Incidence of thrombotic complications in critically ill ICU patients with COVID-19

INTRODUCTION

COVID-19 may predispose to both venous and arterial thromboembolism due to excessive inflammation, hypoxia, immobilisation and diffuse intravascular coagulation. Reports on the incidence of thrombotic complications are however not available.

METHODS

We evaluated the incidence of the composite outcome of symptomatic acute pulmonary embolism (PE), deep-vein thrombosis, ischemic stroke, myocardial infarction or systemic arterial embolism in all COVID-19 patients admitted to the ICU of 2 Dutch university hospitals and 1 Dutch teaching hospital.

RESULTS

We studied 184 ICU patients with proven COVID-19 pneumonia of whom 23 died (13%), 22 were discharged alive (12%) and 139 (76%) were still on the ICU on April 5th 2020. All patients received at least standard doses thromboprophylaxis. The cumulative incidence of the composite outcome was 31% (95%CI 20-41), of which CTPA and/or ultrasonography confirmed VTE in 27% (95%CI 17-37%) and arterial thrombotic events in 3.7% (95%CI 0-8.2%). PE was the most frequent thrombotic complication (n = 25, 81%). Age (adjusted hazard ratio (aHR) 1.05/per year, 95%CI 1.004-1.01) and coagulopathy, defined as spontaneous prolongation of the prothrombin time > 3 s or activated partial thromboplastin time > 5 s (aHR 4.1, 95%CI 1.9-9.1), were independent predictors of thrombotic complications.

CONCLUSION

The 31% incidence of thrombotic complications in ICU patients with COVID-19 infections is remarkably high. Our findings reinforce the recommendation to strictly apply pharmacological thrombosis prophylaxis in all COVID-19 patients admitted to the ICU, and are strongly suggestive of increasing the prophylaxis towards high-prophylactic doses, even in the absence of randomized evidence.

Confirmation of the high cumulative incidence of thrombotic complications in critically ill ICU patients with COVID-19: An updated analysis

INTRODUCTION

We recently reported a high cumulative incidence of thrombotic complications in critically ill patients with COVID-19 admitted to the intensive care units (ICUs) of three Dutch hospitals. In answering questions raised regarding our study, we updated our database and repeated all analyses.

METHODS

We re-evaluated the incidence of the composite outcome of symptomatic acute pulmonary embolism (PE), deep-vein thrombosis, ischemic stroke, myocardial infarction and/or systemic arterial embolism in all COVID-19 patients admitted to the ICUs of 2 Dutch university hospitals and 1 Dutch teaching hospital from ICU admission to death, ICU discharge or April 22nd 2020, whichever came first.

RESULTS

We studied the same 184 ICU patients as reported on previously, of whom a total of 41 died (22%) and 78 were discharged alive (43%). The median follow-up duration increased from 7 to 14 days. All patients received pharmacological thromboprophylaxis. The cumulative incidence of the composite outcome, adjusted for competing risk of death, was 49% (95% confidence interval [CI] 41-57%). The majority of thrombotic events were PE (65/75; 87%). In the competing risk model, chronic anticoagulation therapy at admission was associated with a lower risk of the composite outcome (Hazard Ratio [HR] 0.29, 95%CI 0.091-0.92). Patients diagnosed with thrombotic complications were at higher risk of all-cause death (HR 5.4; 95%CI 2.4-12). Use of therapeutic anticoagulation was not associated with all-cause death (HR 0.79, 95%CI 0.35-1.8).

CONCLUSION

In this updated analysis, we confirm the very high cumulative incidence of thrombotic complications in critically ill patients with COVID-19 pneumonia.

The epidemiology of venous thromboembolism

Venous thromboembolism (VTE) is categorized by the U.S. Surgeon General as a major public health problem. VTE is relatively common and associated with reduced survival and substantial health-care costs, and recurs frequently. VTE is a complex (multifactorial) disease, involving interactions between acquired or inherited predispositions to thrombosis and VTE risk factors, including increasing patient age and obesity, hospitalization for surgery or acute illness, nursing-home confinement, active cancer, trauma or fracture, immobility or leg paresis, superficial vein thrombosis, and, in women, pregnancy and puerperium, oral contraception, and hormone therapy. Although independent VTE risk factors and predictors of VTE recurrence have been identified, and effective primary and secondary prophylaxis is available, the occurrence of VTE seems to be relatively constant, or even increasing.

