A woman in her thirties with dyspnoea two weeks after abdominoplasty. / En kvinne i 30-årene med dyspné to uker etter bukplastikkoperasjon.

Background: While most cases of venous thromboembolism follow a benign course, occasionally the condition may manifest a complex clinical presentation and need a comprehensive diagnostic workup to identify the underlying cause and provide the patient with appropriate treatment. Case presentation: A woman in her late thirties presented to the emergency department with a five-day history of dyspnoea. She had recently undergone liposuction surgery after pregnancy. Upon admission, initial investigations revealed a pulmonary embolism with right heart strain, and she was treated with anticoagulants. The following day, she complained of acute-onset right flank pain without fever or other accompanying symptoms. A CT scan of the abdomen confirmed a right-side renal infarction. Further investigations revealed patent foramen ovale between the right and left atria of the heart, believed to be the source of a right-to-left shunt of arterial emboli. Although the patient had not suffered a clinical stroke, it was decided to close this defect using percutaneous technique. Interpretation: Patent foramen ovale is a common condition in adults, but in most cases it remains asymptomatic. However, patients with patent foramen ovale have an elevated risk of arterial emboli affecting multiple organs. The diagnosis depends on thorough assessment to prevent potentially fatal outcomes.

Epidemiological, clinical, therapeutic and evolutionary specificities of the association between venous thromboembolic event and cancer in sub-Saharan Africa: Case of Togo.

BACKGROUND: Our study aimed to describe the clinical, paraclinical, therapeutic and outcomes of patients with venous thromboembolic event (VTE) associated with cancer in the context of limited resources. MATERIALS AND METHODS: This was a descriptive cross-sectional study over a period of six years from March 1, 2016 to March 31, 2022, in the cardiology department and the oncology unit of the Sylvanus Olympio Teaching Hospital of Lome. Our study examined medical records of patients who were at least 18 years old and had venous thromboembolic disease and cancer that was histologically confirmed. This study did not include records that were incomplete or records from patients with coronavirus disease. RESULTS: Our study included 87 patients with average age of 56.36±15.26 years. The discovery of VTE occurred incidentally in 28.74%. Venous thrombosis was isolated in 68.96% and proximal in 95%. Pulmonary embolism was bilateral in 77.77%. Gynaecological and urological cancers were found in 33.33% and 32.19% respectively. Adenocarcinoma was the histological type of cancer found in 47.13%. Cancers were at a very advanced stage in 74.71%. Treatment with antivitamin K was prescribed in 12.65%. In our study, there were 58 patients who passed away with a mortality rate of 66.66%. The cause of death was a complication of VTE in 22.42% and related to the course of cancer in 63.79% of cases. CONCLUSION: VTE during cancer is particular with a fatal evolution due to the severity of VTE and the very advanced stage of cancer.

[Is low-dose anticoagulation a therapeutic option for patients at high risk of bleeding with high-risk pulmonary thromboembolism].

This issue of Chinese Journal of Tuberculosis and Respiratory Diseases published an interesting case illustrating the identification, treatment, and post-treatment management of a high-risk pulmonary thromboembolism (PTE) that occurred during surgery. It was a high-risk case of PTE, but during treatment, the risk stratification changed to medium-high risk. We should dynamically assess risk stratification and develop diagnosis and treatment plans based on changes in the patient's condition. At the same time, there was a high risk of bleeding in this patient. We should try to decrease the risk of bleeding as much as possible, consider all the conditions that can be applied at that time and on a local level, and devise a safe and effective treatment plan. The socio-economic status of patients may have an impact on how the final diagnosis and treatment plan are implemented. We need to communicate fully with patients, consider comprehensively, and prepare contingency plans to ensure patients' life safety to the greatest extent possible.

Delayed Diagnosis of Pulmonary Artery Thrombosis in a Patient Undergoing Mitral Valve Replacement.

ABSTRACT: The occurrence of pulmonary artery thrombus in association with rheumatic mitral stenosis is a rare complication. Pulmonary artery thrombus formation may worsen pulmonary artery pressures, and this may precipitate acute right heart failure. The possible mechanisms behind pulmonary artery thrombus formation during mitral valve replacement surgery could be acute coagulopathy following surgery, the presence of chronic pulmonary thromboembolism, or chronic atrial fibrillation. We report an unusual case of pulmonary artery thrombus in a patient with rheumatic MS which was diagnosed with transoesophageal echocardiography after MVR.

