Nationwide practice patterns for the use of venous thromboembolism prophylaxis among men undergoing radical prostatectomy

Purpose

To examine the practice patterns and predictors of VTE prophylaxis following radical prostatectomy (RP).

Methods

This was a population-based observational study of 94,709 men with a diagnosis of prostate cancer (ICD-9 code 185) who underwent RP were identified from a hospital-based database from 2000 to 2010, including 68,244 (72.1 %) open RP (ORP) and 26,465 (27.9 %) robotic-assisted laparoscopic RP (RALP). VTE prophylaxis was classified as none, mechanical, pharmacologic, or combination.

Results

Following RP, 35,591 (52.2 %) received mechanical, 4,945 (7.2 %) pharmacologic, 7,720 (10.6 %) combination, and 20,438 (30.0 %) no VTE prophylaxis. A total of 245 VTE events (145 DVT, 114 PE) were identified, representing 0.25 % of all procedures. Men with >2 comorbidities (OR = 2.44; 95 % CI 1.78–3.35) and those who were black (OR = 1.44; 95 % CI 1.06–1.97) were more likely to have a VTE. Men who had RALP (OR = 0.61; 95 % CI 0.45–0.99), surgery at high-volume hospitals (OR = 0.45; 95 % CI 0.28–0.73), or received prophylaxis (OR = 0.67; 95 % CI 0.50–0.88) were less likely to develop a VTE.

Conclusion

Despite the observation that VTE prophylaxis reduces the risk of VTE by 40 %, VTE prophylaxis was not used in almost one-third of men who underwent radical prostatectomy.     

The necessity of pharmacological prophylaxis against venous thromboembolism in major joint arthroplasty

Purpose

Venous thromboembolism (VTE) is a recognised post-operative complication of major lower limb joint arthroplasty. Current National Institute for Health and Clinical Excellence (NICE) guidelines suggest the use of both mechanical and pharmacological prophylaxis following hip and knee replacement. Since the introduction of enhanced recovery programmes following hip and knee arthroplasty the requirement for routine pharmacological VTE prophylaxis has been questioned. The purpose of this study was to assess the efficacy of pharmacological prophylaxis against symptomatic VTE in patients undergoing hip and knee arthroplasty under an enhanced recovery programme.

Methods

Symptomatic VTE incidence was audited in 1,100 patients undergoing primary or revision total hip or knee arthroplasty at the same hospital with only mechanical prophylaxis from 2007 to 2009. Following addition of chemical prophylaxis (enoxaparin) symptomatic VTE incidence in 522 patients undergoing primary or revision total hip or knee arthroplasty from 2011 to 2012 was re-audited.

Results

In the mechanical prophylaxis group incidence of DVT was 0.73 % [95 % confidence interval (CI) 0.37–1.43 %] and incidence of pulmonary embolism (PE) 0.91 % (95 % CI 0.49–1.67 %). Following addition of pharmacological prophylaxis incidence of DVT was 0.57 % (95 % CI 0.20–1.68 %) and incidence of PE 1.15 % (95 % CI 0.53–2.48 %).

Conclusions

We found no statistically significant difference in symptomatic VTE incidence following the addition of enoxaparin. We question whether routine pharmacological prophylaxis still has a role following total hip and knee arthroplasty. Peri-operative optimisation, including post-operative analgesia and mobility, with current enhanced recovery programmes may be sufficient. As anticoagulants carry increased risk of post-operative bleeding and wound ooze, in addition to significant cost implications, their role remains controversial.     

Vitamin K supplementation for the primary prevention of osteoporotic fractures: is it cost-effective and is future research warranted?

Summary

Lifetime supplementation with vitamin K, vitamin D₃, and calcium is likely to reduce fractures and increase survival in postmenopausal women. It would be a cost-effective intervention at commonly used thresholds, but high uncertainty around the cost-effectiveness estimates persists. Further research on the effect of vitamin K on fractures is warranted.

Introduction

Vitamin K might have a role in the primary prevention of fractures, but uncertainties about its effectiveness and cost-effectiveness persist.

