Subcutaneous Unfractionated Heparin Research Articles

Propensity weighted analysis of chemical venous thromboembolism prophylaxis agents in isolated severe traumatic brain injury: An EAST sponsored multicenter study

BackgroundIn patients with severe traumatic brain injury (TBI), clinicians must balance preventing venous thromboembolism (VTE) with the risk of intracranial hemorrhagic expansion (ICHE). We hypothesized that low molecular weight heparin (LMWH) would not increase risk of ICHE or VTE as compared to unfractionated heparin (UH) in patients with severe TBI. MethodsPatients ≥ 18 years of age with isolated severe TBI (AIS ≥ 3), admitted to 24 level I and II trauma centers between January 1, 2014 to December 31, 2020 and who received subcutaneous UH and LMWH injections for chemical venous thromboembolism prophylaxis (VTEP) were included. Primary outcomes were VTE and ICHE after VTEP initiation. Secondary outcomes were mortality and neurosurgical interventions. Entropy balancing (EBAL) weighted competing risk or logistic regression models were estimated for all outcomes with chemical VTEP agent as the predictor of interest. Results984 patients received chemical VTEP, 482 UH and 502 LMWH. Patients on LMWH more often had pre-existing conditions such as liver disease (UH vs LMWH 1.7 % vs. 4.4 %, p = 0.01), and coagulopathy (UH vs LMWH 0.4 % vs. 4.2 %, p < 0.001). There were no differences in VTE or ICHE after VTEP initiation. There were no differences in neurosurgical interventions performed. There were a total of 29 VTE events (3 %) in the cohort who received VTEP. A Cox proportional hazards model with a random effect for facility demonstrated no statistically significant differences in time to VTE across the two agents (p = 0.44). The LMWH group had a 43 % lower risk of overall ICHE compared to the UH group (HR = 0.57: 95 % CI = 0.32–1.03, p = 0.062), however was not statistically significant. ConclusionIn this multi-center analysis, patients who received LMWH had a decreased risk of ICHE, with no differences in VTE, ICHE after VTEP initiation and neurosurgical interventions compared to those who received UH. There were no safety concerns when using LMWH compared to UH. Level of evidenceLevel III, Therapeutic Care Management

Elevated Anti-Xa in the Setting of Prophylactic Unfractionated Subcutaneous Heparin Administration.

Venous thromboembolism prophylaxis with subcutaneous unfractionated heparin or low molecular weight heparin is a common practice in hospitalized patients. Typically, prophylactic doses of these medications have poor bioavailability and thus do not reach therapeutic serum concentrations. However, in certain circumstances, heparin binding proteins may become saturated. Here we report a case series of 5 patients who had elevated anti-Xa levels while receiving prophylactic dosing of subcutaneous unfractionated heparin.

Venous thromboembolic disease in admitted blunt trauma patients: what matters?

BackgroundVenous thromboembolic events (VTE) are a significant cause of morbidity and mortality following traumatic injury. We examined demographic characteristics, chemoprophylaxis, and outcomes of VTE patients with blunt trauma requiring hospitalization.MethodsA retrospective review of adult blunt trauma hospitalizations with and without VTE between 2012 and 2019 was conducted. Deaths in the emergency department were excluded. Univariate and multivariable analyses, including machine learning classification algorithms for VTE, were performed.ResultsOf 10,926 admitted adult blunt trauma patients, 177 had VTE events. VTE events occurred at a median of 6 [IQR 3–11] days, with 7.3% occurring within 1 day of admission. VTE patients were more often male, and more often underwent surgery. They had higher injury severity as well as longer intensive care unit and hospital lengths of stay. While VTE occurred throughout the spectrum of injury severity, 27.7% had low injury severity (ISS < = 9). In multivariable analyses, both heparin and enoxaparin had reduced adjusted odds ratios for VTE.ConclusionApproximately 7.3% of VTE events occurred within one day of admission. A substantial proportion of VTE events occurred in patients with low injury severity (ISS < = 9). Subcutaneous unfractionated heparin and enoxaparin chemoprophylaxis were both inversely associated with VTE. These findings underscore the need for vigilance for VTE identification in blunt trauma patients throughout their hospitalization and VTE prevention efforts.

