Trauma Early Mortality Prediction Tool (TEMPT) for assessing 28-day mortality.

Background:Prior mortality prediction models have incorporated severity of anatomic injury quantified by Abbreviated Injury Severity Score (AIS). Using a prospective cohort, a new score independent of AIS was developed using clinical and laboratory markers present on emergency department presentation to predict 28-day mortality. Methods:All patients (n=1427) enrolled in an ongoing prospective cohort study were included. Demographic, laboratory, and clinical data were recorded on admission. True random number generator technique divided the cohort into derivation (n=707) and validation groups (n=720). Using Youden indices, threshold values were selected for each potential predictor in the derivation cohort. Logistic regression was used to identify independent predictors. Significant variables were equally weighted to create a new mortality prediction score, the Trauma Early Mortality Prediction Tool (TEMPT) score. Area under the curve (AUC) was tested in the validation group. Pairwise comparison of Trauma Injury Severity Score (TRISS), Revised Trauma Score, Glasgow Coma Scale, and Injury Severity Score were tested against the TEMPT score. Results:There was no difference between baseline characteristics between derivation and validation groups. In multiple logistic regression, a model with presence of traumatic brain injury, increased age, elevated systolic blood pressure, decreased base excess, prolonged partial thromboplastin time, increased international normalized ratio (INR), and decreased temperature accurately predicted mortality at 28 days (AUC 0.93, 95% CI 0.90 to 0.96, P<0.001). In the validation cohort, this score, termed TEMPT, predicted 28-day mortality with an AUC 0.94 (95% CI 0.92 to 0.97). The TEMPT score preformed similarly to the revised TRISS score for severely injured patients and was highly predictive in those having mild to moderate injury. Discussion:TEMPT is a simple AIS-independent mortality prediction tool applicable very early following injury. TEMPT provides an AIS-independent score that could be used for early identification of those at risk of doing poorly following even minor injury. Level of evidence:Level II

Obesity and clotting

BackgroundAlthough obese patients have high thrombosis rates following injury, the role of obesity in coagulation after trauma remains unknown. We hypothesized that body mass index (BMI) is independently associated with increased measures of hypercoagulability longitudinally after injury.MethodsData were prospectively collected for 377 consecutive highest-level trauma activation patients with a BMI of 18.5 kg/m² or greater. Standard coagulation measures, citrated kaolin and functional fibrinogen thromboelastography, as well as clotting factors were measured at 0 hour to 120 hours. BMI categories were defined as normal weight (18.5-24.99 kg/m²), overweight (25-29.99 kg/m²), and obese (≥30 kg/m²).ResultsThe 377 patients were mostly male (81%) and had blunt injury (61%), with a median BMI of 25.8 kg/m². Of the patients, 42% were normal weight (median BMI, 22.5 kg/m²). There were no differences in age, sex, Injury Severity Score (ISS), or base deficit between groups. There were no differences in admission international normalized ratio/partial thromboplastin time or factors II, V, VII, VIII, and X; antithrombin III; or protein C. However, obese patients had higher admission platelet counts (303 × 10⁹/L vs. 269 × 10⁹/L, p = 0.004), lower D-dimer (1.88 μg/mL vs. 4.00 μg/mL, p = 0.004), and a trend toward higher factor IX (134% vs. 119% activity, p = 0.042) compared with normal weight patients. Measured by thromboelastography, clot strength (maximum amplitude) and functional fibrinogen level (FLEV) were also higher on admission for obese patients (maximum amplitude, 65.7 mm vs. 63.4 mm, p = 0.016; FLEV, 407 mg/dL vs. 351 mg/dL, p = 0.008). In multiple linear regression, the relationship of BMI to clot strength, FLEV, and factor IX persisted through 24 hours. Similarly, the relationship of BMI and platelet count persisted through 120 hours (all p < 0.05). In multiple logistic regression, for every 5-kg/m² increase in BMI, there was an 85% increase in odds of thromboembolic complication (odds ratio, 1.85; 95% confidence interval, 1.13-3.08; p = 0.017).ConclusionObese trauma patients are hypercoagulable compared with their similarly injured normal-weight counterparts, which persists longitudinally after injury. The significance of this hypercoagulability requires elucidation for guidance of anticoagulation in this at-risk group.Level of evidencePrognostic study, level III

Heterochromatic breaks move to the nuclear periphery to continue recombinational repair.

Heterochromatin mostly comprises repeated sequences prone to harmful ectopic recombination during double-strand break (DSB) repair. In Drosophila cells, 'safe' homologous recombination (HR) repair of heterochromatic breaks relies on a specialized pathway that relocalizes damaged sequences away from the heterochromatin domain before strand invasion. Here we show that heterochromatic DSBs move to the nuclear periphery to continue HR repair. Relocalization depends on nuclear pores and inner nuclear membrane proteins (INMPs) that anchor repair sites to the nuclear periphery through the Smc5/6-interacting proteins STUbL/RENi. Both the initial block to HR progression inside the heterochromatin domain, and the targeting of repair sites to the nuclear periphery, rely on SUMO and SUMO E3 ligases. This study reveals a critical role for SUMOylation in the spatial and temporal regulation of HR repair in heterochromatin, and identifies the nuclear periphery as a specialized site for heterochromatin repair in a multicellular eukaryote

