脑卒中康复患者静脉血栓的发病率及对功能的影响北大核心CSCD

目的回顾性分析康复病房中脑卒中恢复期患者静脉血栓疾病的发生率及其对功能预后的影响。方法回顾性分析2015年1月至2020年10月北京博爱医院神经康复病房脑卒中住院患者3557例。统计人口学特征、卒中特点(类型、部位)、实验室指标(D-二聚体、动脉氧分压)、运动功能(Brunnstrom分期、FuglMeyer运动和平衡评分、小腿三头肌改良Ashworth评分、Holden步行功能分级)、日常生活活动能力(Barthel指数),以及抗凝剂/抗血小板治疗数据。结果下肢静脉血栓和肺栓塞的发生率分别为28.5%和1.29%,多数发生在发病30 d后。相比脑出血,缺血性脑卒中患者发生肺栓塞风险更高(χ^(2)=12.49,P<0.001),年龄更大(t=2.501,P<0.05);大面积脑卒中、严重下肢瘫痪和日常生活活动能力低下的患者更易发生静脉血栓栓塞疾病。并发肺栓塞患者经过康复,功能和日常生活活动能力均比入院时显著改善(|t|>4.302,P<0.001)。结论康复病房中脑卒中恢复期患者下肢静脉血栓和肺栓塞的发生率不容忽视。应根据风险因素对患者进行分层,年龄较大、既往有血栓形成史、大面积脑卒中和严重肢体瘫痪的患者风险更大。并发肺栓塞患者,如抗凝治疗有效,可早期开展个体化全面康复,以改善其功能预后和日常生活活动能力。     

Incidence of venous thromboembolism in hospitalized patients vs community residents.

OBJECTIVE: To estimate the incidence rates of deep venous thrombosis (DVT) and pulmonary embolism (PE) in hospitalized patients and to compare these with incidence rates in community residents. PATIENTS AND METHODS: We performed a retrospective review of the complete medical records from a population-based inception cohort of patients who resided in Olmsted County, Minnesota, and had an incident DVT or PE from 1980 through 1990. RESULTS: From 1980 through 1990, 911 Olmsted County residents experienced their first lifetime event of definite, probable, or possible venous thromboembolism. Of these residents, 253 had been hospitalized for some reason other than a diagnosis of DVT or PE (in-hospital cases), and 658 were not hospitalized at onset of venous thromboembolism (community residents). The average annual age- and sex-adjusted incidence of in-hospital venous thromboembolism was 960.5 (95% confidence interval, 795.1-1125.9) per 10,000 person-years and was more than 100 times greater than the incidence among community residents at 7.1 (95% confidence interval, 6.5-7.6) per 10,000 person-years. The incidence of venous thromboembolism rose markedly with increasing age for both groups, with PE accounting for most of the age-related increase among in-hospital cases. Incidence rates in the 2 groups changed little over time despite a reduction in the average length of hospital stay between 1980 and 1990. CONCLUSIONS: Venous thromboembolism is a major national health problem, especially among elderly hospitalized patients. This finding emphasizes the need for accurate identification of hospitalized patients at risk for venous thromboembolism and a better understanding of the mechanisms involved so that safe and effective prophylaxis can be implemented.     

Burden of illness in venous thromboembolism in critical care: a multicenter observational study

