The guidelines suggest Coumadin as an option for knee replacement patients, but they also note that Coumadin may not be as effective as some of the injectable products. Bleeding risk may be lower, however. In contrast to knee replacement, knee arthroscopy does not require routine protection other than early mobilization. The ACCP does recommend the use of prevention for patients who have preexisting blood clots risk and are going to have knee scopes.
Total Hip Replacement
About half of all hip replacement patients who do not receive treatment will develop asymptomatic blood clots, and up to 5% will develop symptomatic blood clots. Mortality from PE occurs in about 1 in 500 hip replacement patients. The ACCP guidelines recommend injectable medicines or Coumadin.
Total Knee Replacement
Without treatment, at least half of knee replacement patients will experience blood clots, up to 10% will develop symptomatic lung clots, and up to 2% will die from lung clots. The ACCP guidelines recommend injectable medicine or Coumadin, with TED hose and SCDs as a possible alternative treatment.
Hip Fracture Surgery
Among orthopedic surgery patients, those undergoing hip fracture surgery (HFS) have the greatest risk of death from lung clots, up to 7.5%. In the absence of prophylaxis, half of HFS patients develop blood clots. The ACCP guidelines recommend prevention with injectable medicines or Coumadin.
The ACCP guidelines were specific to some of the highest risk surgery. However, patients with a family history of blood clots or multiple risk factors should consider prevention.
Timing and Duration of Treatment
In a review of available evidence on the timing of treatment after major orthopedic surgery, administration at 6 hours following surgery is effective and does not increase bleeding risk. The optimal duration of treatment is unclear. According to the ACCP, it should be continued at least 10 days following surgery for knee or hip replacement, or hip fracture surgery. The guidelines also support extended treatment (28 – 35 days) for patients undergoing hip replacement or fracture surgery. Options recommended for extended treatment are injectable medicines or Coumadin.