Predicting Pulmonary Embolism in Total Joint Arthroplasty Patients A Pilot Study.

Postoperative venous thromboembolism (VTE) is a common and costly complication following total joint arthroplasty (TJA). Development of a refined thrombophilic screening panel will better equip clinicians to identify patients at high-est risk for developing VTEs. In this pilot study, 62 high-risk TJA recipients who had developed pulmonary emboli (PE) within 90-days of surgery were eligible to participate. Of these patients, 14 were enrolled and subsequently adminis-tered a pre-determined panel of 18 hematologic tests with the aim of identifying markers that are consistently elevated or deficient in patients developing PE. A separate cohort of seven high-risk TJA recipients who did not report a symp-tomatic VTE within 90-days of surgery were then enrolled and Factor VIII and lipoprotein(a) levels were assessed. The most common aberrance was noted in 10 patients (71.4%) who had elevated levels of Factor VIII followed by five patients (35.7%) who had elevated levels of lipoprotein(a). Factor VIII was significantly prevalent (p < 0.001) while lipoprotein(a) failed to achieve statistical significance (p = 0.0708). Of the patients who were within normal limits of Factor VIII, three-fourths were "high-normal" with Fac-tor VIII levels within 5% of the upper limit of normal. This study demonstrates the potential utility of this hematologic panel as part of a perioperative screening protocol aimed at identifying patients at risk for developing VTEs. However, future larger scale studies assessing the capabilities and limitations of our findings are warranted.

Venous Thromboembolism in Foot and Ankle Trauma.

Every surgeon may have experienced a tragic event associated with death or debilitation secondary to deep vein thrombosis (DVT) or pulmonary embolism (PE) after foot and ankle trauma and surgery. Nevertheless, the prevention of such a tragic event needs to be carefully evaluated rationally with currently available epidemiologic data. With great postoperative protocols and access to care, most PE events can be prevented. There are modifiable risk factors, such as length/type of immobilization and operative trauma/time that can lower the incidence of DVT/PE. In addition, chemical prophylaxis may be warranted in certain people within the foot and ankle trauma population.

Spontaneous retroperitoneal haemorrhage after pulmonary endarterectomy surgery.

Spontaneous retroperitoneal hematoma (SRH) is a rare complication of anticoagulation therapy. Presentation may vary from limb paresis to hypovolemic shock due to blood loss. The optimal treatment is controversial. It can be managed conservatively or surgically. We report a case of a 73-year-old man presenting with progressively worsening abdominal pain and severe pain radiating to his left lower limb twenty-five days after his pulmonary endarterectomy (PEA) surgery. He was on anticoagulation per our institutional protocol for PEA patients. Investigations revealed a large, spontaneously occurring iliopsoas hematoma. Our patient was treated conservatively, and the SRH stabilised.

Mechanisms of Pulmonary Vasculopathy in Acute and Long-Term COVID-19: A Review.

Despite the end of the pandemic, coronavirus disease 2019 (COVID-19) remains a major public health concern. The first waves of the virus led to a better understanding of its pathogenesis, highlighting the fact that there is a specific pulmonary vascular disorder. Indeed, COVID-19 may predispose patients to thrombotic disease in both venous and arterial circulation, and many cases of severe acute pulmonary embolism have been reported. The demonstrated presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) within the endothelial cells suggests that direct viral effects, in addition to indirect effects of perivascular inflammation and coagulopathy, may contribute to pulmonary vasculopathy in COVID-19. In this review, we discuss the pathological mechanisms leading to pulmonary vascular damage during acute infection, which appear to be mainly related to thromboembolic events, an impaired coagulation cascade, micro- and macrovascular thrombosis, endotheliitis and hypoxic pulmonary vasoconstriction. As many patients develop post-COVID symptoms, including dyspnea, we also discuss the hypothesis of pulmonary vascular damage and pulmonary hypertension as a sequela of the infection, which may be involved in the pathophysiology of long COVID.

Nexplanonectomy-the surgical removal of an embolized implanted contraceptive device: a case report and review of the literature.

