The effect of intraoperative intravenous fixed-dose heparin during total joint arthroplasty on the incidence of fatal pulmonary emboli

Femoral Stem Cementation in Hip Arthroplasty: The Know-How of a "Lost" Art

PURPOSE OF REVIEW

To describe the (1) indications, (2) preoperative precautions, and (3) stepwise technical details of modern femoral stem cemented fixation.

RECENT FINDINGS

Femoral stem cementation provides excellent implant longevity with a low periprosthetic fracture rate among patients with compromised bone quality or aberrant anatomy. Unfamiliarity with the details of modern cementation techniques among trainees who may lack frequent exposure to cementing femoral stems may preclude them from offering this viable option to suitable patients in later stages of their careers. As such, maximizing benefit from cemented femoral stem fixation among suitable candidates is contingent upon the meticulous use of modern cementation techniques. In addition to proper patient selection, modern cementation techniques emphasize the use of (1) pulsatile lavage of the femoral canal, (2) utilization of epinephrine-soaked swabs, (3) vacuum cement mixing, (4) retrograde cement introduction, (5) cement pressurization, and (6) the use of stem centralizers. Furthermore, identifying and optimizing the preoperative status of at-risk patients with pre-existing cardiopulmonary compromise, in addition to intraoperative vigilance, are essential for mitigating the risk of developing bone cement implantation syndrome. Further research is required to assess the utility of cemented femoral stem fixation among younger patients.

Twenty-Five-Years and Greater, Results After Nonmodular Cemented Total Knee Arthroplasty

BACKGROUND

Total knee arthroplasty (TKA) has been shown to be very successful with long-term follow-ups. But there are no reports showing prosthesis survival at 25-30 years. Here, we report the outcomes for 25-30 years using the Anatomic Graduated Component (Biomet, Warsaw, IN) TKA and elucidate the etiology and cause of failure of the components.

METHODS

We reviewed the outcomes of 5649 primary total knee arthroplasties for 25-30 years using the Anatomic Graduated Component. Statistical analysis was performed by the Kaplan-Meier survival analysis. Clinical outcomes included the Knee Society Score and standardized radiographs to check for loosening of the implants. The reason for revision surgery was reviewed retrospectively. We compared our results with those at another institution with similar long-term follow-up.

RESULTS

There were 112 failures, 48 with aseptic loosening and 25 with instability for an overall prosthesis survival rate of 94.2% at 25 years and 92.4% at 30 years follow-up. In the third decade after TKA, patients are substantially more likely to experience death than experience a failing prosthesis, with a 3811% greater risk of dying relative to failing (Risk ratio = 38.1, Odds ratio = 56.7, P < .0001).

CONCLUSION

There was a greater risk of dying than failing over time. The primary reason for revision knee surgery was due to aseptic loosening of the prosthesis followed by instability.

Less deep vein thrombosis due to transcutaneous fibular nerve stimulation in total knee arthroplasty: a randomized controlled trial

PURPOSE

It has been known for years that deep vein thrombi (DVT) start to develop during total joint arthroplasty. Previously, we reported effective prevention of venous stasis by transcutaneous electrical nerve stimulation (TENS). It is hypothesized that TENS might be a thromboprophylactic tool for the limb undergoing surgery. The purpose of this study is to clarify the clinical efficacy and safety of TENS in patients during total knee arthroplasty (TKA).

METHODS

Ninety patients undergoing primary TKA were involved and randomly allocated to the TENS or control group. In the TENS group, electrical stimulation of the common fibular nerve, which produced a brisk dorsiflexion of the ankle, was performed for the operated leg during surgery. In the control group, no electrical stimulation was applied. Serum D-dimer and soluble fibrin monomer complex (SFMC) levels were measured before surgery, immediately after surgery, and post-operative day (POD) 1. Ultrasonography was performed on POD 1.

RESULTS

Immediately after surgery, D-dimer and SFMC levels of each group were significantly lower in the TENS group compared with control (p < 0.05). The incidence of DVT was 11 % (five cases) in the TENS group while 31 % (14 cases) in control (p = 0.02). There were no adverse effects related to TENS.

