Symptomatic catheter-associated thrombosis in pediatric trauma patients: Choose your access wisely

Venous Thromboembolism Prophylaxis in High-Risk Pediatric Trauma Patients

Importance

The indications, safety, and efficacy of chemical venous thromboembolism prophylaxis (cVTE) in pediatric trauma patients remain unclear. A set of high-risk criteria to guide cVTE use was recently recommended; however, these criteria have not been evaluated prospectively.

Objective

To examine high-risk criteria and cVTE use in a prospective multi-institutional study of pediatric trauma patients.

Design, Setting, and Participants

This cohort study was completed between October 2019 and October 2022 in 8 free-standing pediatric hospitals designated as American College of Surgeons level I pediatric trauma centers. Participants were pediatric trauma patients younger than 18 years who met defined high-risk criteria on admission. It was hypothesized that cVTE would be safe and reduce the incidence of VTE.

Exposures

Receipt and timing of chemical VTE prophylaxis.

Main Outcomes and Measures

The primary outcome was overall VTE rate stratified by receipt and timing of cVTE. The secondary outcome was safety of cVTE as measured by bleeding or other complications from anticoagulation.

Results

Among 460 high-risk pediatric trauma patients, the median (IQR) age was 14.5 years (10.4-16.2 years); 313 patients (68%) were male and 147 female (32%). The median (IQR) Injury Severity Score (ISS) was 23 (16-30), and median (IQR) number of high-risk factors was 3 (2-4). A total of 251 (54.5%) patients received cVTE; 62 (13.5%) received cVTE within 24 hours of admission. Patients who received cVTE after 24 hours had more high-risk factors and higher ISS. The most common reason for delayed cVTE was central nervous system bleed (120 patients; 30.2%). There were 28 VTE events among 25 patients (5.4%). VTE occurred in 1 of 62 patients (1.6%) receiving cVTE within 24 hours, 13 of 189 patients (6.9%) receiving cVTE after 24 hours, and 11 of 209 (5.3%) who had no cVTE (P = .31). Increasing time between admission and cVTE initiation was significantly associated with VTE (odds ratio, 1.01; 95% CI, 1.00-1.01; P = .01). No bleeding complications were observed while patients received cVTE.

Conclusions and Relevance

In this prospective study, use of cVTE based on a set of high-risk criteria was safe and did not lead to bleeding complications. Delay to initiation of cVTE was significantly associated with development of VTE. Quality improvement in pediatric VTE prevention may center on timing of prophylaxis and barriers to implementation.

Risk factors and incidence of central venous access device-related thrombosis in hospitalized children: a systematic review and meta-analysis

BACKGROUND

The risk factors for central venous access device-related thrombosis (CRT) in children are not fully understood. We used evidence-based medicine to find the risk factors for CRT by pooling current studies reporting risk factors of CRT, aiming to guide clinical diagnosis and treatment.

METHODS

A systematic search of PubMed, Web of Science, Embase, Cochrane Library, Scopus, CNKI, Sinomed, and Wanfang databases was conducted. RevMan 5.4 was employed for data analysis.

RESULTS

The review included 47 studies evaluating 262,587 children with CVAD placement. Qualitative synthesis and quantitative meta-analysis identified D-dimer, location of insertion, type of catheter, number of lumens, catheter indwelling time, and central line-associated bloodstream infection as the most critical risk factors for CRT. Primarily due to observational design, the quality of evidence was regarded as low certainty for these risk factors according to the GRADE approach.

CONCLUSION

Because fewer high-quality studies are available, larger sample sizes and well-designed prospective studies are still needed to clarify the risk factors affecting CRT. In the future, developing pediatric-specific CRT risk assessment tools is important. Appropriate stratified preventive strategies for CRT according to risk assessment level will help improve clinical efficiency, avoid the occurrence of CRT, and alleviate unnecessary suffering of children.

IMPACT

This is the latest systematic review of risk factors and incidence of CRT in children. A total of 47 studies involving 262,587 patients were included in our meta-analysis, according to which the pooled prevalence of CRT was 9.1%. This study identified several of the most critical risk factors affecting CRT in children, including D-dimer, insertion location, type of catheter, number of lumens, catheter indwelling time, and central line-associated bloodstream infection (CLABSI).

