Is duplex venous surveillance worthwhile after arthroplasty?

Same-day bilateral total knee replacement versus unilateral total knee replacement: A comparative study

INTRODUCTION

Bilateral total knee arthroplasty (TKA) in a single session is rarely done in France, mainly due to the increased risk of perioperative and late complications. The primary objective of this study was to compare the complication rates of same-day bilateral TKA (TKA bilat) with that of unilateral TKA (TKA unilat). The hypothesis was bilateral TKA increases the rate of early and late complications in a group of selected patients (ASA 1 or 2, less than 80 years of age).

MATERIAL AND METHODS

Retrospective comparative study of 91 bilat TKA and 182 unilat TKA cases operated on between 2009 and 2016 (1 bilat TKA paired with 2 controls). The patients were matched based on age, sex, indication and ASA score. The minimum follow-up was 2 years. Mortality along with early and late complications were documented. The secondary endpoints were implant survival, functional outcomes, and patient satisfaction.

RESULTS

The early mortality rate was zero in both groups. The early complication rate was lower in the bilat TKA group (9%) than in the unilat TKA group (22%) (p<0.001). The late complications did not differ between groups. Implant survival at 5 years was 99% (95% CI=[95.6-99.7]) in the bilat TKA group and 97% (95% CI=[92.8-98.8]) in the unilat TKA group. The autologous blood transfusion rate was 33% in the bilat TKA group and 2.2% in the unilat TKA group (p<0.001). There was no difference between groups in the satisfaction rate or the KOOS and New IKS scores. A larger share of patients in the unilat TKA group (54%) said they had forgotten about their knee than in the bilat TKA group (43%) (p=0.036).

DISCUSSION

There were few early complications in the bilat TKA group. There was no significant difference in the number of late complications, survival, functional scores, or patient satisfaction between the two groups. The transfusion rate was higher in the bilat TKA group, while the forgotten knee rate was higher in the unilat TKA group.

CONCLUSION

Our hypothesis was not confirmed: in the context of this study, in patients who are ASA 1 or 2, and less than 80 years old, same-day bilateral TKA does not increase the complication rate relative to unilateral TKA.

LEVEL OF EVIDENCE

III, comparative study of continuous paired cases.

Prophylactic anticoagulation to prevent venous thromboembolism in traumatic intracranial hemorrhage: a decision analysis

Introduction

Patients with intracranial hemorrhage due to traumatic brain injury are at high risk of developing venous thromboembolism including deep vein thrombosis (DVT) and pulmonary embolism (PE). Thus, there is a trade-off between the risks of progression of intracranial hemorrhage (ICH) versus reduction of DVT/PE with the use of prophylactic anticoagulation. Using decision analysis modeling techniques, we developed a model for examining this trade-off for trauma patients with documented ICH.

Methods

The decision node involved the choice to administer or to withhold low molecular weight heparin (LMWH) anticoagulation prophylaxis at 24 hours. Advantages of withholding therapy were decreased risk of ICH progression (death, disabling neurologic deficit, non-disabling neurologic deficit), and decreased risk of systemic bleeding complications (death, massive bleed). The associated disadvantage was greater risk of developing DVT/PE or death. Probabilities for each outcome were derived from natural history studies and randomized controlled trials when available. Utilities were obtained from accepted databases and previous studies.

Results

The expected value associated with withholding anticoagulation prophylaxis was similar (0.90) to that associated with the LMWH strategy (0.89). Only two threshold values were encountered in one-way sensitivity analyses. If the effectiveness of LMWH at preventing DVT exceeded 80% (range from literature 33% to 82%) our model favoured this therapy. Similarly, our model favoured use of LMWH if this therapy increased the risk of ICH progression by no more than 5% above the baseline risk.

Conclusions

Our model showed no clear advantage to providing or withholding anticoagulant prophylaxis for DVT/PE prevention at 24 hours after traumatic brain injury associated with ICH. Therefore randomized controlled trials are justifiable and needed to guide clinicians.

Deep vein thrombosis after total hip arthroplasty in Korean patients and D-dimer as a screening tool

INTRODUCTION

This prospective study was designed to confirm risk factors and to assess the incidence of deep vein thrombosis after total hip and surface replacement arthroplasty in Korean patients not receiving anticoagulation prophylaxis and to determine efficacy of plasma D-dimer levels as a screening test.