PURPOSE: The frequency of clinically diagnosed venous thromboembolism (VTE) including deep venous thrombosis (DVT) and pulmonary embolism (PE) in medical-surgical critically ill patients is unclear. The objectives of this study were to estimate the prevalence and incidence of radiologically confirmed DVT and PE in medical-surgical intensive care unit (ICU) patients and to determine the impact of prophylaxis on the frequency of these events. MATERIALS AND METHODS: In a retrospective observational cohort study in 12 adult ICUs, we identified prevalent cases (diagnosed in the 24 hours preceding ICU admission up to 48 hours post-ICU admission) and incident cases (diagnosed 48 hours or more after ICU admission and up to 8 weeks after ICU discharge) of upper or lower limb DVT or PE. Deep venous thrombosis was diagnosed by compression ultrasound or venogram. Each DVT was classified as clinically suspected or not clinically suspected in that the latter was diagnosed by scheduled screening ultrasonography. Pulmonary embolism was diagnosed by ventilation-perfusion lung scan, computed tomography pulmonary angiography, echocardiography, electrocardiography, or autopsy. RESULTS: Among 12,338 patients, 252 (2.0%) patients had radiologically confirmed DVT or PE and another 47 (0.4%) had possible DVT or PE. Prevalent DVTs were diagnosed in 0.4% (95% confidence interval [CI], 0.3%-0.5%) of patients and prevalent PEs were diagnosed in 0.4% (95% CI, 0.3%-0.6%). Incident DVTs were diagnosed in 1.0% (95% CI, 0.8%-1.2%) of patients, and incident PEs were diagnosed in 0.5% (95% CI, 0.4%-0.6%). Of patients with incident VTE, 65.8% of cases occurred despite receipt of thromboprophylaxis for at least 80% of their days in ICU. The median (interquartile range) ICU length of stay was similar for patients with DVT (7 [3-17]) and PE (5 [2-8]). For all patients with VTE, ICU mortality was 16.7% (95% CI, 12.0%-21.3%) and hospital mortality was 28.5% (95% CI, 22.8%-34.1%). CONCLUSIONS: Venous thromboembolism appears to be an apparently infrequent, but likely underdiagnosed problem, occurring among patients receiving prophylaxis. Findings suggest the need for increased suspicion among clinicians, renewed efforts at thromboprophylaxis, and evaluation of superior prevention strategies.     

Incidence, risk profile and morphological pattern of venous thromboembolism after prostate cancer surgery

Summary.  Background : Venous thromboembolism (VTE) is the most common non-surgical complication after major pelvic surgery. Little is known about the risk factors or the time of development of postoperative venous thrombosis. Methods: A cohort of 523 consecutive patients undergoing radical prostatectomy with lymphadenectomy was prospectively assessed by complete compression ultrasound at days −1, +8 and +21. Results: Complete data were available in 415 patients, while four patients had VTE before surgery and were excluded from the analysis. In the remaining 411 patients, 71 VTE events were found in 69 patients (16.8%). Most were limited to calf muscle veins (56.5%), followed by deep calf vein thrombosis (23.2%), proximal deep vein thrombosis (DVT, 14.5%) and pulmonary embolism (PE, 5.8%). Of the 14 patients with proximal DVT/PE, 11 patients (78.6%) developed VTE between days 8 and 21. Risk factors for VTE were a personal history of VTE (OR 3.0), pelvic lymphoceles (LCs) impairing venous flow (OR 2.8) and necessity of more than two units of red blood cells (OR 2.6). Conclusion: Venous thromboembolism is common after radical prostatectomy. A significant proportion develops after day 8, suggesting that prolonged heparin prophylaxis should be considered. Since LCs with venous flow reduction result in higher rates of VTE, hemodynamically relevant lymphoceles should be surgically treated.     

Incidence of symptomatic venous thromboembolism following hematopoietic stem cell transplantation

Summary.  Background: The incidence of symptomatic venous thromboembolism (VTE) following hematopoietic stem cell transplantation (HSCT) is not well described, particularly with increased use of ambulatory care in the transplant setting. Methods: A retrospective analysis involving 589 patients (382 autologous HSCT, 207 allogeneic HSCT) undergoing transplantation between 2000 and 2005 in a single Canadian institution was undertaken to identify the incidence of proximal deep vein thrombosis (DVT) or pulmonary embolism (PE) in HSCT patients. Results: The total 1-year incidence of symptomatic VTE was 3.7% [95% confidence interval (CI) 2.5–5.6]. Among the HSCT patients, 7/589 (1.2%, 95% CI  0.6–2.4) developed symptomatic non-catheter-related VTE following HSCT (four PE and three DVT). All VTE events occurred after hematopoietic engraftment. Patients undergoing autologous HSCT did not receive thromboprophylaxis, whereas most patients undergoing allogeneic HSCT (79.7%) received enoxaparin 20 mg daily for the prevention of veno-occlusive disease of the liver, starting 6 ± 3 days before transplantation for a mean of 22 ± 14 days. Conclusion: HSCT patients have a high incidence of VTE. Thromboprophylaxis should potentially be considered in these patients. However, future studies assessing the risk and benefits of thromboprophylaxis are needed in this specific population.     