Thromboembolism risk of COVID-19 is high and associated with a higher risk of mortality: A systematic review and meta-analysis

BACKGROUND

Studies have suggested that there is increased risk of thromboembolism (TE) associated with coronavirus disease 2019 (COVID-19). However, overall arterial and venous TE rates of COVID-19 and effect of TE on COVID-19 mortality is unknown.

METHODS

We did a systematic review and meta-analysis of studies evaluating TE in COVID-19. We searched PubMed, Cochrane, and Embase for studies published up to June 12, 2020. Random effects models were used to produce summary TE rates and odds ratios (OR) of mortality in COVID-19 patients with TE compared to those without TE. Heterogeneity was quantified with I 2 .

FINDINGS

Of 425 studies identified, 42 studies enrolling 8271 patients were included in the meta-analysis. Overall venous TE rate was 21% (95% CI:17-26%): ICU, 31% (95% CI: 23-39%). Overall deep vein thrombosis rate was 20% (95% CI: 13-28%): ICU, 28% (95% CI: 16-41%); postmortem, 35% (95% CI:15-57%). Overall pulmonary embolism rate was 13% (95% CI: 11-16%): ICU, 19% (95% CI:14-25%); postmortem, 22% (95% CI:16-28%). Overall arterial TE rate was 2% (95% CI: 1-4%): ICU, 5% (95%CI: 3-7%). Pooled mortality rate among patients with TE was 23% (95%CI:14-32%) and 13% (95% CI:6-22%) among patients without TE. The pooled odds of mortality were 74% higher among patients who developed TE compared to those who did not (OR, 1.74; 95%CI, 1.01-2.98; P = 0.04).

INTERPRETATION

TE rates of COVID-19 are high and associated with higher risk of death. Robust evidence from ongoing clinical trials is needed to determine the impact of thromboprophylaxis on TE and mortality risk of COVID-19.

FUNDING

None.

Incidence of and mortality from venous thromboembolism in a real-world population: the Q-VTE Study Cohort

BACKGROUND

The public health burden of venous thromboembolism, which includes deep vein thrombosis and pulmonary embolism, is not fully known, and contemporary incidence and mortality estimates are needed. We determined the incidence and case fatality of venous thromboembolism in a general population.

METHODS

Using the administrative health care databases of the Canadian province of Québec, we identified all incident cases of deep vein thrombosis or pulmonary embolism between 2000 and 2009 and classified them as definite or probable venous thromboembolism. We formed 2 patient cohorts, one with definite cases and the other including cases with definite or probable venous thromboembolism that were followed until December 31, 2009.

RESULTS

We identified 67,354 definite and 35,123 probable cases of venous thromboembolism. The age- and sex-adjusted incidence rates of definite or probable venous thromboembolism, deep vein thrombosis, and pulmonary embolism were 1.22 (95% confidence interval [CI], 1.22-1.23), 0.78 (95% CI, 0.77-0.79), and 0.45 (95% CI, 0.44-0.45) per 1000 person-years, respectively, while for definite venous thromboembolism it was 0.90 (95% CI, 0.89-0.90) per 1000 person-years. The 30-day and 1-year case-fatality rates after definite or probable venous thromboembolism were 10.6% (95% CI, 10.4-10.8) and 23.0% (95% CI, 22.8-23.3), respectively, and were slightly higher among definite cases. The 1-year survival rate was 0.47 (95% CI, 0.46-0.48) for cases with definite or probable venous thromboembolism and cancer, 0.93 (95% CI, 0.93-0.94) for cases with unprovoked venous thromboembolism, and 0.84 (95% CI, 0.83-0.84) for cases with venous thromboembolism secondary to a major risk factor. Similar survival rates were seen for cases with definite venous thromboembolism.

CONCLUSION

The risk of venous thromboembolism in the general population remains high, and mortality, especially in cancer patients with venous thromboembolism, is substantial.