MATERIALS AND METHODS

From May 2003 to August 2004, 221 consecutive patients undergoing unilateral total hip arthroplasty and hip resurfacing were evaluated. All patients underwent ultrasonography preoperatively and venography and/or ultrasonography on postoperative day 7. Plasma D-dimer levels were estimated by latex immuno-assay preoperatively and on days 3 and 7 postoperatively.

RESULTS

Of the 221 patients in our cohort, 23 developed deep vein thrombosis (10.4%). Age (r = 0.245, P < 0.001) and gender (r = 0.155, P = 0.021) significantly correlated with deep vein thrombosis. Rise in incidence paralleled increase in age (X(2) = 32.860, P < 0.001). D-dimer levels on postoperative days 3 (gamma = 0.364, P < 0.001) and 7 (gamma = 0.470, P < 0.001) were significantly correlated to the development of DVT.

CONCLUSION

While incidence of deep vein thrombosis in Korean population after THA was lower than that in the West; it increased with age, and in female gender. Significant correlation was found between D-dimer levels and the development of deep vein thrombosis.

Prospective decision analysis for peripheral vascular disease predicts future quality of life

OBJECTIVE

Decision making for peripheral vascular disease can be quite complex as a result of pre-existing compromise of patient functional status, anatomic considerations, uncertainty of favorable outcome, medical comorbidities, and limitations in life expectancy. The ability of prospective decision-analysis models to predict individual quality of life in patients with lower extremity arterial occlusive disease was tested.

METHODS

This was a prospective cohort study. The settings were university and Veterans Administration vascular surgery practices. All 214 patients referred with symptomatic lower extremity arterial disease of any severity over a 2-year period were screened, and 206 were enrolled. A Markov model was compared with standard clinical decision-making. Utility assessment and generalized (Short Form-36; SF-36) and disease-specific (Walking Impairment Questionnaire; WIQ) quality of life were derived before treatment. Estimates of treatment outcome probabilities and intended and actual treatment plans were provided by attending vascular surgeons. The main outcome measures were generalized (SF-36) and disease-specific (WIQ) variables at study entry and at 4 and 12 months.

RESULTS

Primary intervention consisted of amputation for 9, bypass for 42, angioplasty for 8, and medical treatment for 147 patients. Considering all patients, no improvement in mean overall patient quality of life measured by the SF-36 Physical Component Score (27 +/- 8 vs 28 +/- 8; P = .87) or WIQ (39 +/- 22 vs 39 +/- 23; P = .13) was noted 12 months after counseling and treatment by the vascular surgeons. Individually considered SF-36 categories were improved only for Bodily Pain (40 +/- 23 vs 49 +/- 25; P = .03), with the most significant improvement observed among patients with the most severe pain (68 +/- 25 vs 37 +/- 23; P = .02) and among those undergoing bypass (60 +/- 29 vs 31 +/- 22; P = .02). It is noteworthy that when the treatment chosen was incongruent with the Markov model, patients were more likely to report a poorer quality of life at 1 year (Physical Component Score, 25 +/- 8 vs 29 +/- 8; P < .001). The quality of life predicted at baseline by the Markov model correlated positively with the Physical Component Score (r = 0.23), Bodily Pain (r = 0.33), and Fatigue (r = 0.44) and negatively with WIQ (r = -0.08) observed 1 year later.

CONCLUSIONS

Prospective application of an individualized decision Markov model in patients with vascular disease was predictive of patient quality of life at 1 year. The patient's outcome was worse when the treatment received did not follow the model's recommendation. This decision analysis model may be useful to identify patients at risk for poor outcomes with standard clinical decision making.

Routine duplex ultrasound screening after TKA is not necessary

We determined if negative ultrasound screening at the time of acute care hospital discharge or 2 weeks post operatively would reliably identify patients without deep venous thrombosis, thus allowing discontinuation of warfarin chemoprophylaxis. Patients undergoing primary TKA (1344) were treated with adjusted-dose warfarin (target prothrombin time, 15-18 seconds; internationalized normalization ratio, 1.4-1.7) until screening and then aspirin (325 mg po bid) until 6 weeks postoperatively. Deep venous thrombosis as determined by ultrasound was the measured outcome. From 1994 to 1997, 525 patients underwent screening ultrasound before discharge (usually postoperative Day 3): 12 (2.3%) patients with proximal deep venous thrombosis and three (0.6%) patients with distal deep venous thrombosis were identified. From 1997 to 2001, 819 patients underwent ultrasound screening at Day 14 postoperatively: 10 (1.2%) patients with proximal deep venous thrombosis and 29 (3.6%) patients with distal deep venous thromboses were identified. There was no difference in proximal deep venous thrombosis detection, but there was a difference in distal deep venous thrombosis detection. We no longer screen asymptomatic patients with ultrasound for deep venous thrombosis after TKA.