Device Related Thrombosis and Bleeding in Pediatric Health Care: A Meta-analysis

CONTEXT

The risk of invasive device-related thrombosis and bleeding contributes to morbidity and mortality, yet their prevalence by device-types is poorly understood.

OBJECTIVES

This study aimed to estimate pooled proportions and rates of thrombotic and bleeding complications associated with invasive devices in pediatric health care.

DATA SOURCES

Medline, CINAHL, Embase, Web of Science, Scopus, Cochrane CENTRAL, clinical trial registries, and unpublished study databases were searched.

STUDY SELECTION

Cohort studies and trials published from January 2011 to June 2022, including (1) indwelling invasive devices, (2) pediatric participants admitted to a hospital, (3) reporting thrombotic and bleeding complications, and (4) published in English, were included.

DATA EXTRACTION

Meta-analysis of observational studies in epidemiology guidelines for abstracting and assessing data quality and validity were used.

MAIN OUTCOMES AND MEASURES

Device-specific pooled thromboses (symptomatic, asymptomatic, unspecified) and bleeding (major, minor).

RESULTS

Of the 107 studies, 71 (66%) focused on central venous access devices. Symptomatic venous thromboembolism in central venous access devices was 4% (95% confidence interval [CI], 3-5; incidence rate 0.03 per 1000 device-days, 95% CI, 0.00-0.07), whereas asymptomatic was 10% (95% CI, 7-13; incidence rate 0.25 per 1000 device-days, 95% CI, 0.14-0.36). Both ventricular assist devices (28%; 95% CI, 19-39) and extracorporeal membrane oxygenation (67%; 95% CI, 52-81) were often associated with major bleeding complications.

CONCLUSIONS

This comprehensive estimate of the incidence and prevalence of device-related thrombosis and bleeding complications in children can inform clinical decision-making, guide risk assessment, and surveillance.

Evaluation of venous thromboembolism risk factors reveals subtype heterogenicity in children with central venous catheters: a multicenter study from the Children's Hospital Acquired Thrombosis consortium

BACKGROUND

Acutely ill and medically complex children frequently rely on central venous catheters (CVCs) to provide life-sustaining treatment. Unfortunately, catheter-related thrombosis (CRT) is a serious and common complication. Little is known why some with a CVC develop CRT and others develop venous thromboembolism unrelated to the CVC (non-CRT).

OBJECTIVES

The aim of this study was to identify factors associated with CRT in children with hospital-acquired venous thromboembolism (HA-VTE).

METHODS

This case-case study included participants in the Children's Hospital Acquired Thrombosis Registry with HA-VTE and CVC aged 0 to 21 years from 8 US children's hospitals. Participants were excluded if they developed HA-VTE prior to CVC insertion or if the CVC insertion date was unknown. Logistic regression models were used to assess associations between clinical factors and CRT status.

RESULTS

There were 1144 participants with HA-VTE who had a CVC. CRT developed in 833 participants, and 311 developed non-CRT. Multivariable analysis showed increased odds of CRT (compared with non-CRT) in participants with peripherally inserted central catheters (odds ratio [OR], 3.80; 95% CI, 2.04-7.10; p < .001), CVCs inserted in the femoral vein (OR, 4.45; 95% CI, 1.70-11.65; p = .002), multiple CVCs (OR, 1.42; 95% CI, 1.18-1.71; p < .001), and CVC malfunction (OR, 3.30; 95% CI, 1.80-6.03; p < .001).

CONCLUSION

The findings of this study provide new insights on risk factor differences between CRT and non-CRT. Prevention efforts should be directed at modifying the type of CVC, insertion location, and/or number of CVCs placed, if possible, to decrease the incidence of CRT.

Venous thromboembolic screening in pediatric trauma: A prospective cohort study of risk-stratified ultrasonography

BACKGROUND

This prospective observational cohort study evaluates risk-stratified venous thromboembolism (VTE) screening in injured children. While the reported incidence of VTE is 6% to 10% among critically injured children, there is no standard for screening. Venous thromboembolism may have long-term sequelae in children, including postthrombotic syndrome.