Incidence of asymptomatic deep vein thrombosis in patients with COVID-19 pneumonia and elevated D-dimer levels

AIM

An increased risk of venous thromboembolism (VTE) in patients with COVID-19 pneumonia admitted to intensive care unit (ICU) has been reported. Whether COVID-19 increases the risk of VTE in non-ICU wards remains unknown. We aimed to evaluate the burden of asymptomatic deep vein thrombosis (DVT) in COVID-19 patients with elevated D-dimer levels.

METHOD

In this prospective study consecutive patients hospitalized in non-intensive care units with diagnosis of COVID-19 pneumonia and D-dimer > 1000 ng/ml were screened for asymptomatic DVT with complete compression doppler ultrasound (CCUS). The study was approved by the Institutional Ethics Committee.

RESULTS

The study comprised 156 patients (65.4% male). All but three patients received standard doses of thromboprophylaxis. Median days of hospitalization until CCUS was 9 (IQR 5-17). CCUS was positive for DVT in 23 patients (14.7%), of whom only one was proximal DVT. Seven patients (4.5%) had bilateral distal DVT. Patients with DVT had higher median D-dimer levels: 4527 (IQR 1925-9144) ng/ml vs 2050 (IQR 1428-3235) ng/ml; p < 0.001. D-dimer levels > 1570 ng/ml were associated with asymptomatic DVT (OR 9.1; CI 95% 1.1-70.1). D-dimer showed an acceptable discriminative capacity (area under the ROC curve 0.72, 95% CI 0.61-0.84).

CONCLUSION

In patients admitted with COVID-19 pneumonia and elevated D-dimer levels, the incidence of asymptomatic DVT is similar to that described in other series. Higher cut-off levels for D-dimer might be necessary for the diagnosis of DVT in COVID-19 patients.

Guidance for the treatment and prevention of obstetric-associated venous thromboembolism

Venous thromboembolism (VTE), which may manifest as pulmonary embolism (PE) or deep vein thrombosis (DVT), is a serious and potentially fatal condition. Treatment and prevention of obstetric-related VTE is complicated by the need to consider fetal, as well as maternal, wellbeing when making management decisions. Although absolute VTE rates in this population are low, obstetric-associated VTE is an important cause of maternal morbidity and mortality. This manuscript, initiated by the Anticoagulation Forum, provides practical clinical guidance on the prevention and treatment of obstetric-associated VTE based on existing guidelines and consensus expert opinion based on available literature where guidelines are lacking.

Guidance for the treatment of deep vein thrombosis and pulmonary embolism

This guidance document focuses on the diagnosis and treatment of venous thromboembolism (VTE). Efficient, cost effective diagnosis of VTE is facilitated by combining medical history and physical examination with pre-test probability models, D dimer testing and selective use of confirmatory imaging. Clinical prediction rules, biomarkers and imaging can be used to tailor therapy to disease severity. Anticoagulation options for acute VTE include unfractionated heparin, low molecular weight heparin, fondaparinux and the direct oral anticoagulants (DOACs). DOACs are as effective as conventional therapy with LMWH and vitamin K antagonists. Thrombolytic therapy is reserved for massive pulmonary embolism (PE) or extensive deep vein thrombosis (DVT). Inferior vena cava filters are reserved for patients with acute VTE and contraindications to anticoagulation. Retrievable filters are strongly preferred. The possibility of thoracic outlet syndrome and May-Thurner syndrome should be considered in patients with subclavian/axillary and left common iliac vein DVT, respectively in absence of identifiable triggers. The optimal duration of therapy is dictated by the presence of modifiable thrombotic risk factors. Long term anticoagulation should be considered in patients with unprovoked VTE as well as persistent prothrombotic risk factors such as cancer. Short-term therapy is sufficient for most patients with VTE associated with transient situational triggers such as major surgery. Biomarkers such as D dimer and risk assessment models such the Vienna risk prediction model offer the potential to customize VTE therapy for the individual patient. Insufficient data exist to support the integration of bleeding risk models into duration of therapy planning.

