Venous thromboembolism risk factors in a pediatric trauma population

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.

Thromboprophylaxis in pediatric patients with earthquake-related crush syndrome: a single centre experience

PURPOSE

Injuries increase the risk of venous thromboembolism (VTE). However, the literature on the management of anticoagulant therapy in pediatric patients with crush injury is limited. In this study, we aimed to share our experience about anticoagulant thromboprophylaxis in pediatric patients with earthquake-related crush syndrome.

METHODS

This study included patients who were evaluated for VTE risk after the Turkey-Syria earthquake in 2023. Since there is no specific pediatric guideline for the prevention of VTE in trauma patients, risk assessment for VTE and decision for thromboprophylaxis was made by adapting the guideline for the prevention of perioperative VTE in adolescent patients.

RESULTS

Forty-nine patients [25 males and 24 females] with earthquake-related crush syndrome had participated in the study. The median age of the patients was 13.5 (8.8-15.5) years. Seven patients (14.6%) who had no risk factors for thrombosis were considered to be at low risk and did not receive thromboprophylaxis. Thirteen patients (27.1%) with one risk factor for thrombosis were considered to be at moderate risk and 28 patients (58.3%) with two or more risk factors for thrombosis were considered to be at high risk. Moderate-risk patients (n = 8) and high-risk patients aged < 13 years (n = 11) received prophylactic enoxaparin if they could not be mobilized early, while all high-risk patients aged ≥ 13 years (n = 13) received prophylactic enoxaparin.

CONCLUSION

With the decision-making algorithm for thyromboprophylaxis we used, we observed a VTE rate of 2.1% in pediatric patients with earthquake-related crush syndrome.

Derivation and Validation of a Machine Learning Algorithm for Predicting Venous Thromboembolism in Injured Children

BACKGROUND

Venous thromboembolism (VTE) causes significant morbidity in pediatric trauma patients. We applied machine learning algorithms to the Trauma Quality Improvement Program (TQIP) database to develop and validate a risk prediction model for VTE in injured children.

METHODS

Patients ≤18 years were identified from TQIP (2017-2019, n = 383,814). Those administered VTE prophylaxis ≤24 h and missing the outcome (VTE) were removed (n = 347,576). Feature selection identified 15 predictors: intubation, need for supplemental oxygen, spinal injury, pelvic fractures, multiple long bone fractures, major surgery (neurosurgery, thoracic, orthopedic, vascular), age, transfusion requirement, intracranial pressure monitor or external ventricular drain placement, and low Glasgow Coma Scale score. Data was split into training (n = 251,409) and testing (n = 118,175) subsets. Machine learning algorithms were trained, tested, and compared.

RESULTS

Low-risk prediction: For the testing subset, all models outperformed the baseline rate of VTE (0.15%) with a predicted rate of 0.01-0.02% (p < 2.2e^-16). 88.4-89.4% of patients were classified as low risk by the models.

HIGH-RISK PREDICTION

All models outperformed baseline with a predicted rate of VTE ranging from 1.13 to 1.32% (p < 2.2e^-16). The performance of the 3 models was not significantly different.

CONCLUSION

We developed a predictive model that differentiates injured children for development of VTE with high discrimination and can guide prophylaxis use.

LEVEL OF EVIDENCE

Prognostic, Level II.

TYPE OF STUDY

Retrospective, Cross-sectional.

Dabigatran Etexilate: A Review in Pediatric Venous Thromboembolism

Although rare in children, venous thromboembolism (VTE) is markedly more likely in hospitalized patients, particularly with the use of central venous access devices. Dabigatran etexilate (Pradaxa^®) is one of the first direct non-vitamin K antagonist oral anticoagulants (DOAC) approved for use in pediatric patients. It is approved in the EU and USA for the treatment of VTE in patients who have been treated with a parenteral anticoagulant for ≥ 5 days, and for the prevention of recurrent VTE. In an open-label, phase 2b/3 clinical trial in pediatric patients with acute VTE treated for ≈ 3 months, dabigatran etexilate was non-inferior to standard of care (SOC) treatment for the primary composite endpoint of complete thrombus resolution, freedom from recurrent VTE and VTE-related death. In a single-arm phase 3 safety study, few patients experienced recurrent VTE with ≤ 12 months of anticoagulation with dabigatran etexilate. Dabigatran etexilate was generally well tolerated in both studies; bleeding events were mostly minor and, in the phase 2b/3 study, occurred at a similar incidence to SOC. Although further data will be useful, dabigatran etexilate is a valuable and convenient treatment option in pediatric VTE.

