6 8 S U P P L E M E N T T O O U T P A T I E N T S U R G E R Y M A G A Z I N E O C T O B E R 2 0 1 7
Deep vein thrombosis (DVT) occurs when a blood clot
forms in one of the large veins, usually in the legs,
leading to either partially or completely blocked
venous circulation. If left untreated, this clot has the
potential to move into the lungs and produce a pul-
monary embolism requiring immediate medical
attention. Here are some obvious — but often over-
looked — red flags to look for when assessing clotting
risks during pre-op patient assessments.
• Personal history of clotting. Patients who've had
venous thrombotic events in the past and who undergo
procedures lasting longer than 1 hour without receiving DVT prophylaxis have a 66% chance
of developing a potentially fatal clot, according to one study. Protect these patients for 1
month after surgery with appropriate anticoagulation therapy after considering bleeding risk.
• Family history of clotting. Patients with parents who've suffered clots are at the high-
est risk, but the dangers are also heightened for patients with a history of clotting in sec-
ond- and third-generation relatives. A patient with a family history of clots who undergoes
a surgery lasting longer than 1 hour is just as likely to develop DVT as a patient with
thrombophilic defects, and that likelihood increases significantly if additional risk factors
are present.
Despite the dangers associated with a family history of clotting, it's the most overlooked
and least asked about risk factor. When my wife needed to undergo an orthopedic proce-
dure, we were never asked once about DVT in general or specifically about a family history
of clotting. The lesson you can take from that experience: Always ask patients about their
personal and family histories of clotting. That's important information to have, and it's not
usually covered in pre-op consults and phone calls.
— Joseph A. Caprini, MD, MS, FACS, RVT
WARNING SIGN
History of Clotting Could Spell Future Trouble
SURGICAL RISK A patient's risk for developing
blood clots increases after surgery.
