30
Venous Thromboembolism Prophylaxis in Orthopedic Surgery Prepared for: Agency for Healthcare Research and Quality (AHRQ) www.ahrq.gov

Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Embed Size (px)

DESCRIPTION

Venous Thromboembolism Prophylaxis in Orthopedic Surgery. Prepared for: Agency for Healthcare Research and Quality (AHRQ) www.ahrq.gov. Outline of This Presentation. The comparative effectiveness review (CER) process Overview of venous thromboembolism (VTE) and orthopedic surgery - PowerPoint PPT Presentation

Citation preview

Page 1: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Venous Thromboembolism Prophylaxis in Orthopedic

SurgeryPrepared for:

Agency for Healthcare Research and Quality (AHRQ)

www.ahrq.gov

Page 2: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

The comparative effectiveness review (CER) process

Overview of venous thromboembolism (VTE) and orthopedic surgery

VTE prophylaxis Results from the CER Summary of conclusions Gaps in knowledge What to discuss with your patients

Outline of This Presentation

Page 3: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Topics are nominated through a public process, which includes submissions from health care professionals, professional organizations, the private sector, policymakers, the public, and others.

A systematic review of all relevant clinical studies is conducted by independent researchers, funded by AHRQ, to synthesize the evidence in a report summarizing what is known and not known about the select clinical issue. The research questions and the results of the report are subject to expert input, peer review, and public comment.

The results of these reviews are summarized into Clinician and Consumer Research Summaries for use in decisionmaking and in discussions with patients. The research reviews and the full report are available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Agency for Healthcare Research and Quality (AHRQ) Comparative Effectiveness Review (CER) Development

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 4: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

The strength of evidence was classified into four broad categories:

Rating the Strength of Evidence From the Comparative Effectiveness Review

AHRQ. Methods Guide for Effectiveness and Comparative Effectiveness Reviews. April 2012. Available at www.effectivehealthcare.ahrq.gov/ehc/ products/60/318/MethodsGuide_Prepublication-Draft_20120409.pdf.Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 5: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Major orthopedic surgery including total hip replacement (THR), total knee replacement (TKR), and hip fracture surgery carries a risk for venous thromboembolism (VTE).

Without prophylaxis, historic data suggest deep vein thrombosis (DVT) occurs in 40–60 percent of cases in the 7–14 days following surgery.

With routine use of thromboprophylaxis, symptomatic VTE in patients within 3 months of surgery is approximately 1.3–10 percent.

Prophylactic strategies may decrease the risk of VTE, DVT, and pulmonary embolism.

The main limitation of pharmacological VTE prophylaxis is the risk of bleeding, which historically occurs in 1–3 percent of THR and TKR surgeries.

Thromboprophylaxis in Major Orthopedic Surgery

American Academy of Orthopaedic Surgeons. Guideline on preventing venous thromboembolic disease in patients undergoing elective hip and knee arthroplasty. Available at www.aaos.org/research/guidelines/VTE/VTE_guideline.asp .

Page 6: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

A variety of strategies to prevent venous thromboembolism are available: Pharmacological

Oral antiplatelet agents Injectable low-molecular-weight heparins Injectable unfractionated heparin Injectable or oral factor Xa inhibitors Injectable or oral direct thrombin inhibitors Oral vitamin K antagonists

Mechanical modalities Graduated compression Intermittent pneumatic compression Venous foot pump

Combinations of these

Preventing Venous Thromboembolic Events in Major Orthopedic Surgery

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 7: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

The magnitude of benefit and harms in contemporary practice and evaluation of pharmacological agents or devices available within the United States amongst the orthopedic surgery population is not well known.

Additionally, the influence of these factors in contemporary practice needs to be systematically evaluated: The impact of duration of prophylaxis on outcomes Whether dual prophylactic therapy is superior to single-

modality therapy The comparative effectiveness of different

pharmacological or mechanical modalities The risks of VTE, PE, and DVT and the causal link between

DVT and PE.

Establishing the Need for a Systematic Review of VTE Prophylaxis in Orthopedic Surgery

American Academy of Orthopaedic Surgeons. Guideline on preventing venous thromboembolic disease in patients undergoing elective hip and knee arthroplasty. Available at www.aaos.org/research/guidelines/VTE/VTE_guideline.asp .

