Dvt prophylaxis in total joint reconstruction

D V T P ro p h y l a x i si n Tot a l J o i n tR e c o n s t r u c t i o n Neil P. Sheth, Jay R. Lieberman, MDCraig J. Della Valle, MD  Prophylaxis  Deep venous thrombosis Venous thromboembolism  Total joint arthroplasty Deep venous thrombosis (DVT) is the end result of the earlier part of this decade. The surgical care a complex interaction of events including the acti- improvement project (SCIP) guidelines, a result vation of the clotting cascade in conjunction with of the consensus, require documentation of initia- platelet aggregation. It has been clearly demon- tion of DVT prophylaxis in the time period extend- strated that patients undergoing major lower ing from 24 hours before surgery to 24 hours extremity orthopedic surgery, especially total joint arthroplasty (TJA), are at high risk for developing a postoperative DVT or a subsequent pulmonary emphasis on pay-for-performance (P4P) whereby embolus (PE). In the arena of TJA, orthopedic physicians receive increased compensation as surgeons are particularly concerned with proximal a function of meeting certain ‘‘standards of Patients undergoing primary total hip arthro- Despite several years of evaluating this ques- plasty (THA) or total knee arthroplasty (TKA) have tion, the best prophylaxis for thromboembolic exhibited rates of symptomatic PE as high as disease remains controversial.The use of phar- 20% and 8%, respectively when no prophylaxis macologic prophylaxis has been adopted as the standard of care for treatment of these patients venous thromboembolic (DVT and PE) prophy- by many orthopedic surgeons at most centers laxis, most commonly pharmacologic prophylaxis, has become the standard of care for patients between the efficacy of VTE prophylaxis and the undergoing elective TJA. The risk of fatal PE increased risk for bleeding in the postoperative following primary hip or knee replacement has period continues to exist. In recent years, this been consistently reported to be between 0.1% debate has brought about the development of clin- and 0.2%, regardless of the chemoprophylactic ical guidelines to improve patient care, address key questions, define evidence-based recommen- Based on the necessity of postoperative venous dations, and promote future research. Clinical thromboembolic (VTE) prophylaxis following TJA, guidelines are not meant to represent a predefined the National Quality Forum endorsed a voluntary protocol or absolute rules for treatment, and consensus standard for inpatient hospital care in should never substitute for clinical judgment.
The authors have not received any financial support for the work and have no other financial or personalconnections to the work presented in this article.
a Department of Orthopaedic Surgery, Rush University, Midwest Orthopaedics, 1725 West Harrison Street,Chicago, IL 60612, USAb Department of Orthopaedic Surgery, New England Musculoskeletal Institute, Medical Arts and ResearchBuilding, University of Connecticut Health Center, 263 Farmington Avenue, Farmington, CT 06030-4038, USAc Department of Orthopaedic Surgery, Rush University, 1725 West Harrison Street, Chicago, IL 60612, USA* Corresponding author.
E-mail address: doi:10.1016/j.ocl.2010.02.0010030-5898/10/$ – see front matter ª 2010 Elsevier Inc. All rights reserved.
Dependent on the clinical guideline followed, from guidelines from 1998 and 2001 recommended 7 the American College of Chest Physicians (ACCP) or to 10 days of prophylaxis that coincided with the the American Academy of Orthopaedic Surgeons length of hospital stay (Grade IA recommenda- (AAOS), there are several recommended regimens tion).In 2004, the guidelines were revised to available for treatment. Included in the options are recommend out of hospital prophylaxis for 28 to low molecular weight heparins (LMWHs), synthetic 35 days (Grade IA) but excluded patients under- pentasaccharides, adjusted-dose warfarin, aspirin, going TKA.With additional revisions, the 2008 and mechanical prophylaxis. Several studies have evaluated the various modalities for DVT prophy- laxis, and comparison studies have stratified the warfarin for up to 10 days following THA and TKA (Grade IA), and up to 35 days following THA The following review addresses the controversy underlying VTE prophylaxis by outlining 2 guide- As with any guidelines being used to guide lines and demonstrating the pros and cons of physicians in medical decision making, the risk different DVT prophylaxis regimens based on the versus benefit must be assessed. Implementation available evidence-based literature.
of the current ACCP guidelines has been associ-ated with certain disadvantages, as reported in the orthopedic literature. Burnett and colleagues reported a 4.7% readmission rate, 3.4% irrigationand debridement rate, and 5.1% rate of prolonged The ACCP was founded in 1935, and the first set of hospitalization following 10 days of LMWH after guidelines for venous thromboembolic prophylaxis (VTE) was published in 1986. The goal of these patients with a wound hematoma or persistent guidelines is to focus on the prevention of the wound drainage are at higher risk for a postopera- overall rate of VTE. These guidelines are based tive deep joint infection. As a direct consequence on a review of prospective, randomized studies of the concerns for postoperative bleeding risk only. The guidelines have subsequently gone and potential for infection, orthopedic surgeons through several iterations with the most recent may prefer a more risk-averse method by which update in Inherent to these guidelines is to prevent thromboembolic phenomena following that all primary THA and TKA patients are consid- TJA, especially because the rate of PE is similar ered ‘‘high risk’’ regardless of patient age, activity regardless of the chemoprophylaxis agent used.
