Prophylactic anticoagulation to prevent venous thromboembolism in traumatic intracranial hemorrhage: a decision analysis

Thromboelastometry-Based Prophylaxis for Venous Thromboembolism in the Acute Period Following Isolated Severe Traumatic Brain Injury

Objective

Traumatic brain injury (TBI) is an independent risk factor for venous thromboembolism (VTE). This study aimed to determine the optimal timing for initiating pharmacological thromboprophylaxis for VTE in patients with isolated severe TBI using rotational thromboelastometry (ROTEM).

Methods

This single-center observational study enrolled 115 patients aged 18-59 years with isolated severe TBI within the first 48 hours after injury.

Results

Using ROTEM data, we identified hypercoagulation due to an increase in clot density (MCF EXTEM >72), which was attributed to fibrinogen (MCF FIBTEM >25). From day 4, hypercoagulation occurred in 14.8% of the patients. By day 7, these changes were observed in 85.2% of patients. According to brain computed tomography findings, patients who received early VTE chemoprophylaxis on days 3-4 after severe TBI did not experience progression of hemorrhagic foci.

Conclusion

Our results emphasize the clinical significance of thromboelastometry in patients with isolated severe traumatic TBI. Anticoagulant prophylaxis started on 3-4 days after severe TBI was relatively safe, and most patients did not experience hemorrhagic foci progression. The data acquired in this study may enable the optimization of VTE chemoprophylactic approaches, thereby reducing the associated risks to patients.

Prognostic Significance of Plasma Insulin Level for Deep Venous Thrombosis in Patients with Severe Traumatic Brain Injury in Critical Care

BACKGROUND

Whether insulin resistance underlies deep venous thrombosis (DVT) development in patients with severe traumatic brain injury (TBI) is unclear. In this study, the association between plasma insulin levels and DVT was analyzed in patients with severe TBI.

METHODS

A prospective observational study of 73 patients measured insulin, glucose, glucagon-like peptide 1 (GLP-1), inflammatory factors, and hematological profiles within four preset times during the first 14 days after TBI. Ultrasonic surveillance of DVT was tracked. Two-way analysis of variance was used to determine the factors that discriminated between patients with and without DVT or with and without insulin therapy. Partial correlations of insulin level with all the variables were conducted separately in patients with DVT or patients without DVT. Factors associated with DVT were analyzed by multivariable logistic regression. Neurological outcomes 6 months after TBI were assessed.

RESULTS

Among patients with a mean (± standard deviation) age of 53 (± 16 years), DVT developed in 20 patients (27%) on median 10.4 days (range 4-22), with higher Acute Physiology and Chronic Health Evaluation II scores but similar Sequential Organ Failure Assessment scores and TBI severity. Patients with DVT were more likely to receive insulin therapy than patients without DVT (60% vs. 28%; P = 0.012); hence, they had higher 14-day insulin levels. However, insulin levels were comparable between patients with DVT and patients without DVT in the subgroups of patients with insulin therapy (n = 27) and patients without insulin therapy (n = 46). The platelet profile significantly discriminated between patients with and without DVT. Surprisingly, none of the coagulation profiles, blood cell counts, or inflammatory mediators differed between the two groups. Patients with insulin therapy had significantly higher insulin (P = 0.006), glucose (P < 0.001), and GLP-1 (P = 0.01) levels and were more likely to develop DVT (60% vs. 15%; P < 0.001) along with concomitant platelet depletion. Insulin levels correlated with glucose, GLP-1 levels, and platelet count exclusively in patients without DVT. Conversely, in patients with DVT, insulin correlated negatively with GLP-1 levels (P = 0.016). Age (P = 0.01) and elevated insulin levels at days 4-7 (P = 0.04) were independently associated with DVT. Patients with insulin therapy also showed worse Glasgow Outcome Scale scores (P = 0.001).

CONCLUSIONS

Elevated insulin levels in the first 14 days after TBI may indicate insulin resistance, which is associated with platelet hyperactivity, and thus increasing the risk of DVT.

Post-traumatic pulmonary embolism: incidence, physiopathology, risk factors of early occurrence, and impact outcome. A narrative review

BACKGROUND

Venous thromboembolism (VTE) is a well-established complication of trauma. So far, the factors that are related to early post-traumatic pulmonary embolism (PE) occurrence have been given little attention.

AIMS

We have conducted this literature review in order to analyze the incidence and the physiopathology of post-traumatic PE among intensive care unit (ICU) trauma patients, analyze the incidence of early post-traumatic PE, and elucidate risk factors associated with post-traumatic PE. Moreover, we aim to study the impact/outcome of post-traumatic PE in the ICU.

