2. Deep vein thrombosis
A form of thrombophlebitis
Incidence- ~1 per 1000 persons per year
Commonly affects leg veins (L>R)-
popliteal, femoral, pelvic
Virchow’s triad-
Decreased blood flow- stasis
Damage to vessel wall
Hypercoagulability
Complication-
Pulmonary embolism
Post-phlebitic syndrome
3. DVT- risk factors
Recent surgery
Hospitalization
Advanced age
Obesity
Immobilization
Thrombophilia- AT-
III/protein C or S
deficiency
Pregnancy
Estrogen containing
OCP
Tobacco use
Prolonged economy
class air travel
Cancer
Infection
4. DVT-clinical presentation
Underlying risk factors
Symptoms
Pain, swelling, redness of leg
Superficial vein dilatation
Signs
Edema, tender veins
Homan’s sign- calf pain on dorsiflexion of foot
Acute DVT may cause impaired circulation
cold extremity, absent pulse, even gangrene
7. Anticoagulation
Low molecular weight heparin (LMWH)
Fondaparinux
Unfractionated heparin- requires
hospitalization & monitoring (aPTT)
Dose- 80 U/kg bolus18 U/kg/hr infusionmonitor aPTT
Long-term Warfarin- at least 3 months
Dose- 5 mg OD x 3 daysmonitor PT
Life-long for life-threatening/recurrent DVT
Monitor PT/INR- 2-3 times normal
8. Other Rx options
Thrombolysis for extensive proximal
clot, increases risk of bleeding
Intermittent pneumatic compression-
(IPC) if heparin CI or post-op.
IVC filter- reduces PE, used in patients
with ICH, potentially prothrombotic
9. DVT- prevention
LMWH/UFH in hospitalised patients with risk
factors for DVT
LMWH post-op.
IPC after knee/hip surgery
Elastic compression stockings during long-
haul flights
Heparin/LMWH/Warfarin in at risk pregnancy
Early mobilization
11. Pulmonary embolism
Commonly embolism from DVT
Risk more with proximal DVT
Risk factors- as for DVT
Clot obstructs pulmonary arterial circulation &
strains right ventricle
12. PE- diagnosis
Risk factors ± DVT
Symptoms-
Mostly silent
~15% of sudden deaths attributable to PE
May cause sudden SOB, pleuritic chest pain,
hemoptysis
Signs
Tachypnea, cyanosis, pleural rub, low-grade fever
RV strain- loud P2, LPSH, raised JVP
13. PE- diagnosis
Investigations-
CBC, PT/aPTT, LFT, RFT- for R/F
CxR- mainly to rule out other pathology
ECG- tachycardia, RV strain, R/O MI
ECHO- RV dysfunction, R/O MI
D-dimer ± US- for DVT
CT pulmonary angiography- for PE Dx
V-Q scan- contrast allergy/CI
14. PE- treatment
Anticoagulation
LMWH/Fondaparinux/Heparin
Warfarin x minimum 3 months, lifelong if recurrent
Thrombolysis
PE with hemodynamic instability
PE with RV dysfunction on ECHO
Surgical thrombectomy
15. H.I.T
Heparin induced thrombocytopenia
An immune reaction to Heparin/LMWH
Paradoxical increase in arterial/venous
thrombosis, with thrombocytopenia
Can occur upto 100 days after exposure
Rx-
Stop Heparin/LMWH
Anticoagulation with direct thrombin inhibitors (monitor aPTT)-
lepirudin, argatroban, bivaluridin- until platelet count
stabilizes
Long-term Warfarin