Methods

We developed a state-transition probabilistic microsimulation model to quantify the cost-effectiveness of various interventions to prevent fractures in 50-year-old postmenopausal women without osteoporosis. We compared no supplementation, vitamin D₃ (800?IU/day) with calcium (1,200?mg/day), and vitamin K₂ (45?mg/day) with vitamin D₃ and calcium (at the same doses). An additional analysis explored replacing vitamin K₂ with vitamin K₁ (5?mg/day).

Results

Adding vitamin K₂ to vitamin D₃ with calcium reduced the lifetime probability of at least one fracture by 25%, increased discounted survival by 0.7 quality-adjusted life-years (QALYs) (95% credible interval (CrI) 0.2; 1.3) and discounted costs by $8,956, yielding an incremental cost-effectiveness ratio (ICER) of $12,268/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 95% and the population expected value of perfect information (EVPI) was $28.9 billion. Adding vitamin K₁ to vitamin D and calcium reduced the lifetime probability of at least one fracture by 20%, increased discounted survival by 0.4 QALYs (95% CrI ?1.9; 1.4) and discounted costs by $4,014, yielding an ICER of $9,557/QALY. At a $50,000/QALY threshold, the probability of cost-effectiveness was 80% while the EVPI was $414.9 billion. The efficacy of vitamin K was the most important parameter in sensitivity analyses.

Conclusions

Lifetime supplementation with vitamin K, vitamin D₃, and calcium is likely to reduce fractures and increase survival in postmenopausal women. Given high uncertainty around the cost-effectiveness estimates, further research on the efficacy of vitamin K on fractures is warranted.     

A Cost-Utility Analysis for Prophylactic Central Neck Dissection in Clinically Nodal-Negative Papillary Thyroid Carcinoma

Background

Although prophylactic central neck dissection (pCND) may reduce future locoregional recurrence after total thyroidectomy (TT) for low-risk papillary thyroid carcinoma (PTC), it is associated with a higher initial morbidity. We aimed to compare the long-term cost-effectiveness between TT with pCND (TT+pCND) and TT alone in the institution’s perspective.

Methods

Our case definition was a hypothetical cohort of 100,000 nonpregnant female patients aged 50 years with a 1.5-cm cN0 PTC within one lobe. A Markov decision tree model was constructed to compare the estimated cost-effectiveness between TT+pCND and TT alone after a 20-year period. Outcome probabilities, utilities, and costs were estimated from the literature. The threshold for cost-effectiveness was set at US$50,000 per quality-adjusted life year (QALY). Sensitivity and threshold analyses were used to examine model uncertainty.

Results

Each patient who underwent TT+pCND instead of TT alone cost an extra US$34.52 but gained an additional 0.323 QALY. In fact, in the sensitivity analysis, TT+pCND became cost-effective 9 years after the initial operation. In the threshold analysis, none of the scenarios that could change this conclusion appeared clinically possible or likely. However, TT+pCND became cost-saving (i.e., less costly and more cost-effective) at 20 years if associated permanent vocal cord palsy was kept ≤1.37 %, permanent hypoparathyroidism was ≤1.20 %, and/or postoperative radioiodine ablation use was ≤73.64 %.

Conclusions

In the institution’s perspective, routine pCND for low-risk PTC began to become cost-effective 9 years after initial surgery and became cost-saving at 20 years if postoperative radioiodine use and/or permanent surgical complications were kept to a minimum.     

The cost-effectiveness of strontium ranelate in the UK for the management of osteoporosis

Summary

The cost-effectiveness of strontium ranelate was compared to no treatment in UK women using the FRAX® algorithm for fracture risk assessment. At a willingness-to-pay of £30,000 per quality-adjusted life-year (QALY), strontium ranelate was generally cost-effective in women with prior fracture at the threshold of osteoporosis from an age of 65 years.

Introduction

The objectives of the study were to estimate the cost-effectiveness of strontium ranelate in the UK for the treatment of osteoporosis and to establish intervention thresholds for treatment using the FRAX® tool.

Methods

The cost-effectiveness of strontium ranelate was compared to no treatment in postmenopausal women with clinical risk factors for fracture using a lifetime simulation model based on Markov cohort methodology that incorporated the features of FRAX®.