CONCLUSIONS

TENS during TKA showed significant effects on preventing DVT. Sustaining muscle pump activation during surgery prevented not only venous stasis, but also hypercoagulability of blood. Intraoperative TENS is a safe and novel strategy against early post-operative thromboembolism, which is difficult to be completed through existing prophylaxis after total joint arthroplasty.

LEVEL OF EVIDENCE

Randomized controlled trial, Level I.

Meta-analysis of cause of death following total joint replacement using different thromboprophylaxis regimens

We performed a meta-analysis of modern total joint replacement (TJR) to determine the post-operative mortality and the cause of death using different thromboprophylactic regimens as follows: 1) no routine chemothromboprophylaxis (NRC); 2) Potent anticoagulation (PA) (unfractionated or low-molecular-weight heparin, ximelagatran, fondaparinux or rivaroxaban); 3) Potent anticoagulation combined (PAC) with regional anaesthesia and/or pneumatic compression devices (PCDs); 4) Warfarin (W); 5) Warfarin combined (WAC) with regional anaesthesia and/or PCD; and 6) Multimodal (MM) prophylaxis, including regional anaesthesia, PCDs and aspirin in low-risk patients. Cause of death was classified as autopsy proven, clinically certain or unknown. Deaths were grouped into cardiopulmonary excluding pulmonary embolism (PE), PE, bleeding-related, gastrointestinal, central nervous system, and others (miscellaneous). Meta-analysis based on fixed effects or random effects models was used for pooling incidence data. In all, 70 studies were included (99 441 patients; 373 deaths). The mortality was lowest in the MM (0.2%) and WC (0.2%) groups. The most frequent cause of death was cardiopulmonary (47.9%), followed by PE (25.4%) and bleeding (8.9%). The proportion of deaths due to PE was not significantly affected by the thromboprophylaxis regimen (PA, 35.5%; PAC, 28%; MM, 23.2%; and NRC, 16.3%). Fatal bleeding was higher in groups relying on the use of anticoagulation (W, 33.8%; PA, 9.4%; PAC, 10.8%) but the differences were not statistically significant. Our study demonstrated that the routine use of PA does not reduce the overall mortality or the proportion of deaths due to PE.

DVT prophylaxis in total joint reconstruction

Deep venous thrombosis (DVT) is the end result of a complex interaction of events including the activation of the clotting cascade in conjunction with platelet aggregation. Patients undergoing major lower extremity orthopedic surgery, especially total joint arthroplasty (TJA), are at high risk for developing a postoperative DVT or a subsequent pulmonary embolus. Venous thromboembolic (VTE) prophylaxis, most commonly pharmacologic prophylaxis, has become the standard of care for patients undergoing elective TJA. However, the controversy between the efficacy of VTE prophylaxis and the increased risk for bleeding in the postoperative period continues to exist. This review addresses the controversy underlying VTE prophylaxis by outlining 2 guidelines and demonstrating the pros and cons of different DVT prophylaxis regimens based on the available evidence-based literature.

Effect of periarticular corticosteroid injections during total knee arthroplasty. A double-blind randomized trial

BACKGROUND

Multimodal pain-control protocols that include periarticular injections have been reported to decrease pain and improve early outcomes following total knee arthroplasty. While injections containing a corticosteroid have been demonstrated to be safe and effective, we are not aware of any randomized trials in which the specific effect of the corticosteroid on early postoperative outcomes has been evaluated. The purpose of this double-blind study was to compare the clinical efficacy of periarticular injections consisting of bupivacaine, morphine, epinephrine, clonidine, and cefuroxime as well as a corticosteroid (methylprednisolone acetate) with the efficacy of periarticular injections consisting of the same agents but without the inclusion of a corticosteroid.

METHODS

Seventy-six patients were randomized to either the no-steroid group (thirty-seven patients) or the steroid group (thirty-nine patients). Pain and narcotic consumption during the inpatient stay and the length of the hospital stay were recorded. Knee Society scores, the range of motion, and the occurrence of any complications were recorded preoperatively and at six and twelve weeks after the surgery.