Page 8: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Baseline Postoperative Risk of Venous Thromboembolism and

Bleeding Outcomes in Contemporary Practice

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 9: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Baseline Postoperative Risks of VTE Outcomes in the Absence of Pharmacological Prophylaxis

Outcome Total Hip Replacement

Strength of Evidence(THR)

Total Knee

Replacement

Strength of Evidence(TKR)

Pulmonary embolism

6% Low 1% Low

Deep vein thrombosis

39% Low 46% Low

Major bleeding 1% Moderate 3% Low

Minor bleeding 5% Low 5% Moderate

Most of the literature evaluated total hip and total knee replacement surgeries with very little evaluation of hip fracture surgery. The baseline risk of venous thromboembolism and bleeding outcomes in the absence of pharmacological prophylaxis are as follows:

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 10: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological or Mechanical

Thromboprophylaxis Versus No Thromboprophylaxis

Pharmacological versus no pharmacological prophylaxis

Mechanical versus no thromboprophylaxis

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 11: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Versus No Pharmacological Prophylaxis

Outcome Magnitude of Effect

RR/OR (95% CI), NNT/NNH

Strength of Evidence

DVT Decreases risk by 44%

RR 0.56 (0.47 to 0.68), NNT 3 to 33

Moderate

Proximal DVT Decreased risk by 47%

RR 0.53 (0.39 to 0.74), NNT 4 to 213

High

Distal DVT Decreased risk by 41%

RR 0.59 (0.42 to 0.82),NNT 8 to 35

High

Asymptomatic DVT

Decreased risk by 48%

RR 0.52 (0.40 to 0.69),NNT 4 to 6

Moderate

Symptomatic VTE NR

Major VTE Decreased risk by 79%

RR 0.21 (0.05 to 0.95),NNT 19 to 22

Low

PE No difference OR 0.38 (0.13 to 1.07)

Low

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; NNH = number needed to harm (the calculated range); NNT = number needed to treat (the calculated range; NR = not reported or insufficient evidence to permit conclusions; OR = odds ratio; RR = relative risk

Page 12: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Versus No Pharmacological Prophylaxis: Adverse Effects

Outcome Magnitude of Effect

RR/OR (95% CI),

NNT/NNH

Strength of Evidence

Major Bleeding No difference RR 0.74 (0.36 to 1.51)

Moderate

Minor Bleeding Relative risk is higher for pharmacological prophylaxis by 67%

RR 1.67 (1.18 to 2.38),NNH 30 to 75

High

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; NNH = number neededto harm; NNT = number needed to treat; OR = odds ratio; RR = relative risk

Page 13: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Mechanical prophylaxis significantly decreased deep vein thrombosis (DVT; results from one randomized controlled trial; strength of evidence not rated).

The risk for proximal or distal DVT was not significantly different (results from one randomized controlled trial; strength of evidence not rated).

Data are not available to evaluate the comparative effect of mechanical prophylaxis versus no prophylaxis on other outcomes.

Comparative Effectiveness of Mechanical Prophylaxis Versus No Thromboprophylaxis

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 14: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological and Mechanical

Prophylaxis Agents

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 15: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Agents: LMWH Versus UFH

Magnitude of Effect; Risk/Odds (95% CI), NNT/NNH (SOE)

Comparators

DVT Proximal DVT

Symptomatic VTE

PE Major Bleeding

Minor Bleedin

g

Heparin-induced Thromb

o-cytopeni

a

LMWH vs. UFH

Decreased risk by 20%; RR 0.80 (0.65 to 0.99), NNT 12 to 100 (SOE = Moderate)

Decreased risk by 40%; RR 0.60 (0.38 to 0.93), NNT 14 to 50 (SOE = High)

NR Decreased odds by 52%; OR 0.48 (0.24 to 0.95), NNT 8(SOE = Moderate)

Decreased odds by 35%;

OR 0.57 (0.37 to 0.88), NNT 41(SOE = High)

No difference;RR 0.90 (0.63 to 1.28) (SOE = Moderate)

Decreased odds by 88%; OR 0.12 (0.03 to 0.43), NNT 34 to 202(SOE = Moderate)