METHODS

Patients admitted to a level 1 pediatric trauma center were risk stratified for VTE using a validated prediction algorithm. Children at high risk (risk scores ≥523; i.e., ≥1% risk) received screening duplex ultrasonography. Children at moderate risk (risk scores 410-522; i.e., 0.3-0.99% risk) were screened as a comparison/control.

RESULTS

Three-hundred fifty-five children were consecutively risk stratified from October 2019 to May 2021. Forty-seven children received screening duplex ultrasounds: 21 from a high-risk cohort and 26 from a moderate-risk cohort. Four children were diagnosed with VTE in the high-risk cohort compared with seven in the moderate-risk cohort ( p = 0.53). Total incidence of VTE among screened children was 23.4% (11 of 47). Asymptomatic VTE accounted for 81.8% of all events (9 of 11). Fifty-four percent (6 of 11) of VTE were central venous catheter associated. Venous thromboembolism in surviving children resolved by 3 to 6 months with no symptoms of postthrombotic syndrome after 1 year. No cases of VTE were identified in unscreened children, yielding an institutional VTE incidence of 3.1% (11 of 355).

DISCUSSION

Risk-stratified screening demonstrates a significant incidence of asymptomatic VTE in injured children. These results may guide reevaluation of prediction algorithms developed from symptomatic VTE risk and longitudinal study of the sequelae of asymptomatic VTE.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level III.

Risk factors for central venous catheter-related thrombosis in hospitalized children: a single-center a retrospective cohort study

BACKGROUND

This study aimed to explore the risk factors of catheter-related thrombosis (CRT) in children in Southwest China who underwent central venous catheter (CVC) insertion.

METHODS

An observational cohort study was conducted at a single tertiary center in southwest China between November 2019 and February 2020. All patients who received a CVC were enrolled and Doppler-ultrasound examination was performed weekly until CVC removal. All patients in this study were hospitalized and were observed and followed up in this hospital. Patient demographics, medication, biochemical indexes, catheter maintenance practice, activities after CVC placement data were analyzed. The Kaplan-Meier method was used to calculate the incidence of CRT, and the Cox regression model was used to analyze the factors influencing CRT.

RESULTS

A total of 594 children were included in the study, and the median indwelling time was 10 days, with the shortest being 1 day and the longest 60 days. The overall incidence of CRT was 26.60% (158/594), the 15-day cumulative incidence rate was 30.81%, and the 45-day cumulative incidence rate was 46.27%. After 45 days, the incidence of CRT further increased. Age <12 months [hazard ratio (HR), 1.654; 95% confidence interval (CI): 1.171-2.338], use of 20% mannitol or glycerol fructose (HR, 1.593; 95% CI: 1.058-2.398), CVC placement by a pediatric intensive care unit (PICU) doctor (HR, 1.921; 95% CI: 1.347-2.740), placement length ≥9 cm (HR, 1.633; 95% CI: 1.142-2.336), and D-dimer >1.5 mg/L (HR, 1.451; 95% CI: 1.044-2.015) were risk factors for CRT. Limb exercises (HR, 0.660; 95% CI: 0.469-0.929) after placement was a protective factor for CRT.

CONCLUSIONS

The incidence of CRT was higher in children with CVCs, and the key duration of CRT monitoring should be within 15 and 45 days after placement. Patients with age <12 months, using 20% mannitol or glycerol fructose, insertion length ≥9 cm, D-dimer >1.5 mg/L before placement are more likely to happen CVC-CRT than other patient, and it is necessary to be highly vigilant and take preventive measures.

Point-of-Care Ultrasound for Central Venous Assessment in the Emergency Department: A Prospective Study Comparing the Femoral and Internal Jugular Veins

OBJECTIVES

The objective of this study was to estimate the width, height, and depth of the femoral vein (FV) and internal jugular vein (IJV), both sites of potential central line placement in children, using point-of-care ultrasound.

METHODS

This was a prospective observational study. Point-of-care ultrasound was used to measure the width, height, and depth of the right FV and IJV in 100 children. The primary outcome was a comparison of the widths of the FV and the IJV in the same child. Our primary hypothesis was that the IJV would be wider than the FV. Secondary outcome measures included comparison of the heights and depths the FV and IJV and description of vessel overlap frequency between the 2 sites.

