- Undergoing abdominal surgery (any surgery between the diaphragm and pelvic floor)
lasting longer than 45 minutes (duration from anesthesia induction to surgical
closure)

- Over 40 years of age

Inclusion Criteria:

- Undergoing abdominal surgery (any surgery between the diaphragm and pelvic floor)
lasting longer than 45 minutes (duration from anesthesia induction to surgical
closure)

- Over 40 years of age

- Subject who had signed the informed consent.

Exclusion Criteria:

- Active, clinically significant bleeding

- Documented congenital or acquired bleeding tendency/disorders

- Active ulcerative gastrointestinal disease unless the reason for the present surgery.

- Recent intracranial hemorrhage or recent (less than 3 months prior to randomisation)
brain, spinal, or ophthalmologic surgery.

- Indwelling intrathecal or epidural catheters for more than 6 hours after surgical
closure.

- Subjects who had a traumatic puncture or unusual difficulty in applying the catheter

- Known cerebral metastasis,

- Subjects in whom hemostasis had not been established 6 hours after surgical closure,

- Current thrombocytopenia,

- Bacterial endocarditis

- Creatinine level above 2.0 mg/dL (180 μmol/L) in a well-hydrated subject,

- Documented hypersensitivity to contrast media,

- Use of any contraindicated drug that could not be combined with the injection of
contrast medium,

- Patent with evidence of leg ischemia caused by peripheral vascular disease, unable to
undergo IPC and unable to wear Elastic Stockings.

Exclusion criteria related to trial methodology:

- Mental disorders that could interfere with study participation and/or failure to give
written informed consent to take part in the study,

- Subject's life expectancy < 6 months,

- Clinical sign of DVT and/or history of recent DVT,

- Participation in any other therapeutic drug study or a device study evaluating DVT
prophylaxis within 90 days preceding inclusion,

- Previous participation in a study of fondaparinux sodium,

- Known hypersensitivity to fondaparinux and its excipients,

- Current addictive disorders that could interfere with study participation,

- Administration of heparin, heparinoids, LMWH, oral anticoagulants, dextrans, hirudin,
fibrinolytic agents or drugs blocking glycoprotein platelet receptors (GPIIb-IIIa)
during the screening period, i.e., from admission to surgery,

- Subjects for whom anticoagulant therapy was contraindicated or who had, due to
concomitant disease, an indication for oral anticoagulant or heparins (including
LMWH) and who could not discontinue those treatments,

- Women of child-bearing potential: women not using an appropriate contraceptive method
during the whole duration of study participation ,

- Subject with body weight <50 kg,

- Subjects, who in the opinion of the investigator, required a pharmacological
prophylaxis in addition to intermittent pneumatic compression,

- Known pregnancy and / or women who intended to breastfeed,

- Subjects undergoing vascular surgery such as aorto-femoral bypass graft