Synthesis of bioengineered heparin chemically and biologically similar to porcine-derived products and convertible to low MW heparin.

Heparins have been invaluable therapeutic anticoagulant polysaccharides for over a century, whether used as unfractionated heparin or as low molecular weight heparin (LMWH) derivatives. However, heparin production by extraction from animal tissues presents multiple challenges, including the risk of adulteration, contamination, prion and viral impurities, limited supply, insecure supply chain, and significant batch-to-batch variability. The use of animal-derived heparin also raises ethical and religious concerns, as well as carries the risk of transmitting zoonotic diseases. Chemoenzymatic synthesis of animal-free heparin products would offer several advantages, including reliable and scalable production processes, improved purity and consistency, and the ability to produce heparin polysaccharides with molecular weight, structural, and functional properties equivalent to those of the United States Pharmacopeia (USP) heparin, currently only sourced from porcine intestinal mucosa. We report a scalable process for the production of bioengineered heparin that is biologically and compositionally similar to USP heparin. This process relies on enzymes from the heparin biosynthetic pathway, immobilized on an inert support and requires a tailored N-sulfoheparosan with N-sulfo levels similar to those of porcine heparins. We also report the conversion of our bioengineered heparin into a LMWH that is biologically and compositionally similar to USP enoxaparin. Ultimately, we demonstrate major advances to a process to provide a potential clinical and sustainable alternative to porcine-derived heparin products.

Efficacy, safety, and feasibility of Apixaban for postoperative venous thromboembolism prophylaxis following open gynecologic cancer surgery at a comprehensive cancer center.

OBJECTIVES: To evaluate safety, efficacy, and feasibility of apixaban for postoperative venous thromboembolism (VTE) prophylaxis following open gynecologic cancer surgery at a comprehensive cancer center. METHODS: This retrospective, cohort study included patients with gynecologic cancer who underwent open surgery between 3/2021 and 3/2023 and received 28-day postoperative VTE prophylaxis. Patients on therapeutic anticoagulation preoperatively were excluded. Predictors of 90- and 30-day VTE and 30-day bleeding events were determined using multivariable logistic regression, adjusting for known confounders. RESULTS: 452 patients were included in the cohort: 348 received apixaban and 104 received enoxaparin. Those who received enoxaparin were more likely to be American Society of Anesthesiologists class III/IV (compared to I/II) (p = 0.033), current or former smokers (p = 0.012) and have a higher BMI (p < 0.001), Charlson Comorbidity Index (p = 0.005), and age (p = 0.046). 30-day VTE rate was significantly lower in the apixaban group (0.6%) compared to the enoxaparin group (6.2%) (adjusted OR 0.13, 95% CI 0.03-0.56; p = 0.006). 90-day VTE rate was 2.7% and 6.2% in the apixaban and enoxaparin groups, respectively (adjusted OR 0.85, 95% CI 0.38-1.92; p = 0.704). Major bleeding complications (2.4% vs. 2.0%) and minor bleeding complications (0.9% vs. 3.0%) were similar in the apixaban and enoxaparin groups, respectively, on multivariate analyses. The median patient out of pocket cost was $10 (IQR 0.0-40.0) for apixaban and $20 (IQR 3.7-67.7) for enoxaparin (p = 0.001). CONCLUSIONS: Our findings along with previously published data suggest that apixaban should be considered the standard of care for VTE prophylaxis in patients undergoing open surgery for gynecologic malignancies.

Enoxaparin treatment dosing for venous thromboembolism in pediatric patients with obesity.