Individual clotting factor contributions to mortality following trauma

BackgroundAcute traumatic coagulopathy affects 20% to 30% of trauma patients, but the extensive collinearity of the coagulation cascade complicates attempts to clarify global clotting factor dysfunction. This study aimed to characterize phenotypes of clotting factor dysfunction and their contributions to mortality after major trauma.MethodsThis prospective cohort study examines all adult trauma patients of the highest activation level presenting to San Francisco General Hospital between February 2005 and February 2015. Factors II, V, VII, VIII, IX, and X and protein C activity on admission and mortality status at 28 days were assessed. Predictors of 28-day mortality in univariate analysis were included in multiple logistic regression controlling for traumatic brain injury (TBI), acidosis, age, and mechanism of injury. Principal component analysis was utilized to identify phenotypic coagulation.ResultsComplete coagulation factor data were available for 876 (61%) of 1,429 patients. In multiple logistic regression, factors V (odds ratio [OR], 0.86; 95% confidence interval [CI], 0.76-0.97), VIII (OR, 0.97; 95% CI, 0.95-0.99), and X (OR, 0.79; 95% CI, 0.68-0.92) and protein C (OR, 1.17; 95% CI, 1.05-1.30) significantly predicted 28-day mortality after controlling for age, base deficit, mechanism of injury, and TBI. Principal component analysis identified two significant principal components (Phenotypes 1 and 2) that accounted for 66.3% of the total variance. Phenotype 1 (factors II, VII, IX, and X and protein C abnormalities) explained 49.3% and was associated with increased injury, coagulopathy, TBI, and mortality. Phenotype 2 (factors V and VIII abnormalities) explained 17.0% and was associated with increased coagulopathy, blunt injury, and mortality. Only Phenotype 2 remained significantly associated with 28-day mortality in multiple logistic regression.ConclusionsPrincipal component analysis identified two distinct phenotypes within the entirety of global clotting factor abnormalities, and these findings substantiate the crucial association of factors V and VIII on mortality following trauma. This may be the first step toward identifying unique phenotypes after injury and personalizing hemostatic resuscitation.Level of evidencePrognostic study, level III

Characterization of distinct coagulopathic phenotypes in injury: Pathway-specific drivers and implications for individualized treatment.

BackgroundInternational normalized ratio (INR) and partial thromboplastin time (PTT) are used interchangeably to diagnose acute traumatic coagulopathy but reflect disparate activation pathways. In this study, we identified injury/patient characteristics and coagulation factors that drive contact pathway, tissue factor pathway (TF), and common pathway dysfunction by examining injured patients with discordant coagulopathies. We hypothesized that patients with INR/PTT discordance reflect differing phenotypes representing contact versus tissue factor pathway perturbations and that characterization will provide targets to guide individualized resuscitation.MethodsPlasma samples were prospectively collected from 1,262 critically injured patients at a single Level I trauma center. Standard coagulation measures and an extensive panel of procoagulant and anticoagulant factors were assayed and analyzed with demographic and outcome data.ResultsFourteen percent of patients were coagulopathic on admission. Among these, 48% had abnormal INR and PTT (BOTH), 43% had isolated prolonged PTT (PTT-CONTACT), and 9% had isolated elevated INR (INR-TF). PTT-CONTACT and BOTH had lower Glasgow Coma Scale score than INR-TF (p < 0.001). INR-TF had decreased factor VII activity compared with PTT-CONTACT, whereas PTT-CONTACT had decreased factor VIII activity compared with INR-TF. All coagulopathic patients had factor V deficits, but activity was lowest in BOTH, suggesting an additive downstream effect of disordered activation pathways. Patients with PTT-CONTACT received half as much packed red blood cell and fresh frozen plasma as did the other groups (p < 0.001). Despite resuscitation, mortality was higher for coagulopathic patients; mortality was highest in BOTH and higher in PTT-CONTACT than in INR-TF (71%, 60%, 41%; p = 0.04).ConclusionsDiscordant phenotypes demonstrate differential factor deficiencies consistent with dysfunction of contact versus tissue factor pathways with additive effects from common pathway dysfunction. Recognition and treatment of pathway-specific factor deficiencies driving different coagulopathic phenotypes in injured patients may individualize resuscitation and improve outcomes.Level of evidencePrognostic/epidemiological study, level II

Improving staging of rectal cancer in the pelvis: the role of PET/MRI

Purpose: The role of positron emission tomography/magnetic resonance (PET/MR) in evaluating the local extent of rectal cancer remains uncertain. This study aimed to investigate the possible role of PET/MR versus magnetic resonance (MR) in clinically staging rectal cancer. Methods: This retrospective two-center cohort study of 62 patients with untreated rectal cancer investigated the possible role of baseline staging PET/MR versus stand-alone MR in determination of clinical stage. Two readers reviewed T and N stage, mesorectal fascia involvement, tumor length, distance from the anal verge, sphincter involvement, and extramural vascular invasion (EMVI). Sigmoidoscopy, digital rectal examination, and follow-up imaging, along with surgery when available, served as the reference standard. Results: PET/MR outperformed MR in evaluating tumor size (42.5 ± 21.03 mm per the reference standard, 54 ± 20.45 mm by stand-alone MR, and 44 ± 20 mm by PET/MR, P = 0.004), and in identifying N status (correct by MR in 36/62 patients [58%] and by PET/MR in 49/62 cases [79%]; P = 0.02) and external sphincter infiltration (correct by MR in 6/10 and by PET/MR in 9/10; P = 0.003). No statistically significant differences were observed in relation to any other features. Conclusion: PET/MR provides a more precise assessment of the local extent of rectal cancers in evaluating cancer length, N status, and external sphincter involvement. PET/MR offers the opportunity to improve clinical decision-making, especially when evaluating low rectal tumors with possible external sphincter involvement