Thromboembolic Risk in Hospitalized and Nonhospitalized COVID-19 Patients: A Self-Controlled Case Series Analysis of a Nationwide Cohort

ObjectiveTo assess the associations between coronavirus disease 2019 (COVID-19) infection and thromboembolism including myocardial infarction (MI), ischemic stroke, deep vein thrombosis (DVT), and pulmonary embolism (PE).Patients and MethodsA self-controlled case-series study was conducted covering the whole of Scotland’s general population. The study population comprised individuals with confirmed (positive test) COVID-19 and at least one thromboembolic event between March 2018 and October 2020. Their incidence rates during the risk interval (5 days before to 56 days after the positive test) and the control interval (the remaining periods) were compared intrapersonally.ResultsAcross Scotland, 1449 individuals tested positive for COVID-19 and experienced a thromboembolic event. The risk of thromboembolism was significantly elevated over the whole risk period but highest in the 7 days following the positive test (incidence rate ratio, 12.01; 95% CI, 9.91 to 14.56) in all included individuals. The association was also present in individuals not originally hospitalized for COVID-19 (incidence rate ratio, 4.07; 95% CI, 2.83 to 5.85). Risk of MI, stroke, PE, and DVT were all significantly higher in the week following a positive test. The risk of PE and DVT was particularly high and remained significantly elevated even 56 days following the test.ConclusionConfirmed COVID-19 infection was associated with early elevations in risk with MI, ischemic stroke, and substantially stronger and prolonged elevations with DVT and PE both in hospital and community settings. Clinicians should consider thromboembolism, especially PE, among people with COVID-19 in the community.     

Deep venous thrombosis in high-risk hemiplegic patients: detection by impedance plethysmography

Clinically significant thromboembolic disease originating from the paralyzed leg of hemiplegic patients can occur unexpectedly and may affect morbidity and mortality in the rehabilitation setting. Impedance plethysmography (IPG), a simple, noninvasive technique, can accurately reveal deep vein thrombosis (DVT) in the large veins of the thigh. IPG studies were performed on the lower extremities of 20 hemiplegic patients considered at high risk for DVT. Each patient had one or several of the following potential risk factors: mild swelling, vague leg discomfort, loss of sensation, poor or absent muscle power at the ankle, at least one week of complete bedrest, repeated minor trauma. None of the patients had major signs or symptoms of DVT at the time of testing (ie, severe pain and tenderness, increased temperature or redness, a palpable venous cord, or positive Homans' sign). Seven patients had an abnormal IPG in the paralyzed lower limb and DVT was confirmed in each case by venography. After appropriate anticoagulation therapy, the seven patients resumed their rehabilitation programs. It was concluded that IPG can be successfully used in the early detection of DVT in high-risk hemiplegic patients, thus leading to prompt medical management, reduced morbidity and mortality, and improved rehabilitation outcome.     

Prevalence and Risk Factors of Asymptomatic Lower Extremity Deep Venous Thrombosis in Asian Neurorehabilitation Admissions in Singapore

Chua K, Kong KH, Chan SP. Prevalence and risk factors of asymptomatic lower extremity deep venous thrombosis in Asian neurorehabilitation admissions in Singapore.

Objective

To determine the local prevalence and risk factors of asymptomatic lower limb deep venous thrombosis (DVT) among neurorehabilitation admissions.

Design

A prospective observational single-center study.

Setting

Tertiary rehabilitation center affiliated to a public hospital.

Participants

A total of 419 Asian neurorehabilitation admissions with a mean of 26 days to rehabilitation.

Intervention

Admission screening protocol included quantitative D-dimer assay within 24 to 48 hours of rehabilitation admission and targeted hemiplegic/weaker lower-extremity venous duplex ultrasonography was performed if D-dimer assay level was elevated at 0.34 μg/mL or higher.