PB0511 Safety and Efficacy of Therapeutic Anticoagulation with Subcutaneous Unfractionated Heparin in Patients with Renal Failure

PB0511 Safety and Efficacy of Therapeutic Anticoagulation with Subcutaneous Unfractionated Heparin in Patients with Renal Failure

Safety and Efficacy of Therapeutic Anticoagulation with Subcutaneous Unfractionated Heparin in Patients with Renal Failure.

Safety and Efficacy of Therapeutic Anticoagulation with Subcutaneous Unfractionated Heparin in Patients with Renal Failure.

Assessment of bleeding risk in low-weight patients receiving prophylactic subcutaneous unfractionated heparin.

Underweight patients may be at an increased risk of bleeding while receiving venous thromboembolism (VTE) prophylaxis. Additional evidence is needed to identify patient-specific factors associated with bleeding. The objective of the study was to describe the incidence and identify risk factors associated with bleeding in low-weight (⩽ 60 kg) adult patients receiving subcutaneous unfractionated heparin (SQH) for VTE prophylaxis. This was a single-center, retrospective, nested case-control study of low-weight patients receiving SQH for VTE prophylaxis for ⩾ 48 hours. Cases, patients with clinically relevant bleeding while receiving SQH, and controls, patients without a bleeding event, were matched in a 1:3 ratio for age, sex, primary service (surgical or medical), and time at risk of bleeding on SQH to determine factors associated with bleeding. A total of 3761 patients met the inclusion criteria, of which 38 cases of clinically relevant bleeding were identified. The bleeding incidence was 1% at hospital day 6 and 2.8% at hospital day 14. Most patients in this study (69%) received SQH 5000 units three times daily. ICU admission at SQH start was associated with bleeding, OR 2.97 (95% CI 1.21-7.29). Bleeding in low-weight patients on prophylactic SQH was uncommon. Patients admitted to the ICU at time of SQH start may be at a higher risk of bleeding. Further studies are needed to detect additional risk factors associated with bleeding and investigate the effects of reduced dosing in this population.

Increased bleeding risk with enoxaparin venothromboembolism prophylaxis compared with heparin in patients undergoing bariatric surgery.

Perioperative venothromboembolism (VTE) chemoprophylaxis is an established tenant of bariatric surgery; however, there is little comparative data to guide medication choice. The objective of this study was to determine if a change in VTE prophylaxis from heparin to enoxaparin was associated with differing rates of postoperative bleeding and VTE occurrence after bariatric surgery. This retrospective cohort study included patients 18years or older who underwent primary bariatric surgery (sleeve gastrectomy (SG) or Roux-en-Y gastric bypass (RYGB)) at a single institution between March 2012 and December 2021. Subcutaneous unfractionated heparin was utilized for VTE prophylaxis from March 2012 through February 2018 and then enoxaparin was used from March 2018 through December 2021. Postoperative bleeding was defined as requiring a blood transfusion or reoperation for bleeding within 30days of surgery. Chi-square test was used to test for differences between groups. There were 2159 patients who underwent bariatric surgery with 1324 (61.3%) patients in the heparin group and 835 (38.7%) in the enoxaparin group. Overall, 1,503 (69.6%) patients underwent SG and 656 (30.4%) RYGB. There was no difference in the ratio of SG to RYGB between the heparin and enoxaparin groups. Most patients were female (n = 1709, 79.2%) with a median age of 43.2years (interquartile range (IQR): 35.6-52.2), and median BMI of 44.9 (IQR: 40.9-50.5). Overall postoperative bleeding occurred more frequently in the enoxaparin group (n = 26, 3.1%) compared with the heparin group (n = 12, 0.9%) (p < 0.01). Additionally, reoperation for bleeding was more frequent with enoxaparin (enoxaparin 0.8% vs. heparin 0.2%, p = 0.04). There was no difference in VTE occurrence between the two groups (heparin: n = 14, 1.1%, enoxaparin: n = 7, 0.8% (p = 0.61)). An institutional change from heparin to enoxaparin for bariatric surgery perioperative VTE prophylaxis was associated with a significant increase in postoperative bleeding, with no difference in VTE complications.

