Predictors of early versus late timing of pulmonary embolus after traumatic injury

Abstract

OBJECTIVE To identify risk factors predictive of pulmonary embolus (PE) timing after a traumatic injury. METHODS One hundred eight traumatic injury patients with a confirmed diagnosis of PE were classified as early PE (≤4 days, n = 54) or late PE (>4 days, n = 54). Independent predictors of early versus late PE were identified using multivariate logistic regression. RESULTS Half the PEs were diagnosed ≤4 days of injury. Only long bone fractures independently predicted early PE (odds ratio 2.8; 95% confidence interval, 1.1–7.1). Severe head injuries were associated with late PE (odds ratio 11.1; 95% confidence interval, 3.9–31). Established risk factors such as age did not affect timing. CONCLUSIONS Half the PEs were diagnosed ≤4 days after injury. The risk of early PE appeared highest in patients with long bone fractures, and the benefits of immediate prophylaxis may outweigh risks. Patients with severe head injuries appear to have later PE events. Prospective interventional trials in these injury populations are needed.

One-Year Analysis of the Prospective Multicenter SENTRY Clinical Trial: Safety and Effectiveness of the Novate Sentry Bioconvertible Inferior Vena Cava Filter

“…Regarding the design concept and rationale for the Sentry IVC filter to provide protection until bioconversion after 60 days after implantation, contemporary data support the premise that the period of highest risk for PE in patients with temporary contraindications to anticoagulants occurs early. In one study in a group of trauma patients, the average time from injury to PE was determined to be 7.9 days (34), and other studies have found that the majority of trauma-related PE occur < 30 days after the index event (7)(8)(9). In studies of postoperative PE, the mean time from surgery to PE was 3-20 days (10,35,36).…”

Comparing clinical predictors of deep venous thrombosis versus pulmonary embolus after severe injury

“…It is therefore likely that many, if not most, of DVT and PE diagnosed in this cohort were symptomatic, although it has been shown that up to 10% of PE diagnosed in trauma patients are found incidentally. 9 Given these factors, it is probable that overall rates of DVT as well as concurrent DVT/PE are underestimated as many asymptomatic thromboembolic events will have gone undiagnosed. Finally, while a complication rate of 4–8% seems relatively high from a clinical standpoint, statistically these are relatively rare events (i.e.…”

“…An “all possible models” exhaustive search methodology utilizing optimally recoded or transformed variables with subsequent 5-fold cross validation was utilized in order to develop a “best possible model” of independent risk factors for each outcome. 9 Specifically, 19 independent variables were taken from a list of available predictors that were considered clinically relevant from existing literature. All variables containing missing values were completed using a marginal stochastic imputation method that replaces missing data with values found by randomly sampling from the set of all observed sample values for that variable.…”

“…Exhaustive searches were performed to minimize the risk of omitting important models from consideration. 9,22–24 This algorithm estimated all possible logistic regression models that can be constructed, consisting of 2 19 (542,288) models, based on the variables within the dataset using a second order variant of the Akaike Information Criterion (AIC c ), which controls for model complexity and provides a small sample bias adjustment. All models were then ranked using the Generalized Akaike Information Criterion (GAIC) which is robust in the presence of possible model misspecification and controls for model complexity.…”

Early Lower Extremity Fracture Fixation and the Risk of Early Pulmonary Embolus: Filter Before Fixation?

“…Recent studies have attempted to determine those injury types associated with an increased risk of early PEs. 14,15 Currently, a greater understanding of the risks for early PE attributable to patient and injury characteristics and the associated procedures and operative interventions that are performed early after injury is lacking. The main objective of the current analysis was to determine those risk factors that are associated with the development of PE within 72 hours of injury.…”