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Deep Vein Thrombosis
Aka: Deep Vein Thrombosis, Venous Thromboembolism, DVT, VTE, Thromboembolism
- See Also
- Pulmonary Embolism
- DVT Prevention
- Deep Vein Thrombosis in Pregnancy
- Upper Extremity DVT
- Epidemiology
- Deep Vein Thrombosis (DVT) represents 66% of Venous Thromboembolism (VTE)
- Pulmonary Embolism (PE) represents the remaining 33% of VTE
- Pulmonary Embolism accompanies proximal DVT in 40%
- Deep Vein Thrombosis is identified in 70% of those with Pulmonary Embolism
- Incidence: Venous Thromboembolism
- General population: 0.1% (100 per 100,000 person years)
- Elderly: 1%
- Hospitalized patients: 15%
- Annual mortality in U.S.: estimated at 60,000 to 100,000 per year
- Risk Factors
- See Deep Vein Thrombosis Risk Factors (includes Recurrent Thromboembolism Risks)
- See Thrombophilia
- Signs
- Clinical exam is unreliable for DVT
- Homans' Sign (no predictive value)
- Homans' Sign: Relaxed foot abnormally plantar flexed
- Pseudo-Homans': Pain on passive dorsiflexion of foot
- Other unreliable signs
- Tenderness
- Distal extremity edema
- Palpable cord
- Differential Diagnosis
- See Leg Edema
- Extremity Trauma
- Cellulitis
- Peripheral Arterial Disease
- Baker's Cyst (Pseudo-thrombosis)
- Superficial Thrombophlebitis
- Diagnosis
- Precautions
- See DVT in Pregnancy
- Exercise caution in pregnancy
- Pregnancy is higher risk of pelvic DVT (which is higher risk of PE and more difficult to detect)
- Step 1: Assess DVT Probability
- See Wells Clinical Prediction Rule for DVT
- If moderate to high probability, goto step 3
- Step 2: Low Probability for DVT
- Obtain D-Dimer
- Negative D-Dimer: Excludes DVT in a low probability patient
- However, D-Dimer Test Sensitivity is 95%, and will miss 5% of DVTs
- Positive D-Dimer: Lower Extremity DopplerUltrasound
- Negative Ultrasound
- Excludes DVT
- Positive Ultrasound
- Treat as DVT
- Step 3: Moderate to high Probability for DVT
- Obtain Lower Extremity DopplerUltrasound (Test Sensitivity approaches 95%)
- Negative Compression Ultrasound: Obtain D-Dimer
- Negative D-Dimer
- Excludes DVT
- Positive D-Dimer
- Repeat Compression Ultrasound in one week or venography
- Positive Compression Ultrasound
- Treat as DVT
- References
- Bockenstedt (2003) N Engl J Med 349:1203-4 [PubMed]
- Management: General
- See DVT in Pregnancy
- See Pulmonary Embolism Management
- Anticoagulation protocols are the same for DVT and PE
- Consider Thrombophilia work-up
- See Thrombophilia
- Reserve blood for tests prior to Anticoagulation
- Anticoagulation Protocol
- Anticoagulation in Thromboembolism
- Disposition
- Hospitalization and Heparin for high risk patients
- Consider home management with LMWH (see below)
- Local measures
- Early ambulation
- Replaces prior recommendations to minimize activity for first few days
- Elevate affected limb to reduce swelling
- Apply heat to affected limb
- Graded elastic Compression Stockings (20-30 mmHg)
- Reduce risk of postphlebitic syndrome (postthrombotic syndrome)
- Kolbach (2004) Cochrane Database Syst Rev (1): CD004174 [PubMed]
- Superficial Venous ThrombosisAnticoagulation indications
- See Superficial Venous Thrombosis
- Proximal superficial clot (upper thigh) especially within 5 cm of deep system
- Clot >7 cm long in leg
- Lack of improvement after 1 week
- Hypercoagulable state
- Management: Distal DVT (Calf-vein DVT)
- Option 1: Anticoagulation (standard strategy since 2001)
- Anticoagulation recommended for 6 to 12 weeks
- Initiate with LMWH and then to oral Warfarin (or other Anticoagulant - see above)
- Justification (based on risk of untreated calf DVT complications)
- Risk of propogation to proximal DVT is 5-20% (NNT 16)
- Recurs in 30% of untreated patients
- Post-thrombotic syndrome occurs in 20% if untreated
- Pinede (2001) Circulation 103:2453-60 [PubMed]
- Utter (2016) JAMA Surg 151(9): e161770 +PMID:27437827 [PubMed]
- Option 2: 2015 Chest Guidelines recommend serial Ultrasound instead of Anticoagulation
- Assumes lower risk patient
- Asymptomatic
- No cancer history or other underlying Coagulopathy
- DVT not unprovoked and not recurrent
- Preferred strategy if Anticoagulation contraindicated or increased bleeding risk