Concordance Between Active Partial Thromboplastin Time and Anti-Factor Xa Assays in Neurocritically Ill Patients Receiving Subcutaneous Heparin Prophylaxis.

Laboratory monitoring is not recommended when subcutaneous unfractionated heparin (SQ-UFH) is administered at prophylactic doses. However, aPTT prolongation and associated hemorrhage has been reported in the neurocritically ill. At our institution, Neuroscience Intensive Care Unit (Neuro-ICU) patients with prolonged aPTT are further evaluated with a follow up aPTT and anti-factor Xa. The purpose of this study was to describe concordance between aPTT and anti-factor Xa in neurocritically ill patients receiving prophylactic SQ-UFH with evidence of aPTT prolongation. A retrospective chart review of adult patients admitted to the Neuro-ICU from June 2017 to June 2019 was performed. Patients were included if they received SQ-UFH with aPTT levels and at least one anti-factor Xa level drawn within one hour of each other. Concordance between paired aPTT and anti-factor Xa was evaluated using Cohen's weighted kappa. Forty two patients with 56 paired aPTT and anti-factor Xa levels were included. The most prescribed SQ-UFH regimen was 5000 units every 8 hours (60.7%) and anti-factor Xa levels were drawn a median (IQR) of 5.7 (3.1-10.7) hours after the SQ-UFH dose. Only 16 (28.6%) pairs were in concordance. The analysis showed a weighted kappa of .09; 95% CI [-.05 to .22] indicating poor agreement. In neurocritically ill patients receiving prophylactic SQ-UFH with aPTT prolongation, there was poor concordance between aPTT and anti-factor Xa. This suggests that aPTT prolongation may not be solely driven by heparin activity and further evaluation of mechanistic drivers for coagulopathy in this population is necessary.

Varying Dosages of Subcutaneous Unfractionated Heparin and Activated Partial Thromboplastin Time in Hospitalized Antepartum Patients: A Retrospective Cohort Analysis

(Anesth Analg. 2022;134:1028–1034. doi: 10.1213/ANE.0000000000005866) Approximately 10% of all maternal deaths in the United States are from venous thromboembolism (VTE). Clinical guidelines have been put into place, including what to administer antepartum patients with history of VTE who require an empiric pharmacologic prophylaxis. The recommended dosage for subcutaneous unfractionated heparin (UFH) corresponds to gestational age: 5000 to 7500 units every 12 hours for first trimester, 7500 to 10,000 units every 12 hours for second trimester, and 10,000 units every 12 hours for third trimester antepartum patients. The increased dosage is due to changing distribution volume, bioavailability, clearance, and metabolism during pregnancy. These clinical guideline adjustments may impact anesthetic use during labor and cesarean delivery, as UFH potentially inhibits coagulation, increases activated partial thromboplastin time (aPTT), and subsequently increases the risk of neuraxial hematoma associated with neuraxial anesthesia. The primary aim of this study was to determine the effect UFH has on coagulation by assessing what proportion of hospitalized antepartum women with aPTT over 40 seconds following subcutaneous UFH. The secondary aim was to identify the association between aPTT over 40 seconds and other risk factors.

Urticarial Rash in a Patient with Alpha-Gal Syndrome Caused by Subcutaneous Heparin at Prophylactic Dosing: A Case Report

Introduction: We report a patient with a history of red meat allergy, or alpha-gal syndrome, who had an urticarial rash after exposure to unfractionated heparin at a dose typically used for prophylaxis of deep venous thrombosis. Although anaphylactic reactions have been reported with systemic intravenous heparin, we believe this case is the first report of an immunoglobulin E–mediated reaction to subcutaneous heparin at prophylactic dosing. Clinical Findings: An 85-year-old male had a 3-year history of red meat allergy and was intolerant of pork and beef. He developed an immunoglobulin E–mediated allergic reaction to subcutaneous heparin at a dose of 5000 units twice daily. Clinical Course: The patient presented to the emergency department after a fall. He had back pain and was diagnosed with a compression fracture. He was admitted to the hospital because he was unable to safely ambulate. He was treated with subcutaneous unfractionated heparin to prevent deep venous thrombosis as part of routine care. Twenty-four hours after exposure to heparin, he developed an urticarial rash. The rash resolved promptly after discontinuing heparin and excluding other potential allergic triggers. Conclusions: In patients with alpha-gal syndrome, unfractionated heparin via a subcutaneous route at prophylactic dosing can precipitate immunoglobulin E–mediated systemic reactions and should be avoided.