BACKGROUND: Nexplanon implants are a common hormonal contraceptive modality. Though rare, these devices can embolize into the injured wall of the basilic vein, through the right heart, and finally wedge itself into a pulmonary artery. With adherence to the arterial wall over time, it becomes less amenable to endovascular retrieval. Patients may present with symptoms mimicking a pulmonary embolism, or without any symptoms at all. In asymptomatic cases, endovascular retrieval and/or surgery is required when patients wish to begin having children prior to biological inactivity. The current literature showed as little as nine case reports detailing lung tissue removal in the aim of reversing a patient's implanted contraceptive device. CASE PRESENTATION: A 22-year-old asymptomatic active-duty Caucasian female presented for elective outpatient Nexplanon removal. The suspicion of possible implant migration arose when it was discovered to be non-palpable in her left arm. After plain film x-rays failed to localize the implant, a chest x-ray and follow-up Computed Tomography (CT) scan revealed that the Nexplanon had migrated to a distal branch of the left pulmonary artery. Due to the patient's strong desires to begin having children, the decision was made for removal. Initial endovascular retrieval failed due to Nexplanon encapsulation within the arterial wall. Ultimately, the patient underwent a left video-assisted thoracoscopic surgery (VATS) for exploration and left lower lobe basilar S7-9 segmentectomy, which successfully removed the Nexplanon. CONCLUSIONS: Implanted contraceptive devices can rarely result in migration to the pulmonary vasculature. These radiopaque devices are detectable on imaging studies if patients and clinicians are unable to palpate them. An endovascular approach should be considered first to spare lung tissue and avoid chest-wall incisions, but can be complicated by encapsulation and adherence to adjacent tissue. A VATS procedure with single-lung ventilation via a double-lumen endotracheal tube allows surgeons to safely operate on an immobilized lung while anesthesiologists facilitate single-lung ventilation. This patient's case details the uncommon phenomenon of Nexplanon migration, and the exceedingly rare treatment resolution of lung resection to remove an embolized device.

An Unusual Case of Treatment-naive HIV Patient Presenting with Acute Pancreatitis in Sepsis with Infective Endocarditis and Bilateral Pulmonary Thromboembolism.

Acute pancreatitis is seen in patients with human immunodeficiency virus (HIV) as a result of antiretroviral drug therapy and hypertriglyceridemia. Thrombotic complications are known in patients of HIV as a result of endothelial dysfunction, and right-sided infective endocarditis (IE) is seen in HIV patients mostly due to intravenous (IV) drug abuse. However, the occurrence of acute pancreatitis with sepsis, IE, and bilateral thromboembolism in the same patient is rare. Here, we report this case of a treatment-naive nondrug abuser HIV patient with acute pancreatitis in sepsis, IE, and bilateral pulmonary thromboembolism who recovered completely with treatment.

A systematic review of thromboembolic complications and outcomes in hospitalised COVID-19 patients.

Thromboembolic (TE) complications [myocardial infarction (MI), stroke, deep vein thrombosis (DVT), and pulmonary embolism (PE)] are common causes of mortality in hospitalised COVID-19 patients. Therefore, this review was undertaken to explore the incidence of TE complications and mortality associated with TE complications in hospitalised COVID-19 patients from different studies. A literature search was performed using ScienceDirect and PubMed databases using the MeSH term search strategy of "COVID-19", "thromboembolic complication", "venous thromboembolism", "arterial thromboembolism", "deep vein thrombosis", "pulmonary embolism", "myocardial infarction", "stroke", and "mortality". There were 33 studies included in this review. Studies have revealed that COVID-19 patients tend to develop venous thromboembolism (PE:1.0-40.0% and DVT:0.4-84%) compared to arterial thromboembolism (stroke:0.5-15.2% and MI:0.8-8.7%). Lastly, the all-cause mortality of COVID-19 patients ranged from 4.8 to 63%, whereas the incidence of mortality associated with TE complications was between 5% and 48%. A wide range of incidences of TE complications and mortality associated with TE complications can be seen among hospitalized COVID-19 patients. Therefore, every patient should be assessed for the risk of thromboembolic complications and provided with an appropriate thromboprophylaxis management plan tailored to their individual needs.

Fatal pulmonary bile embolism associated with acute pancreatitis - a case report and review of the literature.