Incidence and risk factors for development of venous thromboembolism in Indian patients undergoing major orthopaedic surgery: results of a prospective study

INTRODUCTION

The incidence of venous thromboembolism (VTE) in Western populations undergoing major orthopaedic surgery without any thromboprophylaxis has been reported to range from 32% to 88%. There is however limited information on incidence of VTE in Indian patients and most of the Indian patients undergoing these surgeries do not receive any form of prophylaxis regardless of their risk profile.

METHODS

A prospective study was performed on 147 patients undergoing major orthopaedic surgery for total knee replacement (TKR), total hip replacement (THR), and proximal femur fracture fixation (PFF) without any prophylaxis. These patients were profiled for presence of the known risk factors responsible for development of VTE. A duplex ultrasound on both lower limbs was done 6 to 10 days after surgery. Twenty three patients underwent THR, 22 patients underwent TKR, and 102 underwent surgery for PFF. The patients were assessed clinically for any signs of deep venous thrombosis (DVT) and pulmonary embolism (PE). A helical CT scan was done in case of suspicion of PE and a duplex ultrasound was done in case of clinical suspicion of DVT irrespective of the stage of study.

RESULTS

The overall incidence of VTE was 6.12% and that of PE was 0.6%. The risk factors that were found to be significantly responsible for development of VTE (p < 0.05) were: immobility greater than 72 hours, malignancy, obesity, surgery lasting more than two hours.

CONCLUSION

The study reconfirms the belief that DVT has a lower incidence in Indian patients as compared with other ethnic groups.

Evaluation of Breast Cancer Risk Assessment Techniques: A Cost-effectiveness Analysis

Objective: Assess the effectiveness and cost-effectiveness of using biomarkers and risk assessment tools to stratify women for breast cancer preventive interventions.

Methods: A Markov model was developed to compare risk management strategies for high-risk women considering chemoprevention. Annual screening is compared to the use of chemoprevention for all women and the use of risk assessment technologies to stratify patients for chemoprevention. The biomarker atypia was used to stratify women by risk. Random fine-needle aspiration (rFNA) and ductal lavage (DL) were evaluated and compared as the risk assessment tools used to discover atypia. Sensitivity analyses explore assumptions regarding the prognostic and predictive characteristics of atypia, both the relative breast cancer risk and benefit from chemoprevention women with atypia incur.

Results: Risk assessment strategies using rFNA or DL in combination with chemoprevention are found to be cost-effective (&lt;$50,000 per life year saved) in high-risk groups under most scenarios. Both strategies were more effective and less costly in younger cohorts. Effectiveness of the risk assessment strategies increased when higher risk and increased benefit from chemoprevention were associated with atypia. Within the scenarios tested, rFNA is less costly than DL.

Conclusion: rFNA and DL appear to be cost-effective in high-risk women, assuming women with detected atypia choose tamoxifen. The tools are largely effective for women who are not motivated to take tamoxifen but would be if atypia were found. As biomarker risk assessment tools better predict the risk of breast cancer and or benefit of interventions, their cost-effectiveness increases.

Prospective decision analysis modeling indicates that clinical decisions in vascular surgery often fail to maximize patient expected utility

BACKGROUND

Applied prospectively to patients with peripheral arterial disease, individualized decision analysis has the potential to improve the surgeon's ability to optimize patient outcome.

METHODS

A prospective, randomized trial comparing Markov surgical decision analysis to standard decision-making was performed in 206 patients with symptomatic lower extremity arterial disease. Utility assessment and quality of life were determined from individual patients prior to treatment. Vascular surgeons provided estimates of probability of treatment outcome, intended and actual treatment plans, and assessment of comfort with the decision (PDPI). Treatment plans and PDPI evaluations were repeated after each surgeon was made aware of model predictions for half of the patients in a randomized manner.

