70 – Should a patient with active lower extremity DVT undergo an orthopaedic procedure?

Michael Meghpara, James Purtill, Paul Tornetta III, Felix Vilchez.

Response/Recommendation: There is limited scientific evidence to support the safety of orthopaedic surgery in a patient with an active deep venous thrombosis (DVT) or pulmonary embolism (PE); its management must be individualized based on the patient history, procedure, extent of the DVT/PE, physiologic parameters, and the risk of bleeding during and after surgery.

Strength of Recommendation: Limited.

Rationale: Acute or active venous thromboembolism (VTE) in the form of DVT or PE may be present in a patient undergoing both elective and emergent orthopaedic procedures. While no formal cutoff exists, studies have often utilized 21 days from the onset of symptoms to define acute VTE1. When VTE occurs prior to surgical intervention, the need for anticoagulation or other intervention to treat the VTE and to avoid further associated morbidity must be incorporated into the perioperative orthopaedic management.

If the surgical intervention is not time-sensitive, then it should be delayed for as long as possible until the DVT/PE is treated and/or resolved. When a patient undergoing elective surgery develops VTE prior to surgery, due to a recurrence rate of nearly 40% within the first 4 weeks, surgery should be delayed at least one month2. The longer surgery can be delayed, the lower the risk for VTE recurrence3–5.

Patients undergoing elective orthopaedic procedures, such as hip or knee arthroplasty are already at high risk for venous thromboembolism6. The American Academy of Orthopaedic Surgeons (AAOS) guidelines report that a history of VTE significantly increases the risk in patients undergoing elective arthroplasty, and several studies cite additional risk factors such as: middle or old age, trauma, body mass index (BMI), cholesterol, high-density lipoprotein, apolipoprotein A, malignancy, prolonged surgery or contraceptive use, hormone therapy and pregnancy in women79. The risk of DVT is also increased in patients undergoing spinal surgery. Zervos, et al., reported that patients with a history of DVT who underwent elective spinal surgery have a higher risk of developing symptomatic DVT postoperatively10.

However, the surgical intervention may be time-sensitive and/or emergent. For example, patients with hip fractures have optimal outcomes and decreased morbidity and mortality when operative intervention is delivered within the first 24-48 hours11–14. Patients with hip fracture are known to have an incidence of DVT ranging from 9 to 13% preoperatively15. It may be necessary to surgically treat the hip fracture in the face of an active/acute DVT/PE. Another group of patients with time-sensitive surgical issues are those with open fractures and orthopaedic infections. Interestingly, fractures and infections both trigger an inflammatory cascade which may make patients prone to developing DVT16,17.

Sixty percent of DVT occur in the proximal venous system and 40% occur distally18. Distal DVT that occur in the gastrocnemius or soleal veins have a low probability of propagating proximally or developing into a PE19,20. The evidence on whether to treat a distal DVT varies21 and the use of anticoagulants for isolated distal DVT in otherwise low-risk patients may not be superior to either a placebo or non-treatment22–24. With no treatment, close observation with ultrasound at two weeks is suggested25. Proximal DVT, however, have a higher association with PE26–28. In addition to the increased risk of developing PE (6% – 32%) as an acute complication or post-thrombotic syndrome (25% – 38%) and venous ulceration (9.8%) as chronic complications29–32; progression may also be associated with increased morbidity with mortality rates up to 40%33–35.

In patients with acute VTE, various agents can be utilized to achieve therapeutic anticoagulation to prevent further clot development. Warfarin and newer direct-acting oral anticoagulants (DOAC) have limited utility. Warfarin anticoagulation would need to be bridged with heparin peri-operatively while DOAC have limited anticoagulation reversal options. Treatment with unfractionated heparin (UFH) or low-molecular-weight heparin (LMWH) may be more useful for patients with acute VTE requiring non-elective surgery36. In the setting of an acute or active DVT or PE, stopping UFH or LMWH treatment for a period of time for a patient to undergo surgery is feasible and carries low risk37,38. To limit undesirable anticoagulant effects intraoperatively, LMWH should be held for 24 hours or reduced by 50% the evening prior to surgery3,36 while UFH should be discontinued 4-6 hours prior to procedure39. All patients should receive mechanical prophylaxis prior to and during surgery which can decrease the risk of VTE by up to 60%4,40. However, mechanical compression should be avoided in a limb with a DVT due to the potential risk of embolizing a clot41. Postoperatively, patients are at increased risk of bleeding, and anticoagulation is often restarted once post-procedural hemostasis is ensured. Data related to the optimal start time of prophylaxis is limited36. Based on the findings of the PROSPECT trial, a multicenter prospective study of 260 patients, restarting enoxaparin 12-24 hours postoperatively resulted in bleeding in 20% of patients undergoing major surgery42. Patients may be bridged with UFH or LMWH to warfarin or DOAC, beginning 24 to 72 hours after major surgery and 18-14 hours after minor surgery36,43–46.

Use of an inferior vena cava (IVC) filter should be considered when a patient has contraindications to anticoagulation or a history of recurrent VTE on prophylaxis4. Although controversial, the utilization of IVC filters has increased over the years, especially with the advent of percutaneous insertion47,48. IVC filters in high risk patients with an acute proximal DVT have been shown to initially prevent acute PE49, and can capture a thrombus in up to 13% of patients postoperatively50. Although rare, complications associated with IVC filters increase after 30 days and include filter migration, fracture, vena cava perforation, and vena cava occlusion51–53.

If immediate intervention is required in an unstable patient with cardiac strain identified by echocardiogram, the benefits associated with more invasive options such as thrombolysis or embolectomy may outweigh the risks to a surgical patient28,56,55,56. Systemic thrombolysis may significantly increase the risk of bleeding, however thrombolysis may prevent further hemodynamic decompensation from VTE57–59. While no specific studies exist about performing thrombolysis in orthopaedic patients, a few studies60–62 show the safety of thrombolysis in post-surgical patients with one report suggesting the use of a thigh tourniquet to prevent surgical site hemorrhage until the thrombolytic agent was no longer active63. Another option in patients with pulmonary embolism is catheter-directed thrombolysis which has demonstrated effectiveness in improving right ventricular strain and pulmonary artery pressure with no risk of major bleeding64–66.

While there is limited high-level evidence to support definitive general recommendations, patients with DVT or PE are not advised to undergo elective surgery due to the high surgical risk associated with increased mortality. However, its management prior to an emergent orthopaedic procedure varies based on individual patient factors with perioperative implications of each clinical scenario.

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