Venous thromboembolism prophylaxis may cause more harm than benefit: an evidence-based analysis of Canadian and international guidelines

Use of Thromboprophylaxis after Autologous Breast Reconstruction: A Cost-Effective Break-Even Analysis

BACKGROUND

Postoperative venous thromboembolism (VTE) is a major source of morbidity and mortality. The use of thromboprophylaxis among surgeons is not well studied in autologous breast reconstruction. The purpose of this study was to determine the rate of VTE in patients with breast cancer undergoing autologous breast reconstruction and to compare the cost-effectiveness of postoperative chemoprophylactic agents.

METHODS

The TriNetX National Health Research Network database was used to identify patients with breast cancer who underwent autologous breast reconstruction surgery between 2002 and 2022. The incidence of VTE within the first 30 days of surgery was calculated. A break-even analysis was performed to determine the break-even rate of VTE at which a chemoprophylactic agent would be cost-effective.

RESULTS

A cohort of 8221 patients was identified in this study. The rate of VTE was significantly higher in those without anticoagulation (4.0%) compared with those who received anticoagulation (2.6%) ( P = 0.0008). The break-even analysis for heparin and enoxaparin cost-effectiveness yielded absolute risk reductions of 0.73% and 1.63% for high-risk patients requiring 30 days of therapy and 0.20% and 0.43% for moderate-risk patients requiring 7 days of therapy, respectively.

CONCLUSIONS

The use of thromboprophylaxis significantly lowered the risk of VTE within 30 days after autologous breast reconstruction. Heparin appeared to be more cost-effective at preventing VTE compared with enoxaparin for both high- and moderate-risk patients. The presented model holds potential for other institution-specific variables that can be easily applied by plastic surgeons to determine the cost-effectiveness of any therapy.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Efficacy and Safety of Rivaroxaban for Extremely Aged Patients with Venous Thromboembolism: A Retrospective, Cross-Sectional Real-World Study

Background

Rivaroxaban, a non-vitamin K antagonist oral anticoagulant, has become widely used for the management of venous thromboembolism (VTE) in adult patients. However, few trials have explored the efficacy and safety of rivaroxaban in VTE patients over 80 years of age. This necessitates further real-world studies of rivaroxaban across elderly populations.

Methods

We performed a retrospective single center study involving extremely aged VTE sufferers treated with rivaroxaban. The sample comprised 121 patients newly initiated on rivaroxaban diagnosed between January 2018 and January 2020. Patients were followed up for no less than 2 years. The effectiveness outcome was the disappearance of thromboembolism. The safety outcome was the incidence of major bleeding events. Comorbidities and complications were recorded throughout the entire study.

Results

The efficacy outcome occurred in 114 of 121 patients (94.21%) and the safety outcome occurred in 12 of 121 patients (9.91%). Increased hemorrhages were observed in patients with infection (15.15% vs 7.80%), but no significant difference was observed due to limited sample size (P=0.3053). Patients with an age-adjusted Charlson comorbidity index score higher than 6 points exhibited higher bleeding rates (14.08% vs 4.00%; P=0.0676) and lower thrombus cure rates (88.73% vs 100%; P=0.0203).

Key conclusions

Patients with infection should be more careful of bleeding events during rivaroxaban therapy. An age-adjusted Charlson comorbidity index score higher than 6, which predicted poor survival, indicated inferior safety and efficacy of rivaroxaban.

Aim

To investigate the efficacy and safety of Rivaroxaban in an aged venous thromboembolism patient population under real-world conditions.

Correlation Between Statin Use and Symptomatic Venous Thromboembolism Incidence in Patients With Ankle Fracture: A Machine Learning Approach

BACKGROUND

Identifying factors that correlate with the incidence of venous thromboembolism (VTE) has the potential to improve VTE prevention and positively influence decision-making regarding prophylaxis. In this study, we aimed to investigate the correlation between statin consumption and the incidence of VTE in patients who sustained an ankle fracture.

METHODS

In this retrospective, case-controlled study, cases were those who developed VTE and controls were those who had no VTE, and the ratio was 1:4. Patients' demographics, history of hyperlipidemia, and reported statins use were obtained. A random forest classifier (RFC) model was used to predict whether statin consumers were at risk of VTE after ankle fracture regardless of VTE prophylaxis administration based on statin consumption, body mass index (BMI), age, and biological sex.

