Pharmacological Thromboprophylaxis Research Articles

Incidence of Symptomatic Venous Thromboembolism (VTE) in 8,885 Elective Total Hip Arthroplasty Patients Receiving Post-operative Aspirin VTE Prophylaxis.

Venous thromboembolism (VTE) is a potentially reducible cause of morbidity and mortality in patients undergoing elective hip arthroplasty surgery. The balance of post-operative VTE prophylaxis and risk of post-operative haemorrhage remains at the forefront of surgeon's mind. The National Institute for Health and Care Excellence (NICE) published updated guidelines in 2018 which recommend the use of both mechanical and pharmacological methods in patients undergoing elective total hip arthroplasty (THA). The aim of this study was to present the symptomatic VTE incidence in 8,885 patients who underwent THA between January 1998 and March 2018 with Aspirin as the primary agent for pharmacological thromboprophylaxis. Intermittent calf compression stockings are routinely used from the time of surgery until mobilization (usually the following day) with prophylactic doses of low molecular weight heparin (LMWH) during inpatient stay (from 2005 onwards) and then Aspirin 150mg once daily for six weeks on hospital discharge (or Aspirin only prior to 2005), with use of other therapies occasionally as required. Analysis of prospective data collection from consecutive patients at a single institution undergoing THA was performed with the incidence of symptomatic deep vein thrombosis (DVT) and pulmonary embolism (PE) occurring within six months of the index operation as the primary outcome measure. Ninety-day all-cause mortality of this cohort of patients was also analysed. 8,885 patients were reviewed. This included 7230 primary, 224 complex primary and 1431 revision cases. The overall incidence of symptomatic VTE after elective THA was 1.11% (99/8885) - with the incidence of symptomatic DVT of 0.59% (52/8885) and the incidence of symptomatic PE of 0.53% (47/8885). There was no significant difference (χ2 test, p=0.239) in the symptomatic VTE incidence between primary (1.20% - 89/7230), complex primary (0.89% - 2/224) and revision cases (0.70% - 10/1431). The 90-day all-cause mortality was 0.88% (78/8885). Cardiovascular and respiratory disease were the main causes of death following surgery. Only 0.03% of deaths (n= 3) within 90 days of index surgery were due to PE. There was no significant difference (p=0.327) in length of stay (and hence amount of pharmacologic prophylaxis with LMWH received by patients before commencement of Aspirin) with the average length of stay for those patients who did not suffer a VTE of 6.8 days compared with 7.6 days for those who did suffer a VTE. Our results support the use of aspirin as an effective form of prophylaxis against symptomatic VTE following THA in contradiction to NICE and American Academy of Orthopaedic Surgery (AAOS) recommendations. It is not associated with an increased incidence in symptomatic DVT, PE or death compared to other published studies. The fact that it is inexpensive, readily available, requires no monitoring and does not pose an increased risk of bleeding are other advantages of using aspirin for VTE prophylaxis.

Heterogeneous Treatment Effects of Therapeutic-Dose Heparin in Patients Hospitalized for COVID-19

Randomized clinical trials (RCTs) of therapeutic-dose heparin in patients hospitalized with COVID-19 produced conflicting results, possibly due to heterogeneity of treatment effect (HTE) across individuals. Better understanding of HTE could facilitate individualized clinical decision-making. To evaluate HTE of therapeutic-dose heparin for patients hospitalized for COVID-19 and to compare approaches to assessing HTE. Exploratory analysis of a multiplatform adaptive RCT of therapeutic-dose heparin vs usual care pharmacologic thromboprophylaxis in 3320 patients hospitalized for COVID-19 enrolled in North America, South America, Europe, Asia, and Australia between April 2020 and January 2021. Heterogeneity of treatment effect was assessed 3 ways: using (1) conventional subgroup analyses of baseline characteristics, (2) a multivariable outcome prediction model (risk-based approach), and (3) a multivariable causal forest model (effect-based approach). Analyses primarily used bayesian statistics, consistent with the original trial. Participants were randomized to therapeutic-dose heparin or usual care pharmacologic thromboprophylaxis. Organ support-free days, assigning a value of -1 to those who died in the hospital and the number of days free of cardiovascular or respiratory organ support up to day 21 for those who survived to hospital discharge; and hospital survival. Baseline demographic characteristics were similar between patients randomized to therapeutic-dose heparin or usual care (median age, 60 years; 38% female; 32% known non-White race; 45% Hispanic). In the overall multiplatform RCT population, therapeutic-dose heparin was not associated with an increase in organ support-free days (median value for the posterior distribution of the OR, 1.05; 95% credible interval, 0.91-1.22). In conventional subgroup analyses, the effect of therapeutic-dose heparin on organ support-free days differed between patients requiring organ support at baseline or not (median OR, 0.85 vs 1.30; posterior probability of difference in OR, 99.8%), between females and males (median OR, 0.87 vs 1.16; posterior probability of difference in OR, 96.4%), and between patients with lower body mass index (BMI <30) vs higher BMI groups (BMI ≥30; posterior probability of difference in ORs >90% for all comparisons). In risk-based analysis, patients at lowest risk of poor outcome had the highest propensity for benefit from heparin (lowest risk decile: posterior probability of OR >1, 92%) while those at highest risk were most likely to be harmed (highest risk decile: posterior probability of OR <1, 87%). In effect-based analysis, a subset of patients identified at high risk of harm (P = .05 for difference in treatment effect) tended to have high BMI and were more likely to require organ support at baseline. Among patients hospitalized for COVID-19, the effect of therapeutic-dose heparin was heterogeneous. In all 3 approaches to assessing HTE, heparin was more likely to be beneficial in those who were less severely ill at presentation or had lower BMI and more likely to be harmful in sicker patients and those with higher BMI. The findings illustrate the importance of considering HTE in the design and analysis of RCTs. ClinicalTrials.gov Identifiers: NCT02735707, NCT04505774, NCT04359277, NCT04372589.

