Deep Venous Thrombosis Peri-Operatively

Anticoagulation Guidelines

Original: June 1996

Revised: March 2001

Guidelines for Prophylaxis

Deep Venous Thrombosis Peri-Operatively

Risk Assessment (Value Noted in Brackets):

o  Major orthopedic surgery of lower limbs:

¨  total knee arthroplasty [ 5 ].

¨  hip fracture [ 5 ].

¨  total hip arthroplasty [ 4 ].

o  Extensive abdominal or pelvic surgery for malignancy [ 4 ].

o  Multiple trauma [ 4 ].

o  Acute spinal cord injury with paralysis [ 4 ].

o  History of DVT/PE [ 3 ].

o  Advanced age:

¨  age over 70 years [ 3 ].

¨  age 61 to 70 years [ 2 ].

¨  age 41 to 60 years [ 1 ].

o  Stroke [ 1 ].

o  CHF [ 1 ].

o  MI [ 1 ].

o  Varicose Veins [ 1 ].

o  Obesity (greater than 20% of IBW) [ 1 ].

o  Congenital and acquired aberrations in hemostatic

mechanisms [ 1 ].

o  General surgery lasting more than 30 minutes [ 1 ].

o  History of pelvic or long bone fracture [ 1 ].

o  Leg edema, ulcers, stasis [ 1 ].

o  Pregnancy or postpartum <1 month [ 1 ].

o  Inflammatory bowel disease [ 1 ].

o  Severe infection [ 1 ].

o  High dose estrogen use [ 1 ].

o  Other

o  Total Risk

References: Available on Request

Recommendations:

Low Risk [ 1 ]:

1.  Early ambulation.

Moderate Risk [ 2 to 3 ]:

1.  Low Dose Unfractionated Heparin at 5000 IU s.c. bid

OR

2.  Intermittent pneumatic compression

OR

3.  Low Molecular Weight Heparin – Tinzaparin (Innohep) 3500 IU s.c. qd until patient is mobilized. Start 6 hours post-op.

High Risk [ 4 or more ]:

1.  Low Molecular Weight Heparin -- Tinzaparin (Innohep) 4500 IU s.c. qd until patient is mobilized. Start 12 hours post-op.

If patient is less than 55kg use 3500 iu. If patient is greater than 70kg consider dosing at 75iu/kg

2.  Low intensity oral anticoagulation -- INR 2 - 3.

OR

3.  Intermittent pneumatic compression plus Low Molecular Weight Heparin or Low Dose Unfractionated Heparin.

Guidelines for Treatment of Venous Thrombosis/Pulmonary Embolism:

Venous Thrombosis:

1.  Intravenous Unfractionated Heparin as per Weight Adjusted PE/DVT Heparin Protocol.

OR

2.  LMWH: Tinzaparin (Innohep) 175 iu/kg body weight s.c. q24h.or

Enoxaparin (Lovenox) 1mg/kg (max.100mg) s.c. q12h or

1.5mg/kg s.c. qd (max.180mg).

Pulmonary Embolism:

1.  Intravenous unfractionated Heparin as per PE/DVT Heparin Protocol or

2.  LMWH: Tinzaparin 175iu/kg body weight sc q24H

Warfarin (Coumadin) should be started within 24 hours after initiation of Heparin or Low Molecular Weight Heparin and the dose adjusted in the usual manner. Heparin or Low Molecular Weight Heparin should be continued for a minimum of five days. INR should be in the therapeutic range (2 to 3) for two consecutive days prior to discontinuing heparin or Low Molecular Weight Heparin.

Guidelines for Unstable Coronary Syndromes, Non-ST Elevation:

1.  Intravenous Unfractionated Heparin as per Weight Adjusted Cardiac Heparin Protocol.

OR

2.  Low Molecular Weight Heparin – Enoxaparin 1mg/kg body weight s.c. q12h not to exceed 100mg bid.

Reversal of Low Molecular Weight Heparin: Protamine IV – 1mg will neutralize 115iu of Unfractionated Heparin (porcine) or 100iu Tinzaparin or 1mg Enoxaparin. A second dose of 0.5mg Protamine per 100iu Tinzaparin or 1mg Enoxaparin may be required three to four hours after the first dose. Maximum single dose of protamine 50mg.

Unfractionated Heparin/LMWH Monitoring: CBC and Creatinine at baseline and twice weekly.