The grades of evidence (I-III) and levels of recommendations (A-C) are defined at the end of "Major Recommendations."
The following recommendations are based on good and consistent scientific evidence (Level A):
- Alternatives for thromboprophylaxis for moderate-risk* patients undergoing gynecologic surgery include the following:
- Graduated compression stockings placed before initiation of surgery and continued until the patient is fully ambulatory
- Pneumatic compression devices placed before initiation of surgery and continued until the patient is fully ambulatory
- Unfractionated heparin (5,000 units) administered subcutaneously 2 hours before surgery and every 12 hours after surgery until discharge
- Low-molecular-weight heparin (dalteparin, 2,500 antifactor-Xa units, or enoxaparin, 40 mg) administered subcutaneously, 12 hours before surgery and once a day postoperatively until discharge
- Alternatives for prophylaxis for high-risk* patients undergoing gynecologic surgery, especially for malignancy, include the following:
- Pneumatic compression devices placed before surgery and continued until hospital discharge
- Unfractionated heparin (5,000 units) administered subcutaneously 2 hours before surgery and every 8 hours postoperatively and continued until discharge
- Low molecular weight heparin (dalteparin 5,000 antifactor-Xa units or enoxaparin 40 mg) administered subcutaneously, 12 hours before surgery and once daily postoperatively until discharge
The following recommendations are based on limited scientific evidence (Level C):
- Alternatives for prophylaxis for highest-risk patients include the following:
- Combination prophylaxis (such as the combination of pneumatic compression and either low dose unfractionated heparin or low molecular weight heparin)
- Consideration of continuing low molecular weight heparin prophylaxis as an outpatient for up to 28 days postoperatively
- If administration of low molecular weight heparin 12 hours before surgery is impractical, initial dosing should commence 6 to 12 hours postoperatively.
- Low-risk patients who are undergoing gynecologic surgery do not require specific prophylaxis other than early ambulation.
- Until more evidence is accumulated, patients undergoing laparoscopic surgery should be stratified by risk category (and provided prophylaxis) similar to patients undergoing laparotomy.
*For classification of risk levels for thromboembolism among gynecologic surgery patients, see box and table below:
Venous Thromboembolism Risk Factors
- Surgery
- Trauma (major or lower extremity)
- Immobility, paresis
- Malignancy
- Cancer therapy (hormonal, chemotherapy, or radiotherapy)
- Previous venous thromboembolism
- Increasing age
- Pregnancy and the postpartum period
- Estrogen-containing oral contraception or hormone therapy
- Selective estrogen receptor modulators
- Acute medical illness
- Heart or respiratory failure
- Inflammatory bowel disease
- Myeloproliferative disorders
- Paroxysmal nocturnal hemoglobinuria
- Nephrotic syndrome
- Obesity
- Smoking
- Varicose veins
- Central venous catheterization
- Inherited or acquired thrombophilia
Geerts WH, Pineo GF, Heit JA, Bergqvist D, Lassen MR, Colwell CW, et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004;126(suppl):338S–400S.
|
Table: Risk Classification for Venous Thromboembolism in Patients Undergoing Surgery Without Prophylaxis
Level of
Risk |
Definition |
| Low |
Surgery lasting less than 30 minutes in patients younger than 40 years with no additional risk factors |
| Moderate |
Surgery lasting less than 30 minutes in patients with additional risk factors; surgery lasting less than 30 minutes in patients aged 40 to 60 years with no additional risk factors; major surgery in patients younger than 40 years with no additional risk factors |
| High |
Surgery lasting less than 30 minutes in patients older than 60 years or with additional risk factors; major surgery in patients older than 40 years or with additional risk factors |
| Highest |
Major surgery in patients older than 60 years plus prior venous thromboembolism, cancer, or hypercoagulable state |
Modified from Geerts WH, Pineo GF, Heit JA, Bergqvist D, Lassen MR, Colwell CW, et al. Prevention of venous thromboembolism: the Seventh ACCP Conference on Antithrombotic and Thrombolytic Therapy. Chest 2004;126(suppl):338S–400S.
Definitions:
Grades of Evidence
I Evidence obtained from at least one properly designed randomized controlled trial.
II-1 Evidence obtained from well-designed controlled trials without randomization.
II-2 Evidence obtained from well-designed cohort or case-control analytic studies, preferably from more than one center or research group.
II-3 Evidence obtained from multiple time series with or without the intervention. Dramatic results in uncontrolled experiments also could be regarded as this type of evidence.
III Opinions of respected authorities, based on clinical experience, descriptive studies, or reports of expert committees.
Levels of Recommendations
Level A - Recommendations are based on good and consistent scientific evidence.
Level B - Recommendations are based on limited or inconsistent scientific evidence.
Level C - Recommendations are based primarily on consensus and expert opinion.