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; DVT = deep vein thrombosis; LMWH = low-molecular-weight heparin; major bleeding = for example, bleeding leading to greater transfusion requirements and/or reoperation; minor bleeding = for example, surgical site bleeding, bleeding leading to infection, or bleeding leading to transfusion but not reoperation; NNH = number needed to harm (the calculated range); NNT = number needed to treat (the calculated range); NR = not reported or insufficient evidence to permit conclusions; OR = odds ratio; PE = pulmonary embolism; RR = relative risk; SOE = strength of evidence rating; UFH = unfractionated heparin; VTE = venous thromboembolism

Page 16: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Agents: Enoxaparin Versus Fondaparinux

Magnitude of Effect; Risk/Odds (95% CI), NNT/NNH (SOE)

Comparators

DVT Proximal

DVT

Symptomatic VTE

PE Major Bleeding

Minor Bleeding

Enoxaparinvs. fondaparinux

Relative risk is higher for enoxaparinby 99%;RR 1.99 (1.57 to 2.51), NNH 13 to 26(SOE = Moderate)

Odds are higher for enoxaparin by 219%;OR 2.19(1.52 to 3.16), NNH 44 to 122 (SOE = Low)

No difference; OR 0.70(0.48 to 1.02) (SOE = Low)

No difference; OR 3.34 (0.58 to 19.32) (Not rated)

Decreased odds by 35%;OR 0.65 (0.48 to 0.89),NNT 74 to 145 (SOE = Moderate)

Decreased odds by 43%; OR 0.57 (0.35 to 0.94), NNT 31 to 60 (SOE = Low)

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; DVT = deep vein thrombosis; major bleeding = for example, bleeding leading to greater transfusion requirements and/or reoperation; minor bleeding = for example, surgical site bleeding, bleeding leading to infection, or bleeding leading to transfusion but not reoperation; NNH = number needed to harm (the calculated range); NNT = number needed to treat (the calculated range); OR = odds ratio; PE = pulmonary embolism; RR = relative risk; SOE = strength of evidence rating; VTE = venous thromboembolism

Page 17: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Agents: LMWH Versus Warfarin

Magnitude of Effect; Risk/Odds (95% CI), NNT/NNH (SOE)Comparat

orsDVT Proximal

DVT

Symptomatic

VTE

PE Major Bleeding

Minor Bleeding

LMWH vs. warfarin

Decreased risk by 34%;RR 0.66(0.55 to 0.79), NNT 6 to 13 (SOE = Low)

No difference; RR 0.63(0.39 to 1.00)(SOE = Low)

No difference; OR 1.00 (0.69 to 1.46) (SOE = Low)

No difference;OR 1.11 (0.57 to 2.19)

(SOE = Moderate)

Odds are higher for LMWH by 92%;OR 1.92(1.27 to 2.91), NNH 57 to 220(SOE = High)

Relative risk is higher for LMWHby 23%; RR 1.23(1.06 to 1.43), NNH 18 to 218 (SOE = Moderate)

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; DVT = deep vein thrombosis; LMWH = low-molecular-weight heparin; major bleeding = for example, bleeding leading to greater transfusion requirements and/or reoperation; minor bleeding = for example, surgical site bleeding, bleeding leading to infection, or bleeding leading to transfusion but not reoperation; NNH = number needed to harm (the calculated range); NNT = number needed to treat (the calculated range); OR = odds ratio; PE = pulmonary embolism; RR = relative risk; SOE = strength of evidence rating; VTE = venous thromboembolism

Page 18: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Pharmacological Prophylaxis Agents: UFH Versus Desirudin

Magnitude of Effect; Risk/Odds (95% CI), NNT/NNH (SOE)

Comparators

DVT Proximal DVT

Symptomatic

VTE

PE Major Bleedin

g

Minor Bleedin

g

UFH vs. desirudin

Relative risk is higher for UFH

by 231%;RR 2.31 (1.34 to 4.00), NNH 5 to 11 (SOE = Moderate)

Odds are higher for UFH by 477%; OR 4.74 (2.99 to 7.49), NNH 11 (SOE = Moderate)

NR No difference; OR 3.23(0.56 to 18.98)(SOE = Low)

NR NR

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; DVT = deep vein thrombosis; major bleeding = for example, bleeding leading to greater transfusion requirements and/or reoperation; minor bleeding = for example, surgical site bleeding, bleeding leading to infection, or bleeding leading to transfusion but not reoperation; NNH = number needed to harm (the calculated range); NR = not reported or insufficient evidence to permit conclusions; OR = odds ratio; PE = pulmonary embolism; RR = relative risk; SOE = strength of evidence rating; UFH = unfractionated heparin; VTE = venous thromboembolism