These guidelines have become commonplace in the evaluation of health care systems on behalf of hospitals, insurance companies, and attorneys.
The recommendations were classified as Grade I A work group from the AAOS in conjunction with the (strong recommendation, with benefits outweigh- Center for Clinical Evidence Synthesis (Tufts New ing risk, burden, and cost) or Grade II (recommen- England Medical Center) proposed a new set of guidelines for the prevention of symptomatic and recommendation was further substratified: (A) fatal PE in patients undergoing elective TJA. The AAOS guidelines are a synthesis of an expert results and a low level of bias, (B) randomized consensus as well as an analysis of 42 articles pub- controlled trials with inconsistent results or a major lished since 1996, and focus on the prevention of methodological design flaw, and (C) observational symptomatic PE. The clinical outcomes of choice studies.The use of LMWH, fondaparinux (penta- for evaluation included symptomatic and fatal PE, saccharide), and warfarin (with an adjusted inter- death, and major bleeding episodes following national normalized ratio [INR] between 2.0 and TJA.Consensus recommendations included the 3.0) all received a Grade IA recommendation for use of regional anesthesia, mechanical prophylaxis preventative treatment of total hip and knee ar- for all patients, rapid postoperative mobilization, throplasty; aspirin or low-dose unfractionated and adequate patient education. Each patient heparin received a Grade IA rating against their required a preoperative evaluation for a determina- use for prophylaxis in patients following TJA. The tion of ‘‘standard’’ and ‘‘high’’ risk potential. The choice of a specific chemoprophylaxis agent was devices received a Grade IB rating for prevention based on the individual risk-benefit profile for PE These guidelines also address the duration of prophylaxis. During the first iteration, the ACCP following system: (A) good evidence (level I studies DVT Prophylaxis in Total Joint Reconstruction with consistent findings) for recommending inter- a weakness inherent to the AAOS guidelines is vention, (B) fair evidence (level II or III studies the inability to accurately assess the preoperative with consistent findings) for recommending inter- risk for DVT/PE. In reality, based on the nature of vention, and (C) poor-quality evidence (level IV or TJA, arthroplasty patients may not truly be consid- ered low risk. In addition, there are studies to the total number of recommendations from this demonstrate rates of VTE as high as 72% following set of guidelines, only 4 of them were derived the administration of aspirin,thus raising the from a systematic review of the literature. Addi- question of whether the use of aspirin is adequate tional general consensus recommendations are For patients at standard risk for both PE and major bleeding complications, the recommenda-tion is as follows: aspirin, LMWH, pentasacchar- The use of LMWH has gained enthusiasm within the orthopedic community due to its well-docu- recommendation is based on level III evidence mented bioavailability and the absence of moni- toring for clotting indices (ie, INR). The efficacy of For patients at elevated risk for PE and standard LMWH is well documented. In multiple random- risk for major bleeding complications, the recom- ized trials, including THA and TKA patients, mendation is as follows: LMWH, pentasaccharide, LMWH has been more effective than warfarin in or warfarin (INR goal of %2.0). This recommenda- limiting overall DVT rates. However, LMWH is tion is based on level III evidence and was given associated with higher bleeding rates. Because the selection of a prophylaxis agent is a balance For patients with standard risk of PE and between efficacy and safety, some surgeons elevated risk of major bleeding complications, the recommendation is as follows: aspirin, warfarin concerns related to bleeding and its impact on (INR goal of %2.0), or none. This recommendation overall outcomes. An additional consideration is based on level III evidence and was given with any medication choice is the cost; the cost of LMWH remains relatively high as compared For patients with elevated risk of both PE and major bleeding complications, the recommenda- As with any postoperative chemoprophylaxis tion is as follows: aspirin, warfarin (INR goal of regimen, duration of treatment is always of concern.
