Fondaparinux versus nadroparin for thromboprophylaxis following minimally invasive esophagectomy: A randomized controlled trial

Comparison of efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism in lower extremities after total hip arthroplasty and total knee arthroplasty: a retrospective study of 592 patients

OBJECTIVES

To compare the efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism (DVT) in lower extremities after total hip arthroplasty (THA) and total knee arthroplasty (TKA).

METHODS

A total of 592 patients were enrolled in the study. Clinical data of patients who underwent total hip arthroplasty (THA) and total knee arthroplasty (TKA) in our hospital from December 2021 to September 2022 were retrospectively collected, which mainly included patients' general information, surgery-related information, and DVT-related information. The patients were categorized into the nadroparin group(n = 278) and the fondaparinux sodium group(n = 314) according to the types of anticoagulants used. Anticoagulant therapy began 12-24 h after operation and continued until discharge. DVT prevalence between two groups was compared. The Statistical Package for Social Sciences (SPSS) software version 25 (SPSS, Armonk, NY, USA) was used for statistical analysis.

RESULTS

The prevalence of DVT in the nadroparin group and the fondaparinux sodium group was 8.3% (23/278) and 15.0% (47/314), respectively(p = 0.012). Statistical analysis showed that nadroparin group showed a lower prevalence of thrombosis than fondaparinux group (OR = 1.952, P = 0.012). Subgroup analyses showed that nadroparin group had a lower prevalence of DVT than fondaparinux group in some special patients groups such as female patients (OR = 2.258, P = 0.007), patients who are 65-79 years old (OR = 2.796, P = 0.004), patients with hypertension (OR = 2.237, P = 0.042), patients who underwent TKA (OR = 2.091, P = 0.011), and patients who underwent combined spinal-epidural anesthesia (OR = 2.490, P = 0.003) (P < 0.05).

CONCLUSION

Nadroparin may have an advantage over fondaparinux sodium in preventing DVT in lower extremities after THA and TKA.

Rivaroxaban versus nadroparin for thromboprophylaxis following thoracic surgery for lung cancer: A randomized, noninferiority trial

The benefit of rivaroxaban in thromboprophylaxis after oncologic lung surgery remains unknown. To evaluate the efficacy and safety of rivaroxaban, patients who underwent thoracic surgery for lung cancer were enrolled, and randomly assigned to rivaroxaban or nadroparin groups in a 1:1 ratio; anticoagulants were initiated 12-24 h after surgery and continued until discharge. Four hundred participants were required according to a noninferiority margin of 2%, assuming venous thromboembolism (VTE) occurrence rates of 6.0% and 12.6% for patients in the rivaroxaban and nadroparin groups, respectively. The primary efficacy outcome was any VTE during the treatment and 30-day follow-up periods. The safety outcome was any on-treatment bleeding event. Finally, 403 patients were randomized (intention-to-treat [ITT] population), with 381 included in per-protocol (PP) population. The primary efficacy outcomes occurred in 12.5% (25/200) of the rivaroxaban group and 17.7% (36/203) of the nadroparin group (absolute risk reduction, -5.2%; 95% confidence interval [CI], [-12.2-1.7]), indicating the noninferiority of rivaroxaban in ITT population. Sensitivity analysis was performed in the PP population and yielded similar results, confirming the noninferiority of rivaroxaban. In the safety analysis population, the incidence of any on-treatment bleeding events did not differ significantly between the groups (12.2% for rivaroxaban vs. 7.0% for nadroparin; relative risk [RR], 1.9; 95% CI, [0.9-3.7]; p = .08), including major bleeding (9.7% vs. 6.5%; RR, 1.6 [95% CI, 0.9-3.7]; p = .24), and nonmajor bleeding (2.6% vs. 0.5%; RR, 5.2 [95% CI, 0.6-45.2]; p = .13). Rivaroxaban for thromboprophylaxis after oncologic lung surgery was shown to be noninferior to nadroparin.