BACKGROUND: The optimal enoxaparin dosing for treatment of venous thromboembolism (VTE) in pediatric patients with obesity remains uncertain. We described the mean enoxaparin dose required to attain anti-factor Xa (anti-Xa) levels of 0.5-1 unit/mL in pediatric patients with obesity. METHODS: Pediatric patients with obesity (body mass index [BMI] ≥95th percentile) who received treatment dose of enoxaparin from 2013 to 2022 and had at least one appropriately timed anti-Xa level were retrospectively evaluated. Daily enoxaparin dose required to achieve an anti-Xa level of 0.5-1 unit/mL was reviewed and compared by the severity of obesity. The correlation coefficients between enoxaparin dose requirement and BMI, BMI percentile, and weight were measured by Spearman's rank correlation coefficient. RESULTS: Pediatric patients with obesity (n = 89) required a mean enoxaparin dose of 0.8 ± 0.18 mg/kg twice daily to attain a therapeutic anti-Xa level. Children with BMI 95th-99th percentile and weight ≤100 kg achieved the target level on a significantly higher weight-based enoxaparin dose compared to BMI greater than 99th percentile (0.95 ± 0.15 vs. 0.75 ± 0.15 mg/kg twice daily; p < .001) and weight greater than 100 kg (0.95 ± 0.14 vs. 0.7 ± 0.12 mg/kg twice daily; p < .001). BMI, BMI percentile, and weight showed a moderate to strong negative correlation with enoxaparin dose requirement. CONCLUSIONS: Pediatric patients with obesity required a lower weight-based dose of enoxaparin to achieve a therapeutic anti-Xa than the recommended starting dose of 1 mg/kg twice daily for treatment of VTE. Among obesity indices, weight showed the strongest negative correlation with total daily enoxaparin requirement.

Enoxaparin thromboprophylaxis in hospitalized obese pediatric patients.

BACKGROUND: Enoxaparin is an anticoagulant used for pharmacologic thromboprophylaxis in pediatrics. Enoxaparin pharmacokinetics can be altered in the setting of obesity. Optimal enoxaparin dosing for thromboprophylaxis in children with obesity remains unclear. PROCEDURE: A retrospective review was conducted of pediatric patients who weighed ≥60 kg with BMI ≥ 95th percentile, received enoxaparin for thromboprophylaxis, and had at least one appropriately drawn anti-factor Xa (anti-Xa) from 2013 to 2022. Anti-Xa levels were reviewed for patients initially treated with enoxaparin 30 mg every 12 h. The average daily enoxaparin dose required to achieve an anti-Xa of 0.2-0.4 unit/mL, which was stratified by BMI percentile and weight, was calculated. RESULTS: Of 116 patients (median age 15.8 years) included for analysis, 106 patients were initially treated with enoxaparin 30 mg every 12 h. Anti-Xa levels were <0.2 unit/mL in 53% of patients with BMI > 99th percentile and 54% of patients >100 kg. Ninety-one patients had at least one anti-Xa 0.2-0.4 unit/mL with an average daily enoxaparin dosing of 66 mg. When stratified by severity of obesity, higher doses were required to attain an anti-Xa 0.2-0.4 unit/mL in patients with BMI > 99th percentile compared with those with 95th-99th percentile (67.8 ± 15.7 vs. 62 ± 5.6 mg/day, p = .01). Patients > 100 kg required significantly higher dose than those ≤100 kg (69.1 ± 15.5 vs 61.2 ± 7.3 mg/day, p = .002). CONCLUSIONS: Increased initial dosing and/or anti-Xa level monitoring should be considered in adolescents with severe obesity receiving enoxaparin thromboprophylaxis.

Interaction of heparin with human cardiac troponin complex and its influence on the immunodetection of troponins in human blood samples.

OBJECTIVES: Heparin is a highly charged polysaccharide used as an anticoagulant to prevent blood coagulation in patients with presumed myocardial infarction and to prepare heparin plasma samples for laboratory tests. There are conflicting data regarding the effects of heparin on the measurement of cardiac isoforms of troponin I (cTnI) and troponin T (cTnT), which are used for the immunodiagnosis of acute myocardial infarction. In this study, we investigated the influence of heparin on the immunodetection of human cardiac troponins. METHODS: Gel filtration (GF) techniques and sandwich fluoroimmunoassay were performed. The regions of сTnI and cTnT that are affected by heparin were investigated with a panel of anti-cTnI and anti-cTnT monoclonal antibodies, specific to different epitopes. RESULTS: Heparin was shown to bind to the human cardiac full-size ternary troponin complex (ITC-complex) and free cTnT, which increased their apparent molecular weights in GF studies. Heparin did not bind to the low molecular weight ITC-complex and to binary cTnI-troponin С complex. We did not detect any sites on cTnI in the ITC-complex that were specifically affected by heparin. In contrast, cTnT regions limited to approximately 69-99, 119-138 and 145-164 amino acid residues (aar) in the ITC-complex and a region that lies approximately between 236 and 255 aar of free cTnT were prone to heparin influence. CONCLUSIONS: Heparin binds to the ITC-complex via cTnT, interacting with several sites on the N-terminal and/or central parts of the cTnT molecule, which might influence the immunodetection of analytes in human blood.