Results

At a threshold of £30,000 per QALY, strontium ranelate was generally cost-effective in women from an age of 65 years with prior fracture at the threshold of osteoporosis (i.e., a T-score of ?2.5 SD) and in women with a prior fracture (and no information on bone mineral density) from the age of 65 years. At a threshold of £20,000, strontium ranelate became cost-effective at a 10-year fracture probability of 25.7% and at 16.9% with a threshold of £30,000 for a QALY.

Conclusions

Strontium ranelate is a cost-effective agent for the treatment of established osteoporosis in women over the age of 65 years. Cost-effective scenarios were also found for the prevention and treatment of fractures associated with osteoporosis, in younger women with additional clinical risk factors.     

Analytic model comparing the cost utility of TVT versus duloxetine in women with urinary stress incontinence

Introduction and hypothesis

The purpose of this study was to assess cost utility of duloxetine versus tension-free vaginal tape (TVT) as a second-line treatment for urinary stress incontinence.

Methods

A Markov model was used to compare the cost utility based on a 2-year follow-up period. Quality-adjusted life year (QALY) estimation was performed by assuming a disutility rate of 0.05.

Results

Under base-case assumptions, although duloxetine was a cheaper option, TVT gave a considerably higher QALY gain. When a longer follow-up period was considered, TVT had an incremental cost-effectiveness ratio (ICER) of £7,710 ($12,651) at 10 years. If the QALY gain from cure was 0.09, then the ICER for duloxetine and TVT would both fall within the indicative National Institute for Health and Clinical Excellence willingness to pay threshold at 2 years, but TVT would be the cost-effective option having extended dominance over duloxetine.

Conclusions

This model suggests that TVT is a cost-effective treatment for stress incontinence.     

Routine On-Site Evaluation of Specimen Adequacy During Initial Ultrasound-Guided Fine Needle Aspiration of Thyroid Nodules: A Cost-Effectiveness Analysis

Background

On-site evaluation (OSE) of specimen adequacy during fine needle aspiration (FNA) of thyroid nodules reduces unsatisfactory results but adds cost. We hypothesized that the addition of routine OSE to initial ultrasound-guided FNA of thyroid nodules is not cost-effective.

Methods

Formal cost-effectiveness analysis was performed using a decision model to compare strategies of routine initial OSE versus restriction of OSE to cases of prior inadequate FNA. Adequacy rates for FNA without OSE and detriment to quality-adjusted life expectancy (QALE) for undergoing repeat FNA were estimated on the basis of literature review and institutional experience. Costs were estimated using Medicare limiting charges and Bureau of Labor Statistics wage rates. Sensitivity analysis was used to examine the uncertainty of the model variable estimates.

Results

The routine OSE strategy produced a gain of 0.00007 quality-adjusted life-years (QALYs) at an additional cost of $43.75 for an incremental cost-effectiveness ratio of $639,143/QALY when compared to restriction of OSE to cases with prior inadequate results. During sensitivity analysis, routine OSE became cost-effective if FNA adequacy rate without OSE decreased from 90 to 85 %, cost of OSE decreased from $116 to $75, cost of FNA increased from $366 to $735, hourly wage increased from $23 to $123, or QALE detriment for repeat FNA increased from 0.25 to 1.6 days.

Conclusions

OSE for initial ultrasound-guided FNA of thyroid nodules is not cost-effective unless the adequacy rate without OSE is less than 85 %. When operator performance exceeds this rate, OSE should be reserved for cases with previous inadequate results.     

Abdominal sacral colpopexy versus sacrospinous ligament fixation: a cost-effectiveness analysis

Introduction and hypothesis

For the surgical correction of apical prolapse the abdominal approach is associated with better outcomes; however, it is more expensive than the transvaginal approach. This cost-effectiveness analysis compares abdominal sacral colpopexy (ASC) with sacrospinous ligament fixation (SSLF) to determine if the improved outcomes of ASC justify the increased expense.