Prophylactic Unfractionated Subcutaneous Heparin Does Not Increase Postoperative Hemorrhage in Elderly Patients Undergoing Emergency Neurosurgical Procedures.

PurposeThe purpose of this study is to evaluate the impact in the development of intracerebral hemorrhage in elderly critically ill patients who received prophylactic subcutaneous unfractionated heparin (SCUFH) less than 24 hours after undergoing emergency neurosurgery. MethodsA retrospective analysis was performed on patients who underwent emergency neurosurgery and were admitted to the surgical intensive care unit (SICU) at a tertiary care center over a 10-year period. Administration of prophylactic SCUFH within 24 hours of neurosurgery was required for inclusion. Demographic and clinical characteristics were recorded. The primary outcome was a rate of postoperative hemorrhagic complications with respect to age.ResultsWe identified 223 emergency neurosurgical patients: 100 (45%) patients did not receive prophylactic SCUFH and were excluded. The remaining 123 (55%) patients met all inclusion criteria, of whom 73 (59%) patients were under 65 years old, and 50 (41%) patients were over 65 years old. Patients under 65 years old had significantly lower body mass index (BMI), lower Acute Physiology and Chronic Health Evaluation (APACHE) II, APACHE III, and Simplified Acute Physiology Score (SAPS) scores, and shorter median SICU length of stay compared to patients over 65 years old. No statistically significant difference in the rate of postoperative hemorrhagic or non-hemorrhagic neurological complications was observed between patients in either age group. ConclusionAge over 65 years was not associated with a higher risk of postoperative hemorrhage in patients who received SCUFH after emergency neurosurgery. SCUFH can be safely used as a chemoprophylactic agent against venous thromboembolism for elderly patients when used within 24 hours after emergency neurosurgery.

Varying Dosages of Subcutaneous Unfractionated Heparin and Activated Partial Thromboplastin Time in Hospitalized Antepartum Patients: A Retrospective Cohort Analysis.

Venous thromboembolism (VTE) is a leading cause of maternal morbidity and mortality in the United States. Subcutanous unfractionated heparin (UFH) has been used for decades for VTE prophylaxis and under many obstetric quality of care initiatives, hospitalized antepartum patients now receive doses as high as 10,000 units every 12 hours. This practice increases the likelihood of UFH administration around the time that epidural labor analgesia is requested or neuraxial analgesia for cesarean delivery is needed. To clarify the effect of UFH on coagulation, we reviewed the care of hospitalized antepartum patients receiving VTE prophylaxis with UFH to determine the incidence of concurrent abnormal activated partial thromboplastin time (aPTT) values and associated risk factors. This retrospective cohort study used data from the University of Chicago Pharmacy database to identify hospitalized antepartum patients receiving subcutaneous UFH from June 1, 2016 to July 1, 2019. Our institutional protocol states that all patients hospitalized for antepartum conditions should receive pharmacologic prophylaxis empirically unless contraindicated. For patients receiving UFH, dosing was based on gestational age: 5000 units every 12 hours for first trimester antepartum patients, 7500 units every 12 hours for second trimester patients, and 10,000 units every 12 hours for patients in the third trimester. As per protocol, aPTT values were obtained 2 hours after the third dose of heparin, and platelet counts after 4 days. Data collection included demographics, comorbidities, heparin doses, aPTT values, platelet counts, creatinine if available, and anesthetic type and complications. Logistic regression was performed to determine the association between elevated aPTT >40 seconds and study variables. Of the 321 antepartum patients who received subcutaneous UFH, 33 (10.3%) had an aPTT >40 seconds, 4 of those 33 patients (12.1%) received 5000 units every 12 hours, 14 (42.2%) received 7500 units every 12 hours, and 15 (45.5%) received 10,000 units every 12 hours. The likelihood of a patient having aPTT >40 seconds was 2.8% with 5000 units every 12 hours, 18.9% with 7500 units every 12 hours, and 14.6% with 10,000 units every 12 hours. Elevated aPTT values are likely with total daily doses of 15,000 or 20,000 units subcutaneous UFH in hospitalized antepartum patients.