RESULTS

Of the 1175 patients with ankle fractures, 238 had confirmed VTE (case group), and 937 had no symptomatic VTE (control group; ratio 1:4). Fifty (21%) cases and 407 (43%) controls were on a statin. Statin users had a significantly lower incidence of VTE after ankle fracture, odds ratio (OR) = 0.35, 95% CI: 0.25, 0.49, P < .001. Our model showed an area under the receiving operator curve (AUROC) of 78%, a sensitivity of 73%, and a specificity of 83% in predicting the risk of VTE. The importance of the predictors of VTE, other than the use of statins (model importance = 0.1), were age (model importance of 0.72), BMI (model importance of 0.24), and biological sex (model importance of 0.02).

CONCLUSION

Statins were significantly associated with a lower rate of VTE in our population of patients who sustained an ankle fracture.

LEVELS OF EVIDENCE

3.

Obstetric venous thromboembolism: Evaluation of prophylactic approach based on risk scores, D-dimer levels, and ultrasonography findings in a tertiary hospital in Japan

AIM

Pulmonary embolism remains a leading cause of maternal mortality in developed countries despite developments in venous thromboembolism prophylaxis strategies. This study aimed to evaluate the effectiveness of our approach involving risk-scoring, D-dimer level assessment, and ultrasonography for obstetric venous thromboembolism.

METHODS

This retrospective cohort study included women who delivered at 22-41 weeks of gestation in The University of Tsukuba Hospital, Japan between January and December 2020. Venous thromboembolism risk (determined according to Japanese guidelines) and D-dimer levels were evaluated within 20 weeks of gestation, 30-34 weeks of gestation, and during the pre-delivery period (36 weeks of gestation or any time before preterm delivery). Compression and color Doppler ultrasonography for lower extremity deep vein thrombosis were performed if D-dimer levels were ≥3.2 μg/mL (for those undergoing cesarean delivery, 1.0 μg/mL).

RESULTS

Of 1026 women, 6 women had deep vein thrombosis during pregnancy and 1 during the puerperium period. Pulmonary embolism was not observed. The D-dimer screening result was positive for 8 women (2%) within 20 weeks of gestation (deep vein thrombosis was confirmed in 3 of them), 87 women (10%) (no deep vein thrombosis) at 30-34 weeks of gestation, and 367 women (36%) during the pre-delivery period (asymptomatic deep vein thrombosis in one). Based on the Japanese guidelines, 1%, 11%, 33%, and 55% of women had high, intermediate, low, and no postpartum risk factors, respectively.

CONCLUSIONS

Our approach appears useful for antenatal venous thromboembolism screening in the first trimester. For postpartum prophylaxis, more cost-effective strategies are needed.

Guideline No. 417: Prevention of Venous Thromboembolic Disease in Gynaecological Surgery

OBJECTIVE

The primary objective of this clinical practice guideline is to provide gynaecologists with an algorithm and evidence to guide the use of thromboprophylaxis in gynaecological surgery.

TARGET POPULATION

All patients undergoing gynaecological surgery for benign or malignant indications.

BENEFITS, HARMS, AND COSTS

The implementation of this guideline will benefit patients undergoing gynaecological surgery and provide physicians with a standard algorithm for the use of perioperative thromboprophylaxis.

EVIDENCE

The following search terms were entered into MEDLINE, Google Scholar, and Cochrane in 2017 and 2018: VTE, PE, DVT, thromboprophylaxis, gynaecological surgery, heparin, graduated compression stocking, intermittent pneumatic stocking, obesity, pediatrics, minimally invasive surgery, heparin induced thrombocytopenia, regional anesthesia). Articles included were randomized controlled trials, meta-analyses, systematic reviews, and observational studies. Additional publications were identified from the reference lists of these articles. There were no date limits, but search results were limited to English language articles only. Searches were updated and incorporated into the guideline up to September 2018.

VALIDATION METHODS

The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations).