The fragility of significant results from randomized controlled trials in esophageal surgeries

While randomized controlled trials (RCTs) are regarded as one of the highest forms of clinical research, the robustness of their P values can be difficult to ascertain. Defined as the minimum number of patients in a study arm that would need to be changed from a non-event to event for the findings to lose significance, the Fragility Index is a method for evaluating results from these trials. This study aims to calculate the Fragility Index for trials evaluating perioperative esophagectomy-related interventions to determine the strength of RCTs in this field. MEDLINE and EMBASE were searched for RCTs related to esophagectomy that reported a significant dichotomous outcome. Two reviewers independently screened articles and performed the data extractions with risk of bias assessment. The Fragility Index was calculated using a two-tailed Fisher's exact test. Bivariate correlation was conducted to evaluate associations between the Fragility Index and study characteristics. 41 RCTs were included, and the median sample size was 80 patients [Interquartile range (IQR) 60-161]. Of the included outcomes, 29 (71%) were primary, and 12 (29%) were secondary. The median Fragility Index was 1 (IQR 1-3), meaning that by changing one patient from a non-event to event, the results would become non-significant. Fragility Index was correlated with P value, number of events, and journal impact factor. The RCTs related to esophagectomy did not prove to be robust, as the significance of their results could be changed by altering the outcome status of a handful of patients in one study arm.

Venous Thromboembolism Following Major Abdominal Surgery for Cancer: A Guide for the Surgical Intern

BACKGROUND

Venous thromboembolism (VTE) is a term used to compositely describe deep vein thrombosis (DVT) and pulmonary embolism (PE). Overall, the incidence of VTE after major abdominal and pelvic surgery has been reported to be between 10% and 40%.

OBJECTIVE

To estimate the incidence of post-operative VTE in patients undergoing major abdominal surgery for cancer, to identify risk factors associated with VTE, and to assess available thromboprophylaxis tools.

METHODS

A Medline and Cochrane literature search from database inception until February 1st, 2021 was performed according to the PRISMA (Preferred Reporting Items for Systematic reviews and Meta-Analyses) guidelines.

RESULTS

Thirty-one studies met our eligibility criteria and were included in the current review. In total, 435,492 patients were identified and the overall incidence of VTE was 2.19%( 95% CI: 1.82-2.38). Τhe following risk factors were associated with VTE: smoking, advanced age (>70 years), a history of diabetes mellitus, American Society of Anesthesiologists' (ASA) classification of Physical Health class III or IV, a history of cardiovascular or pulmonary disease, a history of DVT or PE, elevated plasma fibrinogen level, c-reactive protein (CRP) level, cancer stage III or IV, postoperative acute respiratory distress syndrome (ARDS), prolonged postoperative hospital stay, previous steroid use, history of Inflammatory Bowel Disease (IBD), heart failure and neoadjuvant and adjuvant chemotherapy.

CONCLUSION

VTE remains an important complication after major abdominal surgery for cancer and seems to increase mortality rates.

Oral anticoagulation in people with cancer who have no therapeutic or prophylactic indication for anticoagulation

BACKGROUND

Oral anticoagulants may improve the survival of people with cancer through an antithrombotic effect, yet increase the risk of bleeding.

OBJECTIVES

To evaluate the efficacy and safety of oral anticoagulants in ambulatory people with cancer undergoing chemotherapy, targeted therapy, immunotherapy, or radiotherapy (either alone or in combination), with no standard therapeutic or prophylactic indication for anticoagulation.

SEARCH METHODS

We conducted comprehensive searches on 14 June 2021, following the original electronic searches performed in February 2016 (last major search). We electronically searched the following databases: CENTRAL, MEDLINE, Embase. In addition, we handsearched conference proceedings, checked references of included studies, and searched for ongoing studies. As part of the living systematic review approach, we are running continual searches and will incorporate new evidence rapidly after it is identified.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) assessing the benefits and harms of vitamin K antagonists (VKAs) or direct oral anticoagulants (DOACs) in ambulatory people with cancer (i.e., not hospital inpatients during the time of their participation in trials) These people are typically undergoing systemic anticancer therapy, possibly including chemotherapy, targeted therapy, immunotherapy, or radiotherapy, but otherwise have no standard therapeutic or prophylactic indication for anticoagulation.

DATA COLLECTION AND ANALYSIS

Using a standardised form, two review authors independently extracted data on study design, participants, intervention outcomes of interest, and risk of bias. Outcomes of interest included all-cause mortality, pulmonary embolism, symptomatic deep vein thrombosis (DVT), major bleeding, minor bleeding and health-related quality of life. We assessed the certainty of evidence for each outcome using the GRADE approach.