Methods

A decision-analytic model was created comparing ASC with SSLF using data-modeling software, TreeAge Pro (2013), which included the following outcomes: post-operative stress urinary incontinence (SUI) with possible mid-urethral sling (MUS) placement, prolapse recurrence with possible re-operation, and post-operative dyspareunia. Cost-effectiveness was defined as an incremental cost-effectiveness ratio (ICER) of less than $50,000 per quality-associated life year (QALY). Base-case, threshold, and one-way sensitivity analyses were performed.

Results

At the baseline, ASC is more expensive than SSLF ($13,988 vs $11,950), but is more effective (QALY 1.53 vs 1.45) and is cost-effective (ICER $24,574/QALY) at 2 years. ASC was not cost-effective if the following four thresholds were met: the rate of post-operative SUI was above 36 % after ASC or below 28 % after SSLF; the rate of MUS placement for post-operative SUI was above 60 % after ASC or below 13 % after SSLF; the rate of recurrent prolapse was above 15 % after ASC or below 4 % after SSLF; the rate of post-operative dyspareunia was above 59 % after ASC or below 19 % after SSLF.

Conclusions

Abdominal sacral colpopexy can be cost-effective compared with sacrospinous ligament fixation; however, as the post-operative outcomes of SSLF improve, SSLF can be considered a cost-effective alternative.

     

Safety of fondaparinux to prevent venous thromboembolism in Japanese patients undergoing colorectal cancer surgery: a multicenter study

Purpose

To investigate the safety and efficacy of fondaparinux (FPX) for venous thromboembolism (VTE) prophylaxis in Japanese patients undergoing colorectal cancer surgery.

Methods

The subjects of this multicenter, open-label, prospective observational study were patients undergoing resection of the colon/rectum for colorectal cancer. All patients were given FPX 2.5 or 1.5 mg by subcutaneous injection, once daily for 4–8 days, starting 24 h after surgery. The primary endpoint was any major bleeding event and the secondary endpoint was any symptomatic VTE event.

Results

Between February 2009 and December 2010, 619 patients from 23 institutions were enrolled in this study. The median duration of FPX prophylaxis was 4 days. The incidence of major bleeding was 0.81 % [5/619, 95 % confidence interval (CI) 0.3–1.9] and the incidence of minor bleeding was 9.5 % (59/619, 95 % CI 7.3–12.1). There was no fatal bleeding or symptomatic VTE. Multivariable analysis revealed the following to be risk factors for bleeding events: preoperative platelet count <15 × 10⁴/µl [odds ratio (OR) 4.521], male sex (OR 2.078), and blood loss during surgery <50 ml (OR 2.019).

Conclusion

The administration of 2.5/1.5 mg FPX 24 h after colorectal cancer surgery is safe and effective.     

A cost-effectiveness comparisons of adult spinal deformity surgery in the United States and Japan

Purpose

Information about the cost-effectiveness of surgical procedures for adult spinal deformity (ASD) is critical for providing appropriate treatments for these patients. The purposes of this study were to compare the direct cost and cost-effectiveness of surgery for ASD in the United States (US) and Japan (JP).

Methods

Retrospective analysis of 76 US and 76 JP patients receiving surgery for ASD with ≥2-year follow-up was identified. Data analysis included preoperative and postoperative demographic, radiographic, health-related quality of life (HRQOL), and direct cost for surgery. An incremental cost-effectiveness ratio (ICER) was determined using cost/quality-adjusted life years (QALY). The cost/QALY was calculated from the 2-year cost and HRQOL data.

Results

JP exhibited worse baseline spinopelvic alignment than the US (pelvic incidence and lumbar lordosis: 35.4° vs 22.7°, p < 0.01). The US had more three-column osteotomies (50 vs 16%), and shorter hospital stay (7.9 vs 22.7 days) (p < 0.05). The US demonstrated worse postoperative ODI (41.3 vs. 33.9%) and greater revision surgery rate (40 vs 10%) (p < 0.05). Due to the high initial cost and revision frequency, the US had greater total cost ($92,133 vs. $49,647) and cost/QALY ($511,840 vs. $225,668) at 2-year follow-up (p < 0.05).

Conclusion

Retrospective analysis comparing the direct costs and cost-effectiveness of ASD surgery in the US vs JP demonstrated that the total direct costs and cost/QALY were substantially higher in the US than JP. Variations in patient cohort, healthcare costs, revision frequencies, and HRQOL improvement influenced the cost/QALY differential between these countries.