Page 19: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Warfarin decreased the risk of proximal deep vein thrombosis (DVT) by 63 percent when compared with mechanical prophylaxis. Strength of Evidence = Moderate

Patients on aspirin had higher rates of DVT when compared with those using only mechanical prophylaxis. Strength of Evidence = Moderate

Pharmacological plus mechanical prophylaxis reduced the risk of DVT by 52 percent when compared with pharmacological prophylaxis alone. Strength of Evidence = Moderate

Comparative Effectiveness of Pharmacological and Mechanical Prophylaxis

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 20: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Comparative Effectiveness of Prolonged (≥28 Days) Versus

Standard (7–10 Days) Pharmacological Prophylaxis

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 21: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Prolonged (≥28 Days) Versus Standard (7–10 Days) Pharmacological Prophylaxis: Clinical Outcomes

Prolonged Versus Standard-Duration Prophylaxis

Magnitude of Effect

Risk/Odds (95% CI)

NNT/NNH Strength of Evidence

Symptomatic VTE

Decreasedrisk by 62%

RR 0.38(0.19 to 0.77)

NNT 8 to 54

Moderate

PE Decreasedodds by 87%

OR 0.13(0.04 to 0.47)

NNT 24 to 232

High

Nonfatal PE Decreased odds by 87%

OR 0.13 (0.03 to 0.54)

NNT 58 Moderate

DVT Decreased risk by 63%

RR 0.37 (0.21 to 0.64)

NNT 5 to 32

Moderate

Asymptomatic DVT

Decreased risk by 52%

RR 0.48 (0.31 to 0.75)

NNT 8 to 65

High

Symptomatic DVT

Decreased odds by 64%

OR 0.36 (0.16 to 0.81)

NNT 27 to 79

High

Proximal DVT Decreasedrisk by 71%

RR 0.29(0.16 to 0.52)

NNT 9 to 71

HighSobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 22: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Prolonged (≥28 Days) Versus Standard (7–10 Days) Pharmacological Prophylaxis: Adverse Effects

Prolonged Versus Standard-DurationProphylaxis

Magnitude of Effect

Risk/Odds (95% CI)

NNT/NNH Strength of Evidence

Major Bleeding No difference OR 2.18(0.73 to 6.51)

Low

Minor Bleeding Odds are higher for prolonged prophylaxis by 244%

OR 2.44(1.41 to 4.20)

NNH 11 to 118

High

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Abbreviations: 95% CI = 95-percent confidence interval; major bleeding = for example, bleeding leading to greater transfusion requirements and/or reoperation; minor bleeding = for example, surgical site bleeding, bleeding leading to infection, or bleeding leading to transfusion but not reoperation; NNH = number needed to harm (the calculated range); NNT = number needed to treat (the calculated range); OR = odds ratio

Page 23: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Patient or Surgical Characteristics That May Affect

the Risk ofVenous Thromboembolism

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 24: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Patients who receive general anesthesia may have a higher risk of deep vein thrombosis (DVT) than those who receive regional anesthesia; however, there were no differences in proximal or symptomatic DVT. Strength of Evidence = Low

No difference in risk of DVT or proximal DVT was found among patients receiving cemented versus noncemented arthroplasty. Strength of Evidence = Low

Observational data suggest that patients with congestive heart failure were at an increased risk for symptomatic, objectively confirmed venous thromboembolism when compared with those without it. Strength of Evidence = Moderate

Characteristics That May Affect Risk of Venous Thromboembolism: Results

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 25: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

The oral direct factor Xa inhibitor, rivaroxaban, was approved by the FDA for preventing DVT, which may be associated with PE, in patients undergoing THR or TKR surgery.

This decision was based, in part, on the findings of four phase III trials known as the Regulation of Coagulation in Orthopedic Surgery to Prevent Deep Venous Thrombosis and Pulmonary Embolism (RECORD) trials: RECORD 1, RECORD 2, RECORD 3, and RECORD 4. They compared various regimens of rivaroxaban and

enoxaparin in THR or TKR surgery. The primary efficacy outcome was composite DVT,

nonfatal PE, or all-cause mortality. The primary safety outcome was major bleeding.

