Background and Objectives Multimodal analgesia, including continuous femoral block, is often used to manage postoperative pain following total knee arthroplasty. To reduce the risk of deep vein thrombosis and pulmonary embolus formation, anticoagulation is also a part of the care for patients who undergo total knee arthroplasty. However, the concurrent use of continuous peripheral nerve block and anticoagulation can lead to hematoma formation. This prospective, single-center, observational study investigated the incidence of hematoma formation, causing neurovascular compromise, for patients with femoral catheters while taking the oral anticoagulant rivaroxaban.

Methods Five hundred four eligible patients consented to participate in this study. A femoral nerve block catheter was inserted before surgery, and a continuous infusion of local anesthetic was continued for 36 to 48 hours postoperatively. Rivaroxaban 10 mg was administered daily, and the femoral catheter was removed 20 hours after a dose of rivaroxaban. Participants were assessed daily to postoperative day 3 for the presence of a hematoma causing neurovascular compromise or ecchymosis formation at the femoral catheter site; sensory and motor functions of the femoral nerve were also assessed.

Results No participant presented with a hematoma causing neurovascular compromise at the femoral catheter site or groin area (upper confidence limit, 3.7). The most common complication was an ecchymosis in the groin or upper thigh, with the highest incidence of ecchymosis formation occurring on postoperative day 3.

Conclusions In this prospective observational study, the concurrent administration of continuous femoral nerve block, the once-daily administration of the anticoagulant rivaroxaban, and the timed removal of the femoral catheter were not associated with hematoma formation resulting in neurovascular compromise at the femoral catheter insertion site or groin area.