II. Indications
- Venous Thromboembolism Treatment
- Deep Vein Thrombosis Prophylaxis
III. Contraindications (Indications for standard Heparin)
- Previous Deep Vein Thrombosis history
- Ipsilateral DVT
- Two or more DVTs
- Any Venous Thromboembolism
- High risk lesion (e.g. Iliofemoral DVT)
- Pregnancy
- Renal Insufficiency (Creatinine Clearance <30 due to risk of dose stacking and bleeding risk)
- Morbidly obese patients (consider Unfractionated Heparin where BMI>40-45 kg/m2)
- Hepatic Insufficiency
- Active bleeding
- Surgery in prior 5-7 days (However see below)
- Hypercoagulable state
- Inability to undergo outpatient treatment
- Noncompliance
- Thrombocytopenia
- Coagulopathy
- Active Peptic Ulcer Disease
IV. Mechanism
- See Intrinsic Clotting Pathway
- LMWH, like Heparin, binds to, and potentiates Antithrombin III (AT III)
- Antithrombin III binds to an inhibits Factor Xa
- Results in decreased Thrombin (and ultimately Fibrin) formation
- In contrast to Heparin
V. Efficacy: Unstable Angina and Myocardial Infarction
- Significantly better outcomes than standard Heparin
- Randomized trial (n=3171)
- Lower endpoint (death, Myocardial Infarction, Angina)
- 14 days (16.6 vs 19.8%)
- 20 days (19.8 vs 23.3%)
- Fewer revascularization procedures (27 vs 32.2%)
- Reference
VI. Efficacy
- Comparable efficacy to Heparin in DVT
- References
VII. Advantages: LMWH over Unfractionated Heparin
- Rarely causes Heparin Induced Thrombocytopenia
- Does not cause paradoxical thrombotic events
- Results in fewer bleeding complications
- References
VIII. Dosing
-
General
- Prophylaxis: Consider increasing the dose by 25% when BMI >40 kg/m2
- Treatment: Dose should be based on total body weight (even in obese patients)
- Exception: Fragmin has a maximum dose (unlike other LMWH agents)
- See specific preparation (e.g. Enoxaparin or Lovenox) for adjustments for Renal Function and Obesity
-
Deep Vein Thrombosis Treatment
- Enoxaparin (Lovenox)
- Twice daily dosing: 1 mg/kg SQ twice daily
- Avoid once daily dosing of 1.5 mg/kg SQ daily (less effective, esp. in obese patients, and not for home)
- Available in 30 mg vials
- Tinzaparin (Innohep)
- Dose: 175 anti-Xa IU per kg daily
- Dose (ml): (weight in kg) x 0.00875 ml/kg daily
- Enoxaparin (Lovenox)
-
Deep Vein Thrombosis Prophylaxis
- Ardeparin (Normiflo)
- Initial: 50 U/kg SQ following surgery
- Later: bid for 14 days or until ambulatory
- Dalteparin (Fragmin)
- Low risk
- Initial: 2500 IU SQ 1-2 hours before surgery
- Later: 2500 IU qd for 5-10 days
- High risk
- Initial: 5000 IU SQ the evening before surgery
- Later: 5000 IU qd for 5-10 days
- Low risk
- Danaparoid (Orgaran)
- Initial: 750 U SQ 1-4 hours before surgery
- Later: then 750 U SQ q12h for 7-10 days
- Enoxaparin (Lovenox)
- Initial: 30 mg SQ q12h OR 40 mg daily for 7-10 days
- Increase to 40 mg twice daily for obese patients
- Tinzaparin (Innohep)
- Innohep 3500 IU SQ daily
- Ardeparin (Normiflo)
IX. Precautions
- Severe Renal Insufficiency
- Unpredictable dose response to LMWH
- CrCl <30 ml/min: See specific preparation regarding dosing (e.g. Enoxaparin or Lovenox)
- CrCl <15 ml/min: Use Unfractionated Heparin
-
Obesity (BMI>40)
- Dosing frequency may need adjustment
- Lovenox has been studied at 1 mg/kg up to 190 kg
- For weights above this, follow anti-Xa levels
- Reversal
Images: Related links to external sites (from Bing)
Related Studies
Definition (NCI) | Substances comprised of fragmented heparin molecules derived from unfractionated heparin that bind to antithrombin III with a molecular weight ranging from 1000 to 10,000 daltons, which causes changes in property from unfractionated heparin, including decreased protein binding, enhanced bioavailability, decreased platelet interaction, and decreased binding to thrombin. |