Main Outcome Measures

There were 251 (59.9%) men, and the subjects were predominantly Chinese (76.6%). Subjects had a mean age of 59±15 years. Admitting diagnoses included ischemic stroke (212), hemorrhagic stroke and subarachnoid hemorrhage (129), traumatic brain injury (59), and nontraumatic brain injury (19). The screening protocol included a quantitative D-dimer assay within 24 to 48 hours of rehabilitation admission, and hemiplegic/weaker lower-extremity venous duplex ultrasonography was performed if D-dimer assay level was elevated at 0.34 μg/mL or higher.

Results

Altogether, 247 (58.9%) patients had an elevated D-dimer assay, and all underwent venous duplex ultrasonography. The incidence of lower-limb DVT was 5.01% (21), including 11 proximal and 10 distal DVT. No patients had clinical pulmonary embolism. Using 247 venous duplex ultrasonography results for analyses of correlates with logistic regression analyses, no significant demographic or clinical predictive factors for DVT were found.

Conclusions

This study confirms that asymptomatic lower limb DVT is indeed uncommon in Asian neurorehabilitation admissions. Possible reasons include genetic or ethnic protective factors, early walking initiated at rehabilitation, and timing of the admission protocol (median of 14 days postevent) when the maximal thrombotic risk was on the decline.     

Cost-effectiveness of screening for deep vein thrombosis by ultrasound at admission to stroke rehabilitation

OBJECTIVE: This project was a cost-effectiveness analysis of the practice of routine Doppler ultrasound screening for deep vein thrombosis (DVT) in patients with ischemic stroke at the time of admission to rehabilitation. DESIGN: A decision-analysis model was created to compare 2 approaches for detecting DVT in a stroke population: (1) screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment; or (2) clinical surveillance for signs of DVT and treatment after confirmation by Doppler ultrasound. The prevalence of DVT, risk of complication from DVT, and risk of complication from treatment were obtained from published reports. Costs are in 2004 dollars and the effectiveness was measured in quality-adjusted life-years (QALYs) gained. We conducted these analyses from a societal perspective. SETTING: Inpatient stroke rehabilitation unit. PARTICIPANTS: Not applicable. INTERVENTION: Screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment. MAIN OUTCOME MEASURE: Cost in 2004 dollars per QALY gained by screening all patients with acute ischemic stroke at admission to stroke rehabilitation for DVT by Doppler ultrasound with subsequent treatment. RESULTS: The expected utility of screening patients with ischemic stroke for DVT by Doppler ultrasound on admission to rehabilitation is 1.875 QALYs and that of not screening is 1.872 QALYs. The expected gain is .0026 QALYs (23 h). Obtaining this increase in quality-adjusted life incurs additional cost of 168 dollars per stroke patient and a marginal cost-effectiveness of 67,200 dollars for each QALY gained. CONCLUSIONS: This study estimates that the cost-effectiveness ratio is considerably higher than that reported in other rehabilitation conditions and higher than the commonly stated level for an intervention to be considered cost-effective. The difference from previous reports primarily relates to the shorter life expectancy following stroke, the prevalence of occult DVT at admission, rate of complications of anticoagulation, and the estimates of the screening's test characteristics used in our study. Further study of these areas is likely to contribute to improving our understanding of the most appropriate care of these patients.     

Incidence of cancer after a first episode of idiopathic venous thromboembolism treated with 3 months or 1 year of oral anticoagulation

Summary.  Background : A prolonged treatment with oral anticoagulants has been claimed to reduce the incidence of newly diagnosed cancer in the long-term follow-up of patients with venous thromboembolism. Objectives : In a multicenter prospective study we assessed the incidence of newly diagnosed clinically overt cancer in patients with a first episode of idiopathic venous thromboembolism (VTE) treated with oral anticoagulants for 3 months or 1 year. Patients and methods : Consecutive patients with an idiopathic venous thromboembolism who had completed 3 months of oral anticoagulant therapy without having a recurrence, bleeding or newly diagnosed cancer were randomized to discontinue oral anticoagulant therapy or to continue it for nine additional months. Idiopathic venous thromboembolism was defined as thrombosis occurring in the absence of known cancer, known thrombophilia, or temporary risk factors for venous thromboembolism. All patients were followed up for at least 1 year after randomization. Results : A total of 429 patients, 265 patients with DVT and 164 with PE, were followed up for an average of 43.7 months after randomization. A newly diagnosed cancer occurred in 32 patients (7.5%), 13 (6.2%) of the 210 patients treated for 3 months and 19 (8.7%) of the 219 patients treated for 1 year (RR = 0.71, 95% confidence interval 0.36–1.41). Conclusions : The incidence of newly diagnosed clinically overt cancer is not reduced in patients with idiopathic venous thromboembolism treated with 1-year anticoagulant treatment compared with patients treated for 3 months.     

