Staff Resources

Risk Stratification & VTE Prophylaxis Protocol

For elective lower-extremity (hip & knee) arthroplasty · provider reference

Goals

  • Reduce the incidence of pulmonary embolism.
  • Reduce the incidence of symptomatic DVT.
  • Limit the side effects of chemoprophylaxis (wound drainage, infection risk, bleeding).

Risk Stratification

Bleeding risk Standard risk Elevated VTE risk
Bleeding disorder
Past complication on aspirin, Lovenox, warfarin, or a DOAC
History of hemorrhagic stroke
Chemoprophylaxis otherwise contraindicated
No history of VTE
No history of a bleeding disorder
Concurrent HRT use
Inactive malignancy, not on chemotherapy/cancer treatment
Prolonged immobility
Prior VTE (any type or timing)
Active malignancy or chemotherapy
Hypercoagulable state (Factor V Leiden, Protein C/S deficiency)
BMI > 40

Proposed Protocol

All groups: intermittent pneumatic compression (SCDs) in hospital; TED stockings are not required; mobilize POD 0 and at least 3× daily thereafter; VTE-prophylaxis education pre-op, in hospital, and at discharge.

For patients NOT on an anticoagulant/antiplatelet before surgery:

Bleeding risk Standard risk Elevated VTE risk
Mechanical only — portable SCDs ordered pre-op and available at discharge
No chemoprophylaxis
Aspirin 81 mg BID
2 weeks (TKA) / 4 weeks (THA)
Start POD 0 in the evening
Add a PPI if on aspirin + any NSAID
Rivaroxaban (Xarelto) 10 mg daily, start POD 1 AM
TKA: × 14 days (2 weeks)
THA: × 14 days, then aspirin 81 mg BID × 14 days (4 weeks total)

Aspirin allergy (otherwise standard-risk): use the elevated-risk agent (rivaroxaban) as the alternative.

For patients already on an anticoagulant/antiplatelet: warfarin, a DOAC, or aspirin may serve as postoperative VTE prophylaxis if the patient was on it before surgery. Plavix alone should not serve as VTE prophylaxis.

Agent Stop Restart Bridging
Warfarin ^ 5 days prior (goal INR < 1.25) POD 0 evening Prefer none unless directed by PCP/cardiology
DOAC ^ 3 days prior POD 1 AM Prefer none unless directed
Plavix ^ # 5 days prior POD 1 AM Prefer none unless directed
Aspirin OK to continue Minimum dose 81 mg BID

^ A cardiologist or primary care provider must approve any temporary hold of these agents.   # Start aspirin 81 mg BID on POD 0 as VTE prophylaxis after surgery.

Tranexamic Acid (TXA)

  • TXA decreases bleeding and is not a pro-thrombotic agent.
  • Give a single 1 g preoperative dose before incision to most patients — except those with CrCl < 30, TXA allergy, or active/recent VTE (within 3 months).

Duplex Ultrasonography (DUS)

  • Per AAOS guidance, recommend against routine preoperative DUS.
  • In patients with known chronic VTE or preoperative unilateral leg swelling, preop DUS may help establish a baseline.
  • Unilateral swelling, bruising, and calf/thigh tenderness are common and normal after TKA/THA and are not reliable predictors of VTE — do not use them as indications for DUS.
  • Do not order DUS after hip/knee arthroplasty unless there is high clinical suspicion by an experienced provider; ideally the attending surgeon, that surgeon's PA, or the on-call surgeon approves it.

Documentation

Surgeons must clearly state the DVT-prophylaxis plan in the last paragraph of the operative report so it is accessible to anyone caring for the patient postoperatively.

Questions about this protocol? Call the clinic where the surgery was performed — Dr. Allred is happy to talk through the plan.