RESULTS

A total of 106 children were enrolled, with 6 subjects excluded, and equally divided into 5 age groups (0-30 days, 1-24 months, 2-5 years, 6-11 years, and 12-17 years). The FV/IJV width ratios (95% confidence interval) by age were 0.58 (0.49-0.68), 0.53 (0.43-0.66), 0.57 (0.49-0.67), 0.68 (0.55-0.85), and 0.73 (0.62-0.85), all P < 0.002. The FV/IJV height ratios were <1 in all age groups, with P < 0.003 in the 4 youngest age groups. The FV/IJV depth ratios were >1 in 6 to 11 years (P = 0.018) and 12 to 17 years (P < 0.001).

CONCLUSIONS

The IJV was significantly wider and taller than the FV in the same child in all age groups. The FV was significantly deeper than the IJV in children 6 years and older. This supports the use of the IJV as a potential site when placing ultrasound-guided central lines in children.

Iatrogenic vascular trauma and complications of vascular access in children

Vascular access is frequently a critical component of the diagnostic and therapeutic procedures required to manage childhood illnesses, including many emergent conditions and critical illnesses. Vascular access in the pediatric population presents unique challenges, and many clinical and technical factors must be considered to avoid complications that can occur with vascular access procedures. This article reviews various aspects of vascular access and associated iatrogenic trauma in children, including risk factors, management of complications, and preventive measures to avoid complications. It is only with a comprehensive understanding of the topic that vascular access in children can be performed safely, effectively, and efficiently.

Thromboembolic Complications of Vascular Catheters Used for Pediatric Continuous Renal Replacement Therapy: Prevalence in a Single-Center, Retrospective Cohort

OBJECTIVES

Pediatric venous thromboembolic events are commonly associated with in situ central venous catheters. The risk for severe venous thromboembolism increases if a larger portion of the vessel lumen is occupied by the central venous catheter. A functioning vascular catheter is required when the continuous renal replacement therapy is used in critically ill children. Due to the high blood flow required for continuous renal replacement therapy, the external diameter of the catheter needs to be larger than a conventional central venous catheter used for venous access, potentially increasing the risk of venous thromboembolism. However, children on continuous renal replacement therapy often receive systemic anticoagulation to prevent filter clotting, possibly also preventing venous thromboembolism. The frequency of catheter-related venous thromboembolic events in this setting has not been described. Our main objective was to determine the prevalence of catheter-related venous thromboembolism in pediatric continuous renal replacement therapy.

DESIGN

Retrospective cohort study.

SETTING

Tertiary multidisciplinary academic pediatric hospital.

PATIENTS

Patients 0-18 years old with a vascular catheter used for continuous renal replacement therapy.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

In our series of 80 patients, we used 105 vascular catheters. The median age of the patients was 10 months and PICU mortality rate was 21%. Venous thromboembolic events were considered to be catheter related if located in the same vein as the vascular catheter and radiologically verified. Six (5.7%) catheter-related venous thromboembolic events were found. The clinically relevant complications of venous thromboembolism included superior vena cava syndrome and catheter dysfunction. In one patient, severe and life-threatening pulmonary embolism occurred. In comparison with patients without venous thromboembolism, venous thromboembolic events were associated with lower body weight (p = 0.03) and longer durations of continuous renal replacement therapy (p < 0.01), mechanical ventilation (p = 0.03), and PICU stay (p < 0.01). Five out of six venous thromboembolisms appeared in neonates.

CONCLUSIONS

Catheter-related venous thromboembolism is a clinically relevant complication of pediatric continuous renal replacement therapy, with a prevalence of 5.7% in our cohort. Clinicians involved in pediatric continuous renal replacement therapy need to be vigilant for symptoms of venous thromboembolisms and initiate appropriate treatment as soon as possible.