Deep-vein thrombosis is associated with large uterine fibroids

Pulmonary thromboembolism (PE) may occur upon a patient's first postoperative attempt of ambulation. PE is a serious complication, often leading to shock or sudden death. Reported rates of PE following gynecologic surgery are between 0.3% and 0.8%, while the incidence of postoperative deep-vein thrombosis (DVT), the major cause of PE, is between 17% and 20%. Therefore, effective preventive measures, such as preoperative assessment for asymptomatic DVT, should be considered. It is well known that DVT and/or PE are associated with large uterine fibroids, the common, benign tumor of myometrium. Here, to establish the statistical relationship between DVT risk and uterine fibroid size/weight, we assessed the preoperative DVT rate with respect to three possible risk factors: age, obesity level, and uterine size/weight. A total of 361 patients with uterine fibroids undergoing hysterectomy between July, 2003 and December, 2009 were enrolled. All patients were evaluated for preoperative DVT; the results were stratified for statistical comparison by patient age, BMI, and uterine weight. There was no statistical difference in the DVT rate for patients stratified by age (below age 45 years or older) or BMI (below 25 or higher). By contrast, the rate of DVT was significantly higher for patients with uterine weights of 1,000 gm or more (11.5% [7/61]) compared with weights below 1,000 gm (3.0% [9/300]). None of the patients studied developed PE. In conclusion, the incidence of DVT is significantly higher in cases where uterine weight is 1,000 gm or more (ie, adult head size on pelvic examination).     

Extended prophylaxis with bemiparin for the prevention of venous thromboembolism after abdominal or pelvic surgery for cancer: the CANBESURE randomized study

Summary. Background: There is not enough clinical evidence to make a strong recommendation on the optimal duration of thromboprophylaxis using low‐molecular weight heparins (LMWH) in patients undergoing major cancer surgery. Patients and methods: CANBESURE is a randomized, double‐blind study which enrolled patients admitted for abdominal or pelvic surgery for cancer. They received 3500 IU of bemiparin subcutaneously once daily for 8 days and were then randomized to receive either bemiparin or placebo for 20 additional days. Bilateral venography was performed after 20 days and evaluated blinded. The primary efficacy outcome was the composite of deep vein thrombosis (DVT), non‐fatal pulmonary embolism (PE) and all‐cause mortality at the end of double‐blind period. Major venous thromboembolism (proximal deep‐vein thrombosis, non‐fatal pulmonary embolism and venous thromboembolism‐related deaths) was also evaluated. The primary safety outcome was major bleeding. Results: Six hundred and twenty‐five and 488 patients were included in the safety and main efficacy analyzes, respectively. The primary efficacy outcome occurred in 25 out of 248 patients (10.1%) in the bemiparin group and 32 out of 240 (13.3%) in the placebo group (relative risk reduction 24.4%; 95% CI: ?23.7–53.8%; P = 0.26). At the end of double‐blind period, major venous thromboembolism occurred in 2 (0.8%) and 11 (4.6%) patients, respectively (relative risk reduction 82.4%; 95% CI: 21.5–96.1%; P = 0.010). No significant difference was found in major bleedings. Conclusions: Four weeks compared with 1 week of prophylaxis with bemiparin after abdominal or pelvic cancer surgery did not significantly reduce the primary efficacy outcome, but decreased major venous thromboembolism (VTE) without increasing hemorrhagic complications.     