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.

The incidence and risk factors for venous thromboembolism in adolescent and young adult oncology patients

BACKGROUND

Venous thromboembolism (VTE) is a known complication among pediatric and adult cancer patients. Adolescent and young adult oncology (AYAO) patients have unique biological and physiological characteristics that make them distinct from other populations. Our objective was to study the VTE incidence, risk factors, and outcomes, which have been understudied in this population.

PROCEDURE

A retrospective case-control study was conducted on AYAO participants with new or relapsed cancer and an imaging confirmed VTE from January 2011 to November 2016 at our institution. Eligible AYAO participants without a history of VTE were designated as controls and were randomly selected from our institution's tumor registry. Demographics, medical history, surgeries, central venous catheter (CVC) data, VTE diagnosis and treatment, relapses, and deaths were abstracted.

RESULTS

Thirty-five VTE cases and 70 controls were included in this analysis. Eighty percent of cases had leukemia or lymphoma (vs. a solid tumor) compared to 58% of controls. The majority of VTEs (57%) were CVC associated, and more than 70% of cases had more than one CVC placed during their cancer treatment versus 34% of controls. Infection was associated with increased VTE risk (OR = 6.35, 95% CI = 2.30, 17.55, p < .0001). VTE cases had increased cancer relapse (23% vs. 10%) and mortality rates (29% vs. 16%) than controls.

CONCLUSION

AYAO participants with a VTE were more likely to have leukemia or lymphoma, more than one CVC or infection. Further studies are needed to identify patients who would benefit from modifiable prevention measures, such as limiting to one CVC, preventing infections, or considering prophylactic anticoagulation for those with a liquid tumor.

Low-molecular-weight heparin versus unfractionated heparin in pediatric traumatic brain injury

OBJECTIVE

The incidence of venous thromboembolism (VTE) in patients with traumatic brain injury (TBI) has increased significantly. The Eastern Association for the Surgery of Trauma recommends using low-molecular-weight heparin (LMWH) over unfractionated heparin (UH) in pediatric patients requiring VTE prophylaxis, although this strategy is unsupported by the literature. In this study, the authors compare the outcomes of pediatric TBI patients receiving LMWH versus UH.

METHODS

The authors performed a 4-year (2014-2017) analysis of the pediatric American College of Surgeons Trauma Quality Improvement Program. All trauma patients (age ≤ 18 years) with TBI requiring thromboprophylaxis with UH or LMWH were potentially eligible for inclusion. Patients who had been transferred, had died in the emergency department, or had penetrating trauma were excluded. Patients were stratified into either the LMWH or the UH group on the basis of the prophylaxis they had received. Patients were matched on the basis of demographics, injury characteristics, vital signs, and transfusion requirements using propensity score matching (PSM). The study endpoints were VTE, death, and craniotomy after initiation of prophylaxis. Univariate analysis was performed after PSM to compare outcomes.

RESULTS

A total of 2479 patients met the inclusion criteria (mean age 15.5 ± 3.7 years and 32.0% female), of which 1570 (63.3%) had received LMWH and 909 (36.7%) had received UH. Before PSM, patients receiving UH were younger, had a lower Glasgow Coma Scale score, and had a higher Injury Severity Score. Patients treated in pediatric hospitals were more likely to receive UH (12.9% vs 9.0%, p < 0.001) than patients treated in adult hospitals. Matched patients receiving UH had a higher incidence of VTE (5.1% vs 2.9%, p = 0.03).

CONCLUSIONS

LMWH prophylaxis in pediatric TBI appears to be more effective than UH in preventing VTE. Large, multicenter prospective studies are warranted to confirm the superiority of LMWH over UH in pediatric patients with TBI. Moreover, outcomes of VTE prophylaxis in the very young remain understudied; therefore, dedicated studies to evaluate this population are needed.