Risk Stratification for Supratherapeutic Peak Anti-Xa Levels in Adult Patients on Therapeutic Enoxaparin.

BACKGROUND: The American Society of Hematology Guidelines for the management of venous thromboembolism recommend against the use of anti-Xa monitoring for assessing enoxaparin dosing based on a low level of evidence associating supratherapeutic levels with an increased risk of bleeding. However, institutions still utilize anti-Xa levels in select patient populations with altered volume of distribution and/or excretion to monitor and adjust therapy. OBJECTIVE: The primary objective of this study was to identify risk factors associated with supratherapeutic peak anti-Xa levels (≥1.10 IU/mL) for patients receiving therapeutic enoxaparin. METHODS: This was a retrospective single-center study performed at an academic tertiary care hospital. Patients who received enoxaparin at 1 mg/kg twice daily and peak anti-Xa monitoring were separated into supratherapeutic and therapeutic/subtherapeutic cohorts. RESULTS: A total of 436 patients were screened, and 215 were included, with a mean age of 62 years. There were 108 in the therapeutic/subtherapeutic cohort and 107 in the supratherapeutic cohort. Acute kidney injury (AKI), body mass index (BMI), weight, female sex, intensive care unit (ICU) service, Sequential Organ Failure Assessment (SOFA) score ≥4, and creatinine clearance at the time of peak anti-Xa level collection were associated with supratherapeutic anti-Xa levels in univariate models. Adjusted logistic regression models were created and identified BMI in the 30 to 34.9 kg/m2 (odds ratio [OR] 4.35; 95% confidence interval [CI] 1.70-11.13, P < 0.005) and ≥35 kg/m2 (OR 6.75; 95% CI 3.05-14.94, P < 0.005) and AKI (OR 2.62; 95% CI 1.04-6.62, P = 0.042) as significant risk factors for supratherapeutic anti-Xa levels. CONCLUSION AND RELEVANCE: Our study identified BMI ≥ 30 kg/m2, AKI, female sex, ICU service, SOFA score ≥4, and creatinine clearance as risk factors for supratherapeutic anti-Xa levels in patients receiving 1 mg/kg twice daily dosing of enoxaparin. Further research should be done to provide evidence for the association between anti-Xa levels and bleeding risk.

Prophylaxis with enoxaparin and antithrombin III in drug-induced coagulation alterations in childhood leukemia: a retrospective experience of 20 years.

BACKGROUND: Thromboembolic complications are well known in the treatment of childhood acute lymphoblastic leukemia. Over the years it has not been possible to reach a consensus on a possible prophylaxis of thromboembolic events during intensive therapy. Only the administration of enoxaparin was able to achieve evidence in the literature to date. METHODS: In this retrospective study, 173 childhood leukemia patients were treated over 20 years with a thromboembolic prophylaxis including enoxaparin and AT III during induction therapy with L-asparaginase and cortisone. RESULTS: We here report the effectiveness of administration of enoxaparin and AT III in childhood leukemia, showing a strikingly low prevalence of deep vein thrombosis (2.9%). Especially in adolescent patients, a particularly great need for AT III was demonstrated. CONCLUSIONS: We recommend thromboembolic prophylaxis with enoxaparin and AT III substitution during induction/reinduction therapy with L-asparaginase and glucocorticosteroids, especially from adolescence onwards.

The effects of enoxaparin treatment in a xenograft mouse model of oral squamous cell carcinoma: A pilot study.