Venous thromboembolism prophylaxis after pediatric trauma

In recent years, there has been an increased focus on developing and validating venous thromboprophylaxis guidelines in the pediatric trauma population. We review the current literature regarding the incidence of and risk factors for venous thromboembolism (VTE) and the use of prophylaxis in the pediatric trauma population. Risk factors such as age, injury severity, central venous catheters, mental status, injury type, surgery, and comorbidities can lead to a higher incidence of VTE. Risk stratification tools have been developed to determine whether mechanical and/or pharmacologic prophylaxis should be implemented depending on the degree of VTE risk. When VTE risk is high, pharmacologic prophylaxis, such as with low molecular weight heparin, is often initiated. However, the timing and duration of VTE prophylaxis is dependent on patient factors including ambulatory status and contraindications such as bleeding. In addition, the utility of screening ultrasound for VTE surveillance has been evaluated and though they are not widely recommended, no formal guidelines exist. While more research has been done in recent years to assess the most appropriate type, timing, and duration of VTE prophylaxis, further studies are warranted to create optimal guidelines for decreasing the risk of VTE after pediatric trauma.

A Real-time Risk-Prediction Model for Pediatric Venous Thromboembolic Events

BACKGROUND

Hospital-associated venous thromboembolism (HA-VTE) is an increasing cause of morbidity in pediatric populations, yet identification of high-risk patients remains challenging. General pediatric models have been derived from case-control studies, but few have been validated. We developed and validated a predictive model for pediatric HA-VTE using a large, retrospective cohort.

METHODS

The derivation cohort included 111 352 admissions to Monroe Carell Jr. Children's Hospital at Vanderbilt. Potential variables were identified a priori, and corresponding data were extracted. Logistic regression was used to estimate the association of potential risk factors with development of HA-VTE. Variable inclusion in the model was based on univariate analysis, availability in routine medical records, and clinician expertise. The model was validated by using a separate cohort with 44 138 admissions.

RESULTS

A total of 815 encounters were identified with HA-VTE in the derivation cohort. Variables strongly associated with HA-VTE include history of thrombosis (odds ratio [OR] 8.7; 95% confidence interval [CI] 6.6-11.3; P < .01), presence of a central line (OR 4.9; 95% CI 4.0-5.8; P < .01), and patients with cardiology conditions (OR 4.0; 95% CI 3.3-4.8; P < .01). Eleven variables were included, which yielded excellent discriminatory ability in both the derivation cohort (concordance statistic = 0.908) and the validation cohort (concordance statistic = 0.904).

CONCLUSIONS

We created and validated a risk-prediction model that identifies pediatric patients at risk for HA-VTE development. We anticipate early identification of high-risk patients will increase prophylactic interventions and decrease the incidence of pediatric HA-VTE.

Enoxaparin Reduces Catheter Associated Venous Thrombosis Following Infant Cardiac Surgery

BACKGROUND

Central venous catheter (CVC) related venous thrombosis (VT) following pediatric cardiac surgery increases the morbidity and mortality. Although VT prevention using low dose anticoagulation has proven ineffective, anticoagulation using high dose enoxaparin to achieve a therapeutic anti-xa level has not been studied. We hypothesized that high dose enoxaparin would reduce VT after pediatric cardiac surgery.

METHODS

Enoxaparin was administered to infants < 150 days when post-operative CVC duration was anticipated to extend beyond 5 days. The primary outcome was the rate of VT, re-exploration for bleeding, and post-operative red blood cell (RBC) transfusions per 1,000 CVC days.

RESULTS

From 2012-2019, 157 infants were treated with enoxaparin. Infants were divided into two groups: 1) SubTherapeutic (SubTher) (N = 51) - therapeutic anti-xa level (0.5-1.0 IU/mL) was not achieved, 2) Therapeutic (Ther) (N = 106) - therapeutic anti-xa level was achieved. Baseline demographics demonstrated a lower age at operation within the Ther group. The SubTher group had a higher VT rate/1,000 CVC days (8.2) compared to the Ther group (2.6; p=0.005). Re-exploration for bleeding was similar between groups. The number of post-operative RBC transfusions/1,000 CVC days was significantly greater in the SubTher group (109.4 vs. 81.6; p=0.008). Multivariate analysis demonstrated that higher median anti-xa levels reduced the risk of VT (OR 0.02, CI: 0.001, 0.63; p = 0.02).