%2.0), or none. This recommendation is based The ACCP guidelines have changed their recom- on level III evidence and was given a grade of C.
mendations since the initial guidelines introduced The most important concept that is fundamental in 1998. The most recent recommendation from to the AAOS guidelines for thromboembolic the ACCP in 2008 states that patients undergoing prophylaxis is that the risk versus benefit for THA or TKA should receive chemoprophylaxis each individual patient must be assessed in the with LMWH for 7 to 10 days (Grade IA recommenda- preoperative period. The general recommenda- tion), and this may be extended to up to 35 days following THA. Administration of LMWH for 35 work group’s consensus, and address a majority days following TKA received a Grade 2B recom- of the perioperative issues with prophylaxis. For mendatioAs stated previously, the choice of patients with elevated risks for PE, major bleeding agent as well as the duration of prophylaxis is based complication, or both, these guidelines provide an on a risk versus benefit analysis which should be effective manner by which to treat these patients in individualized for each arthroplasty patient.
the postoperative period following TJA. However, Fondaparinux is a newer synthetic pentasaccharide that is a potent inhibitor of Factor Xa in the clotting cascade. The typical dosing is 2.5 mg/dadministered subcutaneously with the first dose being given at 6 to 12 hours postoperatively. This drug is not recommended for patients that weigh less than 50 kg or those with renal insufficiency.
As with LMWH, the concern associated with the use of fondaparinux is for bleeding complicationsin the postoperative period.
Table 2Consensus recommendations from the AAOS work group Assess all patients preoperatively with regard to their risk Assess all patients preoperatively with regard to their risk (standard vs high) of bleeding complications Consider vena cava filter placement for patients who have a known contraindication to anticoagulation therapy Consider intraoperative or immediate postoperative Consider regional anesthesia for the procedure (in Consider use of mechanical prophylaxis postoperatively Routine screening for thromboembolism is not Educate the patient about symptoms of thromboembolism Data from Johanson NA, Lachiewicz PF, Lieberman JR, et al. Prevention of symptomatic pulmonary embolism in patientsundergoing total hip or knee arthroplasty. J Am Acad Orthop Surg 2009;17(3):183–96.
The use of fondaparinux received a Grade 1A concomitantly taken by a patient for other comor- bid conditions (). As a result, the goal INR is Regarding duration of treatment, the most recent A meta-analysis of all randomized controlled changes to the ACCP guidelines in 2008 support clinical trials reported on the overall efficacy of the use of the agent for 35 days after THA (Grade warfarin as a prophylactic agent following THA.
Patients treated with warfarin had the lowest rate concerns about using this drug in patients at an of proximal DVT as well as symptomatic PE, with increased rate of bleeding as seen in the AAOS a rate of 6.3% and 0.16%, respectively. The risk guidelines, but this is not an evidence-based of major postoperative bleeding in these patients was no higher than that in patients treated witha placebo.
The use of warfarin as an effective prophylactic agent following TKA has been thoroughly demon- Warfarin is the oldest vitamin K antagonist used for chemoprophylaxis, with the longest track recordof use in the postoperative period followingprimary hip or knee arthroplasty. The traditional nature of medicine has helped maintain warfarin as a popular agent, because it was the treatmentof choice when most orthopedic surgeons trained during residency. Warfarin has demonstrated effi- cacy as an effective chemoprophylaxis agent against thromboembolic disease; however, it is Quinolone antibiotics (ie, ciprofloxacin) not without its disadvantages. Immediately post administration, the patient is in a relatively hyper- coagulable state due to diminished levels ofprotein C and protein S via actions of the drug.
Each patient requires daily dosing and the blood is monitored daily for an INR level to determine the appropriate dose to administer. Warfarin is very sensitive to dietary changes and has interac- tions with several medications that may be DVT Prophylaxis in Total Joint Reconstruction randomized clinical trials have compared the effi- chemoprophylaxis be timed appropriately to mini- every study, LMWH was more effective than Aspirin functions by way of inhibiting platelet warfarin as a prophylactic agent, but there was aggregation, and if given immediately preopera- no significant difference in the rates of symptom- tively, can function in this manner intraoperatively atic proximal DVT or PE. The postoperative and in the immediate postoperative period; other bleeding rates were typically higher in the LMWH chemoprophylaxis agents exhibit a postoperative delay before the onset of the desired prophylaxis With regard to the goal INR, different clinical effect. The major benefit associated with aspirin guidelines present differing recommendations. Ac- use is its low prevalence of wound-healing prob- cording to the ACCP clinical guideline, a goal INR lems, hematoma formation, and other serious of 2.0 to 3.0 received a Grade 1A recommendation.
bleeding complications that are readily associated This recommendation was made based on random- with more potent anticoagulant agents.