     

Venous thromboembolism after laparoscopic cholecystectomy: clinical burden and prevention

Background

The clinical benefit of prophylaxis for venous thromboembolism (VTE) in laparoscopic cholecystectomy is unclear. This study aimed to assess the clinical burden of VTE and the efficacy and safety of antithrombotic prophylaxis during laparoscopic cholecystectomy.

Methods

Data sources and study selection studies were searched in MEDLINE and Embase using the terms “cholecystectomy and venous thrombosis” and “cholecystectomy and venous thromboembolism.” Studies were considered for a systematic review and a metaanalysis if they reported on the methods of antithrombotic prophylaxis and on the incidence of objectively confirmed VTE in patients who had undergone laparoscopic cholecystectomy. Overall, 15 studies of patients who had undergone laparoscopic cholecystectomy were included in the systematic review.

Results

The incidence of VTE was lower after laparoscopic cholecystectomy than after open cholecystectomy [odds ratio (OR), 0.47; 95 % confidence interval (CI), 0.40–0.56]. No statistically significant reduction in VTE was observed in patients receiving heparin prophylaxis after laparoscopic cholecystectomy (OR, 0.86; 95 % CI, 0.12–5.82).

Conclusions

The rate of VTE after laparoscopic cholecystectomy seems to be relatively low. The clinical benefit of heparin prophylaxis for patients undergoing laparoscopic cholecystectomy remains unclear.     

Cost-effectiveness of mediastinal lymph node staging in non–small cell lung cancer

Objective

To assess the cost-effectiveness of various modes of mediastinal staging in non–small cell lung cancer (NSCLC) in a single-payer health care system.

Optimal Prophylactic Method of Venous Thromboembolism for Gastrectomy in Korean Patients: An Interim Analysis of Prospective Randomized Trial

Background

Whereas routine prophylaxis for venous thromboembolism (VTE) is frequently utilized in the West, Asian physicians employ it much less often, based on its recorded rarity amongst their patients. This study was designed to examine the incidence of VTE and to determine the optimal method of thromboembolic prophylaxis following gastrectomy for cancer.

Methods

In this prospective, randomized trial, patients were assigned to either an intermittent pneumatic compression (IPC) only or an IPC plus enoxaparin. The primary end point of this study was to determine the VTE incidence rate within 30 days of surgery. A history with physical examinations for VTE and a serum d-dimer test was scheduled on postoperative days (POD) 0, 1, 4, and 7. Duplex ultrasonography (DUS) was performed as an objective test for deep vein thrombosis at POD 4. An interim analysis was performed to determine if it was ethical to continue the study. This clinical trial was registered at www.clinicaltrials.gov (NCT01448746).

Results

Among the 220 patients, 3 (all from the IPC group) were diagnosed with VTE; these cases were asymptomatic, having been detected only on DUS 4 days after surgery. Postoperative bleeding occurred in 12 cases, among which 11 patients were in the IPC plus enoxaparin group.

Conclusions

This interim analysis showed a higher incidence of VTE in the IPC group but a higher bleeding rate in the IPC plus enoxaparin group. We expect that this study, once completed, will provide information key to the determination of the optimal method for preventing VTE in Korean gastric cancer patients.     

Cost-Effectiveness of Minimally Invasive Versus Open Esophagectomy for Esophageal Cancer

Background

A recent randomized trial comparing minimally invasive (MIE) and open esophagectomy for esophageal cancer reported improved short-term outcomes. However, MIE has increased operative costs, and it is unclear whether the short-term benefits of MIE outweigh the increased operative costs. Therefore, the objective of this study was to determine the cost-effectiveness of MIE compared to open esophagectomy for esophageal cancer.

Methods

A decision-analysis model was developed to estimate the expected costs and outcomes after MIE and open esophagectomy from a health care system perspective with a time horizon of 1 year. Costs were represented in 2012 Canadian dollars, and effectiveness was measured in quality-adjusted life-years (QALYs). Probabilistic sensitivity analysis assessed parameter uncertainty.