A 27-year-old woman with jaundice and abdominal pain was admitted to an emergency ward. The diagnostic process showed that gallstones were causing her symptoms. The patient was treated via endoscopic retrograde cholangiopancreatography (ERCP), and during the procedure she suffered a cardiac arrest. Autopsy findings included multiple pulmonary bile emboli as well as features of disseminated intravascular coagulation. Among 22 thus far described cases of bile pulmonary embolism, 13 were associated with medical procedures involving the liver and biliary tract. We present the case report of a pulmonary bile embolism associated with acute pancreatitis treated via ERCP in a woman with gallbladder bile stones.

Exploring Risk Factors for Lower Extremity Deep Vein Thrombosis Patients with Co-existing Pulmonary Embolism Based on Multiple Logistic Regression Model.

Valuable data on deep vein thrombosis (DVT) patients with coexisting pulmonary embolism (PE) is scarce. This study aimed to identify risk factors associated with these patients and develop logistic regression models to select high-risk DVT patients with coexisting PE. We retrospectively collected data on 150 DVT patients between July 15, 2022, and June 15, 2023, dividing them into groups based on the presence of coexisting PE. Univariate and multivariate logistic regression analyses were performed to identify significant risk factors and construct predictive models. Discrimination and calibration statistics evaluated the validation and accuracy of the developed models. Of the 130 patients analyzed, 40 (30.77%) had coexisting PE. Univariate analysis revealed four significant predictors of DVT patients with coexisting PE: sex (OR 3.83, 95% CI: [1.76; 8.59], P = 0.001), body mass index (BMI) (OR 1.50, 95% CI: [1.28; 1.75], P < 0.001), chronic disease (OR 5.15, 95% CI: [2.32; 11.8], P < 0.001), and high-density lipoprotein (HDL) (OR 0.03, 95% CI: [0.01; 0.20], P < 0.001). Additionally, BMI > 24 kg/m2 (OR 9.70, 95% CI: [2.70; 67.5], P < 0.001) and BMI > 28 kg/m2 (OR 4.80, 95% CI: [2.15; 11.0], P < 0.001) were associated with concurrent PE. Three multiple regression models were constructed, with areas under the receiver-operating characteristic curves of 0.925 (95% CI: [0.882; 0.968]), 0.908 (95% CI: [0.859; 0.957]), and 0.890 (95% CI: [0.836; 0.944]), respectively. Sex, BMI, chronic disease, and HDL levels are significant predictors of DVT patients with coexisting PE.

Pulmonary Thromboembolism following Russell's Viper Bites.

Snakebite envenoming and its resulting complications are serious threats to the health of vulnerable people living in rural areas of developing countries. The knowledge of the heterogeneity of symptoms associated with snakebite envenoming and their management strategies is vital to treat such life-threatening complications to save lives. Russell's viper envenomation induces a diverse range of clinical manifestations from commonly recognised haemotoxic and local effects to several rare conditions that are often not reported. The lack of awareness about these unusual manifestations can affect prompt diagnosis, appropriate therapeutic approaches, and positive outcomes for patients. Here, we report pulmonary thromboembolism that developed in three patients following Russell's viper envenomation and demonstrate their common clinical features and diagnostic and therapeutic approaches used. All patients showed clinical signs of local (oedema) and systemic (blood coagulation disturbances) envenomation, which were treated using polyvalent antivenom. They exhibited elevated heart rates, breathlessness, and reduced oxygen saturation, which are non-specific but core parameters in the diagnosis of pulmonary embolism. The recognition of pulmonary embolism was also achieved by an electrocardiogram, which showed sinus tachycardia and computed tomography and echocardiogram scans further confirmed this condition. Anti-coagulant treatment using low-molecular-weight heparin offered clinical benefits in these patients. In summary, this report reinforces the broad spectrum of previously unreported consequences of Russell's viper envenomation. The constant updating of healthcare professionals and the dissemination of major lessons learned in the clinical management of snakebite envenoming through scientific documentation and educational programs are necessary to mitigate the adverse impacts of venomous snakebites in vulnerable communities.

Septic arthritis of the native hip joint and septic pulmonary embolism in an adult with sickle cell trait after a complicated dental extraction.

Septic arthritis (SA) is a serious infection of the joint which can lead to irreversible destruction of the joint.We report a case of right hip SA with septic pulmonary embolism following a complicated dental extraction in a woman in her early 40s with sickle cell trait (SCT).The patient presented with severe right thigh pain and left jaw pain.Initial workup revealed raised C reactive protein and positive blood cultures. Right hip joint SA was confirmed following intraoperative joint aspiration. The patient had right hip debridement with long-term intravenous antibiotics.The incidence of SA in adults with sickle cell disease is low: 0.3% in a study in France and Brazil and 10.3% incidence of haematogenous osteoarticular infection in children with SCT in West Africa.