INTENDED USERS

Gynaecologists and other members of the surgical team. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Systematic reviews of observational studies of Risk of Thrombosis and Bleeding in General and Gynecologic Surgery (ROTBIGGS): introduction and methodology

BACKGROUND

Venous thromboembolism (VTE) and bleeding are serious and potentially fatal complications of surgical procedures. Pharmacological thromboprophylaxis decreases the risk of VTE but increases the risk of major post-operative bleeding. The decision to use pharmacologic prophylaxis therefore represents a trade-off that critically depends on the incidence of VTE and bleeding in the absence of prophylaxis. These baseline risks vary widely between procedures, but their magnitude is uncertain. Systematic reviews addressing baseline risks are scarce, needed, and require innovations in methodology. Indeed, systematic summaries of these baseline risk estimates exist neither in general nor gynecologic surgery. We will fill this knowledge gap by performing a series of systematic reviews and meta-analyses of the procedure-specific and patient risk factor stratified risk estimates in general and gynecologic surgeries.

METHODS

We will perform comprehensive literature searches for observational studies in general and gynecologic surgery reporting symptomatic VTE or bleeding estimates. Pairs of methodologically trained reviewers will independently assess the studies for eligibility, evaluate the risk of bias by using an instrument developed for this review, and extract data. We will perform meta-analyses and modeling studies to adjust the reported risk estimates for the use of thromboprophylaxis and length of follow up. We will derive the estimates of risk from the median estimates of studies rated at the lowest risk of bias. The primary outcomes are the risk estimates of symptomatic VTE and major bleeding at 4 weeks post-operatively for each procedure stratified by patient risk factors. We will apply the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to rate evidence certainty.

DISCUSSION

This series of systematic reviews, modeling studies, and meta-analyses will inform clinicians and patients regarding the trade-off between VTE prevention and bleeding in general and gynecologic surgeries. Our work advances the standards in systematic reviews of surgical complications, including assessment of risk of bias, criteria for arriving at the best estimates of risk (including modeling of the timing of events and dealing with suboptimal data reporting), dealing with subgroups at higher and lower risk of bias, and use of the GRADE approach.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42021234119.

Is venous thromboembolism prophylaxis beneficial in upper limb major joint replacement surgery? A systematic review

BACKGROUND

Upper limb arthroplasty is an increasingly used treatment modality for end-stage joint disease of the shoulder, elbow and wrist. Whilst complications have been reported, the risk of venous thromboembolism has received less attention when compared to the lower limb. Guidance to aid clinical decision-making remains limited. This review aims to ascertain whether venous thromboembolism prophylaxis is beneficial after upper limb major joint replacement surgery.

METHODS

A systematic review was performed in April 2019, utilising EMBASE, MEDLINE, Cochrane and Google Scholar. All clinical studies reporting venous thromboembolism incidence and risk reduction (after prophylaxis) in upper limb joint replacement were included.

RESULTS

Twenty-four observational studies were identified. The reported incidence of venous thromboembolism ranged from 0.2% to 16% (weighted mean 0.68%) and 0.2% to 0.8% (weighted mean 0.49%) in shoulder and elbow arthroplasty, respectively. No records for wrist arthroplasty were found. In the literature, baseline venous thromboembolism risk of patients without an operation is reported as 0.5%.

DISCUSSION

There is a lack of good quality evidence regarding the risks and benefits of venous thromboembolism prophylaxis in upper limb major joint replacement surgery. We recommend further research, ideally formal randomised controlled trials to guide recommendations. Although venous thromboembolism is rare in upper limb surgery, surgeons should remain vigilant to this possibility.

Do Inpatients Receive Risk-Based Prophylactic Treatment for Thrombotic Events?

BACKGROUND

Current guidelines recommend risk-based use of prophylaxis for preventing medical inpatients from venous thromboembolism (VTE). Little is known about the current prescription practice, and even less whether differences between subspecialists like cardiologists, usually treating patients with thrombotic or thromboembolic diseases, and gastroenterologists, treating more patients with gastrointestinal bleeding complications, exist.

METHODS

We performed a retrospective chart review of patients on cardiology and gastroenterology wards of our university hospital. Patients with a clear indication for anticoagulation and contraindication against antithrombotic treatment were excluded. A total of 450 patients per specialty were included. Quantitative risk assessment models were used to determine the risk of a VTE (Padua Prediction Score (PPS), IMPROVE Score) and bleeding (IMPROVE-Bleeding and HAS-BLED Score).