Results

MIE was estimated to cost $1641 (95 % confidence interval 1565, 1718) less than open esophagectomy, with an incremental gain of 0.022 QALYs (95 % confidence interval 0.021, 0.023). MIE was therefore dominant over open esophagectomy. On deterministic sensitivity analyses, the results were most sensitive to variations in length of stay. Probabilistic sensitivity analysis demonstrated the robustness of the base case result, with 66, 77, and 82 % probabilities of cost-effectiveness at willingness-to-pay thresholds of $0/QALY, $50,000/QALY, and $100,000/QALY, respectively.

Conclusions

MIE is cost-effective compared to open esophagectomy in patients with resectable esophageal cancer.     

The Impact of Surgical Complications as a Main Risk Factor for Venous Thromboembolism: A Multicenter Study

Background

Studies suggest that postoperative complications are a risk factor for venous thromboembolism (VTE) after bariatric surgery. Knowledge of factors associated with a higher risk of VTE after bariatric surgery may be essential to select patients who may benefit from either prolonged or intensified thrombosis prophylaxis. The aim of this study is to determine the relationship between postoperative complications and VTE after bariatric surgery and other classical risk factors.

Methods

A retrospective multicenter case-control study was performed in patients who had bariatric surgery between January 2008 and September 2011. VTE until 6 months after surgery was registered, and patients were contacted to ascertain the results. For every case of VTE after surgery, 6 control patients were selected who were matched for gender, age, participating center and type of surgery. Risk factors for VTE before and after surgery and postoperative complications were registered.

Results

A total of 2,064 surgeries were included. In 12 patients, VTE occurred within 6 months after bariatric surgery (incidence 0.58 %, 95 % confidence interval (CI)?=?0.25–0.93). There was a strong association of complications after surgery (cases 91.7 %, controls 15.3 %, odds ratio (OR) 61.0; 95 % CI?=?7.1–521.3) or intensive care admission (cases 50.0 %, controls 11.1 %, OR?=?8.0; 95 % CI?=?2.1–30.8) with VTE. The majority of postoperative complications were anastomotic leak, abdominal abscess, and infection. We could not detect an association between classical thrombosis risk factors and postoperative VTE.

Conclusions

The incidence of VTE is low after bariatric surgery using thrombosis prophylaxis. However, there is a strong association between postoperative complications and VTE. These patients may benefit from more intensive thrombosis prophylaxis.     

Defining Incidence and Risk Factors of Venous Thromboemolism after Hepatectomy

Background

The incidence of venous thromboembolism (VTE) among patients undergoing hepatic surgery is poorly defined, leading to varied use of VTE prophylaxis among surgeons. We sought to define the incidence of VTE after liver surgery and identify risk factors associated with VTE.

Methods

Incidence of VTE and associated risk factors within 90 days of hepatic resection between 2006 and 2012 at a major academic center was analyzed. Risk factors for VTE were identified using univariate and multivariate analyses.

Results

A total of 599 patients were included in the study cohort; 30 (5.0 %) had a prior history of VTE. The indications for surgery were malignant (90.8 %) and benign lesions (9.2 %). The majority of patients underwent a minor hepatectomy (<3 Couinaud segments; n?=?402, 67.1 %) while 195 (32.6 %) patients underwent a major hepatectomy (≥3 Couinaud segments). Three hundred seven (51.3 %) patients were started on VTE chemoprophylaxis preoperatively with 407 (67.8 %) patients receiving VTE chemoprophylaxis within 24 h of surgery. Twenty-eight (4.7 %) patients developed VTE; 20 (3.3 %) had deep venous thrombosis (DVT), 11 (1.8 %) had pulmonary embolism (PE), and three (0.5 %) developed both DVT and PE. Among the VTE patients, 23 (82.1 %) had received VTE chemoprophylaxis. On multivariate analyses, history of VTE (odds ratio [OR] 4.51, 95 % confidence interval [CI] 1.81–17.22, P?=?0.03), prolonged operative time (OR 1.17 per additional hour, 95 % CI 1.04–1.32, P?=?0.009), and increased length of stay (LOS) (OR 1.07, 95 % CI 1.02–1.12, P?=?0.01) were independent risk factors for VTE.