Secular Trends in Incidence and Mortality of Acute Venous Thromboembolism: The AB-VTE Population-Based Study

BACKGROUND

Venous thromboembolism is a major cause of morbidity and mortality, and comprehensive studies profiling the epidemiology and pattern of health services use are needed. In this study we provide contemporary estimates of venous thromboembolism incidence and case fatality over the past decade.

METHODS

We developed a population-based venous thromboembolism dataset by linking 6 administrative health databases in Alberta, Canada from April 1, 2002 to March 31, 2012. We defined acute symptomatic cases using a validated algorithm and used Poisson regression to model annual venous thromboembolism counts.

RESULTS

We identified 31,656 cases of acute symptomatic venous thromboembolism between April 1, 2002 and March 31, 2012. The age- and sex-adjusted incidence rate of venous thromboembolism was 1.38 (95% confidence interval [CI], 1.37-1.40) per 1000 person-years. For pulmonary embolism it was 0.38 (95% CI, 0.36-0.40) per 1000 person-years, and for deep vein thrombosis it was 1.0 (95% CI, 0.99-1.1) per 1000 person-years. The adjusted model showed no significant change in the incidence of venous thromboembolism during the study period. The 30-day case fatality rate of venous thromboembolism was 2.0% (95% CI, 1.89-2.21) and was almost doubled in patients with pulmonary embolism: 3.9% (95% CI, 3.50-4.33). The 1-year case fatality rate was 9.2% (95% CI, 8.88-9.52) for venous thromboembolism and 12.9% (95% CI, 12.2-13.6) for patients with pulmonary embolism. The case fatality rate increased with increasing subject age. The 1-year and 5-year survivals after first acute venous thromboembolism were similar in patients with unprovoked and provoked events. However, in patients with cancer-associated thrombosis, the 1-year and 5-year survival rate was 66% (95% CI, 64.71%-67.29%) and 46% (95% CI, 43.28%-48.72%), respectively.

CONCLUSION

The incidence of acute venous thromboembolism remained unchanged over a 10-year period. However, the case fatality of venous thromboembolism is substantial.

Peripherally Inserted Central Catheter-associated Deep Vein Thrombosis: A Narrative Review

BACKGROUND

Although common, little is known about factors associated with peripherally inserted central catheter-related deep vein thrombosis (PICC-DVT). To better guide clinicians, we performed a comprehensive literature review to summarize best practices for this condition.

METHODS

A systematic search of the literature for studies reporting epidemiology, diagnosis, treatment, and prevention of PICC-DVT was conducted. Algorithms for diagnosis and management were compiled using available evidence.

RESULTS

The incidence of PICC-DVT varied between 2% and 75% according to study population, testing modality and threshold for diagnosis. Studies evaluating the diagnostic utility of clinical symptoms suggested that these were neither sensitive nor specific for PICC-DVT; conversely, ultrasonography had excellent sensitivity and specificity and is recommended as the initial diagnostic test. Although more specific, contrast venography should be reserved for cases with high clinical probability and negative ultrasound findings. Centrally positioned, otherwise functional and clinically necessary PICCs need not be removed despite concomitant DVT. Anticoagulation with low-molecular-weight heparin or warfarin for at least 3 months represents the mainstay of treatment. The role of pharmacologic prophylaxis and screening for PICC-DVT in the absence of clinical symptoms is unclear at this time.

CONCLUSIONS

PICC-DVT is common, costly and morbid. Available evidence provides guidance for diagnosis, treatment and prevention of this condition.

Inflammation in venous thromboembolism: Cause or consequence?

Venous thromboembolism (VTE) which includes deep vein thrombosis (DVT) and pulmonary thromboembolism (PTE) is a moderately common disease especially in elderly population with high rate of recurrence and complications. Evidence is accumulating that VTE is not restricted to coagulation system and immune system appears to be involved in formation and resolution of thrombus. The present study was aimed at reviewing current evidences on immune system abnormalities such as alterations in cytokines, chemokines and immune cells. Also, current evidences suggest that; a, inflammation in general functions as a double-edged sword, b, inflammation can be both a cause and a consequence of VTE, and c, current anti-coagulation therapies are not well-equipped with the capacity to selectively inhibit inflammatory cells and pathways. Applying such inferences for selective pharmacological targeting of immune mediators in VTE and thereby for adoption of higher effective anti-thromboinflammatory strategies, either therapeutic or prophylactic, is henceforth to be considered as the line of research for future.