CONCLUSIONS

This data suggests that enoxaparin treatment resulting in a therapeutic anti-xa level reduces post-operative CVC associated VT without increasing bleeding complications.

Focal Adhesion Kinase Inhibitor Inhibits the Oxidative Damage Induced by Central Venous Catheter via Abolishing Focal Adhesion Kinase-Protein Kinase B Pathway Activation

The vascular injury induced by central venous catheter (CVC) indwelling is the basis for the occurrence and development of CVC-related complications, such as phlebitis, venous thrombosis, and catheter-related infections. Focal adhesion kinase (FAK) and FAK-protein kinase B (AKT) signaling pathway are of great significance in tissue repair after trauma. Here, we investigated the role and mechanism of the FAK inhibitor (1,2,4,5-phenyltetramine tetrahydrochloride (Y15)) in oxidative damage caused by CVC. EA.hy926 cells were divided into the control group (normal control), CVCs+scratches group (the intercepted CVC segments coculturing with scratched EA.hy926 cells), and CVCs+scratches+Y15 group (Y15 was added to the cell culture supernatant with CVCs + scratches at a final concentration of 50 μmol·L⁻¹). New Zealand rabbits were randomly divided into the control group (normal control), CVC group (CVC was inserted through the rabbit's right jugular vein to the junction of the right atrium and superior vena cava), and CVC+Y15 group (CVC was immersed in a 50 μmol·L⁻¹ Y15 solutions before insertion). The levels of markers and proteins related to oxidative damage in cells, cell culture supernatant, serum, and external jugular vein were measured by commercial kits and western blot, respectively. We found that Y15 treatment significantly decreased ROS and MDA levels and increased cell viability, NO, and SOD levels in a time-dependent manner in rabbit serum and cell culture supernatant. In addition, Y15 effectively reduced the CVC-induced pathological changes of damaged vascular tissues. Y15 also downregulated the levels of p-FAK Tyr 397 and p-Akt Ser 473 in damaged external jugular vein and EA.hy926 cells. These findings suggest that Y15 alleviated CVC-induced oxidative damage to blood vessels by suppressing focal FAK-Akt pathway activation.

Hemostatic Balance in Severe Trauma

Acute coagulopathy is prevalent in adult and pediatric trauma patients and is associated with increased morbidity and mortality. While reasonable hypotheses have been created to explain the underlying perturbations of adult trauma coagulopathy (i.e., tissue factor-related increase in thrombin generation, protein C activation, hypoperfusion, and hyperfibrinolysis), only a small number of studies have been performed to prove whether these mechanisms can likewise be detected in pediatric trauma patients. In addition, severe hypofibrinogenemia (<100 mg/dL) is a frequent finding in pediatric trauma patients (>20%). Although the probability of life-threatening coagulopathy is low with minor to moderate injury, it is present in almost all patients with an injury severity score >25, hypotension, hypothermia, and acidosis. As these multifactorial changes in hemostasis cannot be adequately and rapidly measured using standard laboratory testing, the use of viscoelastic measurements has been established in adult trauma management, but prospective studies in children are urgently needed. Apart from diagnostic challenges, several studies have focused on the impact of blood product ratios on the treatment of massively bleeding pediatric trauma patients. The majority of these studies were unable to show improved survival by using higher plasma to red blood cell ratios or higher platelet to red blood cells ratios, but there are no published randomized trials to definitively answer this question. A goal-directed transfusion protocol using viscoelastic tests together with early substitution with an antifibrinolytic and fibrinogen replacement is a promising alternative to traditional ratio-based interventions. Another crucial factor in treating trauma-induced coagulopathy is the early detection of hypofibrinogenemia, a common condition in massively transfused patients. Early treatment of hypofibrinogenemia is associated with improved morbidity and mortality in adults, but needs to be further studied in future pediatric trials. Pediatric trauma patients are not only threatened by coagulopathy-related bleeding but are also at higher risk for venous thromboembolism. Pediatric trauma patients with brain injury, central venous catheters, immobilization, or surgical procedures are at highest risk for developing a deep venous thrombosis. There are no specific pediatric guidelines established to prevent venous thromboembolism in children suffering from traumatic injury.