Cite as: Cozowics C, Memtsoudis S. International consensus meeting on venous thromboembolism prevention in orthopedic surgery. ASRA Pain Medicine News 2022;47. https://doi.org/10.52211/asra110122.044

Venous thromboembolism (VTE) involves deep venous thrombosis (DVT) and pulmonary embolism (PE) and is a significant complication of orthopedic surgery.^1,2 Primary prevention, initiated during hospitalization, is key to mitigating and managing the significant related disease burden.²

The International Consensus Meeting convened a multidisciplinary task force of nearly 600 renowned experts from 68 countries to evaluate the issue of perioperative thrombosis in orthopedic surgery and to specifically inform best clinical practices with evidence-based guideline recommendations to prevent and manage perioperative VTE. The experts reviewed nearly 100 important patient healthcare questions using systematic, quantitative, and qualitative analyses and followed a consensus process using the Delphi method to develop recommendations that comprehensively address the broad spectrum of perioperative VTE implications. It was the most comprehensive project on preventing perioperative VTE to date.

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The task force strongly recommended to delay elective orthopedic surgery by six months for patients with a recent DVT or PE diagnosis.

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The American Society of Regional Anesthesia and Pain Medicine was one of 135 societies represented on the task force and endorses the guideline recommendations,³ which are summarized here.

Perioperative VTE Risk

Currently, clinicians and providers have no validated scoring system to predict risk for VTE or major bleeding events during orthopedic surgery. In that light, the guideline task force advised that perioperative VTE risk varies based on drivers such as genetic predisposition, increased age, prior VTE history, systemic infection, varicosities, oral contraceptive use, hormonal cancer therapy, long-distance flights, immobilization, and procedures such as polymethyl methacrylate cementation.¹ Surgeons and providers should consider those factors and adjust surgical scheduling, medications, and patient suitability assessments as necessary.

Postoperative VTE Management

Most VTE events develop during the first month after surgery, although the risk persists longer.

Because PE may arise from DVT, the task force recommended treating acute postoperative DVT, particularly when located proximately (popliteal or supra-popliteal). However, because of a low risk of propagation to proximal veins, the task force advised monitoring distal DVT without treatment or treating it with aspirin. The task force strongly recommended to delay elective orthopedic surgery by six months for patients with a recent DVT or PE diagnosis.

Management requires individual assessment of VTE severity and bleeding risk. The task force recommended empirical anticoagulation therapy to reduce associated morbidity for suspected but unconfirmed postoperative VTE only when a timely, image-based diagnosis is not possible. Thrombolysis may be considered in postoperative limb-threatening thrombosis with acute ischemia or in selected patients with symptomatic DVT of the iliofemoral veins exhibiting a high risk for severe post-thrombotic syndrome.

DVT and PE Detection

The optimal imaging modality for detecting upper and lower extremity DVT is venous compression ultrasonography. However, the task force did not advise routine perioperative ultrasound screening for VTE in asymptomatic patients or lower extremity venograms for routine DVT diagnosis. If an iliac or vena cava thrombosis is suspected or venous ultrasound is unfeasible or inconclusive, the task force recommended using computer tomography venography, magnetic resonance venography, or contrast phlebography. Additionally, serologic biomarkers such as D-dimer can be used to detect VTE.

The gold standard modality for PE diagnosis after orthopedic surgery is computed tomography pulmonary angiography, according to the task force. Risk stratify patients with acute PE according to severity of hypoxia, hemodynamic status, and right ventricular dysfunction. Furthermore, investigate PE-related chronic thromboembolic pulmonary hypertension to allow for early treatment, including pulmonary endarterectomy.

VTE Prophylaxis

The guideline task force strongly recommended in-hospital initiation of VTE prophylaxis after major orthopedic surgery that continues for 14–35 days after patient discharge. Evidence to date is insufficient to support the superiority of specific VTE prophylactic agents based on their efficacy; however, aspirin appears to be the most cost effective with the lowest risk of side effects (eg, bleeding).

Data are limited on the comparative effectiveness of various factor Xa inhibitors for the prevention of VTE, but chromogenic anti-Xa assays are most accurate for assessing the serum or plasma activity of factor Xa inhibitors. The task force did not recommend routinely bridging patients on warfarin with unfractionated heparin (UFH) or low–molecular-weight heparin (LMWH), except in certain circumstances (eg, mechanical heart valve).