The incidence of venous thromboembolism in children following colorectal resection for inflammatory bowel disease: A multi-center study

BACKGROUND/PURPOSE

Children with inflammatory bowel disease (IBD) have increased risk for venous thromboembolism (VTE). We sought to determine incidence and risk factors for postoperative VTE in a multicenter cohort of pediatric patients undergoing colorectal resection for IBD.

METHODS

Retrospective review of children ≤18 years who underwent colorectal resection for IBD from 2010 to 2016 was performed at four children's hospitals. Primary outcome was VTE that occurred between surgery and last follow-up. Factors associated with VTE were determined using univariable and multivariable analyses.

RESULTS

Two hundred seventy-six patients were included with median age 15 years [13,17]. Forty-two children (15%) received perioperative VTE chemoprophylaxis, and 88 (32%) received mechanical prophylaxis. DVT occurred in 12 patients (4.3%) at a median of 14 days postoperatively [8,147]. Most were portomesenteric (n = 9, 75%) with the remaining catheter-associated DVTs in extremities (n = 3, 25%). There was no association with chemoprophylaxis (p > 0.99). On Cox regression, emergent procedure [HR 18.8, 95%CI: 3.18-111], perioperative plasma transfusion [HR 25.1, 95%CI: 2.4-259], and postoperative infectious complication [HR 10.5, 95%CI: 2.63-41.8] remained predictive of DVT.

CONCLUSION

Less than 5% of pediatric IBD patients developed postoperative VTE. Chemoprophylaxis was not protective but rarely used. Patients with risk factors identified in this study should be monitored or given prophylaxis for VTE.

LEVEL OF EVIDENCE

Treatment Study, Level III.

Occurrence and Risk Factors for Unplanned Catheter Removal in a PICU: Central Venous Catheters Versus Peripherally Inserted Central Venous Catheters

OBJECTIVES

We aimed to identify the occurrence and risk factors for unplanned catheter removal due to catheter-associated complications and the effects on catheter survival probability in a PICU.

DESIGN

Retrospective, single-center, observational study of cases involving conventional central venous catheters or peripherally inserted central venous catheters.

SETTING

The PICU of a tertiary children's hospital.

PATIENTS

Consecutive PICU patients with central venous catheters between April 2016 and February 2019.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

We identified unplanned catheter removals that were related to central line-associated bloodstream infection, thrombosis, and mechanical complications. During the study period, 582 central venous catheters and 474 peripherally inserted central venous catheters were identified. The median durations of catheter placement were 4.0 days for central venous catheters and 13.0 days for peripherally inserted central venous catheters (p < 0.001), and unplanned catheter removals due to catheter-associated complications were in 52 (8.9%) central venous catheter cases and 132 (27.8%) peripherally inserted central venous catheter cases (p < 0.001) (15.0 and 16.0 per 1,000 catheter-days, respectively [p = 0.75]). Unplanned catheter removal was associated with a peripheral catheter tip position among both central venous catheters and peripherally inserted central venous catheters (p < 0.001 and p = 0.001), and it was associated with surgical patient status among peripherally inserted central venous catheters (p = 0.009). In contrast, the use of ultrasound-guided insertion was associated with a lower occurrence of unplanned catheter removal among peripherally inserted central venous catheters (p = 0.01). With regard to catheter survival probability, there was no significant difference between central venous catheters and peripherally inserted central venous catheters (p = 0.23). However, peripherally inserted central venous catheters had a lower occurrence of central line-associated bloodstream infection than central venous catheters (p = 0.03), whereas there was no significant difference in the rates of thrombosis (p = 0.29) and mechanical complications (p = 0.84) between central venous catheters and peripherally inserted central venous catheters.

CONCLUSIONS

In a PICU, peripherally inserted central venous catheters had lower occurrence of central line-associated bloodstream infection than central venous catheters; however, similar catheter survival probabilities were observed between both catheters. A central catheter tip position for both catheters and ultrasound-guided insertion for peripherally inserted central venous catheters may help limit unplanned catheter removal due to catheter-associated complications.