RESULTS

The hospital stay was significantly shorter for patients in the steroid group (2.6 days compared with 3.5 days in the no-steroid group; p = 0.01). No significant group differences in terms of pain, narcotic consumption, outcome scores, or motion were identified. There were three complications in the steroid group: two patients required a manipulation under anesthesia, and the knee joint became infected in another patient, leading to numerous complications and ultimately death.

CONCLUSIONS

The periarticular injection of a corticosteroid may reduce the length of the hospital stay following total knee arthroplasty, but it does not appear to improve pain relief, motion, or function in the early postoperative period. While we cannot definitively state that the corticosteroid was a causative factor in the development of the infection at the site of the prosthetic joint, we cannot rule it out either, which raises concern regarding the role of corticosteroids in perioperative pain management following total knee arthroplasty.

The Anatomical Graduated Component total knee replacement: a long-term evaluation with 20-year survival analysis

The long-term success of total knee replacement is multifactorial, including factors relating to the patient, the operation and the implant. The purpose of this study was to examine the 20-year survival of the cemented Anatomical Graduated Component (AGC) total knee replacement. Between 1983 and 2004, 7760 of these were carried out at our institution. Of these, 6726 knees which received the non-modular metal-backed tibial component with compression-moulded polyethylene and had a minimum two-year follow-up were available for study. In all, 36 knees were followed over 20 years with a survival of the tibial and femoral components together of 97.8% (95% confidence interval (CI) 0.9851 to 0.9677), with no implants being revised for polyethylene wear or osteolysis. Age > 70 was associated with increased survival (99.6%, 95% CI 99.0 to 99.8) (p < 0.0001) but pre-operative valgus alignment reduced survival (95.1%, 95% CI 90.0 to 97.6) (p = 0.0056). Age < 55 (p = 0.129), pre-operative varus alignment (p = 0.707), osteonecrosis (p = 0.06), rheumatoid arthritis (p = 0.247), and gender (p = 0.666) were not statistically associated with failure. We attribute the success of the AGC implant to its relatively unconstrained articular geometry and the durability of a non-modular metal-backed tibial component with compression moulded polyethylene.

Changes of D-dimer after total hip arthroplasty in patients with and without intraoperative heparin

INTRODUCTION

Marked activation of thrombosis is common in patients undergoing total hip arthroplasty, especially during reaming of the femur and after insertion of the femoral prosthesis. This suggests that management designed to minimize deep vein thrombosis and fatal pulmonary embolism after total hip arthroplasty should be focused on the period during insertion of the femoral component. In some previous studies, a low dose of heparin administered intraoperatively was shown to suppress the formation of fibrin.

OBJECTIVE

The present study was performed to evaluate the influence of intraoperative heparin administration on the D-dimer level and on the prevention of pulmonary embolism after total hip arthroplasty.

MATERIAL/METHODS

A total of 22 and 26 consecutive patients respectively underwent total hip arthroplasty with and without intraoperative administration of unfractionated heparin. Postoperatively, all patients wore knee-high elastic stockings and were fitted with calf-to-thigh intermittent pneumatic compression devices. Active ankle flexion and extension exercises were commenced as soon as motor function recovered. None of the 48 patients received prophylactic anticoagulants postoperatively.

RESULTS

There was a significant difference of the mean D-dimer level on the 1st day between the patients with and without intraoperative administration of heparin (8.9 +/- 6.6 vs. 15.7 +/- 12.7, P < 0.05). Although there were no patients with symptomatic deep venous thrombosis and pulmonary embolism, asymptomatic pulmonary embolism was detected by pulmonary perfusion scintigraphy in three patients who did not receive intraoperative heparin. The operative blood loss and postoperative drainage were similar in both groups and no bleeding complications were observed. In conclusion, we recommend a safe and inexpensive regimen comprising 1,000 U of intravenous unfractionated heparin intraoperatively, postoperative pneumatic compression, and early active mobilization for prevention of thoromboembolic complications after total hip arthroplasty.

Thromboembolic disease after total hip arthroplasty: who is at risk?