- Safe even in symptomatic patients, with similar outcomes to Anticoagulation, but without the 4% bleeding risk
- Righini (2016) Lancet Hematol 3(12): e556-62 +PMID: 27836513 [PubMed]
- Repeat Doppler Ultrasound twice weekly for 2 weeks
- Monitor for extension of distal DVT to proximal DVT
- Kearon (2016) Chest 149(2): 315-52 +PMID:26867832 [PubMed]
- Management: Anticoagulation
- See Anticoagulation in Thromboembolism
- Management: Home Deep Vein Thrombosis Protocol
- Criteria for home management
- No massive Deep Vein Thrombosis
- No entire Leg Swelling, acrocyanosis or ischemia
- No DVT extension into iliofemoral vein or IVC
- No symptomatic Pulmonary Embolism
- Oxygen Saturation >95% on room air
- No significant bleeding risks on Anticoagulants
- Active bleeding or bleeding in last 4 weeks
- Recent surgery or Trauma
- Platelet Count <70, INR >1.4 or PTT >40 sec
- Metastatic disease involving liver or brain
- No significant comorbidities
- No severe liver or Kidney disease
- Impaired cognition or mobility
- Pain requiring parenteral Narcotics
- References
- Douketis (2005) Can Fam Physician 51:217-23 [PubMed]
- Efficacy
- Safe and effective management of proximal DVT
- Spyropoulos (2002) Chest 122:108-14 [PubMed]
- Review Contraindications
- Use only in otherwise low risk patients
- See Low Molecular Weight Heparin for contraindication
- Patient Education
- Demonstrate self-administered Subcutaneous Injections
- Review sterile technique
- Review risks of bleeding and infection
- Emphasize precautions against Trauma
- Consider home health referral
- Anticoagulation
- See Anticoagulation in Thromboembolism
- Management: Intervention Radiology directed Thrombolysis (with benefit)
- Ileofemoral DVT (typically within last 14 days)
- High risk of comorbidity
- Post-thrombotic syndrome: >50%
- Venous Claudication at 5 years in nearly half of patients
- Efficacy data (some studies question longterm benefit)
- Normal vein after Catheter Thrombolysis: 45% (contrast with 0% after Heparin alone)
- Decreases risk of long term Venous Insufficiency, post-phlebitic syndrome, stasis ulcers
- Best outcome if performed early (within 2 weeks)
- Poor efficacy if prior Deep Vein Thrombosis
- References
- (2009) J Thromb Haemost 7:1268-75 [PubMed]
- Other indications
- Massive proximal extremity DVT with severe symptoms or Limb Threatening Ischemia
- Complications
- Pulmonary Embolism
- Post-thrombotic syndrome (postphlebitic syndrome)
- Reduced with below knee graded Compression Stockings
- Prandoni (2004) Ann Intern Med 141:249-56 [PubMed]
- Encourage 30 minute walk per day
- Kahn (2011) CMAJ 183(1):37-44 +PMID:21098066 [PubMed]
- Phlegmasia (Milk Leg)
- Phlegmasia Alba Dolens
- Painful, white leg following ileo-femoral deep vein obstruction
- Phegmasia Cerulea Dolens
- Painful, cyanotic, edematous leg following ileo-femoral deep and superficial vein obstruction
- Venous Gangrene (capillary obstruction) results if not promptly managed
- Associated Conditions
- See Thrombophilia
- Idiopathic DVT associated with undiagnosed malignancy
- Initiate evaluation for underlying malignancy in the first month of unprovoked DVT
- Directed history and physical
- Consider Chest XRay, Colonoscopy, Mammogram, PSA
- Relative Risk of malignancy diagnosis in 2 years: 3.0
- Oudega (2006) Brit J Gen Pract 56:693-6 [PubMed]
- Prevalence of occult malignancy in unprovoked VTE: 3.9%
- Carrier (2015) N Engl J Med 373(8): 697-704 [PubMed]
- Prognosis
- Mortality: 6% within 1 month of DVT diagnosis
- VTE recurs in 33% of patients within 10 years
- Prevention
- See DVT Prevention
- See DVT Prophylaxis
- See DVT Prevention in Travelers
- Resources
- CDC: Venous Thromboembolism
- https://www.cdc.gov/ncbddd/dvt/data.html
- References
- Feied in Marx (2002) Rosen's Emergency Med, p. 1210-33
- AbuRahma (2001) Ann Surg 233(6):752 [PubMed]
- Forster (2001) Chest 119(2):572-9 [PubMed]
- Hull (2000) Arch Intern Med 160:229-36 [PubMed]
- Hyers (2001) Chest 119:176S-93S [PubMed]
- Lensing (1999) Lancet 253:479-85 [PubMed]
- Merli (2001) Ann Intern Med 134:191-202 [PubMed]
- Ramzi (2004) Am Fam Physician 69:2841-8 [PubMed]
- Wells (2001) Thromb Haemost 86(1):499-508 [PubMed]
- Wilbur (2012) Am Fam Physician 86(10):913-9 [PubMed]