Does the clinical presentation and extent of venous thrombosis predict likelihood and type of recurrence? A patient‐level meta‐analysis

Summary. Aim: To determine if the mode of presentation of venous thromboembolism (VTE), as deep vein thrombosis (DVT) or pulmonary embolism (PE), predicts the likelihood and type of recurrence. Methods: We carried out a patient‐level meta‐analysis of seven prospective studies in patients with a first VTE who were followed after anticoagulation was stopped. We used Kaplan‐Meier analysis to determine the cumulative incidence of recurrent VTE according to mode of presentation, and multivariable Cox regression to calculate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for mode of and extent of DVT as potential risk factors for recurrence. Results: The 5‐year cumulative rate of recurrent VTE in 2554 patients was 22.6%. In 869 (36.1%) patients with PE, the 5‐year rate of any recurrence (DVT or PE) was 22.0%, and recurrence as PE was 10.6%. In 1365 patients with proximal DVT, the 5‐year recurrence rate was 26.4%, and recurrence with PE was 3.6%. The risk of recurrence as PE was 3.1‐fold greater in patients presenting with symptomatic PE than in patients with proximal DVT (HR, 3.1; 95% CI, 1.9–5.1). Patients with proximal DVT had a 4.8‐fold higher cumulative recurrence rate than those with distal DVT (HR, 4.8; 95% CI, 2.1–11.0). Conclusion: Whilst DVT and PE are manifestations of the same disease, the phenotypic expression is predetermined. Patients presenting with PE are three times more likely to suffer recurrence as PE than patients presenting with DVT. Patients presenting with calf DVT are at low risk of recurrence and at low risk of recurrence as PE.     

Tinzaparin in outpatients with pulmonary embolism or deep vein thrombosis

BACKGROUND: The low-molecular-weight heparins (LMWHs) have been shown to be effective in the outpatient treatment of deep vein thrombosis (DVT). Data regarding outpatient use of any LMWH in pulmonary embolism (PE) or tinzaparin in DVT while transitioning therapy to a vitamin K antagonist are limited. OBJECTIVE: To determine the safety and efficacy of tinzaparin in patients with either DVT or PE being transitioned to warfarin during LMWH therapy in the outpatient setting. METHODS: All patients who were treated with at least one outpatient dose of tinzaparin for venous thromboembolism (VTE) were identified. Charts of all patients followed within the University of California Davis healthcare system were reviewed. The incidence of bleeding and recurrent thromboembolism over a minimum of the first 4 weeks to a maximum of 12 weeks after initiating anticoagulation was assessed. RESULTS: A total of 178 patients with acute VTE were treated with tinzaparin, and outcomes could be determined in 140 cases. Forty-seven percent of these patients had objectively documented PE. Only one (0.7%) case of recurrent VTE was observed. Major bleeding was documented in 5 (3.6%) and minor bleeding in 8 (5.8%) patients. Two bleeding events, both major, occurred during tinzaparin therapy. CONCLUSIONS: Outpatient use of tinzaparin during transition to warfarin therapy in the treatment of VTE, including PE, appears to be feasible in patients who are judged candidates for home therapy.     

Association between asymptomatic deep vein thrombosis detected by venography and symptomatic venous thromboembolism in patients undergoing elective hip or knee surgery

BACKGROUND: Venography is commonly used to compare the efficacy of different thromboprophylaxis strategies for preventing deep vein thrombosis (DVT) in patients undergoing total hip replacement (THR) or total knee replacement (TKR). METHODS: We explored the relation between asymptomatic DVT and symptomatic venous thromboembolism (VTE) in patients undergoing THR or TKR treated with standard doses of enoxaparin (30 mg b.i.d. or 40 mg o.d.) by comparing the incidence of asymptomatic DVT in venographic studies with the incidence of symptomatic VTE in studies where venography was not performed. RESULTS: In 10 venographic studies involving 5796 patients, the incidence of asymptomatic DVT after THR was 13.2% [95% CI, 12.2-14.2%] and after TKR was 38.1% (95% CI, 35.5-40.8%). In two studies involving 3500 patients who did not undergo venography, the 90-day incidence of symptomatic VTE after THR was 2.7% (95% CI, 2.1-3.4%) and after TKR was 1.8% (95% CI, 0.9-2.7%). For every symptomatic VTE in THR studies where venography was not performed there were five asymptomatic DVTs in the venographic studies; for TKR, the ratio was 1:21. The incidence of asymptomatic DVT and the symptomatic VTE/asymptomatic DVT ratio was influenced by the venogram reading committee (Gothenburg vs. Hamilton: total DVT after THR, 19.5% vs. 8.7%, P < 0.0001; for TKR, 42.7% vs. 27.2%, P < 0.0001). CONCLUSIONS: Comparisons across trials show a consistent relation between asymptomatic venographic DVT in patients undergoing elective THR or TKR surgery and symptomatic VTE in patients not undergoing venography. Differences exist in the strength of the relation depending on the type of surgery and the venogram reading committee.     