The strong activation of the clotting cascade that occurs during total hip arthroplasty places patients at increased risk for venous thromboembolism. The risk is higher in those patients with the following predisposing factors, listed in approximate order of importance: hip fracture; malignancy, particularly if associated with chemotherapy; antiphospholipid syndrome; immobility; history of venous thromboemholism; administration of tamoxifen; raloxifene; oral contraceptives or estrogen; morbid obesity; stroke; atherosclerosis; and an American Society of Anesthesiologists physical status classification of 3 or greater. The following risk factors are weak or controversial: advanced age; diabetes mellitus; congestive heart disease; atrial fibrillation; varicose veins; and smoking. However, 50% of patients who develop thromboembolism after total hip arthroplasty have no clinical predisposing factors. In a matched, controlled study, we defined the major genetic predispositions that increase the risk of venous thromboembolism after total hip arthroplasty: deficiency of antithrombin III (< 75%) and protein C (< 70%), and prothrombin gene mutation. Preoperative genetic screening in conjunction with the recognized clinical risk factors can help categorize postoperative venous thromboembolism risk and differentiate patients who can be protected with milder and safer prophylaxis (eg, aspirin, intermittent pneumatic compression) compared with those at higher risk who need to be anticoagulated.

The benefit of aspirin chemoprophylaxis for thromboembolism after total knee arthroplasty

The threat of thromboembolic events after total knee arthroplasty has been substantially reduced during the past decade. Currently, the risk of fatal pulmonary embolism is approximately 0.1%. This is due to a confluence of changes in our medical practices, including early mobilization, less traumatic surgery, increased use of regional anesthesia, pneumatic compression devices, and chemoprophylactic agents. Because many chemoprophylactic agents are associated with an increased risk of bleeding, we have chosen aspirin as our preferred method of chemoprophylaxis. This study seeks to determine if aspirin is as effective as newer chemoprophylactic agents as judged by the prevalence of fatal or nonfatal pulmonary embolus, readmission for deep venous thrombosis, and risk of bleeding. Aspirin was the principle chemoprophylactic agent for 3473 consecutive patients having total knee arthroplasty. All patients were followed for a minimum of 6 weeks. There were nine deaths: two from pulmonary embolism, five cardiac events, one stroke, and one fat embolism. Three cardiac-related deaths occurred in patients for whom pulmonary embolism could not definitively be ruled out. Therefore, the best case and worst case scenarios for fatal pulmonary embolism were 0.06% and 0.14%, respectively. Thirteen patients underwent reoperation for hematoma (0.4%). Therefore, we have demonstrated aspirin combined with early mobilization, regional anesthesia, foot pumps, and improved surgical techniques is safer than and equally efficacious as other chemoprophylaxis agents.

Venous thromboembolism is rare with a multimodal prophylaxis protocol after total hip arthroplasty

We evaluated the safety and efficacy of a multimodal approach for prophylaxis of thromboembolism after total hip arthroplasty, which includes preoperative discontinuation of procoagulant medication; autologous blood donation; hypotensive epidural anesthesia; intravenous administration of heparin during surgery and before femoral preparation; aspiration of intramedullary contents; pneumatic compression; knee-high elastic stockings; and early mobilization and chemoprophylaxis for 4 to 6 weeks (aspirin 83%; warfarin 17%). One thousand nine hundred forty-seven consecutive, nonselected patients (2032 total hip arthroplasties) who received this multimodal prophylaxis were observed prospectively for 3 months. The incidence of asymptomatic deep vein thrombosis assessed by ultrasound in the first 171 patients was 6.4%. The incidence of clinical deep vein thrombosis in the subsequent 1776 patients was 2.5%. Symptomatic pulmonary embolism occurred in 0.6% (12 of 1947; nine in patients receiving aspirin and three in patients receiving Coumadin), none of them fatal. One patient died of a myocardial infarct. This multimodal approach is safe and efficacious and compares favorably with those reported in the literature and with our historic controls. If these preventive measures are strictly observed during the perioperative period, postoperative chemoprophylaxis does not need to be aggressive in the patient without predisposing factors. Our low rate of deep vein thrombosis and pulmonary embolism do not support routine anticoagulation prophylaxis with drugs that increase risk of bleeding.

LEVEL OF EVIDENCE

Therapeutic study, Level IV (case series). See the Guidelines for Authors for a complete description of levels of evidence.

