Thromboprophylaxis in critical care

Evaluating the impact of continuous venovenous hemodiafiltration on the efficacy of prophylactic fondaparinux doses: a prospective single-center observational study

Critically ill patients often need continuous renal replacement therapy (CRRT). This process can remove particles as large as 10 kDa, including medications such as fondaparinux. In this study, we investigated whether patients who received prophylactic doses of fondaparinux and are treated with continuous veno-venous hemodiafiltration (CVVHDF) would achieve prophylactic levels of anti-Xa factor activity. In this observational study, we compared two groups of patients: 20 individuals who underwent CVVHDF and 20 individuals who did not undergo CVVHDF. Each patient received a prophylactic subcutaneous dose of 2.5 mg daily of fondaparinux. Anti-Xa factor activity was measured on the third day of treatment with fondaparinux. Blood samples were collected at four time points: immediately before the administration of fondaparinux and then 3, 6, and 9 h later. Anti-Xa factor activity levels were below the recommended range in the control group and in most CVVHDF patients but significantly increased after fondaparinux administration. Interestingly, individuals who underwent CVVHDF had greater anti-Xa factor activity than control patients did at several time points. In critically ill patients treated with prophylactic fondaparinux, CVVHDF appears to have a statistically significant but small effect on Xa factor activity. However, the clinical significance of this finding is unknown.Clinical Trial Registration: The study was prospectively registered at ClinialTrials.gov (NCT04671160).

Risk factors and a nomogram model for deep vein thrombosis in critically ill patients with sepsis: a retrospective analysis

Sepsis is one of the risk factors for deep vein thrombosis (DVT). However, studies on risk factors for DVT in critically ill patients with sepsis are limited, and no specific assessment tool is available for evaluating the risk of DVT in this population. We aimed to determine the risk factors of DVT and develop a simple nomogram for this vulnerable population. In this retrospective observational study, patients with sepsis using Sepsis-3 criteria, who were admitted to the intensive care unit (ICU) of West China Hospital of Sichuan University from January 2015 to May 2022, were enrolled. Patients with a diagnosis of DVT before admitting to ICU, cancer, trauma, pregnancy, surgery more than 45 min, or long-term use of glucocorticoids were excluded. Patients were assigned to the DVT group or non-DVT group based on the results of ultrasonography. We generated receiver operating characteristic curves (ROC) to calculate the cut-off of the continuous variables. A forest plot and a nomogram were developed by multivariable logistic regression. A total of 1057 patients were finally included. The multivariable logistic regression analysis showed that age (≥ 48 years old, odds ratio (OR) = 2.99, 95% confidence interval (CI): 2.19-4.12, P < 0.001), the use of vasoactive drugs (≥ 336 h, OR = 5.66, 95%CI 4.05-7.99, P < 0.001), PaO2/FiO2 (≤ 275, OR = 1.68, 95%CI 1.24-2.27, P < 0.001), respiratory infection (OR = 1.44, 95%CI 1.02-2.06, P < 0.05), D-dimer level (≥ 3.6, OR = 1.59, 95%CI 1.12-2.26, P < 0.05), fibrinogen level (≤ 3.9, OR = 1.45, 95%CI 1.09-1.95, P < 0.05), physical prophylaxis (OR = 0.51, 95%CI 0.37-0.71, P < 0.001) were independently associated with DVT. There were no significant differences in the insertion of the central venous catheter (CVC) or peripherally inserted central catheter (PICC), Sequential Organ Failure Assessment (SOFA) score, duration of mechanical ventilation, stay in ICU, and length of hospitalization between the two groups, while the DVT group had a higher proportion of use of pharmacologic thromboprophylaxis (61.8% vs. 47.2%, P < 0.001). In critically ill patients with sepsis, physical prophylaxis was found as an independent protective factor for DVT. Advanced age, long-term use of vasoactive drugs, elevated D-dimer levels, decreased fibrinogen levels, low oxygenation index, and respiratory infection were independent risk factors for DVT.