Definition (MSH) | Heparin fractions with a molecular weight usually between 4000 and 6000 kD. These low-molecular-weight fractions are effective antithrombotic agents. Their administration reduces the risk of hemorrhage, they have a longer half-life, and their platelet interactions are reduced in comparison to unfractionated heparin. They also provide an effective prophylaxis against postoperative major pulmonary embolism. |
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | D006495 |
SnomedCT | 373294004, 87233003 |
LNC | LP16001-7, LP172751-2, MTHU014939 |
English | Heparin, Low Molecular Weight, Low Molecular Weight Heparin, LMWH, Low-Molecular-Weight Heparin, Low Mol Wt Heparin (Obsolete), LOW MOL WEIGHT HEPARIN, HEPARIN LOW MOL WEIGHT, HEPARIN LMW, LMW HEPARIN, Heparin, Low-Molecular-Weight, Heparin, Low-Molecular-Weight [Chemical/Ingredient], heparin low molecular weight, low molecular heparin weight, low heparin molecular weight, low molecular weight heparins, anti-xa, lmwh, low molecular weight heparin, anti xa, low-molecular-weight heparin, heparins low molecular weight, Heparin.low molecular weight, Low molecular weight heparin, Low molecular weight heparins, Low molecular weight heparin (product), Low molecular weight heparin (substance) |
Swedish | Heparin, lågmolekylärt |
Czech | heparin nízkomolekulární |
Finnish | Pienimolekyylinen hepariini |
Russian | NIZKOMOLEKULIARNYI GEPARIN, GEPARIN NIZKOMOLEKULIARNYI, ГЕПАРИН НИЗКОМОЛЕКУЛЯРНЫЙ, НИЗКОМОЛЕКУЛЯРНЫЙ ГЕПАРИН |
Japanese | 低分子量ヘパリン, ヘパリン-低分子量 |
Polish | Heparyna LMW, Heparyna o niskim ciężarze cząsteczkowym |
Croatian | NISKOMOLEKULARNI HEPARIN, HEPARIN, NISKOMOLEKULARNI |
Portuguese | HBPM, LMWH, Heparina de Baixo Peso Molecular |
Spanish | heparina de bajo peso molecular (producto), heparina de bajo peso molecular (sustancia), heparina de bajo peso molecular, HBPM, Heparina de Bajo-Peso-Molecular |
French | Héparine bas poids moléculaire, Héparine faible masse moléculaire |
German | Heparin, niedrigmolekulares, LMWH, Niedrigmolekulares Heparin |
Italian | Eparina a basso peso molecolare |
Ontology: Orgaran (C0163842)
Concepts | Pharmacologic Substance (T121) , Organic Chemical (T109) |
MSH | C035838 |
English | Orgaran |
Ontology: tinzaparin (C0216278)
Definition (NCI_NCI-GLOSS) | A drug that is used with another drug, warfarin, to treat blood clots that form deep in the veins and to prevent new blood clots from forming. It is a type of anticoagulant. |
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | C081247 |
SnomedCT | 350469004, 412608008 |
English | tinzaparin, tinzaparin [Chemical/Ingredient], B01AB10, TINZAPARIN, Tinzaparin, Tinzaparin (product), Tinzaparin (substance) |
Spanish | tinzaparina (producto), tinzaparina, tinzaparina (sustancia) |
Ontology: danaparoid (C0259507)
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | C035838 |
SnomedCT | 108992003, 372564002 |
English | danaparoid, DANAPAROID, Danaparoid (product), Danaparoid (substance), Danaparoid |
Spanish | danaparoide (producto), danaparoide (sustancia), danaparoide |
Ontology: Normiflo (C0297267)
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | C093450 |
English | Normiflo |
Ontology: ardeparin (C0297269)
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | C093450 |
SnomedCT | 108989002, 373731006 |
English | ARDEPARIN, ardeparin, ardeparin [Chemical/Ingredient], Ardeparin, Ardeparin (product), Ardeparin (substance) |
Spanish | ardeparina (producto), ardeparina (sustancia), ardeparina |
Ontology: Innohep (C0591649)
Concepts | Pharmacologic Substance (T121) , Carbohydrate (T118) |
MSH | C081247 |
English | Innohep, innohep, Bristol-Myers Squibb brand of tinzaparin sodium, Leo brand of tinzaparin sodium |