Thrombosis in vasculitis: from pathogenesis to treatment

In recent years, the relationship between inflammation and thrombosis has been deeply investigated and it is now clear that immune and coagulation systems are functionally interconnected.

Inflammation-induced thrombosis is by now considered a feature not only of autoimmune rheumatic diseases, but also of systemic vasculitides such as Behçet’s syndrome, ANCA-associated vasculitis or giant cells arteritis, especially during active disease.

These findings have important consequences in terms of management and treatment. Indeed, Behçet’syndrome requires immunosuppressive agents for vascular involvement rather than anticoagulation or antiplatelet therapy, and it is conceivable that also in ANCA-associated vasculitis or large vessel-vasculitis an aggressive anti-inflammatory treatment during active disease could reduce the risk of thrombotic events in early stages.

In this review we discuss thrombosis in vasculitides, especially in Behçet’s syndrome, ANCA-associated vasculitis and large-vessel vasculitis, and provide pathogenetic and clinical clues for the different specialists involved in the care of these patients.

Epidemiology of the post-thrombotic syndrome

The post thrombotic syndrome (PTS) refers to clinical manifestations of chronic venous insufficiency (CVI) following a deep-vein thrombosis (DVT). PTS is the most frequent complication of DVT, which develops in 20 to 50% of cases after proximal DVT and is severe in 5-10% of cases. The reported prevalence of PTS differs widely among studies because of differences in study populations, tools used to assess PTS, and time interval between acute DVT and PTS assessment. The two most important predictors of PTS are extensive proximal character of DVT and previous ipsilateral DVT. Other reported risk factors include pre-existing CVI, obesity, quality of anticoagulant treatment, older age and residual venous obstruction. Standardization of PTS assessment tools combined with the development of patient self-reported PTS scales are likely to constitute a breakthrough in research of the epidemiology of PTS, by allowing comparison between studies, meta-analyses and increasing the feasibility of longer follow-up of DVT patients. This should enable identification of patient populations at high risk of severe PTS, new predictors of PTS and targets for potential new treatments. In this perspective, identification of biomarkers that are predictive of PTS such as markers of inflammation is crucial in ongoing research.

Deep venous thrombosis in pregnancy: incidence, pathogenesis and endovascular management

Deep venous thrombosis (DVT) during pregnancy is associated with high mortality, morbidity, and costs. Pulmonary embolism (PE), its most feared complication, is the leading cause of maternal death in the developed world. DVT can also result in long-term complications that include postthrombotic syndrome (PTS) adding to its morbidity. Women are up to 5 times more likely to develop DVT when pregnant. The current standard of care for this condition is anticoagulation. This review discusses the epidemiology, pathogenesis, prophylaxis and diagnosis of DVT during pregnancy, and then focuses on endovascular treatment modalities. Inferior vena cava (IVC) filter placement and pharmacomechanical catheter directed thrombolysis (PCDT) in the pregnant patient are discussed, as well as patient selection criteria, and complications.

Oral rivaroxaban for Japanese patients with symptomatic venous thromboembolism - the J-EINSTEIN DVT and PE program

Background

The global EINSTEIN DVT and PE studies compared rivaroxaban (15 mg twice daily for 3 weeks followed by 20 mg once daily) with enoxaparin/vitamin K antagonist therapy and demonstrated non-inferiority for efficacy and superiority for major bleeding. Owing to differences in targeted anticoagulant intensities in Japan, Japanese patients were not enrolled into the global studies. Instead, a separate study of deep vein thrombosis (DVT) and/or pulmonary embolism (PE) in Japanese patients was conducted, which compared the Japanese standard of care with a reduced dose of rivaroxaban.