Tissue plasminogen activator for the treatment of adults with critical COVID-19: A pilot randomized clinical trial

Tissue plasminogen activator for the treatment of adults with critical COVID-19: A pilot randomized clinical trial

Equivalent VTE rates after total joint arthroplasty using thromboprophylaxis with aspirin versus potent anticoagulants: retrospective analysis of 4562 cases across a diverse healthcare system

BackgroundGuidelines support aspirin thromboprophylaxis for primary total hip and knee arthroplasty (THA and TKA) but supporting evidence has come from high volume centers and the practice remains controversial.MethodsWe studied 4562 Medicare patients who underwent elective primary THA (1736, 38.1%) or TKA (2826, 61.9%) at 9 diverse hospitals. Thirty-day claims data were combined with data from the health system’s electronic medical records to compare rates of venous thromboembolism (VTE) between patients who received prophylaxis with: (1) aspirin alone (47.3%), (2) a single, potent anticoagulant (29%), (3) antiplatelet agents other than aspirin or multiple anticoagulants (21.5%), or (4) low-dose subcutaneous unfractionated heparin or no anticoagulation (2.2%). Sub-analyses separately evaluating THA, TKA and cases from lower volume hospitals (n = 975) were performed.ResultsThe 30-day VTE incidence was 0.6% (29/4562). VTE rates were equal in patients receiving aspirin and those receiving a single potent anticoagulant (0.5% in both groups). Patients with VTE were significantly older than patients without VTE (mean 76.5 vs. 73.1 years, P = 0.04). VTE rate did not associate with sex or hospital case volume. On bivariate analysis considering age, aspirin did not associate with greater VTE risk compared to a single potent anticoagulant (OR = 2.1, CI = 0.7–6.3) with the numbers available. Odds of VTE were increased with use of subcutaneous heparin or no anticoagulant (OR = 6.4, CI = 1.2–35.6) and with multiple anticoagulants (OR = 3.6, CI = 1.1–11.2). THA and TKA demonstrated similar rates of VTE (0.5% vs. 0.7%, respectively, P = 0.43). Of 975 cases done at lower volume hospitals, 387 received aspirin, none of whom developed VTE.ConclusionsThis study provides further support for aspirin as an effective form of pharmacological VTE prophylaxis after total joint arthroplasty in the setting of a multi-modal regimen using 30-day outcomes. VTE occurred in 0.7% of primary joint arthroplasties. Aspirin prophylaxis did not associate with greater VTE risk compared to potent anticoagulants in the total population or at lower volume hospitals.

A Scoping Review of Alternative Anticoagulation Strategies for Hemodialysis Patients with a Mechanical Heart Valve

Introduction: Patients with end-stage renal disease (ESRD) have high rates of cardiac valvulopathy but can develop contraindications for vitamin K antagonist (VKA) therapy. We explored the evidence for alternative anticoagulation strategies in patients with ESRD with a contraindication for VKA therapy. Methods: A scoping review was completed, searching MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Web of Science, and Conference abstracts from inception to March 30, 2021. The study population was patients with ESRD who were on VKA therapy and developed a contraindication to VKA therapy use. All data regarding studies, patient characteristics, anticoagulation strategy, and clinical outcomes were summarized. Results: Twenty-three articles met inclusion criteria. These articles included 57 patients. Contraindications to VKA therapy included calcific uremic arteriolopathy (CUA) (n = 55) and warfarin-induced skin necrosis (n = 2). All studies were either case reports or case series. There were 10 anticoagulation strategies identified. Continuation of VKA therapy was associated with increased death and decreased rates of CUA resolution (80.0% and 10.0%, respectively), compared to apixaban (24.0% and 70.8%), subcutaneous (SC) low-molecular-weight heparin (LMWH) (14.3%, 85.7%), and SC unfractionated heparin (0.0%, 100.0%). While only 5 patient cases were reported with mechanical heart valves, SC LMWH use has been reported in this context with good outcomes. Conclusions: In patients with ESRD who develop a contraindication to VKA therapy, several alternative anticoagulation strategies have been reported with superior outcomes to VKA continuation. While outcomes appear superior to continuation of VKA therapy, more data are required before definitive recommendations can be made for the patient with ESRD and a mechanical heart valve.