Venous thromboembolism in pregnancy

The risk of venous thromboembolism is increased during pregnancy. Although the absolute overall risk of deep venous thrombosis (DVT) or pulmonary embolism (PE) in pregnancy is low, clinicians are highly vigilant to the development of this disease in pregnancy because of the severe consequences to both mother and child if this condition is not diagnosed, treated and prevented. Although prompt recognition and diagnosis of DVT or PE is critical to reduce maternal morbidity, diagnosis of both DVT and PE currently relies on data from studies in nonpregnant patients. However, there are some recent studies offering new insights in this area. The development of venous thromboembolism during pregnancy is influenced by inherent patient risk factors, pregnancy-associated risk factors, and the mode and type of delivery. The degree of risk increase from these factors individually and in combination, to warrant routine thromboprophylaxis, weighed against bleeding risks, is not yet defined. With increased use of assisted reproductive techniques to achieve pregnancy, clinicians must also be vigilant to the development of venous thrombosis in early pregnancy, occurring in unusual sites such as the upper extremities.     

A phase II study of the oral factor Xa inhibitor LY517717 for the prevention of venous thromboembolism after hip or knee replacement

BACKGROUND: LY517717 is an oral direct inhibitor of activated factor X that is currently under clinical development. OBJECTIVES: The aims of this proof-of-concept study in patients undergoing total knee replacement (TKR) or total hip replacement (THR) were to determine whether LY517717 can safely reduce the risk of venous thromboembolism (VTE) and to identify at least one dose of LY517717 that is non-inferior to enoxaparin. METHODS: In a double-blind, parallel-arm, dose-ranging study, patients undergoing TKR or THR were randomly allocated to receive once-daily oral LY517717 (25, 50, 75, 100, 125 or 150 mg), started 6-8 h after wound closure, or s.c. enoxaparin, 40 mg, started in the evening before surgery. The primary efficacy endpoint was the composite of deep venous thrombosis (DVT), detected by mandatory bilateral venography performed at the end of the study treatment (between days 5 and 9), and objectively confirmed symptomatic DVT and/or pulmonary embolism (PE), occurring during the treatment period. The combination of major and minor bleeding was the primary safety endpoint. RESULTS: Five hundred and seven patients received at least one dose of LY517717 or enoxaparin (safety population). Three hundred and ninety-one patients had evaluable bilateral venography or experienced a clinical DVT and/or PE (primary efficacy population). LY517717 treatment resulted in a dose-dependent decrease in the incidence of thromboembolic events (P = 0.0001). The incidences of VTE with 100, 125, and 150 mg of LY517717 were 19%, 19% and 16%, respectively, compared to 21% with enoxaparin. The efficacies of 100-mg, 125-mg and 150-mg doses of LY517717 were non-inferior to that of enoxaparin according to prespecified criteria. Bleeding events were uncommon in both LY517717 and enoxaparin patients. CONCLUSIONS: Doses of 100, 125 and 150 mg of LY517717 are non-inferior to enoxaparin for the prevention of VTE after TKR or THR, and are associated with similar low rates of bleeding.     