MAIN RESULTS

Of 12,620 identified citations, 10 RCTs fulfilled the inclusion criteria. The oral anticoagulant was a vitamin K antagonist (VKA) in six of these RCTs, and a direct oral anticoagulant (DOAC) in the remaining four RCTs (three studies used apixaban; one used rivaroxaban). The comparator was either placebo or no prophylaxis. Compared to no prophylaxis, vitamin K antagonists (VKAs) probably reduce mortality at six months slightly (risk ratio (RR) 0.93, 95% confidence interval (CI) 0.77 to 1.13; risk difference (RD) 22 fewer per 1000, 95% CI 72 fewer to 41 more; moderate-certainty evidence), and probably reduce mortality at 12 months slightly (RR 0.95, 95% CI 0.87 to 1.03; RD 29 fewer per 1000, 95% CI 75 fewer to 17 more; moderate-certainty evidence). One study assessed the effect of a VKA compared to no prophylaxis on thrombosis; the evidence was very uncertain about the effect of VKA compared to no VKA on pulmonary embolism and symptomatic DVT (RR 1.05, 95% CI 0.07 to 16.58; RD 0 fewer per 1000, 95% CI 6 fewer to 98 more; very low-certainty evidence; RR 0.08, 95% CI 0.01 to 1.42; RD 35 fewer per 1000, 95% CI 37 fewer to 16 more; very low-certainty evidence, respectively). Also, VKAs probably increase major and minor bleeding at 12 months (RR 2.93, 95% CI 1.86 to 4.62; RD 107 more per 1000, 95% CI 48 more to 201 more; moderate-certainty evidence for major bleeding, and RR 3.14, 95% CI 1.85 to 5.32; RD 167 more per 1000, 95% CI 66 more to 337 more; moderate-certainty evidence for minor bleeding). Compared to no prophylaxis, at three to six months, direct oral anticoagulants (DOACs) probably reduce mortality slightly (RR 0.94, 95% CI 0.64 to 1.38, RD 11 fewer per 1000, 95% CI 67 fewer to 70 more; moderate-certainty evidence), probably reduce the risk of pulmonary embolism slightly compared to no prophylaxis (RR 0.48, 95% CI 0.24 to 0.98; RD 24 fewer per 1000, 95% CI 35 fewer to 1 fewer; moderate-certainty evidence), probably reduce symptomatic DVT slightly (RR 0.58, 95% CI 0.30 to 1.15; RD 21 fewer per 1000, 95% CI 35 fewer to 8 more; moderate-certainty evidence), probably do not increase major bleeding (RR 1.65, 95% CI 0.72 to 3.80; RD 9 more per 1000, 95% CI 4 fewer to 40 more; moderate-certainty evidence), and may increase minor bleeding (RR 3.58, 95% CI 0.55 to 23.44; RD 55 more per 1000, 95% CI 10 fewer to 482 more; low-certainty evidence).

AUTHORS' CONCLUSIONS

In ambulatory people with cancer undergoing chemotherapy, targeted therapy, immunotherapy, or radiotherapy (either alone or in combination), the current evidence on VKA thromboprophylaxis suggests that the harm of major bleeding might outweigh the benefit of reduction in venous thromboembolism. With DOACs, the benefit of reduction in venous thromboembolic events outweighs the risk of major bleeding. Editorial note: this is a living systematic review. Living systematic reviews offer a new approach to review updating in which the review is continually updated, incorporating relevant new evidence, as it becomes available. Please refer to the 'What's new' section in the  Cochrane Database of Systematic Reviews for the current status of this review.

Venous thromboembolism after esophagectomy for cancer: a systematic review of the literature to evaluate incidence, risk factors, and prophylaxis

PURPOSE

Although esophagectomy remains the preferred treatment for esophageal cancer, it is still associated with a number of complications, including post-operative venous thromboembolism (VTE). The aim of this study was to summarize the reported incidence of VTE after esophagectomy, its risk factors, and prevention strategies.

METHODS

We conducted a systematic search of the literature in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

RESULTS

Fourteen studies met our inclusion criteria and were selected in the present review. Overall, we identified 9768 patients who underwent esophagectomy, with a post-operative VTE rate of 4% (440 patients). The reported risk factors for VTE included advanced age, American Society of Anesthesiologists (ASA) class III or IV, a history of cardiovascular or pulmonary disease, and the implementation of preoperative chemo-radiotherapy. Postoperative acute respiratory distress syndrome was also associated with VTE. No universally applied prevention strategies for VTE after esophagectomy were identified in the literature.