RESULTS

Optimal treatments predicted by decision analysis differed significantly from the surgeon's initial plan and consisted of bypass for 30 versus 29%, respectively, angioplasty for 28 versus 11%, amputation for 31 versus 6%, and medical management for 34 versus 54% (agreement 50%, kappa 0.28). Surgeon awareness of the decision model results did not alter the verbalized final plan, but did trend toward less frequent use of bypass. Patients for whom the model agreed with the surgeon's initial plan were less likely to undergo bypass (13 versus 30%, P < 0.01). Greater surgeon comfort was present when the initial plan and model agreed (PDPI score 47.5 versus 45.6, P < 0.005).

CONCLUSIONS

Individualized application of a decision model to patients with peripheral arterial disease suggests that arterial bypass is frequently recommended even when it may not maximize patient expected utility.

Economic evaluation in total hip arthroplasty: analysis and review of the literature

We performed a bibliographic search of MEDLINE databases from January 1966 to July 2002 to identify English language articles that contained either "cost" or "economic" in combination with "total hip arthroplasty" (THA) in the abstract or title. Each study was then critically reviewed for content, technique, and adherence to established healthcare economic principles. Only 81 of the 153 studies retrieved contained actual economic data. Only 6% of studies adhered to established criteria for a comprehensive health care economic analysis. Although the number of publications regarding economic evaluation of THA is on the rise, the methodologic quality of many of these studies remains inadequate. Future studies should employ sound healthcare economic techniques to properly evaluate and assess the true social and economic value of THA.

Duplex ultrasonography after total hip or knee arthroplasty

We prospectively studied all patients admitted for total hip (THR) or knee (TKR) arthroplasty from July 2000 to February 2001. No pharmacological anticoagulation was given. All patients received a standardized postoperative rehabilitation regimen. Forty-six patients with known risk factors for deep vein thrombosis (DVT) were excluded. Eighty patients were studied (22 THR, 58 TKR; 55 women, 25 men). Mean age was 68 (30-90) years. Duplex ultrasonography on both lower limbs was performed on days 5-7 postoperatively. Location and extent of any thrombus were documented. In patients with distal DVT, a follow-up scan was done on days 10-14. If proximal propagation was observed, patients received full anticoagulation. If no propagation was detected, the distal thrombus was considered stable and clinical observation was continued. In the THR group, 1/22 and in the TKR group 9/58 were found to have distal DVT. All were asymptomatic. On follow-up scanning, none showed proximal propagation. All patients were followed up for at least 18 months, and none showed postthrombotic symptoms. Isolated distal DVT in "low-risk" Chinese patients after THR or TKR is not uncommon. Clinically they are usually "silent." If routine perioperative pharmacologic antithrombotic prophylaxis is not practiced, monitoring with duplex ultrasonography may need to be considered.

Deep venous thrombosis after total hip or knee arthroplasty in a "low-risk" Chinese population

Scarcely any information has been published on deep vein thrombosis (DVT) in Chinese patients after total hip arthroplasty (THA) or total knee arthroplasty (TKA). However, generally, no prophylaxis is given to patients who do not have conventional high-risk factors because they are believed to be at "low risk." We performed a prospective study on 80 such "low risk" patients undergoing THA or TKA (58 TKA and 22 THA) without prophylaxis and performed duplex ultrasonography on both lower limbs 6 to 8 days after surgery. A total of 22 patients (27.5%) showed ultrasonographic evidence of DVT. Eighteen (31%) TKAs and 4 (18.1%) THAs were complicated by DVT. Three patients showed bilateral involvement, all of whom underwent TKA. Two patients had symptomatic pulmonary embolism. The sensitivity and positive predictive value of the clinical examination was 27.2% and 31.6%, respectively. This study showed that patients who are labeled "low risk" for DVT actually had a significant risk and suggests that the current practice of providing prophylaxis to only patients deemed at "high risk" should be revised.

Thromboprophylaxis and Total Hip Replacement: A Cost-Efficacy Study Comparing Duplex Screening of Asymptomatic Venous Thrombosis versus Prolonged Prophylaxis with Low-Molecular-Weight Heparins

Background:

Despite use of the anti-thrombotic prophylaxis, clinical thrombo-embolic events and fatal pulmonary embolism are still observed after total hip replacement. To reduce these complications, two strategies have been adopted: to prolong the use of low-molecular-weight heparins (LMWH) to 35 days or to screen patients systematically before discharge, using duplex ultrasonography, following the short-course prophylactic treatment.