The incidence of symptomatic venous thromboembolism following orthopaedic surgery at Bay of Plenty District Health Board.

To investigate the incidence of symptomatic venous thromboembolism (VTE) after orthopaedic surgery. We performed a retrospective cohort study investigating the incidence of symptomatic VTE within 90 days of orthopaedic surgery in the Bay of Plenty District Health Board (DHB). Risk factors and antithrombotic regimens were also reviewed. After 1,133 unilateral total hip joint replacements (THJRs), there were six VTEs (incidence 0.5%, 95% CI 0.2-1.1%), four deep vein thromboses (DVT) (0.4%, 0.1-0.9%) and three pulmonary emboli (PE) (0.3%, 0.1-0.8%). Following 898 unilateral total knee joint replacements (TKJRs), 18 patients developed VTEs (2.0%, 1.2-2.9%), five developed DVTs (0.6%, 0.2-1.3%) and 16 developed PEs (1.8%, 1.1-2.9%). There were five VTEs after 224 THJR revisions (2.2%, 1.0-5.1%), five VTEs after 110 TKJR revisions (4.5%, 2.0-10.2%) and 16 VTEs after 846 hip fracture surgeries (1.9%, 1.2-3.0%). VTE risk factors were ICU admission post operatively and having known coronary or cerebrovascular disease. Within 1 week of surgery, 38.5% (30/78) of VTEs were diagnosed and within 2 weeks 66.7% (52/78) were diagnosed. Aspirin was being taken by 44% (34/78) of VTE patients and 26% (19/78) were on more potent antithrombotics. VTE is a rare complication of orthopaedic surgery. The highest risk period is the initial 2 weeks after a procedure. VTE can develop despite pharmacological thromboprophylaxis.

Association of early mobility with the incidence of deep-vein thrombosis and mortality among critically ill patients: a post hoc analysis of PREVENT trial

BackgroundThis study assessed the mobility levels among critically ill patients and the association of early mobility with incident proximal lower-limb deep-vein thrombosis and 90-day mortality.MethodsThis was a post hoc analysis of the multicenter PREVENT trial, which evaluated adjunctive intermittent pneumatic compression in critically ill patients receiving pharmacologic thromboprophylaxis with an expected ICU stay ≥ 72 h and found no effect on the primary outcome of incident proximal lower-limb deep-vein thrombosis. Mobility levels were documented daily up to day 28 in the ICU using a tool with an 8-point ordinal scale. We categorized patients according to mobility levels within the first 3 ICU days into three groups: early mobility level 4–7 (at least active standing), 1–3 (passive transfer from bed to chair or active sitting), and 0 (passive range of motion). We evaluated the association of early mobility and incident lower-limb deep-vein thrombosis and 90-day mortality by Cox proportional models adjusting for randomization and other co-variables.ResultsOf 1708 patients, only 85 (5.0%) had early mobility level 4–7 and 356 (20.8%) level 1–3, while 1267 (74.2%) had early mobility level 0. Patients with early mobility levels 4–7 and 1–3 had less illness severity, femoral central venous catheters, and organ support compared to patients with mobility level 0. Incident proximal lower-limb deep-vein thrombosis occurred in 1/85 (1.3%) patients in the early mobility 4–7 group, 7/348 (2.0%) patients in mobility 1–3 group, and 50/1230 (4.1%) patients in mobility 0 group. Compared with early mobility group 0, mobility groups 4–7 and 1–3 were not associated with differences in incident proximal lower-limb deep-vein thrombosis (adjusted hazard ratio [aHR] 1.19, 95% confidence interval [CI] 0.16, 8.90; p = 0.87 and 0.91, 95% CI 0.39, 2.12; p = 0.83, respectively). However, early mobility groups 4–7 and 1–3 had lower 90-day mortality (aHR 0.47, 95% CI 0.22, 1.01; p = 0.052, and 0.43, 95% CI 0.30, 0.62; p < 0.0001, respectively).ConclusionsOnly a small proportion of critically ill patients with an expected ICU stay ≥ 72 h were mobilized early. Early mobility was associated with reduced mortality, but not with different incidence of deep-vein thrombosis. This association does not establish causality, and randomized controlled trials are required to assess whether and to what extent this association is modifiable.Trial registrationThe PREVENT trial is registered at ClinicalTrials.gov, ID: NCT02040103 (registered on 3 November 2013) and Current controlled trials, ID: ISRCTN44653506 (registered on 30 October 2013).

Decision-analysis modeling of effectiveness and cost-effectiveness of pharmacologic thromboprophylaxis for surgical inpatients using variable risk assessment models or other strategies

BackgroundSurgical inpatients are at a risk of venous thromboembolism (VTE), which can be life-threatening or result in chronic complications. Thromboprophylaxis reduces the VTE risk but incurs costs and may increase bleeding risk. Risk assessment models (RAMs) are currently used to target thromboprophylaxis at high-risk patients. ObjectivesTo determine the balance of cost, risk, and benefit for different thromboprophylaxis strategies in adult surgical inpatients, excluding patients who underwent major orthopedic surgery or were under critical care and pregnant women. MethodsDecision analytic modeling was performed to estimate the following outcomes for alternative thromboprophylaxis strategies: thromboprophylaxis usage; VTE incidence and treatment; major bleeding; chronic thromboembolic complications; and overall survival. Strategies compared were as follows: no thromboprophylaxis; thromboprophylaxis for all; and thromboprophylaxis given according to RAMs (Caprini and Pannucci). Thromboprophylaxis is assumed to be given for the duration of hospitalization. The model evaluates lifetime costs and quality-adjusted life-years (QALYs) within England’s health and social care services. ResultsThromboprophylaxis for all surgical inpatients had a 70% probability of being the most cost-effective strategy (at a £20 000 per QALY threshold). RAM-based prophylaxis would be the most cost-effective strategy if a RAM with a higher sensitivity (99.9%) were available for surgical inpatients. QALY gains were mainly due to reduced postthrombotic complications. The optimal strategy was sensitive to several other factors such as the risk of VTE, bleeding and postthrombotic syndrome, duration of prophylaxis, and patient age. ConclusionThromboprophylaxis for all eligible surgical inpatients seemed to be the most cost-effective strategy. Default recommendations for pharmacologic thromboprophylaxis, with the potential to opt-out, may be superior to a complex risk-based opt-in approach.

Prevalence of perioperative asymptomatic venous thromboses of the lower extremity in 30 consecutive patients undergoing transsphenoidal surgery for Cushing’s disease

Cushing´s disease is a rare endocrinological disorder which is caused by an adrenocorticotropic hormone secreting pituitary adenoma. The condition is associated with an increased risk for venous thromboembolism. While there exist reports on symptomatic venous thromboses complicating Cushing’s disease, the prevalence of incidental leg vein thromboses accompanying pituitary surgery for Cushing’s disease is yet unknown. 30 consecutive patients (9 male; age 25–77 years) with histologically confirmed Cushing’s disease underwent transsphenoidal adenomectomy between October 2018 and September 2019. All patients received perioperative pharmacological thromboprophylaxis. Whole leg compression ultrasound was performed within one week after surgery (median 2 days) to exclude leg vein thromboses (primary endpoint). Preoperative laboratory values including plasma cortisol and various coagulation parameters were evaluated as secondary outcome measures. A comparison was made between patients with and without thrombotic events (p value ≤ 0.05). A total of 2 out of 30 patients (6.7%; CI 0.8–24.1%) presented with asymptomatic perioperative deep vein thromboses of the lower legs. Thrombosis patients differed not significantly from their counterparts with respect to age, sex, and comorbidities, but preoperative morning plasma cortisol was significantly higher in patients with venous thromboses (421.0 ± 49.5 μg/l vs. 188.1 ± 78.2 μg/l; p = 0.01). Moreover, von Willebrand factor activity was markedly increased in one case (409.0%) compared to the mean value obtained from 28 patients without phlebothromboses (146.9 ± 60.7%; p < 0.01). Perioperative asymptomatic leg vein thrombosis can be found with the aid of compression ultrasound in a considerable proportion of patients undergoing transsphenoidal adenomectomy for Cushing’s disease despite the administration of pharmacological thromboprophylaxis.

Perioperative Management of Incidental Pulmonary Embolisms on Trauma CT Scans: A Narrative Review.

Unsuspected pulmonary embolism (PE) may be identified on an initial traumacomputed tomography (CT) scan. The clinical importance of these incidental PEs remains to be elucidated.In patients who require surgery, careful management is needed.We sought to investigate the optimal perioperative management of such patients, including the use of pharmacological and mechanical thromboprophylaxis, possible thrombolytic therapy, and inferior vena cava (IVC) filters. A literature search was conducted, and all relevant articles were identified, investigated, and included. Medical guidelines were also consulted where appropriate.Pharmacological thromboprophylaxis is the mainstay of preoperative treatment, and low-molecular-weight heparins, fondaparinux, and unfractionated heparin may all be used. It has been suggested that prophylaxis should be administered as soon as possible after trauma. Such agents may be contraindicated in patients with significant bleeding, and mechanical prophylaxis and inferior vena cava filters may be favoured in these patients. Therapeutic anticoagulation and thrombolytic therapies may be consideredbut are associated with an increased risk of haemorrhage. Delaying surgery might help to minimise the risk of recurrent venous thromboembolism, and any interruption of prophylaxis must be strategically planned. Recommendations for postoperative care include a continuation of prophylaxis and therapeutic anticoagulation, with follow-up clinical evaluation within six months. Incidental PE is a common finding on trauma CT scans. Although the clinical significance is unknown, careful management of the balance between anticoagulation and bleeding is needed, especially in trauma patients and even more so in trauma patients requiring surgery.

Right needle, right patient, right time? A national flash-mob audit of thromboprophylaxis in palliative care

BackgroundThe prevention of hospital associated thrombosis in palliative care remains controversial yet many countries recommend the documented risk assessment and where appropriate pharmacological prophylaxis of inpatients with advanced cancer. AimTo audit adherence to national guidelines which require hospitalised patients to be risk assessed and receive appropriate thromboprophylaxis. DesignA one day “flash-mob” audit across multiple clinical inpatient sites across the United Kingdom. Setting/participantsInpatients receiving palliative care within hospitals, hospices and specialist palliative care units across the United Kingdom. ResultsData were collected from 1125 patients (514 hospital and 611 hospice/specialist palliative care units). Appropriate thromboprophylaxis was observed in 90 % of hospital and 90 % hospice/specialist palliative care units. Documented risk assessment was only found in 79 % and 71 % of patient notes respectively. Pharmacological thromboprophylaxis was contraindicated in 88 % of hospice/specialist palliative care unit patients due to bleeding risk or receiving end-of-life care. Twenty-four percent of patients in hospital had contraindications due to receiving end of life care, bleeding risk and thrombocytopenia. Patients in hospice/specialist palliative care units were of poorer performance status prior to admission with a history of gradual deterioration. Hospitalised patients were more likely to have been admitted following an acute deterioration of previous good performance status. ConclusionThromboprophylaxis guidelines were followed correctly for the majority of patients. There were considerable differences in the demographics of patients according to place of admission. Patients admitted to hospice/specialist palliative care units were sicker and had more contraindications to prophylaxis than those admitted to hospital. Thromboprophylaxis focused research data conducted in hospices is unlikely to be applicable to the care of palliative care patients admitted acutely to hospital.

Effect of therapeutic dose anticoagulation vs prophylactic dose anticoagulation in reducing venous thromboembolism, arterial thrombosis or death events among hospitalized non-critically ill COVID19 pt

Abstract Funding Acknowledgements Type of funding sources: None. Title The Effect of Therapeutic Dose Anticoagulation Versus Prophylactic Dose Anticoagulation in Reducing Venous Thromboembolism (VTE), Arterial Thrombosis (ATE) or Death Events Among Hospitalized Non-critically Ill COVID-19 Patients: A Meta-analysis. Background Coagulopathy-associated thrombotic events, leading to venous and arterial thromboembolism are highly prevalent among COVID-19 patients. While pharmacologic thromboprophylaxis are the mainstays of treatment, the consideration for an escalated therapeutic dose anticoagulation in the non-critically ill remained a highly debated issue. Objectives This meta-analysis sought to evaluate whether therapeutic dose anticoagulation among hospitalized non-critically ill COVID-19 patients reduce the composite primary efficacy outcome (VTE, ATE or death), and the secondary outcomes of major bleeding risk and progression to intubation and mechanical ventilation compared to prophylactic dose anticoagulation. Methodology After extensive search, screening based on predefined inclusion and exclusion criteria and critical appraisal by 3 independent reviewers 3 eligible open label RTCs with a total of 1492 patients were included in the study. The event rates of the primary and secondary outcomes were assessed after 21-30 days of hospitalization. Results The Risk Ratio for VTE, ATE and death is higher in the prophylactic dose anticoagulation (RR 1.42; 95% CI 1.08-1.86), p-value &amp;lt;0.05) compared to therapeutic dose anticoagulation. The risk for major bleeding (RR 0.70; 95% CI 0.30-1.62, p-value &amp;gt;0.05) and progression to intubation and mechanical ventilation (RR of 1.13; 95% CI 0.93-1.38, p-value &amp;gt;0.05) were not significantly different between the dosing regimens. Conclusion Therapeutic-dose regimen among non-critically ill admitted COVID-19 patients conferred lower risk for the composite primary outcome of VTE, ATE and death with similar risk for bleeding compared to prophylactic dose regimen. Due to this outcome advantage, therapeutic-dose anticoagulation can be considered as initial regimen in the non-critically ill COVID-19 patients in the absence of contraindications.

Venous thromboembolism risk following temporary immobilisation after injury: evaluation of the Aberdeen VTE risk tool

BackgroundTemporary lower limb immobilisation following injury is a risk factor for symptomatic venous thromboembolism (VTE). Pharmacological thromboprophylaxis can mitigate this risk but it is unclear which patients benefit from this...

Thrombosis in hereditary hemorrhagic telangiectasia

Thrombosis in hereditary hemorrhagic telangiectasia

Effectiveness of Thromboprophylaxis Agents Following Hip Fracture: A Systematic Review and Network Meta-Analysis.

Multiple studies have compared different pharmacologic thromboprophylaxis agents after hip fracture surgery, including aspirin, unfractionated heparin (UFH), low-molecular-weight heparin (LMWH), direct oral anticoagulants (DOAC), and warfarin, resulting in variability in clinical practice. To guide clinical management, a systematic review and network meta-analysis (NMA), which enables the simultaneous assessment of the effects of multiple interventions for the same patient population, was performed. This study aimed to determine the comparative effectiveness of thromboprophylaxis in reducing venous thromboembolism (VTE) in patients with surgically treated hip fractures. The primary outcome was the effect of the treatment on the VTE rate, and the secondary outcome was the treatment effect on the bleeding rate. Relevant studies were identified by a systematic search of Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials (CENTRAL) from January 2000 to February 2022. Title, abstract, and full-text screening; data extraction; and risk-of-bias assessment were performed. All studies examining thromboprophylaxis interventions (DOAC, LMWH, UFH, aspirin, and warfarin) in patients with a surgically treated hip fracture were included. Bayesian NMA was performed, and dichotomous outcome data were pooled using the odds ratio. Interventions were ranked using the surface under the cumulative ranking curve (SUCRA) for each outcome. A total of 19 studies were included after the screening of 466 citations and 77 full-text articles. Of the included studies, 15 studies had a high overall risk of bias. The NMA of the VTE outcome included 19 studies, 49,409 participants, and 6 thromboprophylaxis interventions. The NMA of the bleeding outcome included 3 studies, 18,163 participants, and 3 interventions. The mean age ranged from 43.5 to 86.2 years among the included studies. No thromboprophylaxis intervention was statistically different from any other intervention in its effect on the VTE or bleeding rate in hip fracture patients. This NMA demonstrated that there was no difference between the thromboprophylaxis interventions in reducing VTE or bleeding rates in hip fracture patients. More robust randomized controlled trials are needed to determine the most effective thromboprophylaxis interventions for patients with hip fractures. Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Venous thromboembolism risk score during hospitalization in pregnancy: results of 10694 prospective evaluations in a clinical trial

ObjectivesHospitalization during pregnancy and childbirth increases the risk of Venous Thromboembolism Risk (VTE). This study applied a VTE risk score to all hospitalized pregnant women to ascertain its effectiveness in preventing maternal death from VTE until 3 months after discharge. MethodsIn this interventional study, patients were classified as low- or high-risk according to the VTE risk score (Clinics Hospital risk score). High-risk patients (score ≥ 3) were scheduled for pharmacological Thromboprophylaxis (TPX). Interaction analysis of the main risk factors was performed using Odds Ratio (OR) and Poisson regression with robust variance. ResultsThe data of 10694 cases (7212 patients) were analyzed; 1626 (15.2%, 1000 patients) and 9068 (84.8%, 6212 patients) cases were classified as high-risk (score ≥ 3) and low-risk (score < 3), respectively. The main risk factors (Odds Ratio, 95% Confidence Interval) for VTE were age ≥ 35 and < 40 years (1.6, 1.4–1.8), parity ≥ 3 (3.5, 3.0–4.0), age ≥ 40 years (4.8, 4.1–5.6), multiple pregnancies (2.1, 1.7–2.5), BMI ≥ 40 kg/m2 (5.1, 4.3–6.0), severe infection (4.1, 3.3–5.1), and cancer (12.3, 8.8–17.2). There were 10 cases of VTE: 7/1636 (0.4%) and 3/9068 (0.03%) in the high- and low-risk groups, respectively. No patient died of VTE. The intervention reduced the VTE risk by 87%; the number needed to treat was 3. ConclusionsThis VTE risk score was effective in preventing maternal deaths from VTE, with a low indication for TPX. Maternal age, multiparity, obesity, severe infections, multiple pregnancies, and cancer were the main risk factors for VTE.

Comparison of four risk assessment tools for postpartum pharmacologic thromboprophylaxis

Multiple risk assessment tools (RAT) exist to determine which patients should receive postpartum pharmacologic thromboprophylaxis but one model has not been shown to be superior than another. Our objective is to compare the ability of four RATs in identifying high-risk patients who require postpartum pharmacologic thromboprophylaxis. We conducted a retrospective chart review of postpartum venous thromboembolism (VTE) cases after delivery hospitalizations from October 2016 to September 2019 at two tertiary care Beaumont Hospitals. Postpartum VTE cases were identified through ICD-10 codes and verified as occurring within 125 days of delivery. Four RATs were retrospectively applied to the postpartum VTE cases to determine the proportion of patients that stratified as high risk to qualify for postpartum pharmacologic thromboprophylaxis. Out of 31,445 delivery hospitalizations, 48 postpartum VTE cases were identified for an incidence of 0.15%. The average number of days from delivery hospitalization to VTE diagnosis was 27.7 (+/- 28.8). Of the 48 cases, 23 underwent cesarean delivery (CD) and 25 underwent spontaneous vaginal delivery (SVD). The California Maternal Quality Care Collaborative (CMQCC) RAT stratified 41.7% of the VTE cases as high risk for postpartum VTE. The National Partnership of Maternal Safety (NPMS) consists of a modified Padua and Caprini RAT for SVD and CD respectively and classified 52.1% of cases as high risk. The Royal College of Obstetrics and Gynecology (RCOG) RAT stratified the most patients as high risk with 75%. The American College of Chest Physicians (ACCP) stratified 82.6% of post-CD patients as high risk, whereas NPMS and RCOG RATs stratified 100% as high risk. In this cohort, more patients developed a postpartum VTE after delivery hospitalization for SVD than compared to CD. Furthermore, the RATs performed poorly in the post-SVD subgroup when compared to the post-CD subgroup. Additional study is needed to optimize postpartum thromboprophylaxis protocols.

Evaluation of pharmacological prophylaxis for deep venous thrombosis in hospitalized patients with risk factors at the university teaching hospitals, Lusaka, Zambia

Background: Deep venous thrombosis is a common clinical problem accounting for high rates of morbidity and mortality. The existence of risk factors, which include trauma, venous stasis, and hypercoagulability, is linked to the occurrence of the condition. Objective of current study was to evaluate DVT risk factors and prophylaxis pattern of use for patients who were admitted at the University Teaching Hospitals in Lusaka, Zambia.Methods: A cross-sectional study was conducted using medical files for patients who were hospitalized at the University Teaching Hospitals in Lusaka, Zambia from May 2020 to June 2021. Two hundred and ninety-six patient files were reviewed, and the Caprini risk assessment model was used to stratify patients into DVT risk categories. Multilinear regression analysis was used to identify factors associated with DVT prophylaxis.Results: Of the 296 patient files that were sampled from ICU, medical, and surgical wards, 198 (66.9%) (&gt;2 caprini score) were eligible for DVT prophylaxis, but only 77 (38.9%) of these eligible patients received prophylaxis. The number of eligible patients for DVT prophylaxis per department was as follows; ICU 50 (100%), Medical 71 (57.7%) and Surgery 77 (62.6%) wards. However, DVT prophylaxis was given to 21 (42%), 33 (46.5%), and 23 (29.9%) patients from the ICU, medical, and surgery, respectively. Enoxaparin was the most commonly used anticoagulant for Venous thromboembolism (VTE) prophylaxis with a mean dose of 60mg (SD±5). Across all departments, the most common predisposing risk factors for DVT were bed confinement for &gt;72 hours (167, 56.4%) and age of 41-60 years (118, 39.8%). In the adjusted model, swollen legs (AOR: 3.6, CI: 1.97, 6.57) and history of VTE (AOR: 21.3, CI: 9.87, 46.08) were significantly associated with a higher likelihood of DVT prophylaxis.Conclusions: Pharmacologic thromboprophylaxis is underutilized in patients in ICU, medical and surgical wards at the university teaching hospitals in Lusaka, Zambia. This study underscores the importance of implementing a DVT risk assessment technique for patients in ICU, medical and surgical wards and administering prophylaxis unless contraindicated.

Postoperative venous thromboembolism risk stratification in patients with uterine cancer

Uterine cancers are associated with a high risk for venous thromboembolisms. The American Society of Clinical Oncology practice guidelines recommend that all patients undergoing pelvic surgery for cancer should receive extended pharmacologic thromboprophylaxis with the duration being dependent on risk. However, risk stratification for patients with uterine cancer is not clearly defined. The Caprini score is the most widely used risk assessment model but it has been found to have limited use in the gynecologic oncology population. A modified Caprini score has been explored in other populations. The Khorana score is an additional risk assessment model that has not been studied in this context. Our objective was to evaluate the ability of a modified Caprini model and the Khorana score to risk stratify patients with uterine cancer for postoperative venous thromboembolisms within 90 days of surgery. Following institutional review board approval, a retrospective cohort study was performed, and all patients with uterine cancer who underwent a hysterectomy over a 4-year period were included. The Caprini and Khorana scores were calculated for each patient. The Caprini score cutoff for highest risk was evaluated at ≥7, ≥8, and ≥9 (modified Caprini) and the Khorana score cutoff was evaluated at ≥2 and ≥3. To determine the prognostic use of each score and other clinico-pathologic criteria related to the development of a venous thromboembolism, univariate analyses were performed using independent ttests, chi-square tests, or Fisher's exact tests; a multivariate analysis was performed using logistic regression. A total of 954 patients were included. The rate of venous thromboembolism development was 1.7% (16/954). A minimally invasive surgical approach was used in 90.5% (863/954) of patients. The mean Caprini score for patients with a venous thromboembolism was 10.3 compared with 8.1 for patients without a venous thromboembolism (95% confidence interval, 1.17-3.33; P<.0001). The mean Khorana score for the venous thromboembolism group was 2.4 vs 1.9 for those without (95% confidence interval, 0.04-0.82; P=.03). Both the Caprini and Khorana scores were found to be associated with venous thromboembolisms, but only a Caprini score with a cutoff of ≥8 or ≥9 was statistically significant (risk ratio, 31.25; 95% confidence interval, 1.88-519.49; risk ratio, 4.59; 95% confidence interval, 1.49-14.13, respectively), with high accuracy based on the area under the curve (0.75 and 0.68, respectively). Of the minimally invasive subgroup, 11.7% (101/863) of patients had same-day discharge with no postoperative thromboprophylaxis; none of these patients developed venous thromboembolisms. Despite extended prophylaxis among the laparotomy patients (30 days), the rate of venous thromboembolisms was more than 3 times that of the minimally invasive group (5.49% vs 1.7%). Advanced tumor stage and leukocytosis were noted to be independent risk factors for venous thromboembolisms. Our study suggests that using a modified Caprini score could help to identify the highest-risk patients who would benefit from prolonged thromboprophylaxis, could reduce the incidence of postoperative venous thromboembolisms, and could minimize the cost and harm of overtreatment. These findings need to be validated in a prospective manner, and further research is needed to determine the optimal duration of therapy.

Deep vein thrombosis after open hepatectomy or other major upper abdominal surgery in Taiwan: A prospective and cross-sectional study relevant to the issue of pharmacological thromboprophylaxis

Venous thromboembolism, including deep vein thrombosis (DVT) and pulmonary embolism (PE), is an important complication in patients who underwent open hepatic surgery as well as other major upper abdominal surgery. This study aims to investigate the occurrence of postoperative DVT without pharmacological thromboprophylaxis in such cohorts in Taiwan. This is a prospective, cross-sectional cohort study conducted from March 2010 to December 2011. Patients who underwent major upper abdominal surgery, including open hepatectomy, were enrolled. Color duplex compression ultrasonography (CUS) was used to detect DVT. Symptomatic PE was excluded if there were no suggestive respiratory symptoms or sudden death. Relevant clinicopathological and surgical information of each patient was collected and analyzed. 195 patients (118 male and 77 female) were enrolled, with a median age of 63.6 years. The majority (169/195, 88.7%) were treated for active malignancy. Totally 147 patients received open hepatectomy. Only one asymptomatic and distal postoperative DVT event was identified by CUS, which occurred on a 73-year-old female patient who received a left lateral segmental hepatectomy for removing the advanced hepatocellular carcinoma (pathologic stage, T3aN0M0). No cases of symptomatic PE or sudden death were observed. No correlation between DVT and precipitating factor was demonstrated in our cohort. Without pharmacological thromboprophylaxis, a low rate of postoperative DVT among patients undergoing open hepatectomy (0.7%, 1/147) or major upper abdominal surgery (0.5%, 1/195) in Taiwan was reported. A distinctively regional role of pharmacological thromboprophylaxis for hepatic surgery was also suggested by our data.

Thrombosis and anticoagulation: clinical issues of special importance to hematologists who practice in Asia

There are clinical issues of special importance and practice variation in the management of venous thromboembolism (VTE) and in the use of anticoagulants among hematologists who practice in Asia. In Asian-inherited thrombophilia, coagulation is disturbed due to loss-of-function mutations of protein S and protein C causing protein S and protein C deficiencies, whereas the gain-of-function factor V Leiden and prothrombin G20210A mutations are almost absent. Thrombophilia screening is not recommended in patients with VTE patients who have major provoking factors. However, it can be considered in unprovoked young patients with VTE who have a strong family history of VTE. Cancer is the most important acquired risk factor for VTE in Asians. Limited cancer screening at the initial presentation of unprovoked VTE is appropriate, especially in the elderly. Direct oral anticoagulants have been shown to have similar efficacy and reduce risk of major bleeding, including intracranial hemorrhage and bleeding requiring hospitalization, compared with warfarin. Most clinical trials evaluating therapies for treatment and prevention of VTE have included small numbers of Asian patients. Despite this lack of evidence, direct oral anticoagulants have been increasingly used in Asia for cancer-associated thrombosis. Individualized assessment of thrombotic and bleeding risks should be used for all hospitalized Asian patients when deciding on pharmacologic thromboprophylaxis. More research is needed to understand the factors that contribute to risks of VTE and anticoagulant-associated bleeding in Asian patients as these may differ from Western populations.

Standard dosing of enoxaparin versus unfractionated heparin in critically ill patient with COVID-19: a multicenter propensity-score matched study.

Thrombotic events are common in critically ill patients with COVID-19 and have been linked with COVID-19- induced hyperinflammatory state. In addition to anticoagulant effects, heparin and its derivatives have various anti-inflammatory and immunomodulatory properties that may affect patient outcomes. This study compared the effectiveness and safety of prophylactic standard-doses of enoxaparin andunfractionated heparin (UFH) in critically ill patients with COVID-19. METHODS: A multicenter, retrospective cohort study included critically ill adult patients with COVID-19 admitted to the ICU between March 2020 and July 2021. Patients were categorized into two groupsbased on the type of pharmacological VTE thromboprophylaxis given in fixed doses (Enoxaparin 40mg SQevery 24hours versus UFH 5000 Units SQevery 8hours) throughout their ICU stay.The primary endpoint was all cases of thrombosis. Other endpoints were considered secondary. Propensity score (PS)matching was used to match patients (1:1 ratio)between the two groups based on the predefined criteria. Multivariable logistic, Cox proportional hazards, and negative binomial regression analysis were used as appropriate. RESULTS: A total of 306 patients were eligible based on the eligibility criteria; 130 patients were included after PS matching (1:1 ratio). Patients who received UFH compared to enoxaparin had higher all thrombosis events at crude analysis (18.3% vs. 4.6%; p-value = 0.02 as well in logistic regression analysis (OR: 4.10 (1.05, 15.93); p-value = 0.04). Although there were no significant differences in all bleeding cases and major bleeding between the two groups (OR: 0.40 (0.07, 2.29); p-value = 0.31 and OR: 1.10 (0.14, 8.56); p-value = 0.93, respectively); however, blood transfusion requirement was higher in the UFH group but did not reach statistical significance (OR: 2.98 (0.85, 10.39); p-value = 0.09). The 30-day and in-hospital mortality were similar between the two groups at Cox hazards regression analysis. In contrast, hospital LOS was longer in the UFH group; however, it did not reach the statistically significantdifference (beta coefficient: 0.22; 95% CI: -0.03, 0.48; p-value = 0.09). Prophylactic enoxaparin use in critically ill patients with COVID-19 maysignificantly reduce all thrombosis cases with similar bleeding risk compared to UFH.

Real-World Management of Pharmacological Thromboprophylactic Strategies for COVID-19 Patients in Japan

Data on prophylactic anticoagulation are important in understanding the current issues, unmet needs, and optimal management of Japanese COVID-19 patients. This study aimed to investigate the clinical management strategies for prophylactic anticoagulation of COVID-19 patients in Japan. The CLOT-COVID study was a multicenter observational study that enrolled 2,894 consecutive hospitalized patients with COVID-19. The study population consisted of 2,889 patients (after excluding 5 patients with missing data); it was divided into 2 groups: patients with pharmacological thromboprophylaxis (n=1,240) and those without (n=1,649). Furthermore, we evaluated the 1,233 patients who received prophylactic anticoagulation-excluding 7 patients who could not be classified based on the intensity of their anticoagulants-who were then divided into 2 groups: patients receiving prophylactic anticoagulant doses (n=889) and therapeutic anticoagulant doses (n=344). The most common pharmacological thromboprophylaxis anticoagulant was unfractionated heparin (68.2%). The severity of COVID-19 at admission was a predictor of the implementation of pharmacological thromboprophylaxis in the multivariable analysis (moderate vs mild: OR: 16.6; 95% CI:13.2-21.0; P< 0.001, severe vs mild: OR: 342.6, 95%CI: 107.7-1090.2; P< 0.001). It was also a predictor of the usage of anticoagulants of therapeutic doses in the multivariable analysis (moderate vs mild: OR: 2.10; 95%CI: 1.46-3.02; P< 0.001, severe vs mild: OR: 5.96; 95%CI: 3.91-9.09; P<0.001). In the current real-world Japanese registry, pharmacological thromboprophylaxis, especially anticoagulants at therapeutic doses, was selectively implemented in COVID-19 patients with comorbidities and severe COVID-19 status at admission.