脊柱外科手术后静脉血栓栓塞症自然发生率的临床研究

目的 分析脊柱手术后静脉血栓栓塞症（VTE）的自然发生率,探讨采取干预措施抗凝以预防VTE的必要性;结合文献,分析VTE的发生与手术方式、体位、时间等关系,指导临床改进相关环节.方法 2011年1月至2012年1月收治的接受脊柱手术患者168例,术前进行血常规、凝血指标及双下肢静脉彩超检查.术后复查双下肢静脉彩超.随访时间3个月.如果彩超怀疑深静脉血栓（DVT）,行下肢静脉造影确诊;如果高度怀疑肺栓塞（PE）形成,行肺血管造影确诊.统计患者资料及VTE例数.通过SPSS 11.0软件,利用x2检验、Mann-Whitney检验分析.结果 168例患者中确诊VTE1例,无PE病例.脊柱手术后VTE自然发生率为0.60％.尝试分析VTE阳性组与阴性组在性别、年龄、体重、手术时间、部位、入路、失血量、卧床时间等方面是否存在统计学差异.但由于VTE阳性例数少,随机性大,未能进行分析.结论 本次研究结果与文献报道类似,显示脊柱手术围手术期不采用抗凝措施下,VTE自然发生率较低;脊柱手术后对于无VTE症状以及不存在VTE危险因素的患者不需要行双下肢静脉彩超检查、血管造影检查以及常规抗凝处理.     

Venous thromboembolism in pregnancy

The risk of venous thromboembolism is increased during pregnancy. Although the absolute overall risk of deep venous thrombosis (DVT) or pulmonary embolism (PE) in pregnancy is low, clinicians are highly vigilant to the development of this disease in pregnancy because of the severe consequences to both mother and child if this condition is not diagnosed, treated and prevented. Although prompt recognition and diagnosis of DVT or PE is critical to reduce maternal morbidity, diagnosis of both DVT and PE currently relies on data from studies in nonpregnant patients. However, there are some recent studies offering new insights in this area. The development of venous thromboembolism during pregnancy is influenced by inherent patient risk factors, pregnancy-associated risk factors, and the mode and type of delivery. The degree of risk increase from these factors individually and in combination, to warrant routine thromboprophylaxis, weighed against bleeding risks, is not yet defined. With increased use of assisted reproductive techniques to achieve pregnancy, clinicians must also be vigilant to the development of venous thrombosis in early pregnancy, occurring in unusual sites such as the upper extremities.     

Type and location of venous thromboembolism in patients with factor V Leiden or prothrombin G20210A and in those with no thrombophilia

BACKGROUND: Patients with factor (F) V Leiden or the prothrombin G20210A polymorphism are at increased risk of developing deep vein thrombosis (DVT). On the other hand, the risk of developing pulmonary embolism (PE) appears to be low in carriers of FV Leiden, perhaps because of a lower tendency to develop iliofemoral DVT than non-carriers. For prothrombin G20210A, data are scanty and controversial. METHODS: The clinical manifestations (isolated DVT, DVT and PE, and isolated PE), the extension of DVT, and the presence of transient risk factors were retrospectively investigated in 115 patients with heterozygous FV Leiden, 87 with prothrombin G20210A and 200 with no thrombophilia marker. RESULTS: Isolated symptomatic PE was less prevalent in patients with FV Leiden (6%) than in those with prothrombin G20210A (21%) and no thrombophilia (23%) (P > 0.0001). The rate of distal DVT was higher in patients with no thrombophilia (16% vs. 7% for FV Leiden and 6% for prothrombin G20210A) (P = 0.02). No difference in the incidence of PE from distal and proximal DVT, the extension of proximal DVT and the type of transient risk factors for venous thromboembolism (VTE) was found in the three groups. Patients with prothrombin G20210A had a younger age at their first VTE (24 years, P < 0.0001) and a higher rate of DVT accompanying PE (P = 0.04) than those with FV Leiden or no thrombophilia. CONCLUSIONS: Carriers of prothrombin G20210A, unlike those of FV Leiden, have an increased risk of developing isolated PE. This difference was not explained by a different rate of distal DVT, extension of proximal DVT, or distribution of transient risk factors in the two groups. Patients with prothrombin G20210A have more severe clinical manifestations than those with FV Leiden or no thrombophilia.