Venous Thromboembolism Risk Factors in Women With Obesity Who Undergo Cesarean Delivery.

Venous thromboembolism (VTE) is a leading cause of maternal mortality. Obesity and cesarean delivery are established risk factors for pregnancy-related VTE. We identified additional risk factors among patients with obesity who underwent a cesarean delivery to identify those who need VTE prophylaxis. We conducted a secondary analysis of data from the Maternal-Fetal Medicine Units Network (MFMU) Cesarean Registry Database using a case-control design. Cases were identified as women with obesity having a pre-pregnancy body mass index of >30 kg/m2, who underwent cesarean delivery and subsequently developed deep venous thrombosis (DVT) or pulmonary embolism (PE). These women were compared to a control group of women with obesity who underwent cesarean delivery but did not develop DVT or PE. Analysis of risk factors associated with VTE was performed using Chi-Square test and Fisher's exact test. We identified 43 VTE cases and 172 controls in the MFMU database. Increased risk of VTE was noted in women with endometritis (OR of 4.58 [95% CI: 1.86-11.2, P = .0004]), receiving a blood transfusion (OR 17.07 [95% CI: 4.46-65.3, P = .0001]), having a coagulopathy (OR 27.73 [95% CI: 3.24-237.25, P = .0003]), and urinary tract infection (OR 2.39 [95% CI: 1.08-5.28, P = .03]). Important risk factors for VTE in women with obesity who undergo cesarean delivery include endometritis, intra- or post-operative transfusion, coagulopathy, and urinary tract infection. The presence of one or more of these factors may help guide provider decision-making regarding whether to administer thromboprophylaxis.

Predictive factors of clot propagation in patients with superficial venous thrombosis towards deep venous thrombosis and pulmonary embolism: a systematic review and meta-analysis.

OBJECTIVE: A subset of patients with superficial venous thrombosis (SVT) experiences clot propagation towards deep venous thrombosis (DVT) and/or pulmonary embolism (PE). The aim of this systematic review is to identify all clinically relevant cross-sectional and prognostic factors for predicting thrombotic complications in patients with SVT. DESIGN: Systematic review. DATA SOURCES: PubMed/MEDLINE and Embase were systematically searched until 3 March 2023. ELIGIBILITY CRITERIA: Original research studies with patients with SVT, DVT and/or PE as the outcome and presenting cross-sectional or prognostic predictive factors. DATA EXTRACTION AND SYNTHESIS OF RESULTS: The CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling (CHARMS) checklist for prognostic factor studies was used for systematic extraction of study characteristics. Per identified predictive factor, relevant estimates of univariable and multivariable predictor-outcome associations were extracted, such as ORs and HRs. Estimates of association for the most frequently reported predictors were summarised in forest plots, and meta-analyses with heterogeneity were presented. The Quality in Prognosis Studies (QUIPS) tool was used for risk of bias assessment and Grading of Recommendations, Assessment, Development and Evaluations (GRADE) for assessing the certainty of evidence. RESULTS: Twenty-two studies were included (n=10 111 patients). The most reported predictive factors were high age, male sex, history of venous thromboembolism (VTE), absence of varicose veins and cancer. Pooled effect estimates were heterogenous and ranged from OR 3.12 (95% CI 1.75 to 5.59) for the cross-sectional predictor cancer to OR 0.92 (95% CI 0.56 to 1.53) for the prognostic predictor high age. The level of evidence was rated very low to low. Most studies were scored high or moderate risk of bias. CONCLUSIONS: Although the pooled estimates of the predictors high age, male sex, history of VTE, cancer and absence of varicose veins showed predictive potential in isolation, variability in study designs, lack of multivariable adjustment and high risk of bias prevent firm conclusions. High-quality, multivariable studies are necessary to be able to identify individual SVT risk profiles. PROSPERO REGISTRATION NUMBER: CRD42021262819.

Successful Treatment Strategy for Duplicate Inferior Vena Cava and Deep Venous Thrombosis: Filter Placement and Thrombolysis Approach.