Deep venous thrombosis prophylaxis: better living through chemistry--in opposition

The best prophylactic regimens for thromboembolic disease continue to be debated despite years of investigation. The surgeon must balance the clinical risks and benefits. A decision depends on accurate data and our ability to balance the risks of fatal pulmonary embolism (PE) to the risk of bleeding. The current risk for fatal PE is 0.1% with most current prophylactic regimes. The risk of perioperative bleeding increases 1.8% to 5.2% with low molecular weight heparins or warfarin and generally is dose dependent. Most of the current prophylactic recommendations are based on the presence or absence of deep venous thrombosis (DVT). However, the correlation between the presence of a DVT and the risk of PE is low and inconsistent. Therefore, DVT may not be an accurate surrogate marker for the patient at risk after total joint surgery. Our experience with 2800 consecutive total knee arthroplasty patients, using aspirin as our principle agent, shows a fatal PE risk of 0.1% and a low risk of bleeding. Therefore, our current recommendation is aspirin.

Fat embolism in revision total hip arthroplasty

Two patients developed fat embolism syndrome after revision of loose total hip arthroplasties (THAs). During both procedures, the prosthesis became rigidly fixed 1 to 1.5 cm before the expected level of fixation. After uncomplicated operative courses, Patient A remained obtunded and febrile for 2.5 days, and Patient B died 1 day postoperatively. In Patient A, a presumptive diagnosis of fat embolism syndrome was based on the postoperative course and a radiograph of the lungs. In Patient B, the diagnosis was confirmed by evidence of cerebral edema on a computed tomography scan of the head. Fat embolism syndrome is unexpected after revision THA because the fatty tissue is removed from the femoral canal during primary THA. In these 2 cases, the rigid fixation and multiple attempts to impact and subsequently to remove the prosthesis may have caused fat embolism syndrome.

The relationship between pneumatic tourniquet time and the amount of pulmonary emboli in patients undergoing knee arthroscopic surgeries

Near-fatal pulmonary embolism can occur immediately after tourniquet release after orthopedic surgeries. In this study, we determined the relationship between tourniquet time and the occurrence of pulmonary emboli in 30 patients undergoing arthroscopic knee surgeries, by using transesophageal echocardiography. The right atrium (RA) was continuously monitored by transesophageal echocardiography, and the number of emboli present was assessed with the following formula: Amount of emboli = 100 x [(total embolic area in the RA after tourniquet release) - (total area of emboli or artifact in the RA before tourniquet release)]/(RA area). The area was assessed 0-300 s after tourniquet release by using image-analysis software. The peak amount of emboli appeared approximately 50 s after tourniquet release. In addition, there was a significant correlation between amount of emboli (Ae [%]) and tourniquet time (Ttq [min]): (Ae = 0.1 x Ttq - 1.0, r = 0.795, P < 0.01). This study suggests that acute pulmonary embolism may occur within 1 min of tourniquet release and that the number of emboli is dependent on Ttq.

The arterial tourniquet: pathophysiological consequences and anaesthetic implications

The arterial tourniquet is widely used in upper and lower extremity surgery and in intravenous regional anaesthesia. The local and systemic physiological effects and the anaesthetic implications are reviewed. Localised complications result from either tissue compression beneath the cuff or tissue ischaemia distal to the tourniquet. Systemic effects are related to the inflation or deflation of the tourniquet. Safe working guidelines for the application of an arterial tourniquet have not been clearly defined.

The safety and efficacy of intraoperative heparin in total hip arthroplasty

A single dose of unfractionated heparin (15 U/kg), administered intravenously before surgery on the femur suppresses thrombogenesis during total hip replacement. Nine hundred eighty-nine patients (1021 hips) who received one dose of intraoperative heparin with hypotensive epidural anesthesia were followed up prospectively for 3 months. Asymptomatic deep vein thrombosis assessed by ultrasound in the first 198 consecutive patients showed an incidence of 7.1% (14 of 198). The incidence of clinical deep vein thrombosis in the subsequent 791 patients was 0.88% (seven of 791). Symptomatic pulmonary embolism occurred in 0.5% (five of 989). No patients died and there was one major bleeding episode. Based on this favorable experience, intraoperative heparin appears safe and efficacious as thromboembolic prophylaxis.