be aware of VTE in all hospitalized patients
Assess risk of VTE with every admission
Use pharmacologic prophylaxis with heparin for patients with moderate to high risk of VTE
If pharmacologic prophylaxis is contraindicated due to high risk of bleeding, use intermittent pneumatic compression
Do not use compression stockings

15. References
Guyatt GH, et al. Executive Summary : Antithrombotic Therapy and Prevention of Thrombosis, 9th ed: American College of Chest Physicians Evidence-Based Clinical Practice Guidelines. Chest 2012;141;7S-47S.
Francis, CW. Prophylaxis for Thromboembolism in Hospitalized Medical Patients. N Engl J Med 2007;356:
Pineo GF. Prevention of venous thromboembolic disease in medical patients. UpToDate, Mar 2012.
Qaseem A, et al. Venous Thromboembolism Prophylaxis in Hospitalized Patients: A Clinical Practice Guideline From the American College of Physicians. Ann Intern Med. 2011;155: