Dissecting the rationale for thromboprophylaxis in challenging surgical cases.

Pulmonary embolism (PE) is a leading preventable cause of death in surgical patients, and rates of fatal PE are increasing. Individual assessment, to balance the risks of thrombosis and bleeding, is the key to providing appropriate prophylaxis. The risk assessment process includes use of evidence-based guidelines, literature published since the latest guidelines, large registries, and risk scoring systems together with clinical experience and judgment. Risk assessment is a dynamic process and needs to be updated both during the hospital stay and just prior to discharge since clinical events may change the level of risk. The final assessment may identify patients who require ongoing anticoagulant prophylaxis after discharge. The Caprini risk score is widely used in surgical patients and is a composite of the number of risk factors and their relative weights. The Caprini risk score set point for risk levels requiring anticoagulant prophylaxis varies depending on the type of surgical procedure, surgical population, and number of risk factors. Mandatory implementation of evidence-based care pathways is helpful in lowering PE-related mortality. This review presents several challenging cases, emphasizing the importance of employing all available assessment tools, including dynamic assessment of risk during hospitalization. Finally, the limitations of evidence-based guidelines in complex scenarios and the need to employ all available tools to properly protect very high-risk patients are emphasized.

The Thresholds of Caprini Score Associated With Increased Risk of Venous Thromboembolism Across Different Specialties: A Systematic Review.

OBJECTIVE: Estimation of the specific thresholds of the Caprini risk score (CRS) that are associated with the increased incidence of venous thromboembolism (VTE) across different specialties, including identifying the highest level of risk. BACKGROUND: Accurate risk assessment remains an important but often challenging aspect of VTE prophylaxis. One well-established risk assessment model is CRS, which has been validated in thousands of patients from many different medical and surgical specialties. METHODS: A search of MEDLINE and the Cochrane Library was performed in March 2022. Manuscripts that reported on (1) patients admitted to medical or surgical departments and (2) had their VTE risk assessed by CRS and (3) reported on the correlation between the score and VTE incidence, were included in the analysis. RESULTS: A total of 4562 references were identified, and the full text of 202 papers was assessed for eligibility. The correlation between CRS and VTE incidence was reported in 68 studies that enrolled 4,207,895 patients. In all specialties, a significant increase in VTE incidence was observed in patients with a CRS of ≥5. In most specialties thresholds of ≥7, ≥9, and ≥11 to 12 were associated with dramatically increased incidences of VTE. In COVID-19, cancer, trauma, vascular, general, head and neck, and thoracic surgery patients with ≥9 and ≥11 to 12 scores the VTE incidence was extremely high (ranging from 13% to 47%). CONCLUSION: The Caprini score is being used increasingly to predict VTE in many medical and surgical specialties. In most cases, the VTE risk for individual patients increases dramatically at a threshold CRS of 7 to 11.

Using the Caprini Risk Score to Increase VTE Awareness in the Community: The Know Your Score Project.

presented during the ISTH congress 2021Shetye, P., Gavankar, S, Saadaldin, H, et al, Using the Caprini Risk Score to Increase VTE Awareness in the Community. The Know Your Score Project. AS-ISTH-2021-02054, 2021.

A Prospective Study Evaluating Patterns of Responses to the Caprini Score to Prevent Venous Thromboembolism After Interventional Treatment for Varicose Veins.

BACKGROUND: Venous thromboembolism (VTE) is a critical complication of varicose vein treatments. The Caprini Score (CS) is an established tool to assess patients' VTE risks. One disadvantage is the number of questions required, some of them referring to a low incidence of disease, even lower in patients seeking an elective procedure. These elements take time and may result in filling errors if the CS is not filled out by a properly trained health professional. OBJECTIVE: To establish a response pattern in CS, with emphasis on questions that usually have a negative answer and propose a simpler adaptative digital version without changing the original structure of the tool. METHODS: two hundred and twenty-seven patients in the pre-surgical treatment of varicose veins were enrolled prospectively and submitted to the CS evaluation. RESULTS: The pattern of dichotomous responses could be divided arbitrarily into four subgroups considering the percentage of positive responses: none (11 items), less than 3% (13 items), between 3% and 20% (5 items), and more than 20% (8 items). Of the 12 CS questions related to illnesses that occurred in the last month, ten had had no responses, and 2 were less than 3%. CONCLUSION: There is a pattern in the CS responses of patients with an indication of surgical treatment of varicose veins. Many of the CS questions are not helpful in this scenario and may result in filling errors performed by untrained providers. An adaptative version of the CS might benefit varicose veins surgery VTE risk stratification.

Combined intermittent pneumatic leg compression and pharmacological prophylaxis for prevention of venous thromboembolism.

BACKGROUND: It is generally assumed by practitioners and guideline authors that combined modalities (methods of treatment) are more effective than single modalities in preventing venous thromboembolism (VTE), defined as deep vein thrombosis (DVT) or pulmonary embolism (PE), or both. This is the second update of the review first published in 2008. OBJECTIVES: The aim of this review was to assess the efficacy of combined intermittent pneumatic leg compression (IPC) and pharmacological prophylaxis compared to single modalities in preventing VTE. SEARCH METHODS: The Cochrane Vascular Information Specialist searched the Cochrane Vascular Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, and AMED databases, and World Health Organization International Clinical Trials Registry Platform and ClinicalTrials.gov trials registers to 18 January 2021. We searched the reference lists of relevant articles for additional studies.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) or controlled clinical trials (CCTs) of combined IPC and pharmacological interventions used to prevent VTE compared to either intervention individually. DATA COLLECTION AND ANALYSIS: We independently selected studies, applied Cochrane's risk of bias tool, and extracted data. We resolved disagreements by discussion. We performed fixed-effect model meta-analyses with odds ratios (ORs) and 95% confidence intervals (CIs). We used a random-effects model when there was heterogeneity. We assessed the certainty of the evidence using GRADE. The outcomes of interest were PE, DVT, bleeding and major bleeding. MAIN RESULTS: We included a total of 34 studies involving 14,931 participants, mainly undergoing surgery or admitted with trauma. Twenty-five studies were RCTs (12,672 participants) and nine were CCTs (2259 participants). Overall, the risk of bias was mostly unclear or high. We used GRADE to assess the certainty of the evidence and this was downgraded due to the risk of bias, imprecision or indirectness. The addition of pharmacological prophylaxis to IPC compared with IPC alone reduced the incidence of symptomatic PE from 1.34% (34/2530) in the IPC group to 0.65% (19/2932) in the combined group (OR 0.51, 95% CI 0.29 to 0.91; 19 studies, 5462 participants, low-certainty evidence). The incidence of DVT was 3.81% in the IPC group and 2.03% in the combined group showing a reduced incidence of DVT in favour of the combined group (OR 0.51, 95% CI 0.36 to 0.72; 18 studies, 5394 participants, low-certainty evidence). The addition of pharmacological prophylaxis to IPC, however, increased the risk of any bleeding compared to IPC alone: 0.95% (22/2304) in the IPC group and 5.88% (137/2330) in the combined group (OR 6.02, 95% CI 3.88 to 9.35; 13 studies, 4634 participants, very low-certainty evidence). Major bleeding followed a similar pattern: 0.34% (7/2054) in the IPC group compared to 2.21% (46/2079) in the combined group (OR 5.77, 95% CI 2.81 to 11.83; 12 studies, 4133 participants, very low-certainty evidence). Tests for subgroup differences between orthopaedic and non-orthopaedic surgery participants were not possible for PE incidence as no PE events were reported in the orthopaedic subgroup. No difference was detected between orthopaedic and non-orthopaedic surgery participants for DVT incidence (test for subgroup difference P = 0.19).  The use of combined IPC and pharmacological prophylaxis modalities compared with pharmacological prophylaxis alone reduced the incidence of PE from 1.84% (61/3318) in the pharmacological prophylaxis group to 0.91% (31/3419) in the combined group (OR 0.46, 95% CI 0.30 to 0.71; 15 studies, 6737 participants, low-certainty evidence). The incidence of DVT was 9.28% (288/3105) in the pharmacological prophylaxis group and 5.48% (167/3046) in the combined group (OR 0.38, 95% CI 0.21 to 0.70; 17 studies; 6151 participants, high-certainty evidence). Increased bleeding side effects were not observed for IPC when it was added to anticoagulation (any bleeding: OR 0.87, 95% CI 0.56 to 1.35, 6 studies, 1314 participants, very low-certainty evidence; major bleeding: OR 1.21, 95% CI 0.35 to 4.18, 5 studies, 908 participants, very low-certainty evidence). No difference was detected between the orthopaedic and non-orthopaedic surgery participants for PE incidence (test for subgroup difference P = 0.82) or for DVT incidence (test for subgroup difference P = 0.69). AUTHORS' CONCLUSIONS: Evidence suggests that combining IPC with pharmacological prophylaxis, compared to IPC alone reduces the incidence of both PE and DVT (low-certainty evidence). Combining IPC with pharmacological prophylaxis, compared to pharmacological prophylaxis alone, reduces the incidence of both PE (low-certainty evidence) and DVT (high-certainty evidence). We downgraded due to risk of bias in study methodology and imprecision. Very low-certainty evidence suggests that the addition of pharmacological prophylaxis to IPC increased the risk of bleeding compared to IPC alone, a side effect not observed when IPC is added to pharmacological prophylaxis (very low-certainty evidence), as expected for a physical method of thromboprophylaxis. The certainty of the evidence for bleeding was downgraded to very low due to risk of bias in study methodology, imprecision and indirectness. The results of this update agree with current guideline recommendations, which support the use of combined modalities in hospitalised people (limited to those with trauma or undergoing surgery) at risk of developing VTE. More studies on the role of combined modalities in VTE prevention are needed to provide evidence for specific patient groups and to increase our certainty in the evidence.

The original and modified Caprini score equally predicts venous thromboembolism in COVID-19 patients.

OBJECTIVE: The study aimed to validate the original Caprini score and its modifications considering coronavirus disease (COVID-19) as a severe prothrombotic condition in patients admitted to the hospital. METHODS: The relevant data were extracted from the electronic medical records with an implemented Caprini score and were retrospectively evaluated. The score was calculated twice: by the physician on admission and by the investigator at discharge (death). The final assessment considered additional risk factors that occurred during inpatient treatment. Besides the original Caprini score (a version of 2005), the modified version added the elevation of D-dimer and specific scores for COVID-19 as follows: two points for asymptomatic, three points for symptomatic, and five points for symptomatic infection with positive D-dimer. Cases were evaluated retrospectively. The primary end point was symptomatic venous thromboembolism (VTE) detected during inpatient treatment and confirmed by appropriate imaging testing or autopsy. The secondary end points included those observed during hospitalization (admission to the intensive care unit, a requirement for invasive mechanical ventilation, death, bleeding), and those assessed at 6-month follow-up (symptomatic VTE, bleeding, death). The association of eight different versions of the Caprini score with VTE events was evaluated. RESULTS: A total of 168 patients (83 males and 85 females at the age of 58.3 ± 12.7 years) were admitted to the hospital between April 30 and May 29, 2020, and were discharged or died to the time of data analysis. The original Caprini score varied between 2 and 12 (5.4 ± 1.8) at the admission and between 2 and 15 (5.9 ± 2.5) at discharge or death. The maximal score was observed with modification including specific COVID-19 points of 5 to 20 (10.0 ± 3.0). Patients received prophylactic (enoxaparin 40 mg once daily: 2.4%), intermediate (enoxaparin 80 mg once daily: 76.8%), or therapeutic (enoxaparin 1 mg/kg twice daily: 20.8%) anticoagulation. Despite this, symptomatic VTE was detected in 11 (6.5%) inpatients. Of the 168 individuals, 28 (16.7%) admitted to the intensive care unit, 8 (4.8%) required invasive mechanical ventilation, and 8 (4.8%) died. Clinically relevant nonmajor bleeding was detected in two (1.2%) cases. The Caprini score of all eight versions demonstrated a significant association with inpatient VTE frequency. The highest predictability was observed for the original scale when assessed at discharge (death). Only symptomatic VTE was reported after discharge with a cumulative incidence of 7.1%. This did not affect the predictability of the Caprini score. Extended antithrombotic treatment was prescribed to 49 (29%) patients with a cumulative incidence of bleeding of 1.8% at 6 months. CONCLUSIONS: The study identified a significant correlation between the Caprini score and the risk of VTE in patients with COVID-19. All models including specific COVID-19 scores showed equally high predictability, and use of the original Caprini score is appropriate for patients with COVID-19.

Comparison of a nonpneumatic device to four currently available intermittent pneumatic compression devices on common femoral blood flow dynamics.

OBJECTIVE: The purpose of the present study was to compare common femoral vein blood flow enhancement during external mechanical compression using the novel, nonpneumatic Recovery Force Health Movement and Compressions (MAC) System (Recovery Force USA, Fishers, Ind), and four currently available intermittent pneumatic compression devices. METHODS: The MAC device was compared with the Kendall SCD 700 (Cardinal Health, Dublin, Ohio), Arjo Huntleigh Flowtron ACS900 (Arjo, Malmö, Sweden), ActiveCare+S.F.T. (Zimmer Biomet, Warsaw, Ind), and Circul8 (Ortho8, Rocklin, Calif). Doppler ultrasound measurements for each device were directly obtained from the right common femoral vein by a registered vascular technologist. The peak flow velocity and the time taken to reach the peak were calculated. For the MAC system only, the subjects were asked to walk a minimum of 500 steps while wearing the system, which was then checked for slippage. Leg size measurements were obtained using the noncontact Sigvaris Legreader XT5 (Vialis Ortopedia, Turin, Italy). The MAC device is not yet commercially available, and the present study was a prequel to clinical studies of venous thromboembolism prevention. RESULTS: We recruited a broad range of 20 subjects who varied in age (mean ± standard deviation [SD], 50.5 ± 16.2 years), body mass index (mean ± SD, 26 ± 5.5 kg/m2), gender (male, 25%; female, 75%), and right calf circumference (mean ± SD, 37.2 ± 5.5 cm). The peak flow velocity compared with the baseline measurements was significantly greater for the Recovery Force Health MAC System for three (Kendall SCD 700, P = .02; ActiveCare+S.F.T., P = .003; Circul8, P < .001) of the four comparisons. Although the difference was not significant, the Arjo Huntleigh Flowtron ACS900 (SD, 3.4 cm/s) had more measurement variability in the peak flow velocity compared with baseline than did the MAC System (SD, 1.9 cm/s). The MAC had a significantly (P < .001) faster rise time to peak flow compared with the comparison devices. It was the only device to achieve the target peak flow velocity over baseline of at least three times in every body mass index group. Finally, the MAC System met the goal of <2.5 cm of movement after ambulation in 100% of the measurements, with 75% of the measurements showing no movement. CONCLUSIONS: The MAC System is a mobile device that remained in place during ambulation and provided more consistent external mechanical compression in the desired range compared with the other three devices included in the present study.

Timing and characteristics of venous thromboembolism after noncancer surgery.

BACKGROUND: Venous thromboembolism (VTE) is a major cause of morbidity and mortality postoperatively. The use of pharmacologic prophylaxis is effective in reducing the incidence of VTE. However, the prophylaxis is often discontinued at hospital discharge, especially for those with benign disease. The implications of this practice are not known. We assessed the data from a large, ongoing registry regarding the time course of VTE and outcomes after noncancer surgery. METHODS: We analyzed the RIETE (Computerized Registry on Venous Thromboembolism) registry, which includes data from consecutive patients with symptomatic confirmed VTE. In the present study, we focused on general surgical patients who had developed symptomatic postoperative VTE in the first 8 weeks after noncancer surgery. The main objective was to assess the interval between surgery and the occurrence of VTE. Additional variables included the clinical presentation associated with the event, the use of thrombosis prophylaxis, and unfavorable outcomes. RESULTS: The data from 3296 patients were analyzed. The median time from surgery to the detection of VTE was 16 days (interquartile range, 8-30 days). Of the VTE events, 77% were detected after the first postoperative week and 27% after 4 weeks. Overall, 43.9% of the patients with VTE had received pharmacologic prophylaxis after surgery for a median of 8 days (interquartile range, 5-14 days), and three quarters of the VTE events were detected after pharmacologic prophylaxis had been discontinued. Overall, 54% of the patients with VTE had presented with pulmonary embolism. For 15% of the patients, the clinical outcome was unfavorable, including 4% who had died within 90 days. CONCLUSIONS: The risk of VTE after noncancer general surgery remains high for ≤2 months. More than one half of the patients had presented with symptomatic PE as the VTE event, and 15% had had unfavorable outcomes. Only 44% of these patients had received pharmacologic prophylaxis for around 1 week.

Predictors of Bleeding in the Perioperative Anticoagulant Use for Surgery Evaluation Study.

Background In the PAUSE (Perioperative Anticoagulant Use for Surgery Evaluation) Study, a simple, standardized, perioperative interruption strategy was provided for patients with nonvalvular atrial fibrillation taking direct oral anticoagulants (DOACs). Our objective was to define the factors associated with perioperative bleeding. Methods and Results We analyzed bleeding as the composite of major and clinically relevant nonmajor bleeding. Putative predictors of bleeding, and preoperative DOAC level were prospectively collected during recruitment. We used stratified logistic regression models for analysis. All statistical analyses were performed in R version 3.6.0. There were 3007 patients requiring perioperative DOAC interruption. More than one third of the included patients underwent a high bleeding risk procedure. The 30-day rates of major and clinically relevant nonmajor bleeding were 3.02% in apixaban (n=1257), 2.84% in dabigatran (n=668), and 4.16% for rivaroxaban (n=1082). Multivariate analysis stratified by region found more bleeding for hypertension (odds ratio [OR], 1.79; 95% CI 1.07-2.99; P=0.027), and prior bleeding (OR, 1.71; 95% CI, 1.08-2.71; P=0.021). Surgical bleed risk classification (high- versus low-risk) as a predictor of bleeding was only significant in the univariate analysis. The prediction model for major and clinically relevant nonmajor bleeding had an area under the curve of 0.71, and the preoperative DOAC level did not improve the area under the curve of the model. Conclusions In patients treated with DOACs who required an elective surgery/procedure and were managed with standardized DOAC interruption and resumption, there we did not find reversible risk factors for bleeding, suggesting that adjustment of the PAUSE management protocol to mitigate against bleeding is not needed.

Clinical Validation of the Chinese Version of Patient Completed Caprini Risk Assessment Form.

To create and validate patient-completed Caprini risk score (CRS) tools for Chinese people. We revised Chinese patient-completed CRS form according to previously published studies. We prospectively recruited 70 internal medical patients and 70 surgical patients. The average age of these patients was 54.26 ± 15.29 years, 54.29% of them were male and 80% of them had education beyond high school. The study compared: (1) patient-completed CRS and physician-completed CRS; (2) the final value of physician-completed CRS (physician-completed CRS + body mass index) and CRS in the electronic medical record (EMR) system. Patient-completed CRS was 3.71 ± 3.63, patients spent 3.60 ± 1.24 minutes, 57.14% patients were at high-highest risk; physician-completed CRS was 3.84 ± 3.63, physicians spent 2.11 ± 1.13 minutes, 59.28% patients were at high-highest risk; the final value of physician-completed CRS was 4.12 ± 3.62, 63.58% patients were at high-highest risk; CRS value in the EMR system was 4.07 ± 3.58, 65% patients were at high-highest risk. There were strong positive correlations (P < .0001) between patient-completed CRS and physician-completed CRS (r = 0.978, κ = 0.76) and between the final value of physician-completed CRS and CRS in EMR (r = 0.994, κ = 0.97). This study successfully developed and validated a Chinese patient-completed CRS that we found can replace physician-completed CRS. This results in considerable time saving for physicians and this process should increase the percentage of patients having complete risk assessment when they are admitted to the hospital.

Evidence-Based Practical Guidance for the Antithrombotic Management in Patients With Coronavirus Disease (COVID-19) in 2020.

This practical guidance, endorsed by the Brazilian Society of Thrombosis and Hemostasis and The Brazilian Society of Angiology and Vascular Surgery, the International Union of Angiology and the European Venous Forum, aims to provide physicians with clear guidance, based on current best evidence-based data, on clinical strategies to manage antithrombotic strategies in patients with coronavirus disease 2019.

COVID-19 and Thrombotic or Thromboembolic Disease: Implications for Prevention, Antithrombotic Therapy, and Follow-Up: JACC State-of-the-Art Review.

Coronavirus disease-2019 (COVID-19), a viral respiratory illness caused by the severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), may predispose patients to thrombotic disease, both in the venous and arterial circulations, because of excessive inflammation, platelet activation, endothelial dysfunction, and stasis. In addition, many patients receiving antithrombotic therapy for thrombotic disease may develop COVID-19, which can have implications for choice, dosing, and laboratory monitoring of antithrombotic therapy. Moreover, during a time with much focus on COVID-19, it is critical to consider how to optimize the available technology to care for patients without COVID-19 who have thrombotic disease. Herein, the authors review the current understanding of the pathogenesis, epidemiology, management, and outcomes of patients with COVID-19 who develop venous or arterial thrombosis, of those with pre-existing thrombotic disease who develop COVID-19, or those who need prevention or care for their thrombotic disease during the COVID-19 pandemic.

Perioperative Management of Patients With Atrial Fibrillation Receiving a Direct Oral Anticoagulant.

IMPORTANCE: Patients with atrial fibrillation (AF) who use a direct oral anticoagulant (DOAC) and request elective surgery or procedure present a common clinical situation yet perioperative management is uncertain. OBJECTIVE: To investigate the safety of a standardized perioperative DOAC management strategy. DESIGN, SETTING, AND PARTICIPANTS: The Perioperative Anticoagulation Use for Surgery Evaluation (PAUSE) cohort study conducted at 23 clinical centers in Canada, the United States, and Europe enrolled and screened patients from August 1, 2014, through July 31, 2018. Participants (n = 3007) had AF; were 18 years of age or older; were long-term users of apixaban, dabigatran etexilate, or rivaroxaban; were scheduled for an elective surgery or procedure; and could adhere to the DOAC therapy interruption protocol. INTERVENTIONS: A simple standardized perioperative DOAC therapy interruption and resumption strategy based on DOAC pharmacokinetic properties, procedure-associated bleeding risk, and creatinine clearance levels. The DOAC regimens were omitted for 1 day before a low-bleeding-risk procedure and 2 days before a high-bleeding-risk procedure. The DOAC regimens were resumed 1 day after a low-bleeding-risk procedure and 2 to 3 days after a high-bleeding-risk procedure. Follow-up of patients occurred for 30 days after the operation. MAIN OUTCOMES AND MEASURES: Major bleeding and arterial thromboembolism (ischemic stroke, systemic embolism, and transient ischemic attack) and the proportion of patients with an undetectable or minimal residual anticoagulant level (<50 ng/mL) at the time of the procedure. RESULTS: The 3007 patients with AF (mean [SD] age of 72.5 [9.39] years; 1988 men [66.1%]) comprised 1257 (41.8%) in the apixaban cohort, 668 (22.2%) in the dabigatran cohort, and 1082 (36.0%) in the rivaroxaban cohort; 1007 patients (33.5%) had a high-bleeding-risk procedure. The 30-day postoperative rate of major bleeding was 1.35% (95% CI, 0%-2.00%) in the apixaban cohort, 0.90% (95% CI, 0%-1.73%) in the dabigatran cohort, and 1.85% (95% CI, 0%-2.65%) in the rivaroxaban cohort. The rate of arterial thromboembolism was 0.16% (95% CI, 0%-0.48%) in the apixaban cohort, 0.60% (95% CI, 0%-1.33%) in the dabigatran cohort, and 0.37% (95% CI, 0%-0.82%) in the rivaroxaban cohort. In patients with a high-bleeding-risk procedure, the rates of major bleeding were 2.96% (95% CI, 0%-4.68%) in the apixaban cohort and 2.95% (95% CI, 0%-4.76%) in the rivaroxaban cohort. CONCLUSIONS AND RELEVANCE: In this study, patients with AF who had DOAC therapy interruption for elective surgery or procedure, a perioperative management strategy without heparin bridging or coagulation function testing was associated with low rates of major bleeding and arterial thromboembolism.