METHODS

We used the PubMed and EMBASE databases and entered the following key words in MeSH research: Deep vein thrombosis (DVT), Post-traumatic Pulmonary embolism, Early pulmonary-embolism, risk factors, and Prognosis.

RESULTS

The incidence of PE among trauma patients varies considerably, ranging from 0.35% to 24%. The incidence of early post-traumatic PE varies widely from 10 to 42%. After a traumatic injury, many factors have been found to be responsible for the formation of DVT and PE. In addition to the risk factors of hypercoagulability described by Virchow in his original triad, inflammation acting via endothelial damage may be considered as a fourth factor. The literature review showed that lower limb fractures and age are the most frequent factors associated with PE (particularly in early PE). The heterogeneity among studies limits reliable conclusions regarding the true risk factors for the timing of the occurrence of post-traumatic PE. Fatality from pulmonary embolism (PE) is close to 50% in some series. Moreover, high mortality rates, a high rate of nosocomial infections, and a prolonged stay in an ICU and/or in a hospital were found to be associated with the development of PE.

CONCLUSION

Post-traumatic PE is frequent in ICUs. Inflammation acting via endothelial damage may be considered as a fourth factor in addition to the Virchow's triad of risk factors for venous thrombosis. Fractures of the lower extremities, obesity, and age happen to be the most frequent factors associated with PE (in particular early PE). PE development was associated with high rates of mortality, nosocomial infections, and a prolonged stay in an ICU and/or in a hospital. Therefore, prevention is warranted.

Anticoagulant prophylaxis against venous thromboembolism following severe traumatic brain injury: A prospective observational study and systematic review of the literature

OBJECTIVES

Venous thromboembolism (VTE) is a serious complication following severe traumatic brain injury (TBI), however, anticoagulant prophylaxis remains controversial due to concerns of intracranial hemorrhage (ICH) progression. We examined anticoagulant prophylaxis practice patterns at a major trauma centre and determined risk estimates for VTE and ICH progression classified by timing of anticoagulant initiation.

PATIENTS AND METHODS

A 1-year prospective analysis of consecutive patients with severe TBI admitted to a Level-I trauma centre was conducted. In addition, we systematically reviewed the literature to identify studies on VTE and anticoagulant prophylaxis after severe TBI.

RESULTS

64 severe TBI patients were included. 83% of patients received anticoagulant prophylaxis, initiated ≥3d post-TBI in 67%. The in-hospital VTE incidence was 16% and there was no significant difference between patients who received early (<3d) versus late (≥3d) prophylaxis (10% vs. 16%). Rates of ICH progression (0% vs. 7%) were similar between groups. Our systematic review identified 5 studies with VTE rates ranging from 5 to 10% with prophylaxis, to 11-30% without prophylaxis. The effect of timing of anticoagulant prophylaxis initiation on ICH progression was not reported in any study.

CONCLUSION

VTE is a common complication after severe TBI. Anticoagulant prophylaxis is often started late (≥3d) post-injury. Randomized trials are justifiable and necessary to provide practice guidance with regards to optimal timing of anticoagulant prophylaxis.

Detailed assessment of benefits and risks of retrievable inferior vena cava filters on patients with complicated injuries: the da Vinci multicentre randomised controlled trial study protocol

INTRODUCTION

Retrievable inferior vena cava (IVC) filters have been increasingly used in patients with major trauma who have contraindications to anticoagulant prophylaxis as a primary prophylactic measure against venous thromboembolism (VTE). The benefits, risks and cost-effectiveness of such strategy are uncertain.

METHODS AND ANALYSIS

Patients with major trauma, defined by an estimated Injury Severity Score >15, who have contraindications to anticoagulant VTE prophylaxis within 72 hours of hospitalisation to the study centre will be eligible for this randomised multicentre controlled trial. After obtaining consent from patients, or the persons responsible for the patients, study patients are randomly allocated to either control or IVC filter, within 72 hours of trauma admission, in a 1:1 ratio by permuted blocks stratified by study centre. The primary outcomes are (1) the composite endpoint of (A) pulmonary embolism (PE) as demonstrated by CT pulmonary angiography, high probability ventilation/perfusion scan, transoesophageal echocardiography (by showing clots within pulmonary arterial trunk), pulmonary angiography or postmortem examination during the same hospitalisation or 90-day after trauma whichever is earlier and (B) hospital mortality; and (2) the total cost of treatment including the costs of an IVC filter, total number of CT and ultrasound scans required, length of intensive care unit and hospital stay, procedures and drugs required to treat PE or complications related to the IVC filters. The study started in June 2015 and the final enrolment target is 240 patients. No interim analysis is planned; incidence of fatal PE is used as safety stopping rule for the trial.