Conclusion

VTE within 90 days of hepatic resection is common, occurring in nearly one in 20 patients. Most VTE events occurred among patients who received current best practice prophylaxis for VTE. More aggressive strategies to identify and reduce the risk of VTE in patients at highest risk of VTE, including those with a history of VTE, extended operative time, and prolonged LOS, are warranted.     

Cost-effectiveness of training rural providers to identify and treat patients at risk for fragility fractures

Summary

This is a cost-effectiveness analysis of training rural providers to identify and treat osteoporosis. Results showed a slight cost savings, increase in life years, increase in treatment rates, and decrease in fracture incidence. However, the results were sensitive to small differences in effectiveness, being cost-effective in 70 % of simulations during probabilistic sensitivity analysis.

Introduction

We evaluated the cost-effectiveness of training rural providers to identify and treat veterans at risk for fragility fractures relative to referring these patients to an urban medical center for specialist care. The model evaluated the impact of training on patient life years, quality-adjusted life years (QALYs), treatment rates, fracture incidence, and costs from the perspective of the Department of Veterans Affairs.

Methods

We constructed a Markov microsimulation model to compare costs and outcomes of a hypothetical cohort of veterans seen by rural providers. Parameter estimates were derived from previously published studies, and we conducted one-way and probabilistic sensitivity analyses on the parameter inputs.

Results

Base-case analysis showed that training resulted in no additional costs and an extra 0.083 life years (0.054 QALYs). Our model projected that as a result of training, more patients with osteoporosis would receive treatment (81.3 vs. 12.2 %), and all patients would have a lower incidence of fractures per 1,000 patient years (hip, 1.628 vs. 1.913; clinical vertebral, 0.566 vs. 1.037) when seen by a trained provider compared to an untrained provider. Results remained consistent in one-way sensitivity analysis and in probabilistic sensitivity analyses, training rural providers was cost-effective (less than $50,000/QALY) in 70 % of the simulations.

Conclusions

Training rural providers to identify and treat veterans at risk for fragility fractures has a potential to be cost-effective, but the results are sensitive to small differences in effectiveness. It appears that provider education alone is not enough to make a significant difference in fragility fracture rates among veterans.     

Symptomatic venous thromboembolism in Asian major trauma patients: incidence, presentation and risk factors

Background

Trauma patients are known to be at increased risk of venous thromboembolism (VTE), and pulmonary embolism (PE) is one of the preventable causes of mortality in trauma patients. The incidence of VTE in Asian populations was believed to be lower than in Caucasians, but the recent literature suggests that this is not the case. The purpose of this study was to assess the incidence of VTE in Asian major trauma patients and to examine the manner of presentation, use of prophylaxis and risk factors for VTE. While other studies of VTE have addressed general and high-risk populations within Asia, our study is one of the few to examine Asian major trauma patients.

Methods

Data for all patients with VTE were extracted from the Singapore General Hospital trauma database over a 10-year period from 1998 to 2007. Patient profiles and clinical factors were compared to patients without a diagnosis of VTE admitted with injuries in the same time period.

Results

There were 8,615 patients entered into our database in this 10-year period. Thirty-four patients had VTE, with an overall incidence of 0.39 %. Thirteen patients had pulmonary embolism, an incidence of 0.15 %. Of note, 30 % of patients with deep vein thrombosis (DVT) presented with fever alone without limb symptoms. Almost all 34 patients who developed VTE had either head injury, a spinal cord injury or a pelvic/extremity injury. Eighteen patients had head injury, 22 patients sustained pelvic or extremity injury, and three patients had spinal cord injury with paraplegia. Head injury and spinal cord injury with neurologic sequelae were statistically significant risk factors for VTE (p < 0.05).

Conclusion

The incidence of symptomatic VTE in the Asian trauma population is no lower than in the West. The incidence found in this study is similar to the incidence of VTE according to a study using data from the American national trauma data bank using similar study methods and with a similar study population. It is also higher than the incidence in the literature for general post-surgical Asian patients. Fever was the presenting factor in some patients and screening for VTE should not be forgotten when assessing fever in the trauma patient. The strong association between head injury, spinal cord injury and VTE confirms that we should pay special attention to VTE prophylaxis for our patients with these injuries.     