Objective:

To assess, based on published literature, the relative costs and benefits of these two strategies for prophylaxis following total hip arthroplasty.

Method:

The author identified relevant papers in this field from his own resources and from medical literature databases.

Synthesis:

Prolonging LMWH treatment to a total of 35 days represents a direct cost in France of approximately £340 per patient, or for 100000 total hip replacements per year, an annual budget of £34 000000. If this strategy attained maximum efficacy, it would avoid 150 fatal pulmonary embolisms. The direct cost would therefore be at least £227000 per life saved. A systematic single duplex ultrasound examination before discharge from hospital would cost £76 per patient, or for 100 000 arthroplasties a total annual budget in France of £7 600000. If this approach achieved maximum efficacy, preventing the 150 fatal pulmonary embolisms corresponding to 100000 total hip replacements, the minimum direct cost would be £50 300 per life saved.

Conclusion:

Duplex screening may be more effective and lest costly than prolongation of prophylactic treatment using LMWH. This deduction needs to be confirmed by complex cost-benefit studies using clinical end-points.

Integration and added value of the modern noninvasive vascular laboratory in vascular diseases management

BACKGROUND AND PURPOSE

Today's vascular laboratory technology offers broad applications throughout vascular medicine. We explore the diagnostic work-up and management of selected peripheral vascular diseases by benchmarking the institutional mix of invasive and noninvasive technology utilization and associated cost burdens.

METHODS

Specialized diagnostic studies for prevention of stroke and pulmonary embolism, and diagnosis and management of femoral pseudoaneurysm were reviewed for our 355-physician clinic and hospital practice. The proportions and costs for invasive and noninvasive diagnostic procedures were tabulated for carotid stenosis, deep venous thrombosis (DVT), and iatrogenic femoral pseudoaneurysm. Current technology utilization mix cost burdens were compared to projected cost burdens for hypothetical equivalent medical value (i.e., the same total test volume) in the theoretical absence of noninvasive laboratory services.

RESULTS

The technology utilization mix was dominated by noninvasive duplex ultrasonography for all 3 vascular disease workups. The technology utilization mix benchmarks were 92% noninvasive for carotid stenosis, 98% noninvasive for DVT, and 100% noninvasive for pseudoaneurysm. Under hypothetical constant test volume normalized to utilization level for the 2-year period, the maximal range in cost burdens between current reliance on noninvasive diagnoses versus projected 100% reliance on invasive procedures for the 3 vascular applications is approximately $6 million.

CONCLUSION

Benchmark indices reveal near total adoption of noninvasive technology for vascular diagnostic workups at our center. The benefits to institutions of benchmarking their technology utilization mix and costs are discussed in relation to identifying potential for cost-containment from modifying technology utilization practices.

Perioperative management of selected problems in patients with rheumatic diseases

Patients undergoing surgery are subject to multiple perioperative problems. This article reviews several issues that occur in surgical patients with rheumatic diseases, including management of medications, diagnosis of fat embolism syndrome, prophylaxis against endocarditis, postoperative fever, and perioperative myocardial infarction.

Justification of intervention for limb-threatening ischemia: a surgical decision analysis

Intervention for vascular occlusive disease of the distal lower extremity in elderly patients will inevitably be scrutinized as medical resources decline. The authors applied surgical decision analysis to three treatment options: revascularization, amputation and expectant management. The appropriate outcome probabilities were derived from our experience with revascularization to the tibial and pedal vessels, and utility scores were obtained by formalized patient assessment. Revascularization was predicted to improve patient outcome by 1.10 quality-adjusted life-years compared with primary amputation and by 1.16 quality-adjusted life-years compared with expectant management. To gain one additional quality-adjusted life-years, revascularization would cost $5280 more than expectant management, but $33,900 less than primary amputation. Sensitivity analysis predicted revascularization to be the least costly treatment per quality-adjusted life-years as long as 1-month patency exceeds 11%. Revascularization for limb-threatening ischemia of the distal lower extremity is justified and can be performed at a reasonable cost.