Methods

We conducted an open-label, randomized trial that compared 3, 6, or 12 months of oral rivaroxaban alone (10 mg twice daily or 15 mg twice daily for 3 weeks followed by 15 mg once daily) with activated partial thromboplastin time-adjusted intravenous unfractionated heparin (UFH) followed by warfarin (target international normalized ratio 2.0; range 1.5–2.5) in patients with acute, objectively confirmed symptomatic DVT and/or PE. Patients were assessed for the occurrence of symptomatic recurrent venous thromboembolic events or asymptomatic deterioration and bleeding.

Results

Eighty-one patients were assigned to rivaroxaban and 19 patients to UFH/warfarin. Three patients were excluded because of serious non-compliance issues. The composite of symptomatic venous thromboembolic events or asymptomatic deterioration occurred in 1 (1.4%) rivaroxaban patient and in 1 (5.3%) UFH/warfarin patient (absolute risk difference, 3.9% [95% confidence interval, -3.4–23.8]). No major bleeding occurred during study treatment. Clinically relevant non-major bleeding occurred in 6 (7.8%) patients in the rivaroxaban group and 1 (5.3%) patient in the UFH/warfarin group.

Conclusions

The findings of this study in Japanese patients with acute DVT and/or PE suggest a similar efficacy and safety profile with rivaroxaban and control treatment, consistent with that of the worldwide EINSTEIN DVT and PE program.

Trial registration

Clinicaltrials.gov: NCT01516840 and NCT01516814.

Electronic supplementary material

The online version of this article (doi:10.1186/s12959-015-0035-3) contains supplementary material, which is available to authorized users.

Venous Thromboembolism Complicated with COVID-19: What Do We Know So Far?

Coronavirus disease (COVID-19) is caused by the novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is responsible for the ongoing 2019-2020 pandemic. Venous thromboembolism (VTE), a frequent cardiovascular and/or respiratory complication among hospitalized patients, is one of the known sequelae of the illness. Hospitalized COVID-19 patients are often elderly, immobile, and show signs of coagulopathy. Therefore, it is reasonable to assume a high incidence of VTE among these patients. Presently, the incidence of VTE is estimated at around 25% of patients hospitalized in the intensive care unit for COVID-19 even under anticoagulant treatment at prophylactic doses. In this review, we discuss present knowledge of the topic, the unique challenges of diagnosis and treatment of VTE, as well as some of the potential mechanisms of increased risk for VTE during the illness. Understanding the true impact of VTE on patients with COVID-19 will potentially improve our ability to reach a timely diagnosis and initiate proper treatment, mitigating the risk for this susceptible population during a complicated disease.

The preoperative incidence of deep vein thrombosis (DVT) and its correlation with postoperative DVT in patients undergoing elective surgery for femoral neck fractures

INTRODUCTION

Data on the incidence of preoperative deep vein thrombosis (DVT) in patients, who are waiting for elective hip replacement for femoral neck fractures, are limited. Our primary goal was to determine the prevalence and risk factors of preoperative DVT in acute hip fracture patients awaiting hemi- or total hip arthroplasty using venography. The secondary objective was to find a possible relationship between preoperative and postoperative DVT.

METHODS

We enrolled 119 consecutive patients with subcapital femoral neck fracture, who were awaiting hip replacement at our institution. All of them received venography before and after surgery. We used univariate analysis and multivariate logistic regression analysis to identify the risk factors for preoperative DVT.

RESULTS

Of the patients, 35 patients (29.4 %) developed DVT in affected limbs before surgery. Both long duration of immobilization and increased level of D-dimer were associated with preoperative DVT independently. Intriguingly, 66.7 % of patients who were diagnosed with DVT after surgery had thrombus in the same location, as they did before surgery.

CONCLUSIONS

We identified the high incidence and risk factors of preoperative DVT in patients awaiting elective surgery for femoral neck fractures. The majority of patients diagnosed with DVT postoperatively had already had thrombus before surgery.

Acute Pulmonary Embolism: Focus on the Clinical Picture

Acute pulmonary embolism (APE) is characterized by numerous clinical manifestations which are the result of a complex interplay between different organs; the symptoms are therefore various and part of a complex clinical picture. For this reason, it may not be easy to make an immediate diagnosis. This is a comprehensive review of the literature on all the various clinical pictures in order to help physicians to promptly recognize this clinical condition, remembering that our leading role as cardiologists depends on and is influenced by our knowledge and working methods.