Venous thromboembolism after lower limb arthroplasty: is chemical prophylaxis still needed?

Background

Venous thromboembolism (VTE) is a significant complication of lower limb arthroplasty. The National Institute for Health and Care Excellence recommends routine use of chemical and mechanical prophylaxis to prevent VTE. Our high-volume, elective, arthroplasty unit adopted this guidance in 2008.

Purpose

We examined our incidence of VTE before and after introduction of chemical thromboprophylaxis to determine whether the incidence of VTE reduced.

Methods

We retrospectively gathered data on 2 cohorts of patients—from January 2004 to August 2007 (Group 1) and January 2010 to December 2012 (Group 2). Patients in Group 1 received mechanical prophylaxis only (unless particularly high risk for VTE), and patients in Group 2 received mechanical and chemical prophylaxis. We recorded VTE occurring within 6 months of surgery. Patients in Group 1 receiving chemical prophylaxis were excluded.

Results

Group 1 had 2320 cases of primary and revision lower limb arthroplasty, and Group 2 had 1430 cases. VTE occurred in 37 cases in Group 1 (1.6 %), and in 17 cases in Group 2 (1.2 %). This difference was not statistically significant (p = 0.26). In Group 1, 1 patient died within 6 months due to pulmonary embolism (0.04 %); there were no VTE-related deaths in Group 2 (0 %). This was also not statistically significant (p = 0.06).

Conclusions

Although our VTE rate reduced by 0.4 % and our VTE-related mortality reduced by 0.04 % after introduction of chemical thromboprophylaxis, these differences were not statistically significant. Chemical thromboprophylaxis may not be required in all patients undergoing arthroplasty providing appropriate mechanical prophylaxis is used.

     

Dalteparin versus Enoxaparin for the prevention of venous thromboembolic events in trauma patients

Background

The use of low-molecular-weight heparin (LMWH) for the chemoprophylaxis of venous thromboembolism (VTE) in trauma patients is supported by Level-1 evidence. Because Enoxaparin was the agent used in the majority of studies for establishing the efficacy of LMWH in VTE, it remains unclear if Dalteparin provides an equivalent effect.

Objective

To compare Dalteparin to Enoxaparin and investigate their equivalence as VTE prophylaxis in trauma.

Patients/setting

Trauma patients receiving VTE chemoprophylaxis in the Surgical Intensive Care Unit of a Level-1 Trauma Center from 2009 (Enoxaparin) to 2010 (Dalteparin) were included.

Measurements

The primary outcome was the incidence of clinically significant VTE. Secondary outcomes included heparin-induced thrombocytopenia (HIT), major bleeding, and drug acquisition cost savings. Equivalence margins were set between ?5 and 5 %.

Main results

A total of 610 patient records (277 Enoxaparin, 333 Dalteparin) were reviewed. The two study groups did not differ significantly: blunt trauma 67 vs. 62 %, p = 0.27; mean Injury Severity Score (ISS) 17 ± 10 vs. 16 ± 10, p = 0.34; Acute Physiology and Chronic Health Evaluation (APACHE) II score 17 ± 9 vs. 17 ± 10, p = 0.76; time to first dose of LMWH 69 ± 98 vs. 65 ± 67 h, p = 0.57). The rates of deep venous thrombosis (DVT) (3.2 vs. 3.3 %, p = 1.00), pulmonary emboli (PE) (1.8 vs. 1.2 %, p = 0.74), and overall VTE (5.1 vs. 4.5 %, p = 0.85) did not differ. The absolute difference in the incidence of overall VTE was 0.5 % [95 % confidence interval (CI): ?2.9, 4.0 %, p = 0.85]. The 95 % CI was within the predefined equivalence margins. There were no significant differences in the frequency of HIT or major bleeding. The total year-on-year cost savings, achieved with 277 patients during the switch to Dalteparin, was estimated to be $107,778.

Conclusions

Dalteparin is equivalent to Enoxaparin in terms of VTE in trauma patients and can be safely used in this population, with no increase in complications and significant cost savings.