Among injectable pharmacologic agents, the task force found that fondaparinux has the best efficacy profile for VTE prevention compared to LMWH and UFH with no differences in bleeding risk. For optimal VTE prophylaxis, initiate LMWH 12–24 hours after orthopedic surgery.

Contraindications and Comorbidities

The task force identified patient-related relative and absolute contraindications for VTE prophylaxis. Pharmacologic dose adjustments may be required to prevent major bleeding in renal disease, and UFH or mechanical prophylaxis alone may be preferred if patients are unstable. The task force suggested consulting thrombosis or hematology specialists for bleeding or coagulation disorders, creatinine clearance less than 30 mL per minute, active hepatobiliary disease, significant anemia, thrombocytopenia, or required continuous antiplatelet or anticoagulant therapy.

In patients with atrial fibrillation or a high risk for thromboembolic events, the task force emphasized using anticoagulation therapy as recommended by cardiac societies. Mechanical VTE prophylaxis is most appropriate for patients with bleeding disorders such as hemophilia or Von Willebrand disease. Patients with clotting disorders such as thrombophilia should receive a combination of mechanical and pharmacologic interventions for up to 35 days after major orthopedic surgery. Consider use of inferior vena cava filters for patients with a high thromboembolic risk and concurrent contraindication for chemical anticoagulation.

Postoperative Ambulation and Rehabilitation

Early ambulation reduces the incidence of VTE after orthopedic procedures. In patients requiring strict bed rest, consider any combination of pharmacologic or mechanical prophylaxis depending on the duration of immobilization. The guideline task force also emphasized the efficacy of intermittent compression devices and foot pumps in combination with chemical prophylaxis. To facilitate functional recovery and increase pulmonary functional capacity, do not delay postoperative rehabilitation in patients receiving therapeutic anticoagulation for postoperative DVT or PE.

Antiplatelet and Anticoagulation Therapy

The decision to stop or continue aspirin use perioperatively involves variables such as the patient’s cardiovascular risk profile, nature of the surgery, and risk for bleeding. The guideline task force recommended that aspirin use for cardiovascular disease should not be routinely stopped in patients undergoing orthopedic procedures unless contraindicated. In patients with cardiovascular disease, the risk of thrombotic events after acute aspirin withdrawal outweighs the risk of bleeding complications following surgery.

For patients on chronic anticoagulation regimens, the task force recommended discontinuing acenocoumarol for three days, warfarin and fluindione for five days, and phenoprocoumon for seven days prior to elective orthopedic surgery. Stop use of direct acting oral anticoagulants, including apixaban, edoxaban, dabigatran, and rivaroxaban, at least two days prior to elective surgery and possibly longer if creatinine clearance is reduced. Consider bridging chronic anticoagulation in patients with prosthetic heart valves.

Conclusion

The international consensus meeting guideline provides an up-to-date summary of current evidence with international expert consensus on best practices for VTE prophylaxis. Because of a lack of clinical symptoms, challenges in VTE reporting persist, and the task forced delineated topics with low-quality scientific evidence. Nevertheless, the current recommendations provide important guidance on clinical strategies to mitigate the perioperative burden of VTE-related morbidity and mortality in orthopedic surgery.  

Crispiana Cozowicz, MD, is an anesthesiology resident in the department of anesthesiology, perioperative medicine, and intensive care medicine at Paracelsus Medical University in Salzburg, Austria.

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Stavros G. Memtsoudis, MD, PhD, MBA, is a clinical professor of anesthesiology and public health, director of critical care services, and senior scientist in the department of anesthesiology, critical care, and pain management at Weill Cornell Medical College’s Hospital for Special Surgery in New York, NY.

References

1. Granziera S, Cohen AT. VTE primary prevention, including hospitalised medical and orthopaedic surgical patients. Thromb Haemost. 2015;113:1216–1223. https://doi.org/10.1160/th14-10-0823 
2. Majima T, Oshima Y. Venous thromboembolism in major orthopedic surgery. J Nippon Med Sch. 2021;88:268–272. https://doi.org/10.1272/jnms.jnms.2021_88-418 
3. ICM-VTE General Delegates. Recommendations from the ICM-VTE: General. J Bone Joint Surg Am. 2022;104:4–162. https://doi.org/10.2106/jbjs.21.01531