Abstract
The introduction of direct thrombin inhibitors in arthroplasty surgery has reignited the debate on the risk of wound complications when using chemical thromboprophylaxis. It has been suggested that direct thrombin inhibitors might lead to an increased risk of systemic and operative site bleeding and wound sepsis when compared to low molecular weight heparin.
In July 2009, departmental thromboprophylaxis policy for patients undergoing hip and knee replacement surgery (including revision) was changed from subcutaneous enoxaparin for the duration of inpatient stay to dabigatran for 10 days (knees) or 28 days (hips) unless contraindidated. In the 2 years prior to policy change, 1091 patients underwent hip or knee arthroplasty (Group 1), with1150 patients undergoing the same procedures in the 2 years following July 2009 (Group 2). A minority of patients were already on warfarin (2% in group 1, 3% in group 2).
This study presents a retrospective analysis of all patients who returned to theatre within 30 days of joint replacement surgery to assess whether the change in unit policy caused any discernible increase in bleeding-related complications.
In group 1, 23/1091 patients (2.1%) returned to theatre within 30 days. 8 were for reasons unrelated to thromboprophylaxis (mainly dislocated hips), 5 for gastrointestinal bleeding (mainly upper GI endoscopy) and 10 for wound complications (haematoma, wound breakdown, or washout of early infection). In group 2, 22 / 1150 patients (1.9%) returned to theatre within 30 days. 12 were for unrelated reasons, 5 for GI bleeding, and 5 for wound complications. The lower return to theatre rate in the second group was not statistically different.
This study, in a large heterogeneous group of patients, suggests that a change from enoxaparin to dabigatran does not increase the incidence of early infection, or the risk of bleeding at the operative site or the gastrointestinal tract.