Effectiveness of different anticoagulation regimens in critically ill patients - experience from COVID 19 patients

This study compared the efficacy of therapeutic anticoagulation guided by anti-Xa levels vs. a D-dimer-based protocol in ICU patients with COVID-19. Given the heightened risk of thrombosis despite anticoagulation therapy in some cases, we hypothesised that anti-Xa measurement improves anticoagulation effectiveness and clinical outcomes in this population. We retrospectively analysed data from ICU patients at COVID Hospital Karaburma between April 2020 and December 2021. The primary outcome was the incidence of failed noninvasive ventilation necessitating intubation. Secondary endpoints included mortality rates, thromboembolic and bleeding complications, and anticoagulation effectiveness assessed by antifactor Xa activity. The analysis included 395 patients - 137 in the anti-Xa group and 258 in the D-dimer group. The D-dimer group showed a higher rate of failed noninvasive ventilation requiring intubation (65.7% vs. 50%, P  = 0.009). The overall mortality was 48.3%, significantly higher in the D-dimer group (52.7%) compared to the anti-Xa group (40.1%, P  = 0.02). Thromboembolic complications were lower in the anti-Xa group (2.9%) than in the D-dimer group (9.7%, P  = 0.014), with no significant difference in bleeding. Following the first LMWH administration, 70.8% of patients had anti-Xa levels below the therapeutic and 11.7% below the prophylactic range. Anti-Xa-guided anticoagulation improves survival and reduces thromboembolic complications compared to D-dimer-based treatment without increasing bleeding risk. This study highlights the potential of the anti-Xa assay in managing anticoagulation in critically ill COVID-19 patients. Our findings provide a foundation for future research on using anti-Xa measurements as a guiding tool to optimise anticoagulation therapy in other critically ill populations.

Pulmonary Embolism in Critically Ill Patients-Prevention, Diagnosis, and Management

Critically ill patients in the intensive care unit (ICU) are often immobilized and on mechanical ventilation, placing them at increased risk for thromboembolic diseases, particularly deep vein thrombosis (DVT) and, to a lesser extent, pulmonary embolism (PE). While these conditions are frequently encountered in the emergency department, managing them in the ICU presents unique challenges. Although existing guidelines are comprehensive and effective, they are primarily designed for patients presenting with PE in the emergency department and do not fully address the complexities of managing critically ill patients in the ICU. This review aims to summarize the available data on these challenging cases, offering a practical approach to the prevention, diagnosis, and treatment of PE, particularly when it is acquired in the ICU.

Contemporary management of major haemorrhage in critical care

Haemorrhagic shock is frequent in critical care settings and responsible for a high mortality rate due to multiple organ dysfunction and coagulopathy. The management of critically ill patients with bleeding and shock is complex, and treatment of these patients must be rapid and definitive. The administration of large volumes of blood components leads to major physiological alterations which must be mitigated during and after bleeding. Early recognition of bleeding and coagulopathy, understanding the underlying pathophysiology related to specific disease states, and the development of individualised management protocols are important for optimal outcomes. This review describes the contemporary understanding of the pathophysiology of various types of coagulopathic bleeding; the diagnosis and management of critically ill bleeding patients, including major haemorrhage protocols and post-transfusion management; and finally highlights recent areas of opportunity to better understand optimal management strategies for managing bleeding in the intensive care unit (ICU).

Venous thromboembolism in critically ill adult patients with hematologic malignancy: a population-based cohort study

PURPOSE

The aim of this study was to describe the incidence of venous thromboembolism (VTE) and major bleeding among hospitalized patients with hematologic malignancy, assessing its association with critical illness and other baseline characteristics.

METHODS

We conducted a population-based cohort study of hospitalized adults with a new diagnosis of hematologic malignancy in Ontario, Canada, between 2006 and 2017. The primary outcome was VTE (pulmonary embolism or deep venous thrombosis). Secondary outcomes were major bleeding and in-hospital mortality. We compared the incidence of VTE between intensive care unit (ICU) and non-ICU patients and described the association of other baseline characteristics and VTE.