CONCLUSIONS

Despite advances in perioperative care, VTE after esophagectomy still represents a source of morbidity for about 4% of patients. Low molecular weight heparin is suggested as the routine standard prophylactic regimen after esophageal cancer surgery.

American Society of Hematology 2021 guidelines for management of venous thromboembolism: prevention and treatment in patients with cancer

BACKGROUND

Venous thromboembolism (VTE) is a common complication among patients with cancer. Patients with cancer and VTE are at a markedly increased risk for morbidity and mortality.

OBJECTIVE

These evidence-based guidelines of the American Society of Hematology (ASH) are intended to support patients, clinicians, and other health care professionals in their decisions about the prevention and treatment of VTE in patients with cancer.

METHODS

ASH formed a multidisciplinary guideline panel balanced to minimize potential bias from conflicts of interest. The guideline development process was supported by updated or new systematic evidence reviews. The Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach was used to assess evidence and make recommendations.

RESULTS

Recommendations address mechanical and pharmacological prophylaxis in hospitalized medical patients with cancer, those undergoing a surgical procedure, and ambulatory patients receiving cancer chemotherapy. The recommendations also address the use of anticoagulation for the initial, short-term, and long-term treatment of VTE in patients with cancer.

CONCLUSIONS

Strong recommendations include not using thromboprophylaxis in ambulatory patients receiving cancer chemotherapy at low risk of VTE and to use low-molecular-weight heparin (LMWH) for initial treatment of VTE in patients with cancer. Conditional recommendations include using thromboprophylaxis in hospitalized medical patients with cancer, LMWH or fondaparinux for surgical patients with cancer, LMWH or direct oral anticoagulants (DOAC) in ambulatory patients with cancer receiving systemic therapy at high risk of VTE and LMWH or DOAC for initial treatment of VTE, DOAC for the short-term treatment of VTE, and LMWH or DOAC for the long-term treatment of VTE in patients with cancer.

The venous thromboembolism prophylaxis in patients receiving thoracic surgery: A systematic review

OBJECTIVES

Venous thromboembolism (VTE) is a significant and preventable cause of mortality and morbidity in thoracic surgery. It usually deep venous thromboembolism (DVT) and pulmonary thromboembolism (PE). We conducted this article to perform a systematic review on prophylaxis of perioperative VTE in patients undergoing thoracic surgery especially lung surgery and esophageal surgery and to identify potential areas for future research.

METHODS

The systematic review we conducted included studies of patients undergoing thoracic surgery especially lung surgery and esophageal surgery RESULTS: The study identified 2621 references. Finally, 22 trials with a total of 9072 patients were included. Only six studies declared that they continued a follow-up after the discharge of the patients. (range: 1-3 months); three studies reported on major bleeding events as an outcome measure, and the incidence varied from 0.8% to 1.6%. Total 346 VTEs occurred, and the overall mean risk of VTE was estimated at 3.8% (range: 0.77-27%).

CONCLUSIONS

The evidence for using thromboprophylaxis in thoracic surgery is limited and controversial, predominantly based on clinical consensus. Future research is needed to focus on identifying risk of VTE and providing sufficient evidence with high quality to support clinical strategies concerning the prophylaxis for VTE.

Anticoagulation for perioperative thromboprophylaxis in people with cancer

BACKGROUND

The choice of the appropriate perioperative thromboprophylaxis for people with cancer depends on the relative benefits and harms of different anticoagulants.

OBJECTIVES

To systematically review the evidence for the relative efficacy and safety of anticoagulants for perioperative thromboprophylaxis in people with cancer.

SEARCH METHODS

This update of the systematic review was based on the findings of a comprehensive literature search conducted on 14 June 2018 that included a major electronic search of Cochrane Central Register of Controlled Trials (CENTRAL, 2018, Issue 6), MEDLINE (Ovid), and Embase (Ovid); handsearching of conference proceedings; checking of references of included studies; searching for ongoing studies; and using the 'related citation' feature in PubMed.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that enrolled people with cancer undergoing a surgical intervention and assessed the effects of low-molecular weight heparin (LMWH) to unfractionated heparin (UFH) or to fondaparinux on mortality, deep venous thrombosis (DVT), pulmonary embolism (PE), bleeding outcomes, and thrombocytopenia.