Comparison of Chemical and Mechanical Prophylaxis of Venous Thromboembolism in Non-surgical Mechanically Ventilated Patients.

To compare the efficacy of mechanical and chemical prophylaxis in non-surgically mechanically ventilated patients in terms of reduction in mortality and length of hospital stay.A total of 200 patients admitted to intensive care units (ICUs) were recruited retrospectively. Half participants received mechanical prophylaxis and half received chemical prophylaxis. Patients with medical diseases with age 18 years or above, both genders, Pakistani nationals, receiving mechanical ventilation for more than 48 hours or receiving subcutaneous low molecular weight (LMW) heparin or subcutaneous unfractionated heparin were included. Cases who undergone surgery and were then admitted to ICU, those who received both mechanical and chemical therapies, and patients who received anticoagulant treatment before admission to ICU were excluded from the study. The patient’s age, gender, length of stay in ICU, and mortality were recorded in each group. Chi-square test was used to compare categorical data and Student t-test for continuous variables.The mean age was 55.51±8.37 years. The males were 108(54%) and females were 92(46%). The mortality rate was higher in the mechanical prophylaxis group (49%) than chemical (31%) statistically significantly (P=0.014). Similarly, the length of hospital stay was also higher in the mechanical prophylaxis group (7.27±0.897 days) than chemical (6.67±1.045) statistically (P<0.001).Chemical prophylaxis can reduce mortality and length of hospital stay more effectively than mechanical prophylaxis in ICUs admitted patients.

Effectiveness and Safety of Twice- Versus Thrice-Daily Subcutaneous Heparin for Venous Thromboembolism Prophylaxis at a Large Academic Medical Center.

Dosing variation of subcutaneous unfractionated heparin (UFH) exist for venous thromboembolism prophylaxis (VTEP). The purpose of this study was to compare the safety and effectiveness of thrice-daily (TID) versus twice-daily (BID) administration of UFH during a heparin shortage for VTEP. A single-center retrospective analysis was conducted in patients with orders for BID subcutaneous UFH during a heparin shortage from September 1, 2019, to February 4, 2020. These patients were matched to patients with TID subcutaneous UFH orders from January 1, 2019, to May 31, 2019. The primary outcome was the incidence of deep-vein thrombosis or pulmonary embolism confirmed by imaging during hospitalization. The secondary outcome was the incidence of major or clinically relevant nonmajor bleeding events as defined by International Society on Thrombosis and Haemostasis (ISTH) definitions. A total of 277 patients with orders for BID UFH and meeting inclusion criteria were evaluated and matched to patients who received TID UFH. After the exclusion criteria were implemented, 510 patients remained in the TID group. The primary outcome occurred in 4% of patients in the BID group and 3% in the TID group (P = 0.645). Major bleeding or clinically relevant nonmajor bleeding events occurred in 10% of patients in the BID group and 8% in the TID group (P = 0.310). There was no difference in effectiveness or safety of TID versus BID subcutaneous UFH for VTEP. During a heparin shortage, transitioning patients to BID UFH for VTEP to conserve supply may be considered.

Therapeutic efficacy of heparin and direct factor Xa inhibitors in cancer-associated cryptogenic ischemic stroke with venous thromboembolism