ized trials that used an INR range of 2.0 to 3.0 as the In the arena of TKA, aspirin has been equally as target for prophylaxis.For each scenario depicted effective as other anticoagulant agents when fatal by the AAOS where the use of warfarin is warranted, PE is used as an end poinLotke and colleagu the goal INR is 2.0 or less. The difference in the goal reported on 2800 consecutive primary TKAs in INR is based on risk versus benefit between prophy- patients treated with aspirin and mechanical laxis against thromboembolic disease and bleeding prophylaxis, demonstrating a low rate of bleeding risk. The AAOS guidelines consistently make recom- complication and a fatal PE risk of 0.1%. However, mendations that are more conservative and attempt aspirin is not as effective in decreasing the risk of to minimize the postoperative bleeding risk and symptomatic DVT in the setting of THA. The Pulmo- nary Embolism Prevention trial was a randomized As with the use of LMWH, the ACCP guidelines clinical trial designed to evaluate the efficacy of have changed their recommendations regarding aspirin in preventing symptomatic VTE disease the duration of warfarin use following primary hip following THA. More than 4000 patients were or knee replacement. The 2008 ACCP guidelines randomized to receive aspirin (n 5 2047) or recommend up to 35 days of warfarin use (goal a placebo (n 5 2041) for 35 days following surgery.
INR 2.0–3.0) with a Grade 1B recommendation There was no statistical difference in the rate of for THA and a Grade 1C recommendation for symptomatic DVT between the 2 groups (P>.5).
TKA patients. The AAOS recommendation, for patients of standard risk for PE and bleeding, is 2 following primary hip and knee arthroplasty has to 6 weeks of treatment with low-dose warfarin decreased significantly over the past decade, (goal INR %2.0). Even in patients with an elevated mainly due to a multidisciplinary approach. Rapid PE and bleeding risk, low-dose warfarin is recom- postoperative mobilization, optimization of surgical management, including the use of regional anes- thesia, have all contributed to decreasing the DVTrisk. The ACCP guidelines do not support the use Acetylsalicylic acid (aspirin) has gained in popu- of aspirin for prophylaxis following TJA, because larity as an agent for DVT prophylaxis following this drug has not been extensively evaluated in total joint replacement because it is safe, inexpen- multicenter randomized trials. The AAOS guide- sive, does not require monitoring, is easy to lines support the use of aspirin for 6 weeks except administer, and lends itself to high patient compli- in patients that are at high risk for PE and have stan- ance. The recommended dosing in the postopera- dard bleeding complication risk; these patients are tive period is 325 mg twice daily for the duration of not candidates for aspirin use because of the iden- tified preoperative elevated risk for PE.
premise that chemoprophylaxis should be admin- Because the selection of a prophylaxis agent is istered to reduce the risk of PE and subsequent a balance between safety and efficacy, aspirin death, not DVT; inherent to this argument is that combined with mechanical devices is an attractive DVT should not be used as a surrogate for PE regimen for some orthopedic surgeons for their because all patients with a DVT do not inevitably routine TJA patients. Although aspirin is less potent than other chemoprophylactic agents, it is Aspirin does not interfere with anesthetic admin- also associated with less bleeding. Aspirin needs istration because it does not increase the risk of to be evaluated in large randomized trials that neuraxial bleeding. The use of an epidural catheter assess symptomatic events to determine its true for pain control requires that postoperative The basic difference between the ACCP and the The use of mechanical prophylaxis is predicated AAOS guidelines is that the chest physicians on the premise that decreasing lower extremity believe that asymptomatic clots are clinically rele- venous stasis in conjunction with increasing vant. Therefore, the ACCP guidelines were devel- venous blood flow will decrease the likelihood of oped from the data obtained from randomized trials, which used venogram data as a surrogate affect local fibrinolysis, but do not affect systemic outcome measure. In contrast, the AAOS guide- fibrinolytic Intermittent plantar compres- lines reflect the concerns of orthopedic surgeons sion devices were designed to replicate the hemo- with a focus on symptomatic clots, PE, and dynamic effects of normal walking by rapid bleeding risk. Furthermore, the AAOS guidelines emptying of the plantar arch during the compres- highlight the importance of developing prophylaxis sion phase of the device.The advantages of regimens for each individual patient based on PE mechanical prophylaxis are evident and include and bleeding risk. This is an important concept, an absence of monitoring and no risk of bleeding.
which moves us toward risk stratification. Unfortu- In addition, intermittent plantar compression nately, it is difficult to risk stratify most patients devices are thought to be less cumbersome than based on available data but it is a goal to strive pneumatic boots, which extend the length of the entire lower leg. However, the major disadvan- Surgeons need to be aware that the SCIP guide- tages are that prophylaxis ceases on patient lines recommend LMWH, fondaparinux, and/or discharge from the hospital, and patient compli- warfarin for THA and TKA patients. Pneumatic ance is critical to either device being effective.
compression devices are also acceptable for Several randomized clinical trials have demon- patients undergoing TKA procedures. Therefore, strated that pneumatic compression boots can aspirin and pneumatic compression devices are limit distal thrombus formation.As a result, acceptable for TKA patients. A surgeon may there has been concern regarding the efficacy of mechanical compression in reducing the rates of concerns about bleeding, but this must be docu- proximal clot formation in the setting of THA.
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