RESULTS

The overall rate of VTE prophylaxis was high in both patient populations. Significant more low-risk cardiology compared to gastroenterology patients received drug-based prophylaxis. Furthermore, crucial discrepancies were found in the way individual patients would be classified based on PPS and IMPROVE Score. Finally, not the risk category but the length of hospital stay was best at predicting which patient received prophylaxis.

Mortality risk associated with venous thromboembolism: a systematic review and Bayesian meta-analysis

BACKGROUND

Venous thromboembolism is associated with increased mortality risk in some populations, but how frequently it is a direct cause of death is unclear. We used data from venous thromboembolism prevention trials to evaluate the causal effect of venous thromboembolism reduction on mortality.

METHODS

We did a systematic review and meta-analysis of randomised controlled trials (RCTs) evaluating venous thromboembolism prevention. We searched MEDLINE, Embase, PubMed, and Web of Science starting from Jan 1, 1993, to March 19, 2018. We included studies of patients who were at elevated risk of venous thromboembolism and were randomly assigned to either anticoagulant or antiplatelet therapy versus placebo or no treatment. We excluded studies with an active control agent (which might mitigate the lethality of venous thromboembolism) and those for which mortality data were unavailable. We modelled heterogeneity in a Bayesian framework, taking overall mortality as a primary endpoint, and pulmonary embolism, fatal pulmonary embolism, and major bleeding as secondary endpoints. We focused our analyses on studies reporting statistically significant effects of prevention on venous thromboembolism endpoints. We report treatment effects as median risk ratios (RRs), wherein a null effect equals 1, with 95% credible intervals (CrIs). This meta-analysis was registered with PROSPERO, CRD42018089697.

FINDINGS

From 4229 studies screened, we identified 86 eligible RCTs; 52, with data from over 70 000 patients, were positive, with significantly increased venous thromboembolism risk in patients in control groups versus treatment groups (RR 2·74, 95% CrI 2·32-3·31, p<0·0001). The meta-analysis established that the causal effect of venous thromboembolism prevention on mortality was null (control group mortality was 3391 [9·8%] of 34 537 patients; treatment group mortality was 3498 [9·8%] of 35 795 patients [RR 1·01, 95% CrI 0·97-1·06; p=0·58]) with low heterogeneity (τ 0·02, 95% CrI 0·00-0·07, p=0·89). Patients in control groups had more pulmonary embolism (RR 2·22, 95% CrI 1·78-2·89, p<0·0001) and fatal pulmonary embolism (1·58, 1·14-2·19, p=0·01), but less major bleeding (0·60, 0·47-0·75, p<0·0001) than those in treatment groups. A meta-analysis with the additional 34 negative studies yielded similar results for all endpoints except fatal pulmonary embolism, where evidence of an effect was weaker (1·42, 1·05-1·91, p=0·02).

INTERPRETATION

The perception that venous thromboembolism is a common cause of mortality should be revised considering the null effect of venous thromboembolism prevention on mortality. Our findings call into question the use of composite endpoints in venous thromboembolism-prevention trials and provide rationale for de-escalation trials.

FUNDING

None.

Routine surveillance for diagnosis of venous thromboembolism after pleurectomy for malignant pleural mesothelioma

OBJECTIVE

The purpose of this study was to determine the incidence of venous thromboembolism and utility of a routine surveillance program in patients undergoing surgery for mesothelioma.

METHODS

Patients undergoing pleurectomy from May 2016 to August 2018 were included. A standardized surveillance program to look for venous thromboembolism in this group included noninvasive studies every 7 days postoperatively or earlier if symptomatic. All patients received external pneumatic compression sleeves in addition to prophylactic heparin. If deep vein thrombosis or pulmonary embolus was discovered, heparin drip was initiated until conversion to therapeutic anticoagulation.

RESULTS

A total of 100 patients underwent pleurectomy for mesothelioma. Seven patients were found to have preoperative deep vein thrombosis, and as such only 93 patients were included for analysis. The median age of patients at surgery was 71 years (30-85 years). During the study, 30 patients (32%) developed evidence of thrombosis; 20 patients (22%) developed only deep vein thrombosis without embolism, 3 patients (3%) developed only pulmonary embolism, and 7 patients (7%) developed both deep vein thrombosis and pulmonary embolus. Of the 27 patients who developed deep vein thrombosis, 9 (33%) were asymptomatic at the time of diagnosis, and none of these developed a pulmonary embolus or other bleeding complications. There were 2 (2%) events of major postoperative bleeding related to therapeutic anticoagulation.