BackgroundAnticoagulation therapy, especially using heparin or recently developed oral direct factor Xa inhibitors (DiXals), is recommended as first-line treatment for cancer-related venous thromboembolism (VTE). However, the preventive efficacy of these anticoagulants for cancer-associated ischemic stroke is still unknown. We retrospectively investigated the efficacy of subcutaneous unfractionated heparin (UFH) and DiXals for preventing the recurrence of cancer-associated cryptogenic ischemic stroke with VTE. MethodsWe retrospectively studied consecutive patients with cancer-associated cryptogenic ischemic stroke and comorbid VTE who received subcutaneous UFH or oral DiXaIs at 9 hospitals. ResultFifty-three patients (24 treated with UFH and 29 treated with DiXaIs) were enrolled. Of these, 47 demonstrated systemic metastasis (cancer stage IV). During 30-day follow-up after initiation of anticoagulation therapy, recurrent ischemic stroke was observed in only 1 patient (4%) in the UFH group and in 9 patients (31%) in the DiXal group. The incidence of major bleeding complications was similar between the 2 groups (4% and 10%, respectively). The cumulative risk of ischemic stroke recurrence within 30 days was lower with UFH than with DiXals (competing risk analysis, p = 0.008). In the DiXal group, patients who experienced recurrence showed significantly higher D-dimer levels than those without recurrence. ConclusionIn patients with cancer-associated cryptogenic ischemic stroke and comorbid VTE, UFH demonstrated a lower rate of recurrent ischemic stroke than DiXaIs, and there were no differences in bleeding risk between the 2 treatments. D-dimer levels at stroke onset increased the risk of recurrence in the DiXal group but not in the UFH group.

The effect of subcutaneous unfractionated heparin and low-molecular weight heparin toward modification of diabetic acute influence on surgical wound healing in rats

Background and Objectives: Diabetes mellitus is one of the disturbing factors in surgical wound repair that recognizing these mechanisms, and modifying them can be useful in preventing surgical wound complications. The aim of this study is to assess the effect of unfractionated heparin (UH) and low-molecular weight heparin (LMWH) on diabetic wounds in the rats. Materials and Methods: This study as a clinical trial in the animal phase was done in two groups that each group consists of three subgroups containing eight rats in each. Initially, under anesthesia, the skin was incised surgically, and interventions with UH in the first subgroup of each group, LMWH in the second subgroup, and normal saline in the third subgroup were performed. In the first group on the 7th day and the second group on the 10th day, wound biopsy was taken and examined pathologically. Finally, data were analyzed using Kruskal–Wallis and one-way analysis of variance statically test. Results: The results of this study showed in every two groups, there was a statistically significant difference between the subgroups for fibroblast and vascularity status, but this difference was not significant for epithelialization and collagen level. In addition, wound length in both the groups had a significant difference between subgroups. Conclusion: In this study, there was a relative difference between the administration of UH and low-molecular weight and surgical wound healing in diabetic rats.

Weight-adjusted tinzaparin for venous thromboembolism prophylaxis in bariatric surgery patients weighing 160 kg or more

IntroductionBariatric surgery patients experience an increased risk of venous thromboembolism (VTE), however, the optimal dose of low-molecular-weight heparin for VTE prophylaxis remains uncertain. Currently, St. Joseph's Healthcare Hamilton utilizes a weight-adjusted tinzaparin dosage (50 to 75 units/kg rounded to nearest pre-filled syringe) for postoperative VTE prophylaxis. ObjectivesThis study analyzed the safety of weight-adjusted tinzaparin for VTE prophylaxis in bariatric surgery patients weighing ≥160 kg. MethodsThis was a retrospective study involving patients weighing ≥160 kg that underwent bariatric surgery from September 2015 to September 2019. Patients received a single dose of weight-adjusted subcutaneous unfractionated heparin (UFH) [5000 or 7500 IU] immediately prior to surgery, subcutaneous UFH [5000 IU, 7500 IU, or unspecified] immediately postoperatively, and either 10,000 or 14,000 IU of tinzaparin, beginning on the day after surgery, for 10 days. Intra-operative sequential compression devices could be used at the attending surgeon's discretion. Occurrence of VTE and major bleeding within 30 days of surgery were assessed. ResultsA total of 389 patients were included for analysis, all patients received in-hospital follow-up while 349 patients had also 30-day follow-up. For the primary safety and efficacy analysis of in-hospital events, VTE and major bleeding rates were 0.26% [95% CI 0.01%–1.44%] (1/389) and 0.77% [95% CI 0.21%–2.24%] (3/389) respectively. For patients with 30-day follow-up VTE and major bleeding rates were 0.57% [95% CI 0.1%–2.07%] (2/349) and 1.43% [95% CI 0.61%–3.3%] (5/349) respectively. ConclusionsWeight-adjusted tinzaparin was associated with a low risk of bleeding and VTE events, supporting its use for VTE prophylaxis for patients weighing ≥160 kg.