Thromboembolism is a real threat after hip, pelvic, and large bone fractures and repairs as well as knee and hip replacements. A thromboembolism will also put the brakes on any RTW plans as will the long need for anticoagulants should a clot DVT (deep vein thrombosis) develop. So when should anticoagulant therapy start and who should have it? The short answer is immediately after injury and everyone who is at risk.

High Risk of Death: Approximately 350,000 hip fractures occur annually, with an anticipated increase to 500,000 by 2040. Death rates of 4% to 6% during hospitalization and 14% to 36% at 1 year are notably higher than the 1% to 1.3% for patients undergoing total hip or knee replacements.

Most hip fractures are treated surgically, and the American College of Chest Physicians (ACCP) puts hip fracture surgery in the highest risk category for VTE (venous thromboembolism). Prospective randomized controlled trials have shown that without prophylaxis the rate of DVT in patients with hip fracture ranges from 46% to 75% using venography. A British study looking at 580 consecutive patients with femoral neck fractures reported fatal pulmonary embolism in 4% of patients not receiving prophylaxis. Clearly, all patients with hip fracture need prophylaxis against VTE.

Doctors should not delay starting prophylaxis. Patients are at risk of VTE while they wait 24-48 hours or more for surgery.

The Dangers of Delay: We feel it is important to begin preventive anticoagulation immediately, since in many cases patients do not undergo surgery until 24 to 48 hours after arrival at the hospital, leaving them unprotected against the risks of VTE during that time. Delay in presentation to the hospital after hip fracture and delay in time to surgery are associated with a significantly increased risk of DVT. One study showed that the incidence of DVT in patients who did not present to the hospital until more than 48 hours after hip fracture was 55%, compared with 6% in those presenting sooner than 48 hours.

These studies imply that the risk of VTE in hip fracture patients starts at the time of injury rather than after surgical repair, although one may argue that this reflects the increased underlying co-morbidity in those in whom surgery is delayed.

It appears that risk of clots is increasing and I am often asked by adjusters if the blood clots are work related. If they are related to a surgery or a fracture then most likely it is a complication of the procedure or fracture. Delays with starting prophylaxis can be very risky. This is a when a nurse case manager can be your eyes and ears to make sure things are being managed by the provider and that the patient understands the risk of non-compliance with anticoagulant therapy.

Reference: Cleveland Clinic Med Ed