BACKGROUND: Recent studies suggest that enoxaparin may have therapeutic effects on oral squamous cell carcinoma. We aimed to assess this effect utilizing xenograft mouse model through evaluations of proliferation and angiogenesis markers at the RNA and protein levels. METHODS: Mice were divided into enoxaparin treatment (n = 4), positive control (n = 4) and negative control (n = 3) groups. Immunohistochemical analyses were performed utilizing Bcl-2, Bax and Ki-67 antibodies. Expression levels of proliferation and apoptosis related genes were calculated utilizing qRT-PCR. Time-dependent proliferation assays were performed in OSC-19 and HEK293 cell-lines. RESULTS: Bax antibody showed positive staining in the cytoplasm and nuclei of tumor cells, while Bcl-2 antibody displayed staining only in the cytoplasm. A proliferation index of 15%-20% was found in all groups with the Ki-67 marker indicating no metastasis. Enoxaparin treatment caused decrease in BCL2, BAX and CCNB1 genes' expressions. Compared to HEK293, proliferation assays demonstrated higher division rates in OSC-19 with a significant decrease in viability after 96 h. CONCLUSION: Reduced BCL-2 expression indicates a regression of tumor growth, but reduced BAX expression is not correlated with increased apoptosis. Despite the aggressive nature of OSC-19, our results showed a low cell viability with a high division rate when compared with the control HEK293. This paralleled our in vivo findings that showed absence of lymph node metastasis across all mice groups. This discrepancy with the literature suggests that further investigations of the underlying mechanisms and protein-level analyses are needed to draw definitive conclusions about the effect of enoxaparin on OSC-19 behavior.

Venous Thromboembolism Prophylaxis in Low Body Weight Critically Ill Patients.

OBJECTIVE: To compare bleeding and thromboembolic events in low body weight patients receiving reduced-dose venous thromboembolism (VTE) prophylaxis versus standard-dose VTE prophylaxis. DESIGN: Multicenter, retrospective, cohort study. SETTING: Five Ascension Health Hospitals. PATIENTS: Adult, critically ill, low body weight (≤50 kg) patients who received either reduced-dose VTE prophylaxis (n = 140) or standard-dose VTE prophylaxis (n = 279) for at least 48 h. INTERVENTION: Reduced-dose prophylaxis (enoxaparin 30 mg daily or heparin 5000 units every 12 h subcutaneously) or standard-dose prophylaxis (enoxaparin 40 mg daily, enoxaparin 30 mg every 12 h, or heparin 5000 units every 8 h subcutaneously). MEASUREMENTS AND MAIN RESULTS: A total of 419 patients were included with a mean weight of 45.1 ± 4.2 kg in the standard-dose group and 44.0 ± 5.1 kg in the reduced-dose prophylaxis group (P = .02). The primary endpoint, composite bleeding, was significantly lower in patients receiving reduced-dose prophylaxis (5% vs 12.5%, P = .02). After adjusting for confounding factors, results remained consistent demonstrating reduced composite bleeding with reduced-dose prophylaxis (odds ratio: 0.36, 95% confidence interval: 0.14-0.96). Major bleeding events occurred in 3.6% of reduced-dose patients compared with 8.6% in standard-dose patients (P = .056). Clinically relevant nonmajor bleeding (5.4% vs 2.9%, P = .24) and VTE (2.2% vs 0%, P = .08) events were similar between groups. CONCLUSIONS: A reduced-dose VTE prophylaxis strategy in low body weight, critically ill patients was associated with a lower risk of composite bleeding and similar rate of thromboembolism.

Incidence of Symptomatic Venous Thromboembolisms in Stroke Patients.

Venous thromboembolism (VTE) is a common but preventable complication observed in critically ill patients. Deep vein thrombosis (DVT) is the most common type of VTE, with clinical significance based on location and symptoms. There is an increased incidence of DVT and pulmonary embolism (PE) in ischemic stroke patients using unfractionated heparin (UFH) for VTE prophylaxis compared with those using enoxaparin. However, UFH is still used in some patients due to its perceived safety, despite conflicting literature suggesting that enoxaparin may have a protective effect. The current study aimed to determine the incidence of VTEs in patients with acute ischemic strokes on UFH versus enoxaparin for VTE prophylaxis, subclassifying the VTEs depending on their location and symptoms. It also aimed to examine the safety profile of both drugs. A total of 909 patients admitted to the Neuro-ICU with the diagnosis of acute ischemic stroke were identified, and 634 patients were enrolled in the study-170 in the enoxaparin group and 464 in the UFH group-after applying the exclusion criteria. Nineteen patients in the UFH group (4.1%) and 3 patients in the enoxaparin group (1.8%) had a VTE. The incidence of DVT in the UFH group was 12 (2.6%), all of which were symptomatic, compared with 3 (1.8%) in the enoxaparin group, wherein one case was symptomatic. Nine patients (1.9%) in the UFH group developed a PE during the study period, and all of them were symptomatic. No patients in the enoxaparin group developed PE. No statistically significant difference was found between both groups. However, 18 patients in the UFH group (3.9%) experienced intracranial hemorrhage compared with none in the enoxaparin group, and this difference was statistically significant. Enoxaparin was found to be as effective as and potentially safer than UFH when used for VTE prophylaxis in stroke patients.