Systematic review of aspirin for thromboprophylaxis in modern elective total hip and knee arthroplasty

AIMS

There is uncertainty regarding the optimal means of thromboprophylaxis following total hip and knee arthroplasty (THA, TKA). This systematic review presents the evidence for acetylsalicylic acid (aspirin) as a thromboprophylactic agent in THA and TKA and compares it with other chemoprophylactic agents.

MATERIALS AND METHODS

A search of literature published between 2004 and 2014 was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A total of 13 studies were eligible for inclusion.

RESULTS

Evidence from one good quality randomised controlled trial (RCT) showed no difference in rates of venous thrombo-embolism (VTE) in patients given aspirin or low molecular weight heparin (LMWH) following TKA. There was insufficient evidence from trials with moderate to severe risk of bias being present to suggest aspirin is more or less effective than LMWH, warfarin or dabigatran for the prevention of VTE in TKA or THA. Compared with aspirin, rates of asymptomatic deep vein thrombosis (DVT) in TKA may be reduced with rivaroxaban but insufficient evidence exists to demonstrate an effect on incidence of symptomatic DVT. Compared with aspirin there is evidence of more wound complications following THA and TKA with dabigatran and in TKA with rivaroxaban. Some studies highlighted concerns over bleeding complications and efficacy of aspirin.

CONCLUSION

The results suggest aspirin may be considered a suitable alternative to other thromboprophylactic agents following THA and TKA. Further investigation is required to fully evaluate the safety and efficacy of aspirin. Cite this article: Bone Joint J 2016;98-B:1056-61.

The Association Between PICC Use and Venous Thromboembolism in Upper and Lower Extremities

BACKGROUND

Peripherally inserted central catheters are associated with upper-extremity deep vein thrombosis. Whether they also are associated with lower-extremity deep vein thrombosis or pulmonary embolism is unknown. We examined the risk of venous thromboembolism in deep veins of the arm, leg, and chest after peripherally inserted central catheter placement.

METHODS

We conducted a multicenter, retrospective cohort study of 76,242 hospitalized medical patients from 48 Michigan hospitals. Peripherally inserted central catheter presence, comorbidities, venous thrombosis risk factors, and thrombotic events within 90 days from hospital admission were ascertained by phone and record review. Cox proportional hazards models were fit to examine the association between peripherally inserted central catheter placement and 90-day hazard of upper- and lower-extremity deep vein thrombosis or pulmonary embolism, adjusting for patient-level characteristics and natural clustering within hospitals.

RESULTS

A total of 3790 patients received a peripherally inserted central catheter during hospitalization. From hospital admission to 90 days, 876 thromboembolic events (208 upper-extremity deep vein thromboses, 372 lower-extremity deep vein thromboses, and 296 pulmonary emboli) were identified. After risk adjustment, peripherally inserted central catheter use was independently associated with all-cause venous thromboembolism (hazard ratio [HR], 3.16; 95% confidence interval [CI], 2.59-3.85), upper-extremity deep vein thrombosis (HR, 10.49; 95% CI, 7.79-14.11), and lower-extremity deep vein thrombosis (HR, 1.48; 95% CI, 1.02-2.15). Peripherally inserted central catheter use was not associated with pulmonary embolism (HR, 1.34; 95% CI, 0.86-2.06). Results were robust to sensitivity analyses incorporating receipt of pharmacologic prophylaxis during hospitalization.

CONCLUSIONS

Peripherally inserted central catheter use is associated with upper- and lower-extremity deep vein thrombosis. Weighing the thrombotic risks conferred by peripherally inserted central catheters against clinical benefits seems necessary.

Meta-analysis and suggested guidelines for prevention of venous thromboembolism (VTE) in foot and ankle surgery

PURPOSE

To perform a meta-analysis investigating venous thromboembolism (VTE) following isolated foot and ankle surgery and propose guidelines for VTE prevention in this group of patients.

METHODS

Following a PRISMA compliant search, 372 papers were identified and meta-analysis performed on 22 papers using the Critical Appraisal Skills Programme and Centre for Evidence-Based Medicine level of evidence.