Summary of the RECORD Trials

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 26: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

RECORD 1 and 2 trials (THR): There was reduced risk of the primary efficacy outcome with prolonged

rivaroxaban (started 6–8 hours postoperatively, for 35 ± 4 days) when compared with enoxaparin given as either prolonged (started evening before surgery, for 36 ± 4 days) or standard-duration (started evening before surgery, for 13 ± 2 days) prophylaxis. RECORD 1: The primary efficacy outcome occurred in 1.1 percent of

patients given rivaroxaban and 3.7 percent of patients given enoxaparin (ARR = 2.6%; 95% CI, 1.5 to 3.7; P < 0.001).

RECORD 2: The primary efficacy outcome occurred in 2.0 percent of patients given rivaroxaban and 9.3 percent of patients given enoxaparin (ARR = 7.3%; 95% CI, 5.2 to 9.4; P < 0.0001).

RECORD 3 and 4 trials (TKR): Rivaroxaban decreased the risk of the primary efficacy outcome when

compared with enoxaparin. RECORD 3: The primary efficacy outcome occurred in 9.6 percent of

patients given rivaroxaban and 18.9 percent of patients given enoxaparin (ARR = 9.2%; 95% CI, 5.9 to 12.4; P < 0.001).

RECORD 4: The primary efficacy outcome occurred in 6.9 percent of patients given rivaroxaban and in 10.1 percent of patients given enoxaparin (ARR = 3.19%, 95% CI, 0.71 to 5.67; P = 0.0118).

In all four trials, there were no significant differences in the risk for the primary safety outcome of major bleeding or for the risks of mortality or minor bleeding outcomes.

Summary of Outcomes From the RECORD Trials

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 27: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Estimated native (i.e., without pharmacological prophylaxis) incidence of DVT after THR and TKR surgery was 39 percent and 46 percent, respectively.

Pharmacological prophylaxis decreases the risk of DVT with some increased risk of minor bleeding when compared with no pharmacological prophylaxis.

LMWH may decrease the risk for DVT when compared with warfarin at the expense of increases in major and minor bleeding.

LMWH provides greater protection against DVT and PE when compared with unfractionated heparin while reducing the risk of bleeding and heparin-induced thrombocytopenia.

LMWH was not as effective in protecting against the risk of DVT when compared with an injectable factor Xa inhibitor, although the odds of bleeding were reduced.

Prolonged prophylaxis decreased the risk of thromboembolism at the risk of increased minor bleeding when compared with standard-duration prophylaxis.

Summary of Conclusions

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 28: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Inadequate data did not permit conclusions about the comparative benefits and adverse effects associated with VTE prophylaxis in non–joint–replacement surgery.

More information is needed on the following aspects of VTE prophylaxis in the setting of major orthopedic surgery: Clinically important outcomes including symptomatic venous

thromboembolism, post-thrombotic syndrome, clinically relevant bleeding, prosthetic infection, reoperation, and mortality and whether intermediate outcomes predict health outcomes

Surgical, postsurgical, or patient factors that predict outcomes The optimal followup period needed to determine longer term

outcomes Optimal duration of thromboprophylaxis The role of combined pharmacological and mechanical

prophylaxis

Gaps in Knowledge

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 29: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

General background information on the risk of thromboembolic disease

That thromboembolic disease is a major risk after joint–replacement surgery and why some form of prophylactic treatment is indicated

Options for prophylaxis Bleeding as the major risk of pharmacological

prophylaxis

What To Discuss With Your Patients

Sobieraj DM, Coleman CI, Tongbram V, et al. Comparative Effectiveness Review No. 49. Available at www.effectivehealthcare.ahrq.gov/thrombo.cfm.

Page 30: Venous Thromboembolism Prophylaxis in Orthopedic Surgery

Resource for Patients Preventing Blood Clots After

Hip or Knee Replacement Surgery or Surgery for a Broken Hip, A Review of the Research for Adults is a free resource for patients. It can help patients talk with their health care professionals about the many options for treatment. It provides information about: Pharmacological options for

preventing venous thromboembolism (VTE)

Nonpharmacological options for preventing VTE

Current evidence of effectiveness and harms associated with VTE-prevention methods

Questions for patients to ask their doctor