Significant practice variability exists in the prevention of venous thromboembolism in injured children: results from a joint survey of the Pediatric Trauma Society and the Trauma Center Association of America

BACKGROUND/PURPOSE

The purpose of this study was to characterize current practices to prevent venous thromboembolism (VTE) in children and measure adherence to recent joint consensus guidelines from the Pediatric Trauma Society and Eastern Association for the Surgery of Trauma (PTS/EAST).

METHODS

An 18-question survey was sent to the membership of PTS and the Trauma Center Association of American. Responses were compared with Chi-square test.

RESULTS

One hundred twenty-nine members completed the survey. Most respondents were from academic (84.5%), Level 1 pediatric (62.0%) trauma centers. Criteria for VTE prophylaxis varied between hospitals with freestanding pediatric trauma centers significantly more likely to stratify children by risk factors than adult trauma centers (p = 0.020). While awareness of PTS/EAST guidelines (58.7% overall) was not statistically different between hospital types (44% freestanding adult, 52% freestanding pediatric, 71% combined adult pediatric, p = 0.131), self-reported adherence to these guidelines was uniformly low at 37.2% for all respondents. Lastly, in three clinical scenarios, respondents chose VTE screening and prophylaxis plans in accordance with a prospective application of PTS/EAST guidelines 55.0% correctly.

CONCLUSION

Currently no consensus regarding the prevention of VTE in pediatric trauma exists. Prospective application of PTS/EAST guidelines has been limited, likely due to poor quality of evidence and a reliance on post-injury metrics. Results of this survey suggest that further investigation is needed to more clearly define the risk of VTE in children, evaluate, and prospectively validate alternative scoring systems for VTE prevention in injured children.

LEVEL OF EVIDENCE

N/A-Survey.

Prophylaxis for Pediatric Venous Thromboembolism: Current Status and Changes Across Pediatric Orthopaedic Society of North America From 2011

INTRODUCTION

Pediatric venous thromboembolism (VTE) is a concern for orthopaedic surgeons. We sought to query the Pediatric Orthopaedic Society of North America (POSNA) members on current VTE prophylaxis practice and compare those results with those of a previous survey (2011).

METHODS

A 35-question survey was emailed to all active and candidate POSNA members. The survey consisted of questions on personal and practice demographics; knowledge and implementation of various VTE prophylaxis protocols, mechanical and chemical VTE prophylaxis agents, and risk factors; and utilization of scenarios VTE prophylaxis agents for various clinical scenarios. One- and two-way frequency tables were constructed comparing results from the current survey and those of the 2011 survey.

RESULTS

Two hundred thirty-nine surveys were completed (18% respondent rate), with most respondents from an academic/university practice reporting one or two partners (>60%). Half were in practice ≥15 years, and >90% reported an almost exclusive pediatric practice. One-third of the respondents reported familiarity with their institution-defined VTE prophylaxis protocol, and 20% were aware of an institutionally driven age at which all patients receive VTE prophylaxis. The most frequently recognized risk factors to guide VTE prophylaxis were oral contraceptive use, positive family history, and obesity. Respondents indicated a similar frequency of use of a VTE prophylaxis agent (either mechanical or chemical) for spinal fusion, hip reconstruction, and trauma (60% to 65%), with lower frequency for neuromuscular surgery (34%) (P < 0.001). One hundred thirty-seven respondents had a patient sustain a deep vein thrombosis, and 66 had a patient sustain a pulmonary embolism. Compared with responses from 2011, only 20 more respondents reported familiarity with their institution VTE prophylaxis protocol (75 versus 55). In 2018, aspirin was used more frequently than in 2011 (52% versus 19%; P < 0.0001) and enoxaparin was used less frequently (20% versus 41%; P < 0.0001).

DISCUSSION

Over the past 7 years since the first POSNA survey on VTE prophylaxis, most POSNA members are still unaware of their institution specific VTE prophylaxis protocol. Most respondents agree that either mechanical or chemical VTE prophylaxis should be used for spinal fusion, hip reconstruction, and trauma. The use of aspirin as an agent of chemical VTE prophylaxis has increased since 2011.

LEVEL OF EVIDENCE

Level IV. Type of evidence: therapeutic.