BACKGROUND Duplicate inferior vena cava (IVC) accompanied by deep venous thrombosis is rare. The optimal treatment plan is determined according to the results of imaging, including venography. In this report, we present a case of successful treatment of a patient with duplicate IVC and deep venous thrombosis (DVT). CASE REPORT An 84-year-old man with history of hypertension was admitted to the hospital because of 4 days of moderate left lower-limb edema. A thorough examination led to the diagnosis of the DVT. The duplicate IVC was discovered during venography. As the blood from the left common iliac vein mainly flowed to the left IVC, and there were no other communicating branches before the convergence of the left and right IVCs, which was located above the 1st lumbar vertebrae body near the junction of the hepatic vein and the IVC, the strategy of placing only 1 filter in the left inferior vena cava were chosen, rather than placing 1 filter above the confluence of bilateral IVC, or placing a filter in each IVC below the level of renal veins on each side. Following that, the DVT was safely treated with thrombolysis and aspiration without the risk of pulmonary embolism. CONCLUSIONS This case report presented the complete evaluation and management of a patient with lower-limb DVT accompanied by the malformation of duplicate IVC. The filter placement strategy with duplicate IVC in the literature was summarized. We concluded that even in emergency situations, with comprehensive consideration, it is possible to perform endovascular intervention successfully and achieve satisfactory treatment results.

Prevalence of Pulmonary Embolism in COVID-19 at Quaternary Hospital Running Head: Pulmonary Embolism in COVID-19.

Background: Patients with COVID-19 are at greater risk of pulmonary embolism. Objective: The aim of the present study was to evaluate the monthly prevalence of pulmonary embolism diagnosed by angiotomography and mortality between March 2020 and May 2021 in more than 6000 patients hospitalized with COVID-19 at a single institution. Methods: A clinical trial was conducted with evaluated medical records the patients hospitalized at the institution who developed pulmonary embolism determined by angiotomography. Monthly and overall mortality rates between March 2020 and May 2021 in this population were evaluated. Results: A total of 6040 patients were hospitalized in this period, 203 of whom (3.36%) had an angiotomographic diagnosis of pulmonary embolism and 119 of these patients (58.62%) died. The largest number of patients with pulmonary embolism occurred in the periods from July to September 2020 and March to May 2021. No significant difference was found between mortality and the two peaks of the pandemic (p = 0.9, Fisher's exact test). Conclusion: Pulmonary embolism is associated a higher mortality rate among patients with COVID-19. Therefore, one of the strategies is an emphasis on the prevention of thrombotic and embolic events.

Aspirin versus low-molecular-weight heparin for thromboprophylaxis after orthopaedic surgery: a systematic review and meta-analysis.

The article aimed to compare the efficiency and safety of aspirin with low-molecular-weight heparin (LMWH) for thromboprophylaxis in orthopaedic surgery patients. According to the inclusion and exclusion criteria, PubMed, Embase and Cochrane Library database were searched for studies comparing aspirin and LMWH in venous thromboembolism (VTE) prophylaxis until 25 April 2023. The outcome measures included deep venous thrombosis(DVT)/Pulmonary embolism(PE) events, major bleeding events, wound complications, wound infection and death. Six studies met the requirements of our meta-analysis, including 12 470 patients in the aspirin group and 10 857 patients in the LMWH group. The meta-analysis showed that results showed that LMWH was superior to aspirin in preventing VTE events (odds ratio (OR) 1.44, 95% CI 1.24-1.68, P  < 0.00001), whereas there was no significant difference between them in bleeding events (OR 0.95, 95% CI 0.86-1.05, P  = 0.33), wound complication (OR 0.58, 95% CI 0.28-1.17, P  = 0.13), wound infection (OR 1.12, 95% CI 0.86-1.47, P  = 0.39) and mortality (OR 1.04, 95% CI 0.70-1.55, P  = 0.83). In addition, subgroup analysis showed that compared with aspirin, LMWH was more likely to reduce the incidence of DVT events in orthopaedic surgery patients (OR 1.59, 95% CI 1.33-1.91, P  < 0.00001), whereas there was no advantage in reducing the incidence of PE events (OR 1.22, 95% CI 0.62-2.40, P  = 0.56). Despite the similar safety profiles, this meta-analysis showed that LMWH was significantly superior to aspirin in thromboprophylaxis after orthopaedic surgery. LMWH was still the first-line drug for thrombosis prevention in patients who underwent major orthopaedic surgeries.