ETHICS AND DISSEMINATION

Ethics approval was obtained in all four participating centres in Australia. Results of the main trial and each of the secondary endpoints will be submitted for publication in a peer-reviewed journal.

TRIAL REGISTRATION NUMBER

ACTRN12614000963628; Pre-results.

D-dimer Is a Predictor of 28-Day Mortality in Critically Ill Patients Receiving Continuous Renal Replacement Therapy

BACKGROUND AND AIMS

Continuous renal replacement therapy (CRRT) is an important treatment in the intensive care unit (ICU). Nevertheless, the outcome of CRRT remains unclear. It is important to find a useful and easy indicator to predict the prognosis in patients on CRRT treatment. We undertook this study to observe the association between serum D-dimer level and mortality of ICU patients in the treatment of CRRT.

METHODS

A total of 149 patients who received CRRT were enrolled in our study. We observed the correlation of D-dimer with the information of biochemical parameters, acute physiology and chronic health evaluation II (APACHE II) score. We analyzed the association between serum D-dimer level before CRRT and 28-d mortality retrospectively. Furthermore, we used Cox regression analysis to assess whether D-dimer could be the independent risk factor for mortality.

RESULTS

There were significant correlations between D-dimer and C-reaction protein (r² = 0.033, p = 0.026), creatinine (r² = 0.066, p = 0.002) and APACHE II (r² = 0.036, p = 0.021). The difference in 28-d mortality risk between elevated D-dimer group and normal D-dimer group was significant (HR 2.872, 95% CI 1.563-5.278, p = 0.001), and the elevated D-dimer level was an independent risk factor for 28-d mortality (HR 2.067, 95% CI 1.104-3.872, p = 0.023). The difference in 28-d mortality was significant between groups (p <0.001). ROC curves showed that the area under the curve (AUC) of D-dimer was 0.763.

CONCLUSION

The present study demonstrates that serum D-dimer could be a useful and easy prognostic variable of 28-d mortality in critically ill patients who received CRRT.

Timing of Pharmacologic Venous Thromboembolism Prophylaxis in Severe Traumatic Brain Injury: A Propensity-Matched Cohort Study

BACKGROUND

Patients with severe traumatic brain injury (sTBI) are at high risk for developing venous thromboembolism (VTE). Nonetheless, pharmacologic VTE prophylaxis is often delayed out of concern for precipitating extension of intracranial hemorrhage (ICH). The purpose of this study was to compare the effectiveness of early vs late VTE prophylaxis in patients with sTBI, and to characterize the risk of subsequent ICH-related complication.

STUDY DESIGN

Adults with isolated sTBI (head Abbreviated Injury Scale score ≥3 and total Glasgow Coma Scale score ≤8) who received VTE prophylaxis with low-molecular-weight or unfractionated heparin were derived from the American College of Surgeons Trauma Quality Improvement Program (2012 to 2014). Patients were divided into EP (<72 hours) or LP (≥72 hours) groups. Propensity score matching was used to minimize selection bias. The primary end point was VTE (pulmonary embolism or deep vein thrombosis). Secondary outcomes were defined as late neurosurgical intervention (≥72 hours) or death.

RESULTS

We identified 3,634 patients with sTBI. Early prophylaxis was given in 43% of patients. Higher head injury severity, presence of ICH, and early neurosurgery were associated with late prophylaxis. Propensity score matching yielded a well-balanced cohort of 2,468 patients. Early prophylaxis was associated with lower rates of both pulmonary embolism (odds ratio = 0.48; 95% CI, 0.25-0.91) and deep vein thrombosis (odds ratio = 0.51; 95% CI, 0.36-0.72), but no increase in risk of late neurosurgical intervention or death.

CONCLUSIONS

In this observational study of patients with sTBI, early initiation of VTE prophylaxis was associated with decreased risk of pulmonary embolism and deep vein thrombosis, but no increase in risk of late neurosurgical intervention or death. Early prophylaxis may be safe and should be the goal for each patient in the context of appropriate risk stratification.

Clinical factors associated with venous thromboembolism risk in patients undergoing craniotomy

OBJECT

Patients undergoing craniotomy are at risk for developing venous thromboembolism (VTE). The safety of anticoagulation in these patients is not clear. The authors sought to identify risk factors predictive of VTE in patients undergoing craniotomy.

METHODS

The authors reviewed a national surgical quality database, the American College of Surgeons National Surgical Quality Improvement Program. Craniotomy patients were identified by current procedural terminology code. Clinical factors were analyzed to identify associations with VTE.