RESULTS

43,381 patients were clinically assessed for VTE and the incidence with and without chemoprophylaxis was 0.6% (95% CI 0.4-0.8%) and 1% (95% CI 0.2-1.7%), respectively. 1666 Patients were assessed radiologically and the incidence of VTE with and without chemoprophylaxis was 12.5% (95% CI 6.8-18.2%) and 10.5% (95% CI 5.0-15.9%), respectively. There was no significant difference in the rates of VTE with or without chemoprophylaxis whether assessed clinically or by radiological criteria. The risk of VTE in those patients with Achilles tendon rupture was greater with a clinical incidence of 7% (95% CI 5.5-8.5%) and radiological incidence of 35.3% (95% CI 26.4-44.3%).

CONCLUSION

Isolated foot and ankle surgery has a lower incidence of clinically apparent VTE when compared to general lower limb procedures, and this rate is not significantly reduced using low molecular weight heparin. The incidence of VTE following Achilles tendon rupture is high whether treated surgically or conservatively. With the exception of those with Achilles tendon rupture, routine use of chemical VTE prophylaxis is not justified in those undergoing isolated foot and ankle surgery, but patient-specific risk factors for VTE should be used to assess patients individually.

LEVEL OF EVIDENCE

II.

A prospective study of Rivaroxaban for central venous catheter associated upper extremity deep vein thrombosis in cancer patients (Catheter 2)

INTRODUCTION

Patients with cancer are at increased risk of thrombosis, particularly those with central venous catheter (CVC) placement, which may predispose to the development of upper extremity deep vein thrombosis (UEDVT). Standard treatment includes low molecular weight heparin (LMWH) or LMWH bridged to warfarin. The direct oral anticoagulants (DOACs) have become standard of care for uncomplicated venous thromboembolism (VTE), but research in patients with cancer is ongoing.

OBJECTIVES

To assess rivaroxaban monotherapy in patients with cancer who develop UEDVT due to CVC for preservation of line function, and safety outcomes of VTE recurrence, bleeding risk and death.

MATERIALS AND METHODS

Patients ≥18years of age with active malignancy and symptomatic proximal UEDVT with or without pulmonary embolism (PE), associated with a CVC, were eligible. Treatment included rivaroxaban 15mg oral twice daily for 3weeks, followed by 20mg oral daily for 9weeks. Patients were followed clinically for 12weeks to assess for line function, recurrent VTE and bleeding.

RESULTS

Seventy patients (47 women) were included, with mean age 54.1years. The most common malignancy was breast cancer (41%). Preservation of line function was 100% at 12weeks. The risk of recurrent VTE at 12weeks was 1.43%, with one episode of fatal PE. 9 patients (12.9%) experienced 11 total bleeding episodes.

CONCLUSIONS

Rivaroxaban showed promise in treating CVC-UEDVT in cancer patients, resulting in preserved line function. However, bleeding rates and a fatal pulmonary embolism on treatment are concerning safety outcomes necessitating further study before rivaroxaban can be recommended.

Venous thromboembolism incidence in hematologic malignancies

Venous thromboembolism (VTE) remains a major cause of morbidity and mortality in patients with cancer. Although some very well validated scores delineate the risk of VTE by cancer subtype and other risk factors, hematologic malignancies are underrepresented in these models. This subgroup represents a unique entity that undergoes therapy that can be thrombogenic. The overall risk of VTE in patients with leukemia depends on the use of L-asparaginase treatment, older age, comorbidities and central venous catheters. Patients with acute promyelocytic leukemia are at particularly high risk of VTE but also have an increased risk of bleeding. Patients with aggressive lymphomas have a high incidence of VTE, roughly 10%. Patients with multiple myeloma at highest risk of VTE are those receiving immunomodulatory agents such as thalidomide or lenalidomide. Allogeneic stem cell transplantation carries a risk of thrombosis, particularly in patients developing graft versus host disease. This review summarizes the incidence of VTE in leukemia, lymphoma, myeloma and stem cell transplantation and provides practical guidance for preventing and managing VTE in patients with hematologic malignancies.