CONCLUSIONS

The incidence of venous thromboembolism is high (32%) among patients undergoing surveillance after pleurectomy for mesothelioma. Up to 33% of patients with deep vein thrombosis are asymptomatic at the time of diagnosis, and the incidence of complications related to anticoagulation is low. Routine surveillance may be useful to diagnose and treat deep vein thrombosis before it progresses to symptomatic or fatal pulmonary embolus.

Predictive Factors of Deep Vein Thrombosis in Gynecologic Cancer Survivors with Lower Extremity Edema: A Single-Center and Retrospective Study

This study was conducted to examine predictive factors of deep vein thrombosis (DVT) in gynecologic cancer survivors with lower extremity edema (LEE). In the current single-center, retrospective study, there was a total of 315 eligible patients, including 80 patients with DVT and 235 without DVT. They were therefore divided into two groups: the DVT group (n = 80) and the non-DVT group (n = 235). Then, baseline and clinical characteristics of the patients were compared between the two groups. In our study, distant organ metastasis, advanced stage, lymphadectomy, and amount of intraoperative blood loss had a positive predictive value for the occurrence of DVT in gynecologic cancer survivors presenting LEE. In conclusion, our results indicate that it is necessary to consider the possibility of LEE arising from DVT in gynecologic cancer survivors with advanced-stage cancer, distant organ metastasis, lymphadectomy, and intraoperative blood loss over 1500 mL.

Reassessment of venous thromboembolism and bleeding risk in medical patients receiving VTE prophylaxis

RATIONALE, AIMS, AND OBJECTIVES

The majority of hospitalized nonsurgical medical patients receive pharmacological prophylaxis for venous thromboembolism (VTE), and reassessment of changes in thrombosis and bleeding risk factors during hospital admission may represent an opportunity to discontinue unnecessary or unsafe therapy. The use of validated, clinically derived risk assessment models (RAMs) represents a shift towards an individualized, patient-centred approach to VTE prophylaxis. We are interested in using these tools to assess whether risk categories for VTE and bleeding change during admission and to assess whether such changes result in discontinuation of prophylaxis. Our primary objective was to determine whether VTE and bleed risk categories changed during the course of admission to warrant discontinuation of VTE prophylaxis, using the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) VTE and Bleed RAMs, respectively. Secondary objectives were to determine the number of patients whose risk categorizations for VTE and bleeding warranted discontinuation of VTE prophylaxis and to survey whether prophylaxis was continued or discontinued.

METHODS

A retrospective review was undertaken for a cross-sectional, randomly selected sample of patients who received VTE prophylaxis while admitted to medical wards in a collection of regional hospitals.

RESULTS

Of the 351 medical records reviewed, only eight patients (2.3%) changed their VTE risk category and six (1.7%) changed their bleed risk category to warrant discontinuation of VTE prophylaxis. Ninety patients (26%) were at high risk of VTE and low risk of bleed throughout admission, warranting continued VTE prophylaxis. The majority of patients remained at low risk of VTE throughout admission but remained on VTE prophylaxis until discharge.

CONCLUSIONS

Risk categories for VTE and bleeding for medical patients did not appreciably change throughout hospital admission. Use of VTE RAMs at admission and prior to initiation of therapy should reduce unnecessary prophylaxis in the majority of medical patients who are at low risk of VTE.

Risk factors for venous thromboembolism in individuals undergoing coronary artery bypass grafting

OBJECTIVE

Venous thromboembolism (VTE) can easily occur after coronary artery bypass grafting (CABG). We assessed the proportion of patients with a diagnosis of VTE after CABG and determined the associated risk factors and complications in these patients.

METHODS

We assessed all the patients included in the American College of Surgeons National Surgical Quality Improvement Program database from 2012 to 2015 who had undergone CABG. The demographic characteristics, surgical parameters, and complications were analyzed using single-factor and binary logistic regression analyses to identify the risk factors for VTE after CABG.