DATA COLLECTION AND ANALYSIS

Using a standardized form, we extracted data in duplicate on study design, participants, interventions outcomes of interest, and risk of bias. Outcomes of interest included all-cause mortality, PE, symptomatic venous thromboembolism (VTE), asymptomatic DVT, major bleeding, minor bleeding, postphlebitic syndrome, health related quality of life, and thrombocytopenia. We assessed the certainty of evidence for each outcome using the GRADE approach (GRADE Handbook).

MAIN RESULTS

Of 7670 identified unique citations, we included 20 RCTs with 9771 randomized people with cancer receiving preoperative prophylactic anticoagulation. We identified seven reports for seven new RCTs for this update.The meta-analyses did not conclusively rule out either a beneficial or harmful effect of LMWH compared with UFH for the following outcomes: mortality (risk ratio (RR) 0.82, 95% confidence interval (CI) 0.63 to 1.07; risk difference (RD) 9 fewer per 1000, 95% CI 19 fewer to 4 more; moderate-certainty evidence), PE (RR 0.49, 95% CI 0.17 to 1.47; RD 3 fewer per 1000, 95% CI 5 fewer to 3 more; moderate-certainty evidence), symptomatic DVT (RR 0.67, 95% CI 0.27 to 1.69; RD 3 fewer per 1000, 95% CI 7 fewer to 7 more; moderate-certainty evidence), asymptomatic DVT (RR 0.86, 95% CI 0.71 to 1.05; RD 11 fewer per 1000, 95% CI 23 fewer to 4 more; low-certainty evidence), major bleeding (RR 1.01, 95% CI 0.69 to 1.48; RD 0 fewer per 1000, 95% CI 10 fewer to 15 more; moderate-certainty evidence), minor bleeding (RR 1.01, 95% CI 0.76 to 1.33; RD 1 more per 1000, 95% CI 34 fewer to 47 more; moderate-certainty evidence), reoperation for bleeding (RR 0.93, 95% CI 0.57 to 1.50; RD 4 fewer per 1000, 95% CI 22 fewer to 26 more; moderate-certainty evidence), intraoperative transfusion (mean difference (MD) -35.36 mL, 95% CI -253.19 to 182.47; low-certainty evidence), postoperative transfusion (MD 190.03 mL, 95% CI -23.65 to 403.72; low-certainty evidence), and thrombocytopenia (RR 3.07, 95% CI 0.32 to 29.33; RD 6 more per 1000, 95% CI 2 fewer to 82 more; moderate-certainty evidence). LMWH was associated with lower incidence of wound hematoma (RR 0.70, 95% CI 0.54 to 0.92; RD 26 fewer per 1000, 95% CI 39 fewer to 7 fewer; moderate-certainty evidence). The meta-analyses found the following additional results: outcomes intraoperative blood loss (MD -6.75 mL, 95% CI -85.49 to 71.99; moderate-certainty evidence); and postoperative drain volume (MD 30.18 mL, 95% CI -36.26 to 96.62; moderate-certainty evidence).In addition, the meta-analyses did not conclusively rule out either a beneficial or harmful effect of LMWH compared with Fondaparinux for the following outcomes: any VTE (DVT or PE, or both; RR 2.51, 95% CI 0.89 to 7.03; RD 57 more per 1000, 95% CI 4 fewer to 228 more; low-certainty evidence), major bleeding (RR 0.74, 95% CI 0.45 to 1.23; RD 8 fewer per 1000, 95% CI 16 fewer to 7 more; low-certainty evidence), minor bleeding (RR 0.83, 95% CI 0.34 to 2.05; RD 8fewer per 1000, 95% CI 33 fewer to 52 more; low-certainty evidence), thrombocytopenia (RR 0.35, 95% CI 0.04 to 3.30; RD 14 fewer per 1000, 95% CI 20 fewer to 48 more; low-certainty evidence), any PE (RR 3.13, 95% CI 0.13 to 74.64; RD 2 more per 1000, 95% CI 1 fewer to 78 more; low-certainty evidence) and postoperative drain volume (MD -20.00 mL, 95% CI -114.34 to 74.34; low-certainty evidence) AUTHORS' CONCLUSIONS: We found no difference between perioperative thromboprophylaxis with LMWH versus UFH and LMWH compared with fondaparinux in their effects on mortality, thromboembolic outcomes, major bleeding, or minor bleeding in people with cancer. There was a lower incidence of wound hematoma with LMWH compared to UFH.