RESULTS

Among 76,803 eligible patients (mean age 67 years [standard deviation, SD, 15]), 20,524 had at least one ICU admission. The incidence of VTE was 3.7% in ICU patients compared to 1.2% in non-ICU patients (odds ratio [OR] 3.08; 95% confidence interval [CI] 2.77-3.42). The incidence of major bleeding was 7.6% and 2.4% (OR 3.33; 95% CI 3.09-3.58), respectively. The association of critical illness and VTE remained significant after adjusting for potential confounders (OR 2.92; 95% CI 2.62-3.25). We observed a higher incidence of VTE among specific subtypes of hematologic malignancy and patients with prior VTE (OR 6.64; 95% CI 5.42-8.14). Admission more than 1 year after diagnosis of hematologic malignancy (OR 0.64; 95% CI 0.56-0.74) and platelet count ≤ 50 × 109/L at the time of hospitalization (OR 0.63; 95% CI 0.48-0.84) were associated with a lower incidence of VTE.

CONCLUSION

Among patients with hematologic malignancy, critical illness and certain baseline characteristics were associated with a higher incidence of VTE.

Case Report: PROS1 (p.Leu584Arg) pathogenic mutation causes portal and superior mesenteric venous thromboembolism

Background

Genetic and acquired risk factors are fundamental to developing venous thromboembolism. Autosomal dominant protein S deficiency caused by pathogenic mutations in the PROS1 gene is a well-known risk factor for thrombophilia.

Case presentation

We report a 30-year-old male patient who presented to the hospital with portal vein thrombosis. The patient had a history of abdominal pain for one month. Abdominal vascular CT showed venous thrombosis in the portal vein and superior mesenteric vein. He was diagnosed with "portal and superior mesenteric vein thrombosis, small bowel obstruction and necrosis, acute upper gastrointestinal bleeding (UGIB), hemorrhagic shock." Serum protein S levels were decreased, and gene sequencing revealed a heterozygous missense mutation in PROS1, c.1571T > G (p.Leu584Arg). The patient received anticoagulation therapy with Enoxaparin Sodium and rivaroxaban, transjugular intrahepatic portosystemic shunt (TIPS), and ICU treatments. Although the patient had a severe bleeding event during anticoagulation therapy, he recovered well after active treatment and dynamic monitoring of anti-Xa.

Conclusion

Hereditary protein S deficiency caused by a mutation in the PROS1 gene is the genetic basis of this patient, and Enoxaparin Sodium and rivaroxaban have been shown to be highly effective.

How to manage coagulopathies in critically ill patients

Coagulopathy is a severe and frequent complication in critically ill patients, for which the pathogenesis and presentation may be variable depending on the underlying disease. Based on the dominant clinical phenotype, the current review differentiates between hemorrhagic coagulopathies, characterized by a hypocoagulable and hyperfibrinolysis state, and thrombotic coagulopathies with a systemic prothrombotic and antifibrinolytic phenotype. We discuss the differences in pathogenesis and treatment of the common coagulopathies.

Prevalence of Venous Thromboembolism in Intensive Care Units: A Meta-Analysis

OBJECTIVE

Venous thromboembolism (VTE) is a life threating complication in intensive care units (ICUs). This study aimed to pool the prevalence of VTE and examined the risk factors of VTE in intensive care patients worldwide.

METHODS

A systematic search in PubMed, EMBASE and Web of Science databases was performed. Studies reported that the data on the prevalence of VTE or relevant information were synthesized using a random-effects model.

RESULTS

A total of 42 studies reporting on 27,344 patients were included. The pooled prevalence of VTE was 10.0% (95% CI: 7.0-14.0%). Subgroup and metaregression analyses found that thromboprophylaxis strategy, simplified acute physiology score (SAPS II), age, study quality, sample size, malignancy, sex, spinal cord injury and injury severity score (ISS) moderated the prevalence of VTE in intensive care patients.

CONCLUSIONS

The present meta-analysis revealed a high prevalence of VTE in critically ill patients. The risk factors of VTE included thromboprophylaxis strategy, SAPS II, age, malignancy, sex, spinal cord injury and ISS. Therefore, we need to pay more attention to high-risk populations of VTE in intensive care patients.