RESULTS

Four thousand eight hundred forty-four adult patients who underwent craniotomy were identified. The rate of VTE in the cohort was 3.5%, including pulmonary embolism in 1.4% and deep venous thrombosis in 2.6%. A number of factors were found to be statistically significant in multivariate binary logistic regression analysis, including craniotomy for tumor, transfer from acute care hospital, age ≥ 60 years, dependent functional status, tumor involving the CNS, sepsis, emergency surgery, surgery time ≥ 4 hours, postoperative urinary tract infection, postoperative pneumonia, on ventilator ≥ 48 hours postoperatively, and return to the operating room. Patients were assigned a score based on how many of these factors they had (minimum score 0, maximum score 12). Increasing score was predictive of increased VTE incidence, as well as risk of mortality, and time from surgery to discharge.

CONCLUSIONS

Patients undergoing craniotomy are at low risk of developing VTE, but this risk is increased by preoperative medical comorbidities and postoperative complications. The presence of more of these clinical factors is associated with progressively increased VTE risk; patients possessing a VTE Risk Score of ≥ 5 had a greater than 20-fold increased risk of VTE compared with patients with a VTE score of 0.

Timing for deep vein thrombosis chemoprophylaxis in traumatic brain injury: an evidence-based review

Multiple studies have addressed deep vein thrombosis chemoprophylaxis timing in traumatic brain injuries. However, a precise time for safe and effective chemoprophylaxis is uncertain according to experts. A comprehensive literature review on brain injuries was performed to delineate temporal proportions for 1) spontaneous intracranial hemorrhage (ICH) progression, 2) post-chemoprophylaxis ICH expansion, and 3) post-chemoprophylaxis deep vein thrombosis. Twenty-three publications were found including more than 5,000 patients. Spontaneous ICH expansion at 24 hours was 14.8% in 1,437 patients from chemoprophylaxis studies and 29.9% in 1,257 patients not in chemoprophylaxis studies (P < 0.0001). With low-risk ICH (n = 136), 99% of spontaneous ICH expansion occurred within 48 hours. In moderate or high-risk ICH (n = 109), 18% of spontaneous ICH expansion occurred after day 3. If patients with pre-chemoprophylaxis ICH expansion are included, the post-chemoprophylaxis ICH expansion proportion was 5.6% in 1,258 patients with chemoprophylaxis on days 1 to 3 and was 1.5% in 401 with chemoprophylaxis after day 3 (P = 0.0116). If patients with pre-chemoprophylaxis ICH expansion were excluded, the post-chemoprophylaxis ICH expansion proportion was 3.1% in 1,570 patients with chemoprophylaxis on days 1 to 3 and was 2.8% in 582 with chemoprophylaxis after day 3 (P = 0.7769). In diffuse axonal injury (n = 188), the post-chemoprophylaxis ICH expansion proportion was 1.6% with chemoprophylaxis after day 3. The deep vein thrombosis proportions were as follows: chemoprophylaxis on days 1 to 3, 2.6% in 2,384 patients; chemoprophylaxis on days 4 or 5, 2.2% in 831; and chemoprophylaxis on day 8, 14.1% in 99 (P < 0.0001). Spontaneous ICH expansion proportions at 24 hours substantially vary between chemoprophylaxis and non-chemoprophylaxis studies. Chemoprophylaxis should not be given within 3 days of injury for moderate-risk or high-risk ICH. Chemoprophylaxis is reasonable when low-risk patients have not developed ICH expansion within 48 hours post-injury. Chemoprophylaxis is also acceptable after day 3, when low-risk patients develop ICH expansion within 48 hours post-injury. In diffuse axonal injury patients who have not developed ICH within 72 hours, chemoprophylaxis is reasonable. Deep vein thrombosis proportions significantly increase when chemoprophylaxis is withheld for greater than 7 days.

Prevention of venous thrombotic events in brain injury: review of current practices

Venous thromboembolic event after traumatic brain injury represents a unique clinical challenge. Physicians must balance appropriate timing of chemoprophylaxis with risk of increased cerebral hemorrhage. Despite an increase in the literature since the 1990s, there are clear disparities in treatment strategies. This review discusses the prominent studies and subsequent findings regarding the topic with an attempt to establish recommendations using the existing evidence-based literature.

Preferences in traumatic intracranial hemorrhage: bleeding vs. clotting

Patients with traumatic brain injury and resultant intracranial hemorrhage (ICH) are at high risk for developing venous thromboembolism (VTE). The use of thromboprophylaxis is effective at decreasing the rate of VTE, but at the potential expense of an increased risk of ICH progression. Physicians must carefully consider both the benefits and risks of VTE prophylaxis before prescribing chemical anticoagulants to these patients. To help clarify this difficult choice, Scales and colleagues performed a decision analysis to determine whether the benefits of thromboprophylaxis outweigh the potential risk of worsening ICH. There is increasing evidence that bleeding risks are not as prominent as previously thought. Although the results were largely inconclusive, the present study has identified areas for future research.