There are many risk factors that may influence the patient’s ability to develop DVT.


  • All patients undergoing major surgical intervention for malignant disease should be considered for thromboprophylaxis.
  • Patients undergoing laparotomy, laparoscopy, or thoracotomy Lasting greater than 30 min should receive pharmalogical thromboprophylaxis with either low-dose UFH or LMWH unless Contraindicated because of a high risk of bleeding or active bleeding.
  • Prophylaxis should be commenced preoperatively, or as early as possible in the postoperative period.

More than half of the DVT’s that develop may be “silent”. On your admission form for surgery the DVT prophylaxis will be indicated as a routine unless there are reasons to omit the drug prior to surgery. This usually may be because the anesthetist would like to place an epidural catheter for pain control. These will be discussed.