RESULTS

Overall, 8956 patients were identified. Postoperative VTE was found in 1.75% of these patients, with pulmonary embolism and deep vein thrombosis accounting for 0.61% and 1.28%, respectively; 0.15% of the patients had both conditions. The patients who had developed VTE had greater odds of being white and having an American Society of Anesthesiologists classification of ≥5. Multivariate analysis showed that a history of bleeding disorders, congestive heart failure, and operative time of ≥310 minutes were risk factors for the development of postoperative VTE. Patients with VTE had worse outcomes, including greater odds of returning to the operating room, hospitalization, unplanned reoperation, and readmission. The occurrence of VTE was associated with several postoperative complications, including emergency intubation, ventilator time >48 hours, pneumonia, urinary tract infection, peri- and postoperative transfusions, gradual kidney function reduction, acute kidney failure, cardiac arrest necessitating cardiopulmonary resuscitation, myocardial infarction, and septic shock.

CONCLUSIONS

The overall VTE rate after CABG has been low. However, the condition has been associated with worse 30-day postoperative outcomes and complications. The independent predictors of VTE development included a history of bleeding disorders, congestive heart failure in the 30 days before surgery, and operative time of ≥310 minutes. Understanding these risk factors should aid physicians in the decisions regarding prophylaxis and treatment.

Utilization of the Caprini score in conjunction with thrombodynamic testing reduces the number of unpredicted postoperative venous thromboembolism events in patients with colorectal cancer

BACKGROUND

The thrombodynamic test (TD) is a novel global test of hemostasis that allows to study the spatial-temporal characteristics of a clot formation in real time under conditions close to natural ones and demonstrates high sensitivity to detect the state of hypercoagulation. The main paraments of the test are the velocity of clot growth, clot's size, and clot density. The objective of this study was to compare the classic Caprini 2005 score and its modified version in association with the results of TD. The goal is to predict postoperative venous thromboembolism (VTE) in surgical patients undergoing surgery for colorectal cancer.

METHODS

This was a prospective observational clinical study involving 80 patients (33 men and 47 women; mean age, 73.9 ± 7.2 years) who underwent major (79 cases) or minor (1 case) surgery for colorectal cancer. Patients were at high risk for postoperative VTE (ie, a mean Caprini score of 9.9 ± 2.0) and received combined prophylaxis (ie, antiembolic compression stockings and enoxaparin 40 mg once daily) until discharge. Enoxaparin was administered at a fixed time of blood sampling for the TD test. Duplex ultrasound scan was performed to detect postoperative vein thrombosis before and 5 to 7 days after surgery.

RESULTS

Postoperative vein thrombosis was found in 21 of 80 patients (26.3%; 95% confidence interval, 17.9%-36.8%). Regression analysis and receiver operating characteristic (ROC) curve showed that Caprini scores significantly predicted VTE (P < .0001; area under the curve [AUC] = 0.839 ± 0.045). Analysis of ROC curve coordinates showed that a cutoff point of 11 scores had a sensitivity of 76.2% and a specificity of 74.6%. The results of the TD test showed significant hypercoagulation despite enoxaparin administration in patients with VTE. Regression analysis and ROC curves demonstrated that the following TD parameters had the greatest predictability for postoperative DVT: initial velocity of clot growth (Vin) and clot size (CS) measured at 12 hours after enoxaparin administration (AUC, 0.697 ± 0.063 and AUC, 0.790 ± 0.059, respectively), as well as Vin and CS measured 24 hours after the enoxaparin injection (S = 0.847 ± 0.059 and S = 0.803 ± 0.069, respectively). The cutoff points for VTE prediction at 12 and 24 hours seemed to be a Vin of greater than 62.5 and greater than 64.5 μm/minute (normal range, 35-56 μm/minute) as well as a CS of greater than 1351.5 and greater than 1333.5 μm (normal range, 800-1200 μm), respectively. Identified thresholds for TD parameters have been integrated into Caprini scores under the item "other congenital or acquired thrombophilia." The total Caprini scores were recalculated in patients where one or all TD parameters had exceeded the cutoff followed by reanalysis of the ROC curves. The best predictability was found for Caprini scores considering the elevation of all four TD parameters (AUC, 0.924 ± 0.029) with increased cutoff to a score of 12 with a sensitivity of 85.7% and a specificity of 81.4%. The use of cutoffs for the original and modified scores could be used to calculate the number of patients that were under cutoff but developed with VTE: 10.2% and 5.9%, respectively.

CONCLUSIONS

Integrating TD parameters into the Caprini score increases the ability to predict postoperative VTE.