Structured benefit-risk assessment for enoxaparin, in the context of its label extension, for the extended treatment of deep vein thrombosis and pulmonary embolism, and prevention of its recurrence in patients with active cancer.

PURPOSE: Guidelines recommend low-molecular-weight heparins (LMWHs) for patients with cancer-associated thrombosis. However, until recently, only dalteparin and tinzaparin were approved in the European Economic Area (EEA) for these patients. This study compares the benefit-risk profile of enoxaparin with dalteparin and tinzaparin for the extended treatment of deep vein thrombosis (DVT) and pulmonary embolism (PE), and prevention of recurrence in adult patients with active cancer. METHODS: A semi-quantitative structured benefit-risk assessment was conducted for the label-extension application of enoxaparin based on the benefit-risk action team descriptive framework: define decision context; determine key benefit and risk outcomes; identify data sources; extract data; interpret results. RESULTS: The key benefits were defined as reduced all-cause mortality and venous thromboembolism (VTE) recurrence (including symptomatic DVT, fatal PE or non-fatal PE); the key risks were major and non-major bleeding of clinical significance, and heparin-induced thrombocytopenia (HIT). Enoxaparin demonstrated comparable effects for the reduction of VTE recurrence and all-cause mortality versus other EEA-approved LMWHs (dalteparin, tinzaparin). There was no evidence of a significant difference between enoxaparin and the comparator groups with regard to incidence of major and non-major bleeding. The data on HIT were too limited to assess the difference between the two groups. CONCLUSIONS: The assessment demonstrated a favourable benefit-risk profile for enoxaparin similar to that of other EEA-approved LMWHs for the treatment of DVT and PE and the prevention of recurrence in patients with active cancer and thus supported the label-extension approval.

Effect of Enoxaparin and Daikenchuto Coadministration on Hepatic Disorder Markers in Gynecological Cancer Patients after Abdominal Surgery.

Enoxaparin and daikenchuto are commonly administered to prevent venous thromboembolism and intestinal obstruction after gynecological malignancy surgery. However, the effects of their combined use on hepatic function are not well studied. This study aimed to clarify the effects of the coadministration of enoxaparin and daikenchuto on hepatic function. First, Japanese Adverse Drug Event Report (JADER) data were analyzed to identify signals of hepatic disorders. Second, a retrospective observational study of patients who underwent surgery for gynecological malignancies was conducted. This study defined hepatic disorders as an increase in aspartate aminotransferase (AST) or alanine aminotransaminase (ALT) levels above the reference values, using 1-h postoperative values as the baseline. The analysis of JADER data revealed an increased risk for hepatic disorders with the coadministration of enoxaparin and daikenchuto. An observational study also showed higher odds ratios (95% confidence intervals) for the occurrence of hepatic disorders in the coadministration group (4.27; 2.11-8.64) and enoxaparin alone group (2.48; 1.31-4.69) than in the daikenchuto alone group. The median increase in the ALT level was also higher in the coadministration group (34; 15-59) than in the enoxaparin alone (19; 6-38) and daikenchuto alone groups (8; 3-33). In conclusion, our study suggests that compared with the use of enoxaparin or daikenchuto alone, enoxaparin and daikenchuto coadministration increases the risk of hepatic disorders, with more significant increases in AST and ALT levels. Healthcare workers need to be aware of these potential side effects when combining these drugs after surgery for gynecological malignancies.

A systematic review of therapeutic enoxaparin dosing in obesity.

Enoxaparin is a hydrophilic drug with obesity having little effect on its apparent volume of distribution, therefore patients with obesity receiving standard 1 mg/kg dosing may be at a higher risk of supratherapeutic dosing. Conversely, dose reducing patients with obesity could place already at risk patients at higher risk of a thrombotic event. Data and recommendations are variable for the most appropriate weight-based dose of therapeutic enoxaparin in obese patients, particularly those a weight > 100 kg or a body mass index (BMI) ≥ 40 kg/m2. The purpose of this systematic review was to globally evaluate these data to surmise optimal dosing recommendations for patients with obesity. A systematic review of English language studies was conducted and identified articles via Pubmed, EMBASE, and the Cochrane Central Register of Controlled Trials (CENTRAL) searches. Studies were included if they reported therapeutic enoxaparin use in adult patients with a BMI ≥ 40 kg/m2 or body weight > 100 kg and the percentage of patients achieving a therapeutic anti-Xa based on a weight-based dose or the weight-based dose required to produce a therapeutic anti-Xa level. Therapeutic attainment of anti-Xa levels were assessed across enoxaparin weight-based dosing categories including a very low dose group: < 0.75 mg/kg, low dose group: 0.75-0.85 mg/kg, and standard dose group: ≥ 0.95 mg/kg. Rates of bleeding and thrombosis were also evaluated. A total of eight studies were included. For anti-Xa level assessment, 682 patients were included. A total of 62% of anti-Xa levels were therapeutic in the very low dose group, 66% in the low dose group, and 42% in the standard dose group. Overall rates of total bleeding and thrombosis were assessed in 798 patients. A total of 29 bleedings (3.6%) occurred, and 27 reported a relationship to dose. Most bleedings, 85.2% (n = 23/27), occurred with doses in the standard dose group (≥ 0.95 mg/kg). Thrombosis occurred in 5 patients (0.6%). Utilization of a reduced weight-based dosing strategy for therapeutic enoxaparin in obese patients may increase the percentage of patients with a therapeutic anti-Xa level.

Investigation of the effects of treatment with enoxaparin sodium and hyperbaric oxygen therapy on the recovery of rats with achilles tendon rupture.

PURPOSE: In this study, we aimed to investigate the effects of hyperbaric oxygen therapy and enoxaparin sodium, which are known to accelerate bone tissue healing as well as tendon and soft tissue healing, on the healing of Achilles tendon rupture. METHODS: Thirty-six rats were used in the present study. All rats were divided into groups of nine. The groups were the enoxaparin sodium group, enoxaparin sodium and hyperbaric oxygen group, hyperbaric oxygen group and control group. After 21 days, the process was completed, and the rats were sacrificed. Achilles tendon samples were evaluated histopathologically. RESULTS: The groups were compared according to the results of statistical analysis based on the histopathological data. There was no significant difference between the groups in terms of acute inflammation (p = 0.785) or chronic inflammation (p = 0.827) scores, but there were significant differences in neovascularization (p = 0.009), proliferation (p < 0.001) and fibrosis (p = 0.006) scores. CONCLUSION: Our study showed that the use of enoxaparin sodium and hyperbaric oxygen had a positive effect on the healing of the Achilles tendon. Based on these results, we believe that the use of enoxaparin sodium and hyperbaric oxygen therapy after Achilles tendon rupture will be beneficial for healing and preventing complications.

Pharmacologic Venous Thromboembolism Prophylaxis in Patients with Nontraumatic Subarachnoid Hemorrhage Requiring an External Ventricular Drain.

BACKGROUND: Optimal pharmacologic thromboprophylaxis dosing is not well described in patients with subarachnoid hemorrhage (SAH) with an external ventricular drain (EVD). Our patients with SAH with an EVD who receive prophylactic enoxaparin are routinely monitored using timed anti-Xa levels. Our primary study goal was to determine the frequency of venous thromboembolism (VTE) and secondary intracranial hemorrhage (ICH) for this population of patients who received pharmacologic prophylaxis with enoxaparin or unfractionated heparin (UFH). METHODS: A retrospective chart review was performed for all patients with SAH admitted to the neurocritical care unit at Emory University Hospital between 2012 and 2017. All patients with SAH who required an EVD were included. RESULTS: Of 1,351 patients screened, 868 required an EVD. Of these 868 patients, 627 received enoxaparin, 114 received UFH, and 127 did not receive pharmacologic prophylaxis. VTE occurred in 7.5% of patients in the enoxaparin group, 4.4% in the UFH group (p = 0.32), and 3.2% in the no VTE prophylaxis group (p = 0.08). Secondary ICH occurred in 3.83% of patients in the enoxaparin group, 3.51% in the UFH group (p = 1), and 3.94% in the no VTE prophylaxis group (p = 0.53). As steady-state anti-Xa levels increased from 0.1 units/mL to > 0.3 units/mL, there was a trend toward a lower incidence of VTE. However, no correlation was noted between rising anti-Xa levels and an increased incidence of secondary ICH. When compared, neither enoxaparin nor UFH use was associated with a significantly reduced incidence of VTE or an increased incidence of ICH. CONCLUSIONS: In this retrospective study of patients with nontraumatic SAH with an EVD who received enoxaparin or UFH VTE prophylaxis or no VTE prophylaxis, there was no statistically significant difference in the incidence of VTE or secondary ICH. For patients receiving prophylactic enoxaparin, achieving higher steady-state target anti-Xa levels may be associated with a lower incidence of VTE without increasing the risk of secondary ICH.

Update on the Pharmacological Actions of Enoxaparin in Nonsurgical Patients.

Low-molecular-weight heparins are a class of drugs derived from the enzymatic depolymerization of unfractionated heparin that includes enoxaparin. Several studies have been performed on enoxaparin in recent years, in particular for the prevention and treatment of venous thromboembolism and for the treatment of acute coronary syndrome. Furthermore, the use of enoxaparin has been extended to other clinical situations that require antithrombotic pharmacological prevention, such as hemodialysis and recurrent abortion. In this review, we report the main clinical experiences of using enoxaparin in the prevention of VTE in nonsurgical patients.

Enoxaparin sodium combined with magnesium sulfate in the treatment of severe preeclampsia.

Objective: To observe the treatment of severe preeclampsia in newborns with enoxaparin sodium combined with magnesium sulfate. Methods: A retrospective analysis was conducted on the clinical data of 80 patients with severe preeclampsia admitted to Hefei Second People's Hospital, China from January 2019 to December 2020. Treatment records showed that 40 cases received magnesium sulfate treatment (single group), and 40 cases received enoxaparin sodium combined with magnesium sulfate treatment (combination group). Levels of D-dimer, soluble fms-like tyrosine kinase 1 (sFlt-1), placental growth factor (PLGF), Apgar scores of newborns delivered before and after treatment were compared. Gestation weeks and incidence of adverse reactions were analyzed. Results: After treatment, levels of D-dimer, sfit-1 and adverse reactions in the combination group were significantly lower than those in the single group (P<0.05), and the level of PLGF, newborn Apgar score and length of gestation were significantly higher than those in the single group (P<0.05). Conclusion: Compared to magnesium sulfate alone, the combination of enoxaparin sodium and magnesium sulfate in the treatment of pregnant women with severe preeclampsia can more effectively regulate the cytokine level of patients, improve pregnancy outcome, and improve neonatal Apgar score. The incidence of adverse reactions is low, making it a safe and efficient treatment modality.

Impact of Reduced Enoxaparin Prophylactic Dosing on Bleeding and Thrombotic Risk for Low Body Weight Post-Operative Colorectal Surgery Patients.

Introduction: Colorectal surgery (CORS) patients are at the highest risk of any general surgery population for the development of post-operative venous thromboembolism (VTE) and are also at an increased risk for post-operative bleeding, especially with procedures related to early cancer stages. Low molecular weight heparin (LMWH) is recommended for VTE prophylaxis in this surgical population. Current guidelines and primary literature along with institutional protocols support dosage adjustments for obesity and impaired renal function, but literature providing optimal VTE prophylactic LMWH dosing is extremely limited for underweight, surgical patients. Objectives: The aim of this study was to evaluate both bleeding and VTE rates for hospitalized underweight colorectal surgery patients receiving post-operative VTE prophylaxis with standard enoxaparin 40 mg subcutaneously (SQ) every 24 hours versus reduced dose enoxaparin 30 mg SQ every 24 hours. Methods: This trial was a multicenter, retrospective chart review with data collected on post-operative CORS patients over a 10-year period. Patients were included if aged 18 years and older, weighed less than 50 kg, and received at least 1 dose of enoxaparin 40 mg or 30 mg post-operatively. The primary endpoint was a descriptive comparison of post-operative bleeding with use of standard enoxaparin 40 mg SQ every 24 hours compared to reduced dose enoxaparin 30 mg SQ every 24 hours for post-operative VTE prophylaxis. The secondary endpoint was the descriptive comparison of post-operative thrombotic event rates in the same population. Results: The total population investigated included 146 patients. One hundred twenty-nine (88.4%) received standard enoxaparin and 17 (11.6%) received reduced enoxaparin. Overall, 9 bleeding events (7.0%) and 2 major VTE events (1.6%) occurred, all within the standard enoxaparin group. Conclusion: Standard dose enoxaparin for post-operative VTE prophylaxis demonstrated increased bleeding and thrombotic events requiring medical and surgical intervention in comparison to reduced dose enoxaparin for low body weight CORS patients. The results of this study are hypothesis generating and continued research involving more robust systematic reviews are needed to evaluate both safety and efficacy of reduced VTE prophylaxis with LMWH in the underweight, surgical patient population.

Effect of Enoxaparin on D-dimer levels in hospitalized Corona Virus patients with a comparison of its level in patients with comorbid conditions.

OBJECTIVE: Aim: The main goal is to assess the levels of comorbid diseases and examine the changes in D-dimer in hospitalized patients before and following SC enoxaparin medication. PATIENTS AND METHODS: Material and Methods: At the Al-Yarmouk Teaching Hospital in Baghdad, Iraq, from October 2022 to May 2023, 86 patients who were hospitalized and had severe to critical COVID-19 infections provided data for a retrospective analysis. RESULTS: Results: The medical records of all COVID-19 patients who were hospitalized and whose D-dimer level was greater than 0.5 mg/l and who were given enoxaparin (40 mg subcutaneously) were reviewed with the requisite authorization from the relevant authorities. The D-dimer level was assessed following therapy on the day of admission and day five after commencing enoxaparin. An examination of 86 case records revealed that persons with COVID-19 had significantly decreased D-dimer levels after taking subcutaneous enoxaparin (p-value<0.0001). The comorbidities (diabetes mellitus, hypertension) of patients who received the drug were compared. CONCLUSION: Conclusions: Enoxaparin and other anticoagulants were utilized to treat the coagulopathy brought on by COVID-19. Low molecular weight heparin enoxaparin has demonstrated positive outcomes in the management of VTE. A decrease in D-dimer level is anticipated when COVID-19 patients are treated with subcutaneous enoxaparin, partly because decreased coagulation results in lower fibrin formation.

Aspirin prophylaxis is not associated with increased risk of venous thromboembolism in arthroplasty for femoral neck fractures: a non-inferiority study.

PURPOSE: Venous thromboembolism (VTE) is a known complication of hip arthroplasty for femoral neck fractures (FNF) with various prophylactic anticoagulants utilized to decrease risk. The purpose of this study was to assess the efficacy and perioperative outcomes associated with aspirin for VTE prophylaxis following arthroplasty for FNF. METHODS: Medical records of 1,220 patients who underwent hip hemiarthroplasty (HHA) or total hip arthroplasty (THA) at an urban academic center from 2011 to 2022 were retrospectively reviewed. Patient characteristics and perioperative outcomes, including length of stay (LOS), VTE, 90-day hospital encounters, and discharge disposition, were collected. Outcomes for patients prescribed aspirin (n = 214) were compared to those prescribed non-aspirin VTE prophylaxis (n = 1006) using propensity score matching. RESULTS: Patients who received aspirin had higher rates of THA (36.0 vs 26.7%; p = 0.008). There were no significant risk-adjusted differences in the incidence of VTE (0.5 vs 0.5%, p = 1.000) and 90-day readmissions (10.4 vs 12.3%, p = 0.646) between patients prescribed aspirin and non-aspirin VTE prophylaxis, respectively. Patients prescribed non-aspirin agents had higher rates of non-home discharge (73.9 vs 58.5%; p < 0.001) and longer LOS (143.5 vs 124.9 h; p = 0.005). Sub-analysis of patients prescribed aspirin and non-aspirin prophylaxis based on comorbidity scores demonstrated no difference in VTE incidence for low (0.0 vs 1.6%, p = 1.000) and high scores (0.0 vs 0.0%, p = 1.000), respectively. CONCLUSION: Aspirin is not associated with increased incidence of VTE after HHA or THA for FNF. Aspirin prophylaxis should be considered in hip fracture patients to mitigate bleeding risk, particularly those with low to intermediate VTE risk. LEVEL